318 changed files with 26106 additions and 2056 deletions
--- a/.gitmodules
+++ b/.gitmodules
@ -0,0 +1,4 @@
+[submodule "Vendor/libmobilecoin-ios-artifacts"]
+	path = Vendor/libmobilecoin-ios-artifacts
+	url = https://github.com/mobilecoinofficial/libmobilecoin-ios-artifacts.git
+	shallow = true
--- a/Example/Example.xcodeproj/project.pbxproj
+++ b/Example/Example.xcodeproj/project.pbxproj
@ -0,0 +1,514 @@
+// !$*UTF8*$!
+{
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+	objects = {
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+/* End PBXFrameworksBuildPhase section */
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+				2706868B2474C4D800B82C57 /* Example */,
+				27A39C3B24C2622600B44786 /* TestPlans */,
+				2706868A2474C4D800B82C57 /* Products */,
+				4256C0AB87AF2BC2F24F1B92 /* Pods */,
+				9E89A7B3975ECA671C9D8346 /* Frameworks */,
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+			children = (
+				270686892474C4D800B82C57 /* Example.app */,
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+			name = Products;
+			sourceTree = "<group>";
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+		2706868B2474C4D800B82C57 /* Example */ = {
+			isa = PBXGroup;
+			children = (
+				2706868C2474C4D800B82C57 /* AppDelegate.swift */,
+				270686922474C4DA00B82C57 /* Assets.xcassets */,
+				270686972474C4DA00B82C57 /* LaunchScreen.storyboard */,
+				2706869A2474C4DA00B82C57 /* Info.plist */,
+				270686942474C4DA00B82C57 /* Preview Content */,
+			);
+			path = Example;
+			sourceTree = "<group>";
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+				270686952474C4DA00B82C57 /* Preview Assets.xcassets */,
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+				27A1FABE24E8B89C001A0614 /* Performance Tests.xctestplan */,
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+			isa = PBXGroup;
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+				FC106CAA4E993C2D6301C5CA /* Pods-Example.testable release.xcconfig */,
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+			sourceTree = "<group>";
+		};
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+			children = (
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+			sourceTree = "<group>";
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+			buildPhases = (
+				A960891E414B6399548D3852 /* [CP] Check Pods Manifest.lock */,
+				270686852474C4D800B82C57 /* Sources */,
+				270686862474C4D800B82C57 /* Frameworks */,
+				270686872474C4D800B82C57 /* Resources */,
+				1851CDD4271ED50E0D6D8B7B /* [CP] Embed Pods Frameworks */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+			);
+			name = Example;
+			productName = Example;
+			productReference = 270686892474C4D800B82C57 /* Example.app */;
+			productType = "com.apple.product-type.application";
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+/* End PBXNativeTarget section */
+
+/* Begin PBXProject section */
+		270686812474C4D800B82C57 /* Project object */ = {
+			isa = PBXProject;
+			attributes = {
+				LastSwiftUpdateCheck = 1140;
+				LastUpgradeCheck = 1250;
+				ORGANIZATIONNAME = "MobileCoin Inc.";
+				TargetAttributes = {
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+			buildConfigurationList = 270686842474C4D800B82C57 /* Build configuration list for PBXProject "Example" */;
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+			knownRegions = (
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+				270686882474C4D800B82C57 /* Example */,
+			);
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+				270686992474C4DA00B82C57 /* LaunchScreen.storyboard in Resources */,
+				27A1FABF24E8B89C001A0614 /* Performance Tests.xctestplan in Resources */,
+				270686962474C4DA00B82C57 /* Preview Assets.xcassets in Resources */,
+				270686932474C4DA00B82C57 /* Assets.xcassets in Resources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+/* End PBXResourcesBuildPhase section */
+
+/* Begin PBXShellScriptBuildPhase section */
+		1851CDD4271ED50E0D6D8B7B /* [CP] Embed Pods Frameworks */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputFileListPaths = (
+				"${PODS_ROOT}/Target Support Files/Pods-Example/Pods-Example-frameworks-${CONFIGURATION}-input-files.xcfilelist",
+			);
+			name = "[CP] Embed Pods Frameworks";
+			outputFileListPaths = (
+				"${PODS_ROOT}/Target Support Files/Pods-Example/Pods-Example-frameworks-${CONFIGURATION}-output-files.xcfilelist",
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "\"${PODS_ROOT}/Target Support Files/Pods-Example/Pods-Example-frameworks.sh\"\n";
+			showEnvVarsInLog = 0;
+		};
+		A960891E414B6399548D3852 /* [CP] Check Pods Manifest.lock */ = {
+			isa = PBXShellScriptBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			inputFileListPaths = (
+			);
+			inputPaths = (
+				"${PODS_PODFILE_DIR_PATH}/Podfile.lock",
+				"${PODS_ROOT}/Manifest.lock",
+			);
+			name = "[CP] Check Pods Manifest.lock";
+			outputFileListPaths = (
+			);
+			outputPaths = (
+				"$(DERIVED_FILE_DIR)/Pods-Example-checkManifestLockResult.txt",
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+			shellPath = /bin/sh;
+			shellScript = "diff \"${PODS_PODFILE_DIR_PATH}/Podfile.lock\" \"${PODS_ROOT}/Manifest.lock\" > /dev/null\nif [ $? != 0 ] ; then\n    # print error to STDERR\n    echo \"error: The sandbox is not in sync with the Podfile.lock. Run 'pod install' or update your CocoaPods installation.\" >&2\n    exit 1\nfi\n# This output is used by Xcode 'outputs' to avoid re-running this script phase.\necho \"SUCCESS\" > \"${SCRIPT_OUTPUT_FILE_0}\"\n";
+			showEnvVarsInLog = 0;
+		};
+/* End PBXShellScriptBuildPhase section */
+
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+				2706868D2474C4D800B82C57 /* AppDelegate.swift in Sources */,
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+			);
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+/* End PBXVariantGroup section */
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+				CLANG_ANALYZER_NONNULL = YES;
+				CLANG_ANALYZER_NUMBER_OBJECT_CONVERSION = YES_AGGRESSIVE;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++14";
+				CLANG_CXX_LIBRARY = "libc++";
+				CLANG_ENABLE_MODULES = YES;
+				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_ENABLE_OBJC_WEAK = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
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+				CLANG_WARN_COMMA = YES;
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+				CLANG_WARN_DEPRECATED_OBJC_IMPLEMENTATIONS = YES;
+				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
+				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
+				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
+				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_IMPLICIT_RETAIN_SELF = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
+				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_QUOTED_INCLUDE_IN_FRAMEWORK_HEADER = YES;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
+				CLANG_WARN_UNGUARDED_AVAILABILITY = YES_AGGRESSIVE;
+				CLANG_WARN_UNREACHABLE_CODE = YES;
+				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
+				COPY_PHASE_STRIP = NO;
+				DEBUG_INFORMATION_FORMAT = dwarf;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				ENABLE_TESTABILITY = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu11;
+				GCC_DYNAMIC_NO_PIC = NO;
+				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_OPTIMIZATION_LEVEL = 0;
+				GCC_PREPROCESSOR_DEFINITIONS = (
+					"DEBUG=1",
+					"$(inherited)",
+				);
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
+				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
+				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
+				GCC_WARN_UNUSED_FUNCTION = YES;
+				GCC_WARN_UNUSED_VARIABLE = YES;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.4;
+				MTL_ENABLE_DEBUG_INFO = INCLUDE_SOURCE;
+				MTL_FAST_MATH = YES;
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+				SDKROOT = iphoneos;
+				SWIFT_ACTIVE_COMPILATION_CONDITIONS = DEBUG;
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+		};
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+				ALWAYS_SEARCH_USER_PATHS = NO;
+				CLANG_ANALYZER_NONNULL = YES;
+				CLANG_ANALYZER_NUMBER_OBJECT_CONVERSION = YES_AGGRESSIVE;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++14";
+				CLANG_CXX_LIBRARY = "libc++";
+				CLANG_ENABLE_MODULES = YES;
+				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_ENABLE_OBJC_WEAK = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
+				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
+				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_DEPRECATED_OBJC_IMPLEMENTATIONS = YES;
+				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
+				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
+				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
+				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_IMPLICIT_RETAIN_SELF = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
+				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_QUOTED_INCLUDE_IN_FRAMEWORK_HEADER = YES;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
+				CLANG_WARN_UNGUARDED_AVAILABILITY = YES_AGGRESSIVE;
+				CLANG_WARN_UNREACHABLE_CODE = YES;
+				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
+				COPY_PHASE_STRIP = NO;
+				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
+				ENABLE_NS_ASSERTIONS = NO;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu11;
+				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
+				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
+				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
+				GCC_WARN_UNUSED_FUNCTION = YES;
+				GCC_WARN_UNUSED_VARIABLE = YES;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.4;
+				MTL_ENABLE_DEBUG_INFO = NO;
+				MTL_FAST_MATH = YES;
+				SDKROOT = iphoneos;
+				SWIFT_COMPILATION_MODE = wholemodule;
+				SWIFT_OPTIMIZATION_LEVEL = "-O";
+				VALIDATE_PRODUCT = YES;
+			};
+			name = Release;
+		};
+		2706869E2474C4DA00B82C57 /* Debug */ = {
+			isa = XCBuildConfiguration;
+			baseConfigurationReference = 05E35D1FAC2827984EE8B421 /* Pods-Example.debug.xcconfig */;
+			buildSettings = {
+				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
+				CODE_SIGN_STYLE = Automatic;
+				DEVELOPMENT_ASSET_PATHS = "\"Example/Preview Content\"";
+				DEVELOPMENT_TEAM = 8JT9JJD9Y5;
+				ENABLE_ONLY_ACTIVE_RESOURCES = NO;
+				ENABLE_PREVIEWS = YES;
+				INFOPLIST_FILE = Example/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+				);
+				ONLY_ACTIVE_ARCH = NO;
+				PRODUCT_BUNDLE_IDENTIFIER = com.mobilecoin.Example;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+			};
+			name = Debug;
+		};
+		2706869F2474C4DA00B82C57 /* Release */ = {
+			isa = XCBuildConfiguration;
+			baseConfigurationReference = 3AF40DB60A0ADA2CB879AE38 /* Pods-Example.release.xcconfig */;
+			buildSettings = {
+				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
+				CODE_SIGN_STYLE = Automatic;
+				DEVELOPMENT_ASSET_PATHS = "\"Example/Preview Content\"";
+				DEVELOPMENT_TEAM = 8JT9JJD9Y5;
+				ENABLE_ONLY_ACTIVE_RESOURCES = NO;
+				ENABLE_PREVIEWS = YES;
+				INFOPLIST_FILE = Example/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+				);
+				PRODUCT_BUNDLE_IDENTIFIER = com.mobilecoin.Example;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+			};
+			name = Release;
+		};
+		274D3FAD24E8B5DD004E2F4A /* Testable Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				CLANG_ANALYZER_NONNULL = YES;
+				CLANG_ANALYZER_NUMBER_OBJECT_CONVERSION = YES_AGGRESSIVE;
+				CLANG_CXX_LANGUAGE_STANDARD = "gnu++14";
+				CLANG_CXX_LIBRARY = "libc++";
+				CLANG_ENABLE_MODULES = YES;
+				CLANG_ENABLE_OBJC_ARC = YES;
+				CLANG_ENABLE_OBJC_WEAK = YES;
+				CLANG_WARN_BLOCK_CAPTURE_AUTORELEASING = YES;
+				CLANG_WARN_BOOL_CONVERSION = YES;
+				CLANG_WARN_COMMA = YES;
+				CLANG_WARN_CONSTANT_CONVERSION = YES;
+				CLANG_WARN_DEPRECATED_OBJC_IMPLEMENTATIONS = YES;
+				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;
+				CLANG_WARN_DOCUMENTATION_COMMENTS = YES;
+				CLANG_WARN_EMPTY_BODY = YES;
+				CLANG_WARN_ENUM_CONVERSION = YES;
+				CLANG_WARN_INFINITE_RECURSION = YES;
+				CLANG_WARN_INT_CONVERSION = YES;
+				CLANG_WARN_NON_LITERAL_NULL_CONVERSION = YES;
+				CLANG_WARN_OBJC_IMPLICIT_RETAIN_SELF = YES;
+				CLANG_WARN_OBJC_LITERAL_CONVERSION = YES;
+				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
+				CLANG_WARN_QUOTED_INCLUDE_IN_FRAMEWORK_HEADER = YES;
+				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
+				CLANG_WARN_STRICT_PROTOTYPES = YES;
+				CLANG_WARN_SUSPICIOUS_MOVE = YES;
+				CLANG_WARN_UNGUARDED_AVAILABILITY = YES_AGGRESSIVE;
+				CLANG_WARN_UNREACHABLE_CODE = YES;
+				CLANG_WARN__DUPLICATE_METHOD_MATCH = YES;
+				COPY_PHASE_STRIP = NO;
+				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
+				ENABLE_NS_ASSERTIONS = NO;
+				ENABLE_STRICT_OBJC_MSGSEND = YES;
+				GCC_C_LANGUAGE_STANDARD = gnu11;
+				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
+				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
+				GCC_WARN_UNDECLARED_SELECTOR = YES;
+				GCC_WARN_UNINITIALIZED_AUTOS = YES_AGGRESSIVE;
+				GCC_WARN_UNUSED_FUNCTION = YES;
+				GCC_WARN_UNUSED_VARIABLE = YES;
+				IPHONEOS_DEPLOYMENT_TARGET = 13.4;
+				MTL_ENABLE_DEBUG_INFO = NO;
+				MTL_FAST_MATH = YES;
+				SDKROOT = iphoneos;
+				SWIFT_COMPILATION_MODE = wholemodule;
+				SWIFT_OPTIMIZATION_LEVEL = "-O";
+				VALIDATE_PRODUCT = YES;
+			};
+			name = "Testable Release";
+		};
+		274D3FAE24E8B5DD004E2F4A /* Testable Release */ = {
+			isa = XCBuildConfiguration;
+			baseConfigurationReference = FC106CAA4E993C2D6301C5CA /* Pods-Example.testable release.xcconfig */;
+			buildSettings = {
+				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
+				CODE_SIGN_STYLE = Automatic;
+				DEVELOPMENT_ASSET_PATHS = "\"Example/Preview Content\"";
+				DEVELOPMENT_TEAM = 8JT9JJD9Y5;
+				ENABLE_ONLY_ACTIVE_RESOURCES = NO;
+				ENABLE_PREVIEWS = YES;
+				INFOPLIST_FILE = Example/Info.plist;
+				IPHONEOS_DEPLOYMENT_TARGET = 10.0;
+				LD_RUNPATH_SEARCH_PATHS = (
+					"$(inherited)",
+					"@executable_path/Frameworks",
+				);
+				PRODUCT_BUNDLE_IDENTIFIER = com.mobilecoin.Example;
+				PRODUCT_NAME = "$(TARGET_NAME)";
+				SWIFT_VERSION = 5.0;
+				TARGETED_DEVICE_FAMILY = "1,2";
+			};
+			name = "Testable Release";
+		};
+/* End XCBuildConfiguration section */
+
+/* Begin XCConfigurationList section */
+		270686842474C4D800B82C57 /* Build configuration list for PBXProject "Example" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				2706869B2474C4DA00B82C57 /* Debug */,
+				2706869C2474C4DA00B82C57 /* Release */,
+				274D3FAD24E8B5DD004E2F4A /* Testable Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
+		2706869D2474C4DA00B82C57 /* Build configuration list for PBXNativeTarget "Example" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				2706869E2474C4DA00B82C57 /* Debug */,
+				2706869F2474C4DA00B82C57 /* Release */,
+				274D3FAE24E8B5DD004E2F4A /* Testable Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
+/* End XCConfigurationList section */
+	};
+	rootObject = 270686812474C4D800B82C57 /* Project object */;
+}
--- a/Example/Example.xcworkspace/contents.xcworkspacedata
+++ b/Example/Example.xcworkspace/contents.xcworkspacedata
@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Workspace
+   version = "1.0">
+   <FileRef
+      location = "group:Example.xcodeproj">
+   </FileRef>
+   <FileRef
+      location = "group:Pods/Pods.xcodeproj">
+   </FileRef>
+</Workspace>
--- a/Example/Example.xcworkspace/xcshareddata/IDETemplateMacros.plist
+++ b/Example/Example.xcworkspace/xcshareddata/IDETemplateMacros.plist
@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+<key>FILEHEADER</key>
+<string>
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//</string>
+</dict>
+</plist>
--- a/Example/Example.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist
+++ b/Example/Example.xcworkspace/xcshareddata/IDEWorkspaceChecks.plist
@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>IDEDidComputeMac32BitWarning</key>
+	<true/>
+</dict>
+</plist>
--- a/Example/Example.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings
+++ b/Example/Example.xcworkspace/xcshareddata/WorkspaceSettings.xcsettings
@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>PreviewsEnabled</key>
+	<false/>
+</dict>
+</plist>
--- a/Example/Example.xcworkspace/xcshareddata/xcschemes/Integration
+++ b/Example/Example.xcworkspace/xcshareddata/xcschemes/Integration
@ -0,0 +1,71 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1250"
+   version = "1.7">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "45F542481CBFF9E786B4F9148AC9D6F2"
+               BuildableName = "MobileCoin-Unit-Core-IntegrationTests.xctest"
+               BlueprintName = "MobileCoin-Unit-Core-IntegrationTests"
+               ReferencedContainer = "container:Pods/Pods.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <TestPlans>
+         <TestPlanReference
+            reference = "container:TestPlans/Integration Tests.xctestplan"
+            default = "YES">
+         </TestPlanReference>
+      </TestPlans>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "45F542481CBFF9E786B4F9148AC9D6F2"
+            BuildableName = "MobileCoin-Unit-Core-IntegrationTests.xctest"
+            BlueprintName = "MobileCoin-Unit-Core-IntegrationTests"
+            ReferencedContainer = "container:Pods/Pods.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Testable Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>
--- a/Example/Example.xcworkspace/xcshareddata/xcschemes/Performance
+++ b/Example/Example.xcworkspace/xcshareddata/xcschemes/Performance
@ -0,0 +1,71 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1250"
+   version = "1.7">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "E8A0545E992AC3A0A6B313DAF029D326"
+               BuildableName = "MobileCoin-UI-Core-PerformanceTests.xctest"
+               BlueprintName = "MobileCoin-UI-Core-PerformanceTests"
+               ReferencedContainer = "container:Pods/Pods.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Testable Release"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <TestPlans>
+         <TestPlanReference
+            reference = "container:TestPlans/Performance Tests.xctestplan"
+            default = "YES">
+         </TestPlanReference>
+      </TestPlans>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "E8A0545E992AC3A0A6B313DAF029D326"
+            BuildableName = "MobileCoin-UI-Core-PerformanceTests.xctest"
+            BlueprintName = "MobileCoin-UI-Core-PerformanceTests"
+            ReferencedContainer = "container:Pods/Pods.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Testable Release">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Testable Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>
--- a/Example/Example.xcworkspace/xcshareddata/xcschemes/Unit
+++ b/Example/Example.xcworkspace/xcshareddata/xcschemes/Unit
@ -0,0 +1,71 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Scheme
+   LastUpgradeVersion = "1250"
+   version = "1.7">
+   <BuildAction
+      parallelizeBuildables = "YES"
+      buildImplicitDependencies = "YES">
+      <BuildActionEntries>
+         <BuildActionEntry
+            buildForTesting = "YES"
+            buildForRunning = "YES"
+            buildForProfiling = "YES"
+            buildForArchiving = "YES"
+            buildForAnalyzing = "YES">
+            <BuildableReference
+               BuildableIdentifier = "primary"
+               BlueprintIdentifier = "C10663274EBBCA6839AB2898903FF5CB"
+               BuildableName = "MobileCoin-Unit-Core-Tests.xctest"
+               BlueprintName = "MobileCoin-Unit-Core-Tests"
+               ReferencedContainer = "container:Pods/Pods.xcodeproj">
+            </BuildableReference>
+         </BuildActionEntry>
+      </BuildActionEntries>
+   </BuildAction>
+   <TestAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      shouldUseLaunchSchemeArgsEnv = "YES">
+      <TestPlans>
+         <TestPlanReference
+            reference = "container:TestPlans/Unit Tests.xctestplan"
+            default = "YES">
+         </TestPlanReference>
+      </TestPlans>
+   </TestAction>
+   <LaunchAction
+      buildConfiguration = "Debug"
+      selectedDebuggerIdentifier = "Xcode.DebuggerFoundation.Debugger.LLDB"
+      selectedLauncherIdentifier = "Xcode.DebuggerFoundation.Launcher.LLDB"
+      launchStyle = "0"
+      useCustomWorkingDirectory = "NO"
+      ignoresPersistentStateOnLaunch = "NO"
+      debugDocumentVersioning = "YES"
+      debugServiceExtension = "internal"
+      allowLocationSimulation = "YES">
+   </LaunchAction>
+   <ProfileAction
+      buildConfiguration = "Release"
+      shouldUseLaunchSchemeArgsEnv = "YES"
+      savedToolIdentifier = ""
+      useCustomWorkingDirectory = "NO"
+      debugDocumentVersioning = "YES">
+      <MacroExpansion>
+         <BuildableReference
+            BuildableIdentifier = "primary"
+            BlueprintIdentifier = "C10663274EBBCA6839AB2898903FF5CB"
+            BuildableName = "MobileCoin-Unit-Core-Tests.xctest"
+            BlueprintName = "MobileCoin-Unit-Core-Tests"
+            ReferencedContainer = "container:Pods/Pods.xcodeproj">
+         </BuildableReference>
+      </MacroExpansion>
+   </ProfileAction>
+   <AnalyzeAction
+      buildConfiguration = "Debug">
+   </AnalyzeAction>
+   <ArchiveAction
+      buildConfiguration = "Testable Release"
+      revealArchiveInOrganizer = "YES">
+   </ArchiveAction>
+</Scheme>
--- a/Example/Example/AppDelegate.swift
+++ b/Example/Example/AppDelegate.swift
@ -0,0 +1,16 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import UIKit
+
+@UIApplicationMain
+class AppDelegate: UIResponder, UIApplicationDelegate {
+
+    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
+        // Override point for customization after application launch.
+        return true
+    }
+
+}
+
--- a/Example/Example/Assets.xcassets/AppIcon.appiconset/Contents.json
+++ b/Example/Example/Assets.xcassets/AppIcon.appiconset/Contents.json
@ -0,0 +1,98 @@
+{
+  "images" : [
+    {
+      "idiom" : "iphone",
+      "scale" : "2x",
+      "size" : "20x20"
+    },
+    {
+      "idiom" : "iphone",
+      "scale" : "3x",
+      "size" : "20x20"
+    },
+    {
+      "idiom" : "iphone",
+      "scale" : "2x",
+      "size" : "29x29"
+    },
+    {
+      "idiom" : "iphone",
+      "scale" : "3x",
+      "size" : "29x29"
+    },
+    {
+      "idiom" : "iphone",
+      "scale" : "2x",
+      "size" : "40x40"
+    },
+    {
+      "idiom" : "iphone",
+      "scale" : "3x",
+      "size" : "40x40"
+    },
+    {
+      "idiom" : "iphone",
+      "scale" : "2x",
+      "size" : "60x60"
+    },
+    {
+      "idiom" : "iphone",
+      "scale" : "3x",
+      "size" : "60x60"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "1x",
+      "size" : "20x20"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "2x",
+      "size" : "20x20"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "1x",
+      "size" : "29x29"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "2x",
+      "size" : "29x29"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "1x",
+      "size" : "40x40"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "2x",
+      "size" : "40x40"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "1x",
+      "size" : "76x76"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "2x",
+      "size" : "76x76"
+    },
+    {
+      "idiom" : "ipad",
+      "scale" : "2x",
+      "size" : "83.5x83.5"
+    },
+    {
+      "idiom" : "ios-marketing",
+      "scale" : "1x",
+      "size" : "1024x1024"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}
--- a/Example/Example/Assets.xcassets/Contents.json
+++ b/Example/Example/Assets.xcassets/Contents.json
@ -0,0 +1,6 @@
+{
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}
--- a/Example/Example/Base.lproj/LaunchScreen.storyboard
+++ b/Example/Example/Base.lproj/LaunchScreen.storyboard
@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="17701" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" launchScreen="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="01J-lp-oVM">
+    <device id="retina6_1" orientation="portrait" appearance="light"/>
+    <dependencies>
+        <deployment identifier="iOS"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="17703"/>
+        <capability name="Safe area layout guides" minToolsVersion="9.0"/>
+        <capability name="System colors in document resources" minToolsVersion="11.0"/>
+        <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>
+    </dependencies>
+    <scenes>
+        <!--View Controller-->
+        <scene sceneID="EHf-IW-A2E">
+            <objects>
+                <viewController id="01J-lp-oVM" sceneMemberID="viewController">
+                    <view key="view" contentMode="scaleToFill" id="Ze5-6b-2t3">
+                        <rect key="frame" x="0.0" y="0.0" width="414" height="896"/>
+                        <autoresizingMask key="autoresizingMask" widthSizable="YES" heightSizable="YES"/>
+                        <viewLayoutGuide key="safeArea" id="6Tk-OE-BBY"/>
+                        <color key="backgroundColor" systemColor="systemBackgroundColor"/>
+                    </view>
+                </viewController>
+                <placeholder placeholderIdentifier="IBFirstResponder" id="iYj-Kq-Ea1" userLabel="First Responder" sceneMemberID="firstResponder"/>
+            </objects>
+            <point key="canvasLocation" x="53" y="375"/>
+        </scene>
+    </scenes>
+    <resources>
+        <systemColor name="systemBackgroundColor">
+            <color white="1" alpha="1" colorSpace="custom" customColorSpace="genericGamma22GrayColorSpace"/>
+        </systemColor>
+    </resources>
+</document>
--- a/Example/Example/Info.plist
+++ b/Example/Example/Info.plist
@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+	<key>CFBundleDevelopmentRegion</key>
+	<string>$(DEVELOPMENT_LANGUAGE)</string>
+	<key>CFBundleExecutable</key>
+	<string>$(EXECUTABLE_NAME)</string>
+	<key>CFBundleIdentifier</key>
+	<string>$(PRODUCT_BUNDLE_IDENTIFIER)</string>
+	<key>CFBundleInfoDictionaryVersion</key>
+	<string>6.0</string>
+	<key>CFBundleName</key>
+	<string>$(PRODUCT_NAME)</string>
+	<key>CFBundlePackageType</key>
+	<string>$(PRODUCT_BUNDLE_PACKAGE_TYPE)</string>
+	<key>CFBundleShortVersionString</key>
+	<string>1.0</string>
+	<key>CFBundleVersion</key>
+	<string>1</string>
+	<key>LSRequiresIPhoneOS</key>
+	<true/>
+	<key>UILaunchStoryboardName</key>
+	<string>LaunchScreen</string>
+	<key>UIRequiredDeviceCapabilities</key>
+	<array>
+		<string>armv7</string>
+	</array>
+	<key>UISupportedInterfaceOrientations</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+	<key>UISupportedInterfaceOrientations~ipad</key>
+	<array>
+		<string>UIInterfaceOrientationPortrait</string>
+		<string>UIInterfaceOrientationPortraitUpsideDown</string>
+		<string>UIInterfaceOrientationLandscapeLeft</string>
+		<string>UIInterfaceOrientationLandscapeRight</string>
+	</array>
+</dict>
+</plist>
--- a/Assets.xcassets/Contents.json
+++ b/Assets.xcassets/Contents.json
@ -0,0 +1,6 @@
+{
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}
--- a/Example/Gemfile
+++ b/Example/Gemfile
@ -0,0 +1,7 @@
+source 'https://rubygems.org' do
+  gem 'cocoapods', '~> 1.11'
+  gem 'cocoapods-binary', :git => 'https://github.com/mobilecoinofficial/cocoapods-binary.git', :tag => 'v0.4.4.rev5'
+  gem 'cocoapods-repo-update'
+  gem 'cocoapods-keys'
+  gem 'fastlane'
+end
--- a/Example/Gemfile.lock
+++ b/Example/Gemfile.lock
@ -0,0 +1,306 @@
+GIT
+  remote: https://github.com/mobilecoinofficial/cocoapods-binary.git
+  revision: 748a64cc890cfaee59cdd67e80d9ade82b1b179b
+  tag: v0.4.4.rev5
+  specs:
+    cocoapods-binary (0.4.4)
+      cocoapods (>= 1.5.0, < 2.0)
+      fourflusher (~> 2.0)
+      xcpretty (~> 0.3.0)
+
+GEM
+  specs:
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    CFPropertyList (3.0.4)
+      rexml
+    RubyInline (3.12.5)
+      ZenTest (~> 4.3)
+    ZenTest (4.12.0)
+    activesupport (6.1.4.1)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+      zeitwerk (~> 2.3)
+    addressable (2.8.0)
+      public_suffix (>= 2.0.2, < 5.0)
+    algoliasearch (1.27.5)
+      httpclient (~> 2.8, >= 2.8.3)
+      json (>= 1.5.1)
+    artifactory (3.0.15)
+    atomos (0.1.3)
+    aws-eventstream (1.2.0)
+    aws-partitions (1.520.0)
+    aws-sdk-core (3.121.3)
+      aws-eventstream (~> 1, >= 1.0.2)
+      aws-partitions (~> 1, >= 1.239.0)
+      aws-sigv4 (~> 1.1)
+      jmespath (~> 1.0)
+    aws-sdk-kms (1.50.0)
+      aws-sdk-core (~> 3, >= 3.121.2)
+      aws-sigv4 (~> 1.1)
+    aws-sdk-s3 (1.104.0)
+      aws-sdk-core (~> 3, >= 3.121.2)
+      aws-sdk-kms (~> 1)
+      aws-sigv4 (~> 1.4)
+    aws-sigv4 (1.4.0)
+      aws-eventstream (~> 1, >= 1.0.2)
+    babosa (1.0.4)
+    claide (1.0.3)
+    cocoapods (1.11.2)
+      addressable (~> 2.8)
+      claide (>= 1.0.2, < 2.0)
+      cocoapods-core (= 1.11.2)
+      cocoapods-deintegrate (>= 1.0.3, < 2.0)
+      cocoapods-downloader (>= 1.4.0, < 2.0)
+      cocoapods-plugins (>= 1.0.0, < 2.0)
+      cocoapods-search (>= 1.0.0, < 2.0)
+      cocoapods-trunk (>= 1.4.0, < 2.0)
+      cocoapods-try (>= 1.1.0, < 2.0)
+      colored2 (~> 3.1)
+      escape (~> 0.0.4)
+      fourflusher (>= 2.3.0, < 3.0)
+      gh_inspector (~> 1.0)
+      molinillo (~> 0.8.0)
+      nap (~> 1.0)
+      ruby-macho (>= 1.0, < 3.0)
+      xcodeproj (>= 1.21.0, < 2.0)
+    cocoapods-core (1.11.2)
+      activesupport (>= 5.0, < 7)
+      addressable (~> 2.8)
+      algoliasearch (~> 1.0)
+      concurrent-ruby (~> 1.1)
+      fuzzy_match (~> 2.0.4)
+      nap (~> 1.0)
+      netrc (~> 0.11)
+      public_suffix (~> 4.0)
+      typhoeus (~> 1.0)
+    cocoapods-deintegrate (1.0.5)
+    cocoapods-downloader (1.5.1)
+    cocoapods-keys (2.2.1)
+      dotenv
+      osx_keychain
+    cocoapods-plugins (1.0.0)
+      nap
+    cocoapods-repo-update (0.0.4)
+      cocoapods (~> 1.0, >= 1.3.0)
+    cocoapods-search (1.0.1)
+    cocoapods-trunk (1.6.0)
+      nap (>= 0.8, < 2.0)
+      netrc (~> 0.11)
+    cocoapods-try (1.2.0)
+    colored (1.2)
+    colored2 (3.1.2)
+    commander (4.6.0)
+      highline (~> 2.0.0)
+    concurrent-ruby (1.1.9)
+    declarative (0.0.20)
+    digest-crc (0.6.4)
+      rake (>= 12.0.0, < 14.0.0)
+    domain_name (0.5.20190701)
+      unf (>= 0.0.5, < 1.0.0)
+    dotenv (2.7.6)
+    emoji_regex (3.2.3)
+    escape (0.0.4)
+    ethon (0.15.0)
+      ffi (>= 1.15.0)
+    excon (0.88.0)
+    faraday (1.8.0)
+      faraday-em_http (~> 1.0)
+      faraday-em_synchrony (~> 1.0)
+      faraday-excon (~> 1.1)
+      faraday-httpclient (~> 1.0.1)
+      faraday-net_http (~> 1.0)
+      faraday-net_http_persistent (~> 1.1)
+      faraday-patron (~> 1.0)
+      faraday-rack (~> 1.0)
+      multipart-post (>= 1.2, < 3)
+      ruby2_keywords (>= 0.0.4)
+    faraday-cookie_jar (0.0.7)
+      faraday (>= 0.8.0)
+      http-cookie (~> 1.0.0)
+    faraday-em_http (1.0.0)
+    faraday-em_synchrony (1.0.0)
+    faraday-excon (1.1.0)
+    faraday-httpclient (1.0.1)
+    faraday-net_http (1.0.1)
+    faraday-net_http_persistent (1.2.0)
+    faraday-patron (1.0.0)
+    faraday-rack (1.0.0)
+    faraday_middleware (1.2.0)
+      faraday (~> 1.0)
+    fastimage (2.2.5)
+    fastlane (2.197.0)
+      CFPropertyList (>= 2.3, < 4.0.0)
+      addressable (>= 2.8, < 3.0.0)
+      artifactory (~> 3.0)
+      aws-sdk-s3 (~> 1.0)
+      babosa (>= 1.0.3, < 2.0.0)
+      bundler (>= 1.12.0, < 3.0.0)
+      colored
+      commander (~> 4.6)
+      dotenv (>= 2.1.1, < 3.0.0)
+      emoji_regex (>= 0.1, < 4.0)
+      excon (>= 0.71.0, < 1.0.0)
+      faraday (~> 1.0)
+      faraday-cookie_jar (~> 0.0.6)
+      faraday_middleware (~> 1.0)
+      fastimage (>= 2.1.0, < 3.0.0)
+      gh_inspector (>= 1.1.2, < 2.0.0)
+      google-apis-androidpublisher_v3 (~> 0.3)
+      google-apis-playcustomapp_v1 (~> 0.1)
+      google-cloud-storage (~> 1.31)
+      highline (~> 2.0)
+      json (< 3.0.0)
+      jwt (>= 2.1.0, < 3)
+      mini_magick (>= 4.9.4, < 5.0.0)
+      multipart-post (~> 2.0.0)
+      naturally (~> 2.2)
+      optparse (~> 0.1.1)
+      plist (>= 3.1.0, < 4.0.0)
+      rubyzip (>= 2.0.0, < 3.0.0)
+      security (= 0.1.3)
+      simctl (~> 1.6.3)
+      terminal-notifier (>= 2.0.0, < 3.0.0)
+      terminal-table (>= 1.4.5, < 2.0.0)
+      tty-screen (>= 0.6.3, < 1.0.0)
+      tty-spinner (>= 0.8.0, < 1.0.0)
+      word_wrap (~> 1.0.0)
+      xcodeproj (>= 1.13.0, < 2.0.0)
+      xcpretty (~> 0.3.0)
+      xcpretty-travis-formatter (>= 0.0.3)
+    ffi (1.15.4)
+    fourflusher (2.3.1)
+    fuzzy_match (2.0.4)
+    gh_inspector (1.1.3)
+    google-apis-androidpublisher_v3 (0.13.0)
+      google-apis-core (>= 0.4, < 2.a)
+    google-apis-core (0.4.1)
+      addressable (~> 2.5, >= 2.5.1)
+      googleauth (>= 0.16.2, < 2.a)
+      httpclient (>= 2.8.1, < 3.a)
+      mini_mime (~> 1.0)
+      representable (~> 3.0)
+      retriable (>= 2.0, < 4.a)
+      rexml
+      webrick
+    google-apis-iamcredentials_v1 (0.8.0)
+      google-apis-core (>= 0.4, < 2.a)
+    google-apis-playcustomapp_v1 (0.6.0)
+      google-apis-core (>= 0.4, < 2.a)
+    google-apis-storage_v1 (0.9.0)
+      google-apis-core (>= 0.4, < 2.a)
+    google-cloud-core (1.6.0)
+      google-cloud-env (~> 1.0)
+      google-cloud-errors (~> 1.0)
+    google-cloud-env (1.5.0)
+      faraday (>= 0.17.3, < 2.0)
+    google-cloud-errors (1.2.0)
+    google-cloud-storage (1.34.1)
+      addressable (~> 2.5)
+      digest-crc (~> 0.4)
+      google-apis-iamcredentials_v1 (~> 0.1)
+      google-apis-storage_v1 (~> 0.1)
+      google-cloud-core (~> 1.6)
+      googleauth (>= 0.16.2, < 2.a)
+      mini_mime (~> 1.0)
+    googleauth (1.1.0)
+      faraday (>= 0.17.3, < 2.0)
+      jwt (>= 1.4, < 3.0)
+      memoist (~> 0.16)
+      multi_json (~> 1.11)
+      os (>= 0.9, < 2.0)
+      signet (>= 0.16, < 2.a)
+    highline (2.0.3)
+    http-cookie (1.0.4)
+      domain_name (~> 0.5)
+    httpclient (2.8.3)
+    i18n (1.8.10)
+      concurrent-ruby (~> 1.0)
+    jmespath (1.4.0)
+    json (2.6.1)
+    jwt (2.3.0)
+    memoist (0.16.2)
+    mini_magick (4.11.0)
+    mini_mime (1.1.2)
+    minitest (5.14.4)
+    molinillo (0.8.0)
+    multi_json (1.15.0)
+    multipart-post (2.0.0)
+    nanaimo (0.3.0)
+    nap (1.1.0)
+    naturally (2.2.1)
+    netrc (0.11.0)
+    optparse (0.1.1)
+    os (1.1.1)
+    osx_keychain (1.0.2)
+      RubyInline (~> 3)
+    plist (3.6.0)
+    public_suffix (4.0.6)
+    rake (13.0.6)
+    representable (3.1.1)
+      declarative (< 0.1.0)
+      trailblazer-option (>= 0.1.1, < 0.2.0)
+      uber (< 0.2.0)
+    retriable (3.1.2)
+    rexml (3.2.5)
+    rouge (2.0.7)
+    ruby-macho (2.5.1)
+    ruby2_keywords (0.0.5)
+    rubyzip (2.3.2)
+    security (0.1.3)
+    signet (0.16.0)
+      addressable (~> 2.8)
+      faraday (>= 0.17.3, < 2.0)
+      jwt (>= 1.5, < 3.0)
+      multi_json (~> 1.10)
+    simctl (1.6.8)
+      CFPropertyList
+      naturally
+    terminal-notifier (2.0.0)
+    terminal-table (1.8.0)
+      unicode-display_width (~> 1.1, >= 1.1.1)
+    trailblazer-option (0.1.1)
+    tty-cursor (0.7.1)
+    tty-screen (0.8.1)
+    tty-spinner (0.9.3)
+      tty-cursor (~> 0.7)
+    typhoeus (1.4.0)
+      ethon (>= 0.9.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    uber (0.1.0)
+    unf (0.1.4)
+      unf_ext
+    unf_ext (0.0.8)
+    unicode-display_width (1.8.0)
+    webrick (1.7.0)
+    word_wrap (1.0.0)
+    xcodeproj (1.21.0)
+      CFPropertyList (>= 2.3.3, < 4.0)
+      atomos (~> 0.1.3)
+      claide (>= 1.0.2, < 2.0)
+      colored2 (~> 3.1)
+      nanaimo (~> 0.3.0)
+      rexml (~> 3.2.4)
+    xcpretty (0.3.0)
+      rouge (~> 2.0.7)
+    xcpretty-travis-formatter (1.0.1)
+      xcpretty (~> 0.2, >= 0.0.7)
+    zeitwerk (2.5.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  cocoapods (~> 1.11)!
+  cocoapods-binary!
+  cocoapods-keys!
+  cocoapods-repo-update!
+  fastlane!
+
+BUNDLED WITH
+   2.2.24
--- a/Example/Makefile
+++ b/Example/Makefile
@ -0,0 +1,43 @@
+.PHONY: default
+default: setup bootstrap build test
+
+.PHONY: setup
+setup:
+	bundle install
+
+.PHONY: bootstrap
+bootstrap:
+	bundle exec pod install
+
+.PHONY: build
+build:
+	bundle exec fastlane gym \
+		--scheme "Unit Tests" \
+		--skip_archive \
+		--skip_codesigning
+	bundle exec fastlane gym \
+		--scheme "Integration Tests" \
+		--skip_archive \
+		--skip_codesigning
+	bundle exec fastlane gym \
+		--scheme "Performance Tests" \
+		--skip_archive \
+		--skip_codesigning
+
+.PHONY: test
+test:
+	bundle exec fastlane scan \
+		--scheme "Unit Tests"
+	bundle exec fastlane scan \
+		--scheme "Performance Tests"
+
+.PHONY: clean
+clean:
+	@[ ! -e test_output ] || rm -r test_output
+
+# Maintenance commands
+
+.PHONY: upgrade-deps
+upgrade-deps:
+	bundle update
+	bundle exec pod update
--- a/Example/Podfile
+++ b/Example/Podfile
@ -0,0 +1,92 @@
+source 'https://cdn.cocoapods.org/'
+
+platform :ios, '10.0'
+
+plugin 'cocoapods-repo-update'
+keep_source_code_for_prebuilt_frameworks!
+plugin 'cocoapods-keys', {
+  :project => "MobileCoin",
+  :keys => [
+    "devNetworkAuthUsername",
+    "devNetworkAuthPassword",
+    "testNetTestAccountMnemonicsCommaSeparated",
+  ]}
+
+use_frameworks!
+
+ENV['MC_ENABLE_SWIFTLINT_SCRIPT'] = '1'
+ENV['MC_ENABLE_WARN_LONG_COMPILE_TIMES'] = '1'
+
+target 'Example' do
+  pod 'MobileCoin', path: '..'
+  pod 'MobileCoin/Core', path: '..', testspecs: ['Tests', 'IntegrationTests', 'PerformanceTests']
+  # pod 'MobileCoin', podspec: '../MobileCoin.podspec'
+  # pod 'MobileCoin/Core', podspec: '../MobileCoin.podspec', testspecs: ['Tests', 'IntegrationTests']
+  # pod 'MobileCoin', git: 'https://github.com/mobilecoinofficial/MobileCoin-Swift.git'
+  # pod 'MobileCoin/Core', git: 'https://github.com/mobilecoinofficial/MobileCoin-Swift.git', testspecs: ['Tests', 'IntegrationTests']
+
+  pod 'LibMobileCoin'
+  # pod 'LibMobileCoin', path: '../Vendor/libmobilecoin-ios-artifacts'
+  # pod 'LibMobileCoin', podspec: '../Vendor/libmobilecoin-ios-artifacts/LibMobileCoin.podspec'
+  # pod 'LibMobileCoin', git: 'https://github.com/the-real-adammork/libmobilecoin-ios-artifacts.git'
+
+  pod 'gRPC-Swift'
+  pod 'SwiftProtobuf'
+  pod 'SwiftLint'
+end
+
+post_install do |installer|
+  # Enable building tests using Testable Release build configuration
+  installer.pods_project.targets.each do |target|
+    next unless target.name == 'MobileCoin'
+    target.build_configurations.each do |config|
+      next unless config.name == 'Testable Release'
+      config.build_settings['ENABLE_TESTABILITY'] = 'YES'
+    end
+  end
+
+  # Enable running performance tests on a physical device
+  installer.pods_project.targets.each do |target|
+    target.build_configurations.each do |config|
+      if target.name == 'AppHost-MobileCoin-UI-Tests'
+        config.build_settings['DEVELOPMENT_TEAM'] = '8JT9JJD9Y5'
+      elsif target.name.start_with? 'MobileCoin-UI-'
+        config.build_settings['DEVELOPMENT_TEAM'] = '8JT9JJD9Y5'
+        config.build_settings.delete('CODE_SIGN_IDENTITY[sdk=iphoneos*]')
+      end
+    end
+  end
+
+  # Bump deployment target to 9.0 for pods that explicitly specify 8.0, since 9.0 is the minimum
+  # that Xcode 12 supports.
+  installer.pods_project.targets.each do |target|
+    target.build_configurations.each do |config|
+      if Gem::Version.new(config.build_settings['IPHONEOS_DEPLOYMENT_TARGET']) < Gem::Version.new('9.0')
+        config.build_settings['IPHONEOS_DEPLOYMENT_TARGET'] = '9.0'
+      end
+    end
+  end
+
+  # Add Keys framework to Integration Tests for injecting values using cocoapods-keys
+  installer.pods_project.targets.each do |target|
+    next unless target.name == 'MobileCoin-Unit-Core-IntegrationTests'
+    installer.pods_project.targets.each do |keys_target|
+      next unless keys_target.name == 'Keys'
+      target.add_dependency(keys_target)
+    end
+    target.build_configurations.each do |config|
+      config.build_settings["FRAMEWORK_SEARCH_PATHS"] ||= "$(inherited)"
+      config.build_settings["FRAMEWORK_SEARCH_PATHS"] << ' "${PODS_CONFIGURATION_BUILD_DIR}/Keys"'
+      config.build_settings["OTHER_LDFLAGS"] ||= "$(inherited)"
+      config.build_settings["OTHER_LDFLAGS"] << ' -framework "Keys"'
+    end
+  end
+
+  # Disable bitcode on test targets
+  installer.pods_project.targets.each do |target|
+    next unless ['MobileCoin-Unit-Core-IntegrationTests', 'MobileCoin-UI-Core-PerformanceTests', 'MobileCoin-Unit-Core-Tests'].find_index(target.name) != nil
+    target.build_configurations.each do |config|
+      config.build_settings['ENABLE_BITCODE'] = 'NO'
+    end
+  end
+end
--- a/Example/Podfile.lock
+++ b/Example/Podfile.lock
@ -0,0 +1,204 @@
+PODS:
+  - _NIODataStructures (2.32.3)
+  - CGRPCZlib (1.5.0)
+  - CNIOAtomics (2.32.3)
+  - CNIOBoringSSL (2.15.1)
+  - CNIOBoringSSLShims (2.15.1):
+    - CNIOBoringSSL (= 2.15.1)
+  - CNIODarwin (2.32.3)
+  - CNIOHTTPParser (2.32.3)
+  - CNIOLinux (2.32.3)
+  - CNIOWindows (2.32.3)
+  - gRPC-Swift (1.5.0):
+    - CGRPCZlib (= 1.5.0)
+    - Logging (< 2.0.0, >= 1.4.0)
+    - SwiftNIO (< 3.0.0, >= 2.32.0)
+    - SwiftNIOExtras (< 2.0.0, >= 1.4.0)
+    - SwiftNIOHTTP2 (< 2.0.0, >= 1.18.2)
+    - SwiftNIOSSL (< 3.0.0, >= 2.14.0)
+    - SwiftNIOTransportServices (< 2.0.0, >= 1.11.1)
+    - SwiftProtobuf (< 2.0.0, >= 1.9.0)
+  - Keys (1.0.1)
+  - LibMobileCoin (1.2.0-pre3):
+    - gRPC-Swift
+    - SwiftProtobuf (~> 1.5)
+  - Logging (1.4.0)
+  - MobileCoin (1.2.0-pre2):
+    - MobileCoin/Core (= 1.2.0-pre2)
+  - MobileCoin/Core (1.2.0-pre2):
+    - gRPC-Swift
+    - LibMobileCoin (~> 1.2.0-pre3)
+    - Logging (~> 1.4)
+    - SwiftLint
+    - SwiftNIO
+    - SwiftNIOHPACK
+    - SwiftNIOHTTP1
+    - SwiftProtobuf
+  - MobileCoin/Core/IntegrationTests (1.2.0-pre2):
+    - gRPC-Swift
+    - LibMobileCoin (~> 1.2.0-pre3)
+    - Logging (~> 1.4)
+    - SwiftLint
+    - SwiftNIO
+    - SwiftNIOHPACK
+    - SwiftNIOHTTP1
+    - SwiftProtobuf
+  - MobileCoin/Core/PerformanceTests (1.2.0-pre2):
+    - gRPC-Swift
+    - LibMobileCoin (~> 1.2.0-pre3)
+    - Logging (~> 1.4)
+    - SwiftLint
+    - SwiftNIO
+    - SwiftNIOHPACK
+    - SwiftNIOHTTP1
+    - SwiftProtobuf
+  - MobileCoin/Core/Tests (1.2.0-pre2):
+    - gRPC-Swift
+    - LibMobileCoin (~> 1.2.0-pre3)
+    - Logging (~> 1.4)
+    - SwiftLint
+    - SwiftNIO
+    - SwiftNIOHPACK
+    - SwiftNIOHTTP1
+    - SwiftProtobuf
+  - SwiftLint (0.45.0)
+  - SwiftNIO (2.32.3):
+    - SwiftNIOCore (= 2.32.3)
+    - SwiftNIOEmbedded (= 2.32.3)
+    - SwiftNIOPosix (= 2.32.3)
+  - SwiftNIOConcurrencyHelpers (2.32.3):
+    - CNIOAtomics (= 2.32.3)
+  - SwiftNIOCore (2.32.3):
+    - CNIOLinux (= 2.32.3)
+    - SwiftNIOConcurrencyHelpers (= 2.32.3)
+  - SwiftNIOEmbedded (2.32.3):
+    - _NIODataStructures (= 2.32.3)
+    - SwiftNIOCore (= 2.32.3)
+  - SwiftNIOExtras (1.10.2):
+    - SwiftNIO (< 3, >= 2.32.0)
+  - SwiftNIOFoundationCompat (2.32.3):
+    - SwiftNIO (= 2.32.3)
+    - SwiftNIOCore (= 2.32.3)
+  - SwiftNIOHPACK (1.18.3):
+    - SwiftNIO (< 3, >= 2.32.0)
+    - SwiftNIOConcurrencyHelpers (< 3, >= 2.32.0)
+    - SwiftNIOCore (< 3, >= 2.32.0)
+    - SwiftNIOHTTP1 (< 3, >= 2.32.0)
+  - SwiftNIOHTTP1 (2.32.3):
+    - CNIOHTTPParser (= 2.32.3)
+    - SwiftNIO (= 2.32.3)
+    - SwiftNIOConcurrencyHelpers (= 2.32.3)
+    - SwiftNIOCore (= 2.32.3)
+  - SwiftNIOHTTP2 (1.18.3):
+    - SwiftNIO (< 3, >= 2.32.0)
+    - SwiftNIOConcurrencyHelpers (< 3, >= 2.32.0)
+    - SwiftNIOCore (< 3, >= 2.32.0)
+    - SwiftNIOHPACK (= 1.18.3)
+    - SwiftNIOHTTP1 (< 3, >= 2.32.0)
+    - SwiftNIOTLS (< 3, >= 2.32.0)
+  - SwiftNIOPosix (2.32.3):
+    - _NIODataStructures (= 2.32.3)
+    - CNIODarwin (= 2.32.3)
+    - CNIOLinux (= 2.32.3)
+    - CNIOWindows (= 2.32.3)
+    - SwiftNIOConcurrencyHelpers (= 2.32.3)
+    - SwiftNIOCore (= 2.32.3)
+  - SwiftNIOSSL (2.15.1):
+    - CNIOBoringSSL (= 2.15.1)
+    - CNIOBoringSSLShims (= 2.15.1)
+    - SwiftNIO (< 3, >= 2.32.0)
+    - SwiftNIOConcurrencyHelpers (< 3, >= 2.32.0)
+    - SwiftNIOCore (< 3, >= 2.32.0)
+    - SwiftNIOTLS (< 3, >= 2.32.0)
+  - SwiftNIOTLS (2.32.3):
+    - SwiftNIO (= 2.32.3)
+    - SwiftNIOCore (= 2.32.3)
+  - SwiftNIOTransportServices (1.11.3):
+    - SwiftNIO (< 3, >= 2.32.0)
+    - SwiftNIOConcurrencyHelpers (< 3, >= 2.32.0)
+    - SwiftNIOFoundationCompat (< 3, >= 2.32.0)
+    - SwiftNIOTLS (< 3, >= 2.32.0)
+  - SwiftProtobuf (1.18.0)
+
+DEPENDENCIES:
+  - gRPC-Swift
+  - Keys (from `Pods/CocoaPodsKeys`)
+  - LibMobileCoin
+  - MobileCoin (from `..`)
+  - MobileCoin/Core (from `..`)
+  - MobileCoin/Core/IntegrationTests (from `..`)
+  - MobileCoin/Core/PerformanceTests (from `..`)
+  - MobileCoin/Core/Tests (from `..`)
+  - SwiftLint
+  - SwiftProtobuf
+
+SPEC REPOS:
+  trunk:
+    - _NIODataStructures
+    - CGRPCZlib
+    - CNIOAtomics
+    - CNIOBoringSSL
+    - CNIOBoringSSLShims
+    - CNIODarwin
+    - CNIOHTTPParser
+    - CNIOLinux
+    - CNIOWindows
+    - gRPC-Swift
+    - LibMobileCoin
+    - Logging
+    - SwiftLint
+    - SwiftNIO
+    - SwiftNIOConcurrencyHelpers
+    - SwiftNIOCore
+    - SwiftNIOEmbedded
+    - SwiftNIOExtras
+    - SwiftNIOFoundationCompat
+    - SwiftNIOHPACK
+    - SwiftNIOHTTP1
+    - SwiftNIOHTTP2
+    - SwiftNIOPosix
+    - SwiftNIOSSL
+    - SwiftNIOTLS
+    - SwiftNIOTransportServices
+    - SwiftProtobuf
+
+EXTERNAL SOURCES:
+  Keys:
+    :path: Pods/CocoaPodsKeys
+  MobileCoin:
+    :path: ".."
+
+SPEC CHECKSUMS:
+  _NIODataStructures: e2077c7dc7c1d6c93e698c85fe04d663a17f53a4
+  CGRPCZlib: db324e4e4e71262d48faceb86b52dd7d4f71ff62
+  CNIOAtomics: 4dde57e1838a29a9b23ef91617505f34751cdbe5
+  CNIOBoringSSL: c99129423da079a9eb74bcfc7cfec41a6775cf94
+  CNIOBoringSSLShims: 902ae35fea0b6be5eefb4fdce906751886cfa46f
+  CNIODarwin: 0489511f8486443af71ff986ccd5abbc680ae713
+  CNIOHTTPParser: f7a6816f7ddbe7dfa57a74cd36dc2db2c53b56e8
+  CNIOLinux: 5921dfefbc4bbe017380b34c510855622147ea41
+  CNIOWindows: f5aa9dfb401b440a7b4c9cd911e53e981a787193
+  gRPC-Swift: 8942047451bf81413077e6b94bf4213e47b181cc
+  Keys: a576f4c9c1c641ca913a959a9c62ed3f215a8de9
+  LibMobileCoin: f3c44fb94b8647bd5cac3aedf0b1ca24f6cc7201
+  Logging: beeb016c9c80cf77042d62e83495816847ef108b
+  MobileCoin: 339e51b8739b7ea2f0519cc7bdde8c4e05c2b374
+  SwiftLint: e5c7f1fba68eccfc51509d5b2ce1699f5502e0c7
+  SwiftNIO: bb336ceef32850e9671d3fa0e0cc2b9add3b5948
+  SwiftNIOConcurrencyHelpers: ca2594e10749655f42baf5468212be83d2f94fe3
+  SwiftNIOCore: 9deed6620f80c7c82e8e2c2ffb9864495416d892
+  SwiftNIOEmbedded: b7ccf12b402dff35a5d4356990a6253621e4337d
+  SwiftNIOExtras: 70f09aa8eca3ab6baeaf1993da9c855b6e95e97f
+  SwiftNIOFoundationCompat: d3b888766e7c67354a4e4e145d38edf9586efa0c
+  SwiftNIOHPACK: e2fc784ce453bec4c058b21071e89fb7e542ac30
+  SwiftNIOHTTP1: 349a16aae363250cd49f430a9fdb93cff518adfa
+  SwiftNIOHTTP2: a0322f3dcecd949e03df65f4dac106411df0f12c
+  SwiftNIOPosix: e4988a8dcfd5a6319bde219d7a3d0acc5fbe7a89
+  SwiftNIOSSL: 7c2ddcbcbb2a8188468b7fe9c2bc6124df4b3772
+  SwiftNIOTLS: 1b8290ec775238ccc714ed842d929494df95a2c2
+  SwiftNIOTransportServices: 1fbbdb58510af3c53a838a1dbea98f18132dc952
+  SwiftProtobuf: c3c12645230d9b09c72267e0de89468c5543bd86
+
+PODFILE CHECKSUM: 46e25fe8f13c4beb3ac1e4ab1a9512960701d05d
+
+COCOAPODS: 1.11.2
--- a/Example/TestPlans/Integration
+++ b/Example/TestPlans/Integration
@ -0,0 +1,30 @@
+{
+  "configurations" : [
+    {
+      "id" : "7B8CC01D-B029-4322-84A2-F7F086835547",
+      "name" : "Configuration 1",
+      "options" : {
+
+      }
+    }
+  ],
+  "defaultOptions" : {
+
+  },
+  "testTargets" : [
+    {
+      "skippedTests" : [
+        "ConsensusConnectionIntTests\/testWrongTrustRootFails()",
+        "FogBlockConnectionIntTests\/testDoSGetBlocks()",
+        "FogBlockConnectionIntTests\/testGetBlockZero()",
+        "MobileCoinClientPublicApiIntTests\/testWrongConsensusTrustRootReturnsError()"
+      ],
+      "target" : {
+        "containerPath" : "container:Pods\/Pods.xcodeproj",
+        "identifier" : "45F542481CBFF9E786B4F9148AC9D6F2",
+        "name" : "MobileCoin-Unit-Core-IntegrationTests"
+      }
+    }
+  ],
+  "version" : 1
+}
--- a/Example/TestPlans/Performance
+++ b/Example/TestPlans/Performance
@ -0,0 +1,25 @@
+{
+  "configurations" : [
+    {
+      "id" : "98A4F1B1-FE76-43E0-BD61-A2B0B7F719FC",
+      "name" : "Configuration 1",
+      "options" : {
+
+      }
+    }
+  ],
+  "defaultOptions" : {
+    "uiTestingScreenshotsLifetime" : "keepNever",
+    "userAttachmentLifetime" : "keepNever"
+  },
+  "testTargets" : [
+    {
+      "target" : {
+        "containerPath" : "container:Pods\/Pods.xcodeproj",
+        "identifier" : "E8A0545E992AC3A0A6B313DAF029D326",
+        "name" : "MobileCoin-UI-Core-PerformanceTests"
+      }
+    }
+  ],
+  "version" : 1
+}
--- a/Example/TestPlans/Unit
+++ b/Example/TestPlans/Unit
@ -0,0 +1,24 @@
+{
+  "configurations" : [
+    {
+      "id" : "E10088A3-9143-42A3-8186-B64A2E756B6A",
+      "name" : "Configuration 1",
+      "options" : {
+
+      }
+    }
+  ],
+  "defaultOptions" : {
+
+  },
+  "testTargets" : [
+    {
+      "target" : {
+        "containerPath" : "container:Pods\/Pods.xcodeproj",
+        "identifier" : "C10663274EBBCA6839AB2898903FF5CB",
+        "name" : "MobileCoin-Unit-Core-Tests"
+      }
+    }
+  ],
+  "version" : 1
+}
--- a/4
+++ b/4
@ -0,0 +1,4 @@
+source 'https://rubygems.org' do
+  gem 'cocoapods', '~> 1.11'
+  gem 'jazzy'
+end
--- a/Gemfile.lock
+++ b/Gemfile.lock
@ -0,0 +1,121 @@
+GEM
+  specs:
+
+GEM
+  remote: https://rubygems.org/
+  specs:
+    CFPropertyList (3.0.4)
+      rexml
+    activesupport (6.1.4.1)
+      concurrent-ruby (~> 1.0, >= 1.0.2)
+      i18n (>= 1.6, < 2)
+      minitest (>= 5.1)
+      tzinfo (~> 2.0)
+      zeitwerk (~> 2.3)
+    addressable (2.8.0)
+      public_suffix (>= 2.0.2, < 5.0)
+    algoliasearch (1.27.5)
+      httpclient (~> 2.8, >= 2.8.3)
+      json (>= 1.5.1)
+    atomos (0.1.3)
+    claide (1.0.3)
+    cocoapods (1.11.2)
+      addressable (~> 2.8)
+      claide (>= 1.0.2, < 2.0)
+      cocoapods-core (= 1.11.2)
+      cocoapods-deintegrate (>= 1.0.3, < 2.0)
+      cocoapods-downloader (>= 1.4.0, < 2.0)
+      cocoapods-plugins (>= 1.0.0, < 2.0)
+      cocoapods-search (>= 1.0.0, < 2.0)
+      cocoapods-trunk (>= 1.4.0, < 2.0)
+      cocoapods-try (>= 1.1.0, < 2.0)
+      colored2 (~> 3.1)
+      escape (~> 0.0.4)
+      fourflusher (>= 2.3.0, < 3.0)
+      gh_inspector (~> 1.0)
+      molinillo (~> 0.8.0)
+      nap (~> 1.0)
+      ruby-macho (>= 1.0, < 3.0)
+      xcodeproj (>= 1.21.0, < 2.0)
+    cocoapods-core (1.11.2)
+      activesupport (>= 5.0, < 7)
+      addressable (~> 2.8)
+      algoliasearch (~> 1.0)
+      concurrent-ruby (~> 1.1)
+      fuzzy_match (~> 2.0.4)
+      nap (~> 1.0)
+      netrc (~> 0.11)
+      public_suffix (~> 4.0)
+      typhoeus (~> 1.0)
+    cocoapods-deintegrate (1.0.5)
+    cocoapods-downloader (1.5.1)
+    cocoapods-plugins (1.0.0)
+      nap
+    cocoapods-search (1.0.1)
+    cocoapods-trunk (1.6.0)
+      nap (>= 0.8, < 2.0)
+      netrc (~> 0.11)
+    cocoapods-try (1.2.0)
+    colored2 (3.1.2)
+    concurrent-ruby (1.1.9)
+    escape (0.0.4)
+    ethon (0.15.0)
+      ffi (>= 1.15.0)
+    ffi (1.15.4)
+    fourflusher (2.3.1)
+    fuzzy_match (2.0.4)
+    gh_inspector (1.1.3)
+    httpclient (2.8.3)
+    i18n (1.8.10)
+      concurrent-ruby (~> 1.0)
+    jazzy (0.14.1)
+      cocoapods (~> 1.5)
+      mustache (~> 1.1)
+      open4 (~> 1.3)
+      redcarpet (~> 3.4)
+      rexml (~> 3.2)
+      rouge (>= 2.0.6, < 4.0)
+      sassc (~> 2.1)
+      sqlite3 (~> 1.3)
+      xcinvoke (~> 0.3.0)
+    json (2.6.1)
+    liferaft (0.0.6)
+    minitest (5.14.4)
+    molinillo (0.8.0)
+    mustache (1.1.1)
+    nanaimo (0.3.0)
+    nap (1.1.0)
+    netrc (0.11.0)
+    open4 (1.3.4)
+    public_suffix (4.0.6)
+    redcarpet (3.5.1)
+    rexml (3.2.5)
+    rouge (3.26.1)
+    ruby-macho (2.5.1)
+    sassc (2.4.0)
+      ffi (~> 1.9)
+    sqlite3 (1.4.2)
+    typhoeus (1.4.0)
+      ethon (>= 0.9.0)
+    tzinfo (2.0.4)
+      concurrent-ruby (~> 1.0)
+    xcinvoke (0.3.0)
+      liferaft (~> 0.0.6)
+    xcodeproj (1.21.0)
+      CFPropertyList (>= 2.3.3, < 4.0)
+      atomos (~> 0.1.3)
+      claide (>= 1.0.2, < 2.0)
+      colored2 (~> 3.1)
+      nanaimo (~> 0.3.0)
+      rexml (~> 3.2.4)
+    zeitwerk (2.5.1)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  cocoapods (~> 1.11)!
+  jazzy!
+
+BUNDLED WITH
+   2.2.24
--- a/Glue/MobileCoinMinimal.m
+++ b/Glue/MobileCoinMinimal.m
@ -1,7 +0,0 @@
-
-#import <CocoaLumberjack/CocoaLumberjack.h>
-#ifdef DEBUG
-static const NSUInteger ddLogLevel = DDLogLevelAll;
-#else
-static const NSUInteger ddLogLevel = DDLogLevelInfo;
-#endif
--- a/Glue/MobileCoinMinimal.swift
+++ b/Glue/MobileCoinMinimal.swift
@ -1,34 +0,0 @@
-
-
-import Foundation
-
-public enum MobileCoinMinimalError: Error {
-    case invalidReceipt
-}
-
-// MARK: -
-
-public class MobileCoinMinimal {
-    
-    public static func txOutPublicKey(forReceiptData serializedData: Data) throws -> Data {
-        guard let proto = try? External_Receipt(serializedData: serializedData) else {
-            logger.warning(
-                "External_Receipt deserialization failed. serializedData: " +
-                "\(redacting: serializedData.base64EncodedString())",
-                logFunction: false)
-            throw MobileCoinMinimalError.invalidReceipt
-        }
-        let txOutPublicKey = proto.publicKey.data
-        return txOutPublicKey
-    }
-
-    public static func isValidMobileCoinPublicAddress(_ serializedData: Data) -> Bool {
-        guard let proto = try? External_PublicAddress(serializedData: serializedData) else {
-            logger.warning("External_PublicAddress deserialization failed. serializedData: " +
-                           "\(redacting: serializedData.base64EncodedString())")
-            return false
-        }
-        return true
-    }
-}
-
--- a/LibMobileCoin/Sources/Generated/Proto/external.pb.swift
+++ b/LibMobileCoin/Sources/Generated/Proto/external.pb.swift
--- a/104
+++ b/104
@ -0,0 +1,104 @@
+.PHONY: default
+default: setup bootstrap build test
+
+# Commands
+
+.PHONY: setup
+setup:
+	bundle install
+	@$(MAKE) --directory=Example setup
+
+.PHONY: bootstrap
+bootstrap:
+	@$(MAKE) --directory=Example bootstrap
+
+.PHONY: build
+build:
+	@$(MAKE) --directory=Example build
+
+.PHONY: test
+test:
+	@$(MAKE) --directory=Example test
+
+.PHONY: clean
+clean: clean-docs
+	@$(MAKE) --directory=Example clean
+
+.PHONY: lint
+lint: swiftlint
+
+.PHONY: lint-all
+lint-all: lint lint-circleci lint-podspec lint-docs
+
+.PHONY: publish
+publish: tag-release publish-podspec
+
+# Release
+
+.PHONY: tag-release
+tag-release:
+	VERSION="$$(bundle exec pod ipc spec MobileCoin.podspec | jq -r '.version')" && \
+		git tag "v$$VERSION" && \
+		git push git@github.com:mobilecoinofficial/MobileCoin-Swift.git "refs/tags/v$$VERSION"
+
+# MobileCoin pod
+
+.PHONY: lint-podspec
+lint-podspec:
+	bundle exec pod spec lint MobileCoin.podspec --skip-tests
+
+.PHONY: publish-podspec
+publish-podspec:
+	bundle exec pod trunk push MobileCoin.podspec --skip-tests
+
+# CircleCI
+
+.PHONY: install-circleci
+install-circleci:
+	brew install circleci
+
+.PHONY: lint-circleci
+lint-circleci:
+	@command -v circleci >/dev/null || $(MAKE) install-circleci
+	circleci config validate
+
+# Documentation
+
+.PHONY: docs
+docs:
+	bundle exec jazzy
+
+.PHONY: clean-docs
+clean-docs:
+	@[ ! -e docs ] || rm -r docs
+
+.PHONY: lint-docs
+lint-docs:
+	@[ -e docs ] || $(MAKE) docs
+
+	@# Check that there are no categories that start with `Other `, since that signifies that a new public
+	@# type was added but was not added to a category in `.jazzy.yaml`
+	@[[ "$$( \
+		name_regex='^Other (?:Classes|Constants|Enumerations|Extensions|Functions|Protocols|Structures|Type Aliases|Type Definitions)$$'; \
+		cat docs/search.json | jq ".[] \
+			| select(has(\"parent_name\") | not) \
+			| select(has(\"name\")) \
+			| select(.name | test(\"$$name_regex\"))" \
+	)" == "" ]] || { echo 'Error: Found one or more public types not categorized in jazzy.'; exit 1; }
+
+# Swiftlint
+
+.PHONY: autocorrect
+autocorrect:
+	@PATH="./Example/Pods/SwiftLint:$$PATH" swiftlint autocorrect
+
+.PHONY: swiftlint
+swiftlint:
+	@PATH="./Example/Pods/SwiftLint:$$PATH" swiftlint
+
+# Maintenance
+
+.PHONY: upgrade-deps
+upgrade-deps:
+	bundle update
+	$(MAKE) -C Example upgrade-deps
--- a/MobileCoinMinimal.podspec
+++ b/MobileCoinMinimal.podspec
@ -2,7 +2,7 @@ Pod::Spec.new do |s|

  # ―――  Spec Metadata  ―――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #

-  s.name         = "MobileCoinMinimal"
+  s.name         = "MobileCoin"
  s.version      = "1.2.0-pre2"
  s.summary      = "A library for communicating with MobileCoin network"

@ -25,26 +25,48 @@ Pod::Spec.new do |s|

  # ――― Subspecs ――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #

-	s.source_files = [
-		"Sources/**/*.{h,m,swift}",
-		"LibMobileCoin/**/*.{h,m,swift}",
-		"Glue/**/*.{h,m,swift}",
-	]
+  s.default_subspec = "Core"
+
+  s.subspec "Core" do |subspec|
+    subspec.source_files = [
+      "Sources/**/*.{h,m,swift}",
+    ]
+
+    subspec.dependency "LibMobileCoin", "~> 1.2.0-pre3"
+
+    subspec.dependency "gRPC-Swift"
+    subspec.dependency "Logging", "~> 1.4"
+    subspec.dependency "SwiftNIO"
+    subspec.dependency "SwiftNIOHPACK"
+    subspec.dependency "SwiftNIOHTTP1"
+    subspec.dependency "SwiftProtobuf"
+
+    subspec.test_spec do |test_spec|
+      test_spec.source_files = "Tests/{Unit,Common}/**/*.swift"
+      test_spec.resources = [
+        "Tests/Common/FixtureData/**/*",
+        "Vendor/libmobilecoin-ios-artifacts/Vendor/mobilecoin/test-vectors/vectors/**/*",
+      ]
+    end
+
+    subspec.test_spec 'IntegrationTests' do |test_spec|
+      test_spec.source_files = "Tests/{Integration,Common}/**/*.swift"
+      test_spec.resource = "Tests/Common/FixtureData/**/*"
+    end
+
+    subspec.test_spec 'PerformanceTests' do |test_spec|
+      test_spec.source_files = "Tests/{Performance,Common}/**/*.swift"
+
+      test_spec.test_type = :ui
+      test_spec.requires_app_host = true
+    end
+
+    unless ENV["MC_ENABLE_SWIFTLINT_SCRIPT"].nil?
+      subspec.dependency 'SwiftLint'
+    end
+  end

-	s.dependency "Logging", "~> 1.4"
-	s.dependency "SwiftProtobuf"
-	s.dependency "CocoaLumberjack"

-	# s.test_spec do |test_spec|
-	s.test_spec 'Tests' do |test_spec|
-		test_spec.source_files = [
-			'Tests/**/*.{h,m,swift}',
-			'TestGlue/**/*.{h,m,swift}',
-		]
-		# test_spec.resources = 'Tests/**/*.{json,encrypted,webp}'
-		test_spec.resources = 'Tests/**/*.*'
-	end
-  	
  # ――― Project Settings ――――――――――――――――――――――――――――――――――――――――――――――――――――――――― #

  s.swift_version = "5.2"
@ -70,5 +92,23 @@ Pod::Spec.new do |s|
  end

  s.pod_target_xcconfig = pod_target_xcconfig
+
+  unless ENV["MC_ENABLE_SWIFTLINT_SCRIPT"].nil?
+    s.script_phases = [
+      {
+        :name => "Run SwiftLint",
+        :execution_position => :any,
+        :script => <<~'EOS'
+          SWIFTLINT="${PODS_ROOT}/SwiftLint/swiftlint"
+          if which ${SWIFTLINT} >/dev/null; then
+            cd "${PODS_TARGET_SRCROOT}"
+            ${SWIFTLINT}
+          else
+            echo "warning: SwiftLint not installed, run \`pod install\`"
+          fi
+        EOS
+      },
+    ]
+  end
 end

--- a/Sources/Account/Account+BalanceUpdater.swift
+++ b/Sources/Account/Account+BalanceUpdater.swift
@ -0,0 +1,128 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+extension Account {
+    struct BalanceUpdater {
+        private let serialQueue: DispatchQueue
+        private let account: ReadWriteDispatchLock<Account>
+        private let txOutFetcher: FogView.TxOutFetcher
+        private let viewKeyScanner: FogViewKeyScanner
+        private let fogKeyImageChecker: FogKeyImageChecker
+
+        init(
+            account: ReadWriteDispatchLock<Account>,
+            fogViewService: FogViewService,
+            fogKeyImageService: FogKeyImageService,
+            fogBlockService: FogBlockService,
+            fogQueryScalingStrategy: FogQueryScalingStrategy,
+            targetQueue: DispatchQueue?
+        ) {
+            self.serialQueue = DispatchQueue(
+                label: "com.mobilecoin.\(Account.self).\(Self.self)",
+                target: targetQueue)
+            self.account = account
+            self.txOutFetcher = FogView.TxOutFetcher(
+                fogView: account.mapLockWithoutLocking { $0.fogView },
+                accountKey: account.accessWithoutLocking.accountKey,
+                fogViewService: fogViewService,
+                fogQueryScalingStrategy: fogQueryScalingStrategy,
+                targetQueue: targetQueue)
+            self.viewKeyScanner = FogViewKeyScanner(
+                accountKey: account.accessWithoutLocking.accountKey,
+                fogBlockService: fogBlockService)
+            self.fogKeyImageChecker = FogKeyImageChecker(
+                fogKeyImageService: fogKeyImageService,
+                targetQueue: targetQueue)
+        }
+
+        func updateBalance(completion: @escaping (Result<Balance, ConnectionError>) -> Void) {
+            logger.info("Updating balance...", logFunction: false)
+            checkForNewTxOuts {
+                guard $0.successOr(completion: completion) != nil else {
+                    logger.warning(
+                        "Failed to update balance: checkForNewTxOuts error: \($0)",
+                        logFunction: false)
+                    return
+                }
+
+                self.checkForSpentTxOuts {
+                    guard $0.successOr(completion: completion) != nil else {
+                        logger.warning(
+                            "Failed to update balance: checkForSpentTxOuts error: \($0)",
+                            logFunction: false)
+                        return
+                    }
+
+                    let balance = self.account.readSync { $0.cachedBalance }
+
+                    logger.info(
+                        "Balance update successful. balance: \(redacting: balance)",
+                        logFunction: false)
+                    completion(.success(balance))
+                }
+            }
+        }
+
+        func checkForNewTxOuts(completion: @escaping (Result<(), ConnectionError>) -> Void) {
+            checkForNewFogViewTxOuts {
+                guard $0.successOr(completion: completion) != nil else { return }
+
+                self.viewKeyScanUnscannedMissedBlocks(completion: completion)
+            }
+        }
+
+        func checkForNewFogViewTxOuts(completion: @escaping (Result<(), ConnectionError>) -> Void) {
+            txOutFetcher.fetchTxOuts(partialResultsWithWriteLock: { newTxOuts in
+                logger.info(
+                    "Found \(redacting: newTxOuts.count) new TxOuts using Fog View",
+                    logFunction: false)
+                let account = self.account.accessWithoutLocking
+                account.addTxOuts(newTxOuts)
+            }, completion: completion)
+        }
+
+        func viewKeyScanUnscannedMissedBlocks(
+            completion: @escaping (Result<(), ConnectionError>) -> Void
+        ) {
+            let unscannedBlockRanges = account.readSync { $0.unscannedMissedBlocksRanges }
+            guard !unscannedBlockRanges.isEmpty else {
+                logger.debug("0 unscanned missed blocks, skipping.", logFunction: false)
+                serialQueue.async {
+                    completion(.success(()))
+                }
+                return
+            }
+            viewKeyScanner.viewKeyScanBlocks(blockRanges: unscannedBlockRanges) {
+                completion($0.map { foundTxOuts in
+                    self.account.writeSync {
+                        $0.addViewKeyScanResults(
+                            scannedBlockRanges: unscannedBlockRanges,
+                            foundTxOuts: foundTxOuts)
+                    }
+                })
+            }
+        }
+
+        func checkForSpentTxOuts(completion: @escaping (Result<(), ConnectionError>) -> Void) {
+            let keyImageTrackers = account.mapLock { account in
+                account.allTxOutTrackers.filter { !$0.isSpent }.map { $0.keyImageTracker }
+            }
+            let queries = keyImageTrackers.readSync {
+                $0.map { ($0.keyImage, $0.nextKeyImageQueryBlockIndex) }
+            }
+            fogKeyImageChecker.checkKeyImages(keyImageQueries: queries) {
+                completion($0.map { statuses in
+                    keyImageTrackers.writeSync { keyImageTrackers in
+                        for (tracker, status) in zip(keyImageTrackers, statuses) {
+                            tracker.spentStatus = status
+                        }
+                    }
+                })
+            }
+        }
+    }
+}
--- a/Sources/Account/Account+TransactionEstimator.swift
+++ b/Sources/Account/Account+TransactionEstimator.swift
@ -0,0 +1,231 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable closure_body_length
+
+import Foundation
+
+extension Account {
+    struct TransactionEstimator {
+        private let serialQueue: DispatchQueue
+        private let account: ReadWriteDispatchLock<Account>
+        private let feeFetcher: BlockchainFeeFetcher
+        private let txOutSelector: TxOutSelector
+
+        init(
+            account: ReadWriteDispatchLock<Account>,
+            feeFetcher: BlockchainFeeFetcher,
+            txOutSelectionStrategy: TxOutSelectionStrategy,
+            targetQueue: DispatchQueue?
+        ) {
+            self.serialQueue = DispatchQueue(
+                label: "com.mobilecoin.\(Account.self).\(Self.self))",
+                target: targetQueue)
+            self.account = account
+            self.feeFetcher = feeFetcher
+            self.txOutSelector = TxOutSelector(txOutSelectionStrategy: txOutSelectionStrategy)
+        }
+
+        func amountTransferable(
+            feeLevel: FeeLevel,
+            completion: @escaping (Result<UInt64, BalanceTransferEstimationFetcherError>) -> Void
+        ) {
+            feeFetcher.feeStrategy(for: feeLevel) {
+                completion($0.mapError { .connectionError($0) }
+                    .flatMap { feeStrategy in
+                        let txOuts = self.account.readSync { $0.unspentTxOuts }
+                        logger.info(
+                            "Calculating amountTransferable. feeLevel: \(feeLevel), " +
+                                "unspentTxOutValues: \(redacting: txOuts.map { $0.value })",
+                            logFunction: false)
+                        return self.txOutSelector
+                            .amountTransferable(feeStrategy: feeStrategy, txOuts: txOuts)
+                            .mapError {
+                                switch $0 {
+                                case .feeExceedsBalance(let reason):
+                                    return .feeExceedsBalance(reason)
+                                case .balanceOverflow(let reason):
+                                    return .balanceOverflow(reason)
+                                }
+                            }
+                            .map {
+                                logger.info(
+                                    "amountTransferable: \(redacting: $0)",
+                                    logFunction: false)
+                                return $0
+                            }
+                    })
+            }
+        }
+
+        func estimateTotalFee(
+            toSendAmount amount: UInt64,
+            feeLevel: FeeLevel,
+            completion: @escaping (Result<UInt64, TransactionEstimationFetcherError>) -> Void
+        ) {
+            guard amount > 0 else {
+                let errorMessage = "estimateTotalFee failure: Cannot spend 0 MOB"
+                logger.error(errorMessage, logFunction: false)
+                serialQueue.async {
+                    completion(.failure(.invalidInput(errorMessage)))
+                }
+                return
+            }
+
+            feeFetcher.feeStrategy(for: feeLevel) {
+                completion($0.mapError { .connectionError($0) }
+                    .flatMap { feeStrategy in
+                        let txOuts = self.account.readSync { $0.unspentTxOuts }
+                        logger.info(
+                            "Estimating total fee: amount: \(redacting: amount), feeLevel: " +
+                                "\(feeLevel), unspentTxOutValues: " +
+                                "\(redacting: txOuts.map { $0.value })",
+                            logFunction: false)
+                        return self.txOutSelector
+                            .estimateTotalFee(
+                                toSendAmount: amount,
+                                feeStrategy: feeStrategy,
+                                txOuts: txOuts)
+                            .mapError { _ in
+                                TransactionEstimationFetcherError.insufficientBalance()
+                            }
+                            .map {
+                                logger.info(
+                                    "estimateTotalFee: \(redacting: $0.totalFee), " +
+                                        "requiresDefrag: \($0.requiresDefrag)",
+                                    logFunction: false)
+                                return $0.totalFee
+                            }
+                    })
+            }
+        }
+
+        func requiresDefragmentation(
+            toSendAmount amount: UInt64,
+            feeLevel: FeeLevel,
+            completion: @escaping (Result<Bool, TransactionEstimationFetcherError>) -> Void
+        ) {
+            guard amount > 0 else {
+                let errorMessage = "requiresDefragmentation failure: Cannot spend 0 MOB"
+                logger.error(errorMessage, logFunction: false)
+                serialQueue.async {
+                    completion(.failure(.invalidInput(errorMessage)))
+                }
+                return
+            }
+
+            feeFetcher.feeStrategy(for: feeLevel) {
+                completion($0.mapError { .connectionError($0) }
+                    .flatMap { feeStrategy in
+                        let txOuts = self.account.readSync { $0.unspentTxOuts }
+                        logger.info(
+                            "Calculation defragmentation required: amount: \(redacting: amount), " +
+                                "feeLevel: \(feeLevel), unspentTxOutValues: " +
+                                "\(redacting: txOuts.map { $0.value })",
+                            logFunction: false)
+                        return self.txOutSelector
+                            .estimateTotalFee(
+                                toSendAmount: amount,
+                                feeStrategy: feeStrategy,
+                                txOuts: txOuts)
+                            .mapError { _ in
+                                TransactionEstimationFetcherError.insufficientBalance()
+                            }
+                            .map {
+                                logger.info(
+                                    "requiresDefragmentation: \($0.requiresDefrag), totalFee: " +
+                                        "\(redacting: $0.totalFee)",
+                                logFunction: false)
+                                return $0.requiresDefrag
+                            }
+                    })
+            }
+        }
+    }
+}
+
+extension Account.TransactionEstimator {
+    @available(*, deprecated, message: "Use amountTransferable(feeLevel:completion:) instead")
+    func amountTransferable(feeLevel: FeeLevel)
+        -> Result<UInt64, BalanceTransferEstimationError>
+    {
+        let feeStrategy = feeLevel.defaultFeeStrategy
+        let txOuts = account.readSync { $0.unspentTxOuts }
+        logger.info(
+            "Calculating amountTransferable. feeLevel: \(feeLevel), unspentTxOutValues: " +
+                "\(redacting: txOuts.map { $0.value })",
+            logFunction: false)
+        return txOutSelector.amountTransferable(feeStrategy: feeStrategy, txOuts: txOuts)
+            .mapError {
+                switch $0 {
+                case .feeExceedsBalance(let reason):
+                    return .feeExceedsBalance(reason)
+                case .balanceOverflow(let reason):
+                    return .balanceOverflow(reason)
+                }
+            }
+            .map {
+                logger.info("amountTransferable: \(redacting: $0)", logFunction: false)
+                return $0
+            }
+    }
+
+    @available(*, deprecated, message:
+        "Use estimateTotalFee(toSendAmount:feeLevel:completion:) instead")
+    func estimateTotalFee(toSendAmount amount: UInt64, feeLevel: FeeLevel)
+        -> Result<UInt64, TransactionEstimationError>
+    {
+        guard amount > 0 else {
+            let errorMessage = "estimateTotalFee failure: Cannot spend 0 MOB"
+            logger.error(errorMessage, logFunction: false)
+            return .failure(.invalidInput(errorMessage))
+        }
+
+        let feeStrategy = feeLevel.defaultFeeStrategy
+        let txOuts = account.readSync { $0.unspentTxOuts }
+        logger.info(
+            "Estimating total fee: amount: \(redacting: amount), feeLevel: \(feeLevel), " +
+                "unspentTxOutValues: \(redacting: txOuts.map { $0.value })",
+            logFunction: false)
+        return txOutSelector
+            .estimateTotalFee(toSendAmount: amount, feeStrategy: feeStrategy, txOuts: txOuts)
+            .mapError { _ -> TransactionEstimationError in .insufficientBalance() }
+            .map {
+                logger.info(
+                    "estimateTotalFee: \(redacting: $0.totalFee), requiresDefrag: " +
+                        "\($0.requiresDefrag)",
+                    logFunction: false)
+                return $0.totalFee
+            }
+    }
+
+    @available(*, deprecated, message:
+        "Use requiresDefragmentation(toSendAmount:feeLevel:completion:) instead")
+    func requiresDefragmentation(toSendAmount amount: UInt64, feeLevel: FeeLevel)
+        -> Result<Bool, TransactionEstimationError>
+    {
+        guard amount > 0 else {
+            let errorMessage = "requiresDefragmentation failure: Cannot spend 0 MOB"
+            logger.error(errorMessage, logFunction: false)
+            return .failure(.invalidInput(errorMessage))
+        }
+
+        let feeStrategy = feeLevel.defaultFeeStrategy
+        let txOuts = account.readSync { $0.unspentTxOuts }
+        logger.info(
+            "Calculation defragmentation required: amount: \(redacting: amount), feeLevel: " +
+                "\(feeLevel), unspentTxOutValues: \(redacting: txOuts.map { $0.value })",
+            logFunction: false)
+        return txOutSelector
+            .estimateTotalFee(toSendAmount: amount, feeStrategy: feeStrategy, txOuts: txOuts)
+            .mapError { _ -> TransactionEstimationError in .insufficientBalance() }
+            .map {
+                logger.info(
+                    "requiresDefragmentation: \($0.requiresDefrag), totalFee: " +
+                        "\(redacting: $0.totalFee)",
+                logFunction: false)
+                return $0.requiresDefrag
+            }
+    }
+}
--- a/Sources/Account/Account+TransactionOperations.swift
+++ b/Sources/Account/Account+TransactionOperations.swift
@ -0,0 +1,222 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable closure_body_length function_body_length multiline_arguments
+
+import Foundation
+
+extension Account {
+    struct TransactionOperations {
+        private let serialQueue: DispatchQueue
+        private let account: ReadWriteDispatchLock<Account>
+        private let feeFetcher: BlockchainFeeFetcher
+        private let txOutSelector: TxOutSelector
+        private let transactionPreparer: TransactionPreparer
+
+        init(
+            account: ReadWriteDispatchLock<Account>,
+            fogMerkleProofService: FogMerkleProofService,
+            fogResolverManager: FogResolverManager,
+            feeFetcher: BlockchainFeeFetcher,
+            txOutSelectionStrategy: TxOutSelectionStrategy,
+            mixinSelectionStrategy: MixinSelectionStrategy,
+            targetQueue: DispatchQueue?
+        ) {
+            self.serialQueue = DispatchQueue(
+                label: "com.mobilecoin.\(Account.self).\(Self.self))",
+                target: targetQueue)
+            self.account = account
+            self.feeFetcher = feeFetcher
+            self.txOutSelector = TxOutSelector(txOutSelectionStrategy: txOutSelectionStrategy)
+            self.transactionPreparer = TransactionPreparer(
+                accountKey: account.accessWithoutLocking.accountKey,
+                fogMerkleProofService: fogMerkleProofService,
+                fogResolverManager: fogResolverManager,
+                mixinSelectionStrategy: mixinSelectionStrategy,
+                targetQueue: targetQueue)
+        }
+
+        func prepareTransaction(
+            to recipient: PublicAddress,
+            amount: UInt64,
+            fee: UInt64,
+            completion: @escaping (
+                Result<(transaction: Transaction, receipt: Receipt), TransactionPreparationError>
+            ) -> Void
+        ) {
+            guard amount > 0 else {
+                let errorMessage = "prepareTransactionWithFee failure: Cannot spend 0 MOB"
+                logger.error(errorMessage, logFunction: false)
+                serialQueue.async {
+                    completion(.failure(.invalidInput(errorMessage)))
+                }
+                return
+            }
+
+            let (unspentTxOuts, ledgerBlockCount) =
+                account.readSync { ($0.unspentTxOuts, $0.knowableBlockCount) }
+            logger.info(
+                "Preparing transaction with provided fee... recipient: \(redacting: recipient), " +
+                    "amount: \(redacting: amount), fee: \(redacting: fee), unspentTxOutValues: " +
+                    "\(redacting: unspentTxOuts.map { $0.value })",
+                logFunction: false)
+            switch txOutSelector
+                .selectTransactionInputs(amount: amount, fee: fee, fromTxOuts: unspentTxOuts)
+                .mapError({ error -> TransactionPreparationError in
+                    switch error {
+                    case .insufficientTxOuts:
+                        return .insufficientBalance()
+                    case .defragmentationRequired:
+                        return .defragmentationRequired()
+                    }
+                })
+            {
+            case .success(let txOutsToSpend):
+                logger.info(
+                    "Transaction prepared with fee. txOutsToSpend: " +
+                        "0x\(redacting: txOutsToSpend.map { $0.publicKey.hexEncodedString() })",
+                    logFunction: false)
+                let tombstoneBlockIndex = ledgerBlockCount + 50
+                transactionPreparer.prepareTransaction(
+                    inputs: txOutsToSpend,
+                    recipient: recipient,
+                    amount: amount,
+                    fee: fee,
+                    tombstoneBlockIndex: tombstoneBlockIndex,
+                    completion: completion)
+            case .failure(let error):
+                logger.info("prepareTransactionWithFee failure: \(error)", logFunction: false)
+                serialQueue.async {
+                    completion(.failure(error))
+                }
+            }
+        }
+
+        func prepareTransaction(
+            to recipient: PublicAddress,
+            amount: UInt64,
+            feeLevel: FeeLevel,
+            completion: @escaping (
+                Result<(transaction: Transaction, receipt: Receipt), TransactionPreparationError>
+            ) -> Void
+        ) {
+            guard amount > 0 else {
+                let errorMessage = "prepareTransactionWithFeeLevel failure: Cannot spend 0 MOB"
+                logger.error(errorMessage, logFunction: false)
+                serialQueue.async {
+                    completion(.failure(.invalidInput(errorMessage)))
+                }
+                return
+            }
+
+            feeFetcher.feeStrategy(for: feeLevel) {
+                switch $0 {
+                case .success(let feeStrategy):
+                    let (unspentTxOuts, ledgerBlockCount) =
+                        self.account.readSync { ($0.unspentTxOuts, $0.knowableBlockCount) }
+                    logger.info(
+                        "Preparing transaction with fee level... recipient: " +
+                            "\(redacting: recipient), amount: \(redacting: amount), feeLevel: " +
+                            "\(feeLevel), unspentTxOutValues: " +
+                            "\(redacting: unspentTxOuts.map { $0.value })",
+                        logFunction: false)
+                    switch self.txOutSelector
+                        .selectTransactionInputs(
+                            amount: amount,
+                            feeStrategy: feeStrategy,
+                            fromTxOuts: unspentTxOuts)
+                        .mapError({ error -> TransactionPreparationError in
+                            switch error {
+                            case .insufficientTxOuts:
+                                return .insufficientBalance()
+                            case .defragmentationRequired:
+                                return .defragmentationRequired()
+                            }
+                        })
+                    {
+                    case .success(let (inputs: inputs, fee: fee)):
+                        logger.info(
+                            "Transaction prepared with fee level. fee: \(redacting: fee)",
+                            logFunction: false)
+                        let tombstoneBlockIndex = ledgerBlockCount + 50
+                        self.transactionPreparer.prepareTransaction(
+                            inputs: inputs,
+                            recipient: recipient,
+                            amount: amount,
+                            fee: fee,
+                            tombstoneBlockIndex: tombstoneBlockIndex,
+                            completion: completion)
+                    case .failure(let error):
+                        logger.info(
+                            "prepareTransactionWithFeeLevel failure: \(error)",
+                            logFunction: false)
+                        completion(.failure(error))
+                    }
+                case .failure(let connectionError):
+                    logger.info("failure - error: \(connectionError)")
+                    completion(.failure(.connectionError(connectionError)))
+                }
+            }
+        }
+
+        func prepareDefragmentationStepTransactions(
+            toSendAmount amountToSend: UInt64,
+            feeLevel: FeeLevel,
+            completion: @escaping (Result<[Transaction], DefragTransactionPreparationError>) -> Void
+        ) {
+            guard amountToSend > 0 else {
+                let errorMessage =
+                    "prepareDefragmentationStepTransactions failure: Cannot spend 0 MOB"
+                logger.error(errorMessage, logFunction: false)
+                serialQueue.async {
+                    completion(.failure(.invalidInput(errorMessage)))
+                }
+                return
+            }
+
+            feeFetcher.feeStrategy(for: feeLevel) {
+                switch $0 {
+                case .success(let feeStrategy):
+                    let (unspentTxOuts, ledgerBlockCount) =
+                        self.account.readSync { ($0.unspentTxOuts, $0.knowableBlockCount) }
+                    logger.info(
+                        "Preparing defragmentation step transactions... amountToSend: " +
+                            "\(redacting: amountToSend), feeLevel: \(feeLevel), " +
+                            "unspentTxOutValues: \(redacting: unspentTxOuts.map { $0.value })",
+                        logFunction: false)
+                    switch self.txOutSelector.selectInputsForDefragTransactions(
+                        toSendAmount: amountToSend,
+                        feeStrategy: feeStrategy,
+                        fromTxOuts: unspentTxOuts)
+                    {
+                    case .success(let defragTxInputs):
+                        if !defragTxInputs.isEmpty {
+                            logger.info(
+                                "Preparing \(defragTxInputs.count) defrag transactions",
+                                logFunction: false)
+                        }
+                        let tombstoneBlockIndex = ledgerBlockCount + 50
+                        defragTxInputs.mapAsync({ defragInputs, callback in
+                            self.transactionPreparer.prepareSelfAddressedTransaction(
+                                inputs: defragInputs.inputs,
+                                fee: defragInputs.fee,
+                                tombstoneBlockIndex: tombstoneBlockIndex,
+                                completion: callback)
+                        }, serialQueue: self.serialQueue, completion: completion)
+                    case .failure(let error):
+                        logger.info(
+                            "prepareDefragmentationStepTransactions failure: \(error)",
+                            logFunction: false)
+                        self.serialQueue.async {
+                            completion(.failure(.insufficientBalance()))
+                        }
+                    }
+                case .failure(let connectionError):
+                    logger.info("failure - error: \(connectionError)")
+                    completion(.failure(.connectionError(connectionError)))
+                }
+            }
+        }
+    }
+}
--- a/Sources/Account/Account.swift
+++ b/Sources/Account/Account.swift
@ -0,0 +1,220 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+final class Account {
+    let accountKey: AccountKey
+
+    let fogView = FogView()
+
+    var allTxOutTrackers: [TxOutTracker] = []
+
+    init(accountKey: AccountKeyWithFog) {
+        self.accountKey = accountKey.accountKey
+    }
+
+    var publicAddress: PublicAddress {
+        accountKey.publicAddress
+    }
+
+    var unscannedMissedBlocksRanges: [Range<UInt64>] { fogView.unscannedMissedBlocksRanges }
+
+    private var allTxOutsFoundBlockCount: UInt64 {
+        var allTxOutsFoundBlockCount = fogView.allRngTxOutsFoundBlockCount
+        for unscannedMissedBlocksRange in unscannedMissedBlocksRanges
+            where unscannedMissedBlocksRange.lowerBound < allTxOutsFoundBlockCount
+        {
+            allTxOutsFoundBlockCount = unscannedMissedBlocksRange.lowerBound
+        }
+        return allTxOutsFoundBlockCount
+    }
+
+    /// The number of blocks for which we have complete knowledge of this Account's wallet.
+    var knowableBlockCount: UInt64 {
+        var knowableBlockCount = allTxOutsFoundBlockCount
+        for txOut in allTxOutTrackers {
+            if case .unspent(let knownToBeUnspentBlockCount) = txOut.spentStatus {
+                knowableBlockCount = min(knowableBlockCount, knownToBeUnspentBlockCount)
+            }
+        }
+        return knowableBlockCount
+    }
+
+    var cachedBalance: Balance {
+        let blockCount = knowableBlockCount
+        let txOutValues = allTxOutTrackers
+            .filter { $0.receivedAndUnspent(asOfBlockCount: blockCount) }
+            .map { $0.knownTxOut.value }
+        return Balance(values: txOutValues, blockCount: blockCount)
+    }
+
+    var cachedAccountActivity: AccountActivity {
+        let blockCount = knowableBlockCount
+        let txOuts = allTxOutTrackers.compactMap { OwnedTxOut($0, atBlockCount: blockCount) }
+        return AccountActivity(txOuts: txOuts, blockCount: blockCount)
+    }
+
+    var ownedTxOuts: [KnownTxOut] {
+        ownedTxOutsAndBlockCount.txOuts
+    }
+
+    var ownedTxOutsAndBlockCount: (txOuts: [KnownTxOut], blockCount: UInt64) {
+        let knowableBlockCount = self.knowableBlockCount
+        let txOuts = allTxOutTrackers
+            .filter { $0.received(asOfBlockCount: knowableBlockCount) }
+            .map { $0.knownTxOut }
+        return (txOuts: txOuts, blockCount: knowableBlockCount)
+    }
+
+    var unspentTxOuts: [KnownTxOut] {
+        unspentTxOutsAndBlockCount.txOuts
+    }
+
+    var unspentTxOutsAndBlockCount: (txOuts: [KnownTxOut], blockCount: UInt64) {
+        let knowableBlockCount = self.knowableBlockCount
+        let txOuts = allTxOutTrackers
+            .filter { $0.receivedAndUnspent(asOfBlockCount: knowableBlockCount) }
+            .map { $0.knownTxOut }
+        return (txOuts: txOuts, blockCount: knowableBlockCount)
+    }
+
+    func addTxOuts(_ txOuts: [KnownTxOut]) {
+        allTxOutTrackers.append(contentsOf: txOuts.map { TxOutTracker($0) })
+    }
+
+    func addViewKeyScanResults(scannedBlockRanges: [Range<UInt64>], foundTxOuts: [KnownTxOut]) {
+        addTxOuts(foundTxOuts)
+        fogView.markBlocksAsScanned(blockRanges: scannedBlockRanges)
+    }
+
+    func cachedReceivedStatus(of receipt: Receipt)
+        -> Result<Receipt.ReceivedStatus, InvalidInputError>
+    {
+        ownedTxOut(for: receipt).map {
+            if let ownedTxOut = $0 {
+                return .received(block: ownedTxOut.block)
+            } else {
+                let knownToBeNotReceivedBlockCount = allTxOutsFoundBlockCount
+                guard receipt.txTombstoneBlockIndex > knownToBeNotReceivedBlockCount else {
+                    return .tombstoneExceeded
+                }
+                return .notReceived(knownToBeNotReceivedBlockCount: knownToBeNotReceivedBlockCount)
+            }
+        }
+    }
+
+    /// Retrieves the `KnownTxOut`'s corresponding to `receipt` and verifies `receipt` is valid.
+    private func ownedTxOut(for receipt: Receipt) -> Result<KnownTxOut?, InvalidInputError> {
+        logger.debug(
+            "Last received TxOut: TxOut pubkey: " +
+                "\(redacting: ownedTxOuts.last?.publicKey.hexEncodedString() ?? "None")",
+            logFunction: false)
+
+        // First check if we've received the TxOut (either from Fog View or from view key scanning).
+        // This has the benefit of providing a guarantee that the TxOut is owned by this account.
+        guard let ownedTxOut = ownedTxOut(for: receipt.txOutPublicKeyTyped) else {
+            return .success(nil)
+        }
+
+        // Make sure the Receipt data matches the TxOut found in the ledger. This verifies that the
+        // public key, commitment, and masked value match.
+        //
+        // Note: This doesn't verify the confirmation number or tombstone block (since neither are
+        // saved to the ledger).
+        guard receipt.matchesTxOut(ownedTxOut) else {
+            let errorMessage =
+                "Receipt data doesn't match the corresponding TxOut found in the ledger. " +
+                "Receipt: \(redacting: receipt.serializedData.base64EncodedString()) - " +
+                "Account TxOut: \(redacting: ownedTxOut)"
+            logger.error(errorMessage, sensitive: true, logFunction: false)
+            return .failure(InvalidInputError(errorMessage))
+        }
+
+        // Verify that the confirmation number validates for this account key. This provides a
+        // guarantee that the sender of the Receipt was the creator of the TxOut that we received.
+        guard receipt.validateConfirmationNumber(accountKey: accountKey) else {
+            let errorMessage = "Receipt confirmation number is invalid for this account. " +
+                "Receipt: \(redacting: receipt.serializedData.base64EncodedString())"
+            logger.error(errorMessage, sensitive: true, logFunction: false)
+            return .failure(InvalidInputError(errorMessage))
+        }
+
+        return .success(ownedTxOut)
+    }
+
+    private func ownedTxOut(for txOutPublicKey: RistrettoPublic) -> KnownTxOut? {
+        ownedTxOuts.first(where: { $0.publicKey == txOutPublicKey })
+    }
+}
+
+extension Account {
+    /// - Returns: `.failure` if `accountKey` doesn't use Fog.
+    static func make(accountKey: AccountKey) -> Result<Account, InvalidInputError> {
+        guard let accountKey = AccountKeyWithFog(accountKey: accountKey) else {
+            let errorMessage = "Accounts without fog URLs are not currently supported."
+            logger.error(errorMessage, logFunction: false)
+            return .failure(InvalidInputError(errorMessage))
+        }
+        return .success(Account(accountKey: accountKey))
+    }
+}
+
+extension Account: CustomRedactingStringConvertible {
+    var redactingDescription: String {
+        publicAddress.redactingDescription
+    }
+}
+
+final class TxOutTracker {
+    let knownTxOut: KnownTxOut
+
+    var keyImageTracker: KeyImageSpentTracker
+
+    init(_ knownTxOut: KnownTxOut) {
+        self.knownTxOut = knownTxOut
+        self.keyImageTracker = KeyImageSpentTracker(knownTxOut.keyImage)
+    }
+
+    var spentStatus: KeyImage.SpentStatus {
+        keyImageTracker.spentStatus
+    }
+
+    var isSpent: Bool {
+        keyImageTracker.isSpent
+    }
+
+    func receivedAndUnspent(asOfBlockCount blockCount: UInt64) -> Bool {
+        received(asOfBlockCount: blockCount) && !spent(asOfBlockCount: blockCount)
+    }
+
+    func received(asOfBlockCount blockCount: UInt64) -> Bool {
+        knownTxOut.block.index < blockCount
+    }
+
+    func spent(asOfBlockCount blockCount: UInt64) -> Bool {
+        if case .spent = keyImageTracker.spentStatus.status(atBlockCount: blockCount) {
+            return true
+        }
+        return false
+    }
+}
+
+extension OwnedTxOut {
+    fileprivate init?(_ txOutTracker: TxOutTracker, atBlockCount blockCount: UInt64) {
+        guard txOutTracker.knownTxOut.block.index < blockCount else {
+            return nil
+        }
+        let receivedBlock = txOutTracker.knownTxOut.block
+
+        let spentBlock: BlockMetadata?
+        if case .spent(let block) = txOutTracker.spentStatus, block.index < blockCount {
+            spentBlock = block
+        } else {
+            spentBlock = nil
+        }
+
+        self.init(txOutTracker.knownTxOut, receivedBlock: receivedBlock, spentBlock: spentBlock)
+    }
+}
--- a/Sources/Account/AccountActivity.swift
+++ b/Sources/Account/AccountActivity.swift
@ -0,0 +1,18 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+/// Provides a snapshot of account activity at a particular point in the ledger, as indicated by
+/// `blockCount`.
+public struct AccountActivity {
+    public let txOuts: Set<OwnedTxOut>
+
+    public let blockCount: UInt64
+
+    init(txOuts: [OwnedTxOut], blockCount: UInt64) {
+        self.txOuts = Set(txOuts)
+        self.blockCount = blockCount
+    }
+}
--- a/Sources/Account/AccountKey.swift
+++ b/Sources/Account/AccountKey.swift
@ -0,0 +1,189 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+public struct AccountKey {
+    static func make(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        fogReportUrl: String,
+        fogReportId: String,
+        fogAuthoritySpki: Data,
+        subaddressIndex: UInt64 = McConstants.DEFAULT_SUBADDRESS_INDEX
+    ) -> Result<AccountKey, InvalidInputError> {
+        FogInfo.make(
+            reportUrl: fogReportUrl,
+            reportId: fogReportId,
+            authoritySpki: fogAuthoritySpki
+        ).map { fogInfo in
+            AccountKey(
+                viewPrivateKey: viewPrivateKey,
+                spendPrivateKey: spendPrivateKey,
+                fogInfo: fogInfo,
+                subaddressIndex: subaddressIndex)
+        }
+    }
+
+    let viewPrivateKey: RistrettoPrivate
+    let spendPrivateKey: RistrettoPrivate
+    let fogInfo: FogInfo?
+    let subaddressIndex: UInt64
+
+    public let publicAddress: PublicAddress
+
+    init(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        fogInfo: FogInfo? = nil,
+        subaddressIndex: UInt64 = McConstants.DEFAULT_SUBADDRESS_INDEX
+    ) {
+        self.viewPrivateKey = viewPrivateKey
+        self.spendPrivateKey = spendPrivateKey
+        self.fogInfo = fogInfo
+        self.subaddressIndex = subaddressIndex
+        self.publicAddress = PublicAddress(
+            viewPrivateKey: viewPrivateKey,
+            spendPrivateKey: spendPrivateKey,
+            accountKeyFogInfo: fogInfo,
+            subaddressIndex: subaddressIndex)
+    }
+
+    /// - Returns: `nil` when the input is not deserializable.
+    public init?(serializedData: Data) {
+        guard let proto = try? External_AccountKey(serializedData: serializedData) else {
+            logger.error("External_AccountKey deserialization failed.", logFunction: false)
+            return nil
+        }
+        self.init(proto)
+    }
+
+    public var serializedData: Data {
+        let proto = External_AccountKey(self)
+        return proto.serializedDataInfallible
+    }
+
+    var fogReportUrlString: String? { fogInfo?.reportUrlString }
+    var fogReportUrl: FogUrl? { fogInfo?.reportUrl }
+    var fogReportId: String? { fogInfo?.reportId }
+    var fogAuthoritySpki: Data? { fogInfo?.authoritySpki }
+
+    var subaddressViewPrivateKey: RistrettoPrivate {
+        AccountKeyUtils.subaddressPrivateKeys(
+            viewPrivateKey: viewPrivateKey,
+            spendPrivateKey: spendPrivateKey,
+            subaddressIndex: subaddressIndex
+        ).subaddressViewPrivateKey
+    }
+
+    var subaddressSpendPrivateKey: RistrettoPrivate {
+        AccountKeyUtils.subaddressPrivateKeys(
+            viewPrivateKey: viewPrivateKey,
+            spendPrivateKey: spendPrivateKey,
+            subaddressIndex: subaddressIndex
+        ).subaddressSpendPrivateKey
+    }
+}
+
+extension AccountKey: Equatable {}
+extension AccountKey: Hashable {}
+
+extension AccountKey {
+    init?(
+        _ proto: External_AccountKey,
+        subaddressIndex: UInt64 = McConstants.DEFAULT_SUBADDRESS_INDEX
+    ) {
+        guard let viewPrivateKey = RistrettoPrivate(proto.viewPrivateKey.data),
+              let spendPrivateKey = RistrettoPrivate(proto.spendPrivateKey.data)
+        else {
+            return nil
+        }
+
+        let maybeFogInfo: FogInfo?
+        if !proto.fogReportURL.isEmpty {
+            guard case .success(let fogInfo) = FogInfo.make(
+                reportUrl: proto.fogReportURL,
+                reportId: proto.fogReportID,
+                authoritySpki: proto.fogAuthoritySpki)
+            else {
+                return nil
+            }
+            maybeFogInfo = fogInfo
+        } else {
+            maybeFogInfo = nil
+        }
+
+        self.init(
+            viewPrivateKey: viewPrivateKey,
+            spendPrivateKey: spendPrivateKey,
+            fogInfo: maybeFogInfo,
+            subaddressIndex: subaddressIndex)
+    }
+}
+
+extension External_AccountKey {
+    init(_ accountKey: AccountKey) {
+        self.init()
+        self.viewPrivateKey = External_RistrettoPrivate(accountKey.viewPrivateKey)
+        self.spendPrivateKey = External_RistrettoPrivate(accountKey.spendPrivateKey)
+        if let fogInfo = accountKey.fogInfo {
+            self.fogReportURL = fogInfo.reportUrlString
+            self.fogReportID = fogInfo.reportId
+            self.fogAuthoritySpki = fogInfo.authoritySpki
+        }
+    }
+}
+
+extension AccountKey {
+    struct FogInfo {
+        fileprivate static func make(reportUrl: String, reportId: String, authoritySpki: Data)
+            -> Result<FogInfo, InvalidInputError>
+        {
+            FogUrl.make(string: reportUrl).map { reportUrlTyped in
+                FogInfo(
+                    reportUrlString: reportUrl,
+                    reportUrl: reportUrlTyped,
+                    reportId: reportId,
+                    authoritySpki: authoritySpki)
+            }
+        }
+
+        let reportUrlString: String
+        let reportUrl: FogUrl
+        let reportId: String
+        let authoritySpki: Data
+
+        private init(
+            reportUrlString: String,
+            reportUrl: FogUrl,
+            reportId: String,
+            authoritySpki: Data
+        ) {
+            self.reportUrlString = reportUrlString
+            self.reportUrl = reportUrl
+            self.reportId = reportId
+            self.authoritySpki = authoritySpki
+        }
+    }
+}
+
+extension AccountKey.FogInfo: Equatable {}
+extension AccountKey.FogInfo: Hashable {}
+
+struct AccountKeyWithFog {
+    let accountKey: AccountKey
+    let fogInfo: AccountKey.FogInfo
+
+    init?(accountKey: AccountKey) {
+        guard let fogInfo = accountKey.fogInfo else {
+            return nil
+        }
+
+        self.accountKey = accountKey
+        self.fogInfo = fogInfo
+    }
+}
--- a/Sources/Account/AccountKeyUtils.swift
+++ b/Sources/Account/AccountKeyUtils.swift
@ -0,0 +1,232 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable function_parameter_count
+
+import Foundation
+import LibMobileCoin
+
+enum AccountKeyUtils {
+    static func subaddressPrivateKeys(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        subaddressIndex: UInt64
+    ) -> (subaddressViewPrivateKey: RistrettoPrivate, subaddressSpendPrivateKey: RistrettoPrivate) {
+        var subaddressViewPrivateKeyOut = Data32()
+        var subaddressSpendPrivateKeyOut = Data32()
+        viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+            spendPrivateKey.asMcBuffer { spendKeyBufferPtr in
+                subaddressViewPrivateKeyOut.asMcMutableBuffer { viewPrivateKeyOutPtr in
+                    subaddressSpendPrivateKeyOut.asMcMutableBuffer { spendPrivateKeyOutPtr in
+                        withMcInfallible {
+                            mc_account_key_get_subaddress_private_keys(
+                                viewKeyBufferPtr,
+                                spendKeyBufferPtr,
+                                subaddressIndex,
+                                viewPrivateKeyOutPtr,
+                                spendPrivateKeyOutPtr)
+                        }
+                    }
+                }
+            }
+        }
+        // Safety: It's safe to skip validation because mc_account_key_get_subaddress_private_keys
+        // should always return valid RistrettoPrivate values on success.
+        return (RistrettoPrivate(skippingValidation: subaddressViewPrivateKeyOut),
+                RistrettoPrivate(skippingValidation: subaddressSpendPrivateKeyOut))
+    }
+
+    static func publicAddressPublicKeys(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        subaddressIndex: UInt64
+    ) -> (viewPublicKey: RistrettoPublic, spendPublicKey: RistrettoPublic) {
+        var viewPublicKeyOut = Data32()
+        var spendPublicKeyOut = Data32()
+        viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+            spendPrivateKey.asMcBuffer { spendKeyBufferPtr in
+                viewPublicKeyOut.asMcMutableBuffer { viewPublicKeyOutPtr in
+                    spendPublicKeyOut.asMcMutableBuffer { spendPublicKeyOutPtr in
+                        withMcInfallible {
+                            mc_account_key_get_public_address_public_keys(
+                                viewKeyBufferPtr,
+                                spendKeyBufferPtr,
+                                subaddressIndex,
+                                viewPublicKeyOutPtr,
+                                spendPublicKeyOutPtr)
+                        }
+                    }
+                }
+            }
+        }
+        // Safety: It's safe to skip validation because
+        // mc_account_key_get_public_address_public_keys should always return valid RistrettoPublic
+        // values on success.
+        return (RistrettoPublic(skippingValidation: viewPublicKeyOut),
+                RistrettoPublic(skippingValidation: spendPublicKeyOut))
+    }
+
+    static func fogAuthoritySig(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        reportUrl: String,
+        reportId: String,
+        authoritySpki: Data,
+        subaddressIndex: UInt64
+    ) -> Data {
+        McAccountKey.withUnsafePointer(
+            viewPrivateKey: viewPrivateKey,
+            spendPrivateKey: spendPrivateKey,
+            reportUrl: reportUrl,
+            reportId: reportId,
+            authoritySpki: authoritySpki
+        ) { accountKeyPtr in
+            Data(withFixedLengthMcMutableBufferInfallible: McConstants.SCHNORRKEL_SIGNATURE_LEN)
+            { bufferPtr in
+                mc_account_key_get_public_address_fog_authority_sig(
+                    accountKeyPtr,
+                    subaddressIndex,
+                    bufferPtr)
+            }
+        }
+    }
+}
+
+extension McAccountKey {
+    fileprivate static func withUnsafePointer<T>(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        reportUrl: String,
+        reportId: String,
+        authoritySpki: Data,
+        body: (UnsafePointer<McAccountKey>) throws -> T
+    ) rethrows -> T {
+        try McAccountKeyFogInfo.withUnsafePointer(
+            reportUrl: reportUrl,
+            reportId: reportId,
+            authoritySpki: authoritySpki
+        ) { fogInfoPtr in
+            try viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+                try spendPrivateKey.asMcBuffer { spendKeyBufferPtr in
+                    var publicAddress = McAccountKey(
+                        view_private_key: viewKeyBufferPtr,
+                        spend_private_key: spendKeyBufferPtr,
+                        fog_info: fogInfoPtr)
+                    return try body(&publicAddress)
+                }
+            }
+        }
+    }
+
+    fileprivate static func withUnsafePointer<T>(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        body: (UnsafePointer<McAccountKey>) throws -> T
+    ) rethrows -> T {
+        try viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+            try spendPrivateKey.asMcBuffer { spendKeyBufferPtr in
+                var publicAddress = McAccountKey(
+                    view_private_key: viewKeyBufferPtr,
+                    spend_private_key: spendKeyBufferPtr,
+                    fog_info: nil)
+                return try body(&publicAddress)
+            }
+        }
+    }
+}
+
+extension AccountKey: CStructWrapper {
+    typealias CStruct = McAccountKey
+
+    func withUnsafeCStructPointer<R>(
+        _ body: (UnsafePointer<McAccountKey>) throws -> R
+    ) rethrows -> R {
+        try fogInfo.withUnsafeCStructPointer { fogInfoPtr in
+            try viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+                try spendPrivateKey.asMcBuffer { spendKeyBufferPtr in
+                    var publicAddress = McAccountKey(
+                        view_private_key: viewKeyBufferPtr,
+                        spend_private_key: spendKeyBufferPtr,
+                        fog_info: fogInfoPtr)
+                    return try body(&publicAddress)
+                }
+            }
+        }
+    }
+}
+
+extension McAccountKeyFogInfo {
+    fileprivate static func withUnsafePointer<T>(
+        reportUrl: String,
+        reportId: String,
+        authoritySpki: Data,
+        body: (UnsafePointer<McAccountKeyFogInfo>) throws -> T
+    ) rethrows -> T {
+        try reportUrl.withCString { reportUrlPtr in
+            try reportId.withCString { reportIdPtr in
+                try authoritySpki.asMcBuffer { authoritySpkiPtr in
+                    var mcFogInfo = McAccountKeyFogInfo(
+                        report_url: reportUrlPtr,
+                        report_id: reportIdPtr,
+                        authority_fingerprint: authoritySpkiPtr)
+                    return try body(&mcFogInfo)
+                }
+            }
+        }
+    }
+}
+
+extension AccountKey.FogInfo: CStructWrapper {
+    typealias CStruct = McAccountKeyFogInfo
+
+    func withUnsafeCStructPointer<R>(
+        _ body: (UnsafePointer<McAccountKeyFogInfo>) throws -> R
+    ) rethrows -> R {
+        try McAccountKeyFogInfo.withUnsafePointer(
+            reportUrl: reportUrlString,
+            reportId: reportId,
+            authoritySpki: authoritySpki,
+            body: body)
+    }
+}
+
+extension PublicAddress: CStructWrapper {
+    typealias CStruct = McPublicAddress
+
+    func withUnsafeCStructPointer<R>(
+        _ body: (UnsafePointer<McPublicAddress>) throws -> R
+    ) rethrows -> R {
+        try viewPublicKey.asMcBuffer { viewKeyBufferPtr in
+            try spendPublicKey.asMcBuffer { spendKeyBufferPtr in
+                try fogInfo.withUnsafeCStructPointer { fogInfoPtr in
+                    var publicAddress = McPublicAddress(
+                        view_public_key: viewKeyBufferPtr,
+                        spend_public_key: spendKeyBufferPtr,
+                        fog_info: fogInfoPtr)
+                    return try body(&publicAddress)
+                }
+            }
+        }
+    }
+}
+
+extension PublicAddress.FogInfo: CStructWrapper {
+    typealias CStruct = McPublicAddressFogInfo
+
+    func withUnsafeCStructPointer<R>(
+        _ body: (UnsafePointer<McPublicAddressFogInfo>) throws -> R
+    ) rethrows -> R {
+        try reportUrlString.withCString { reportUrlPtr in
+            try reportId.withCString { reportIdPtr in
+                try authoritySig.asMcBuffer { authoritySigPtr in
+                    var mcFogInfo = McPublicAddressFogInfo(
+                        report_url: reportUrlPtr,
+                        report_id: reportIdPtr,
+                        authority_sig: authoritySigPtr)
+                    return try body(&mcFogInfo)
+                }
+            }
+        }
+    }
+}
--- a/Sources/Account/Balance.swift
+++ b/Sources/Account/Balance.swift
@ -0,0 +1,108 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+public struct Balance {
+    public let amountPicoMobLow: UInt64
+    public let amountPicoMobHigh: UInt8
+    let blockCount: UInt64
+
+    init(values: [UInt64], blockCount: UInt64) {
+        var amountLow: UInt64 = 0
+        var amountHigh: UInt8 = 0
+        for value in values {
+            let (partialValue, overflow) = amountLow.addingReportingOverflow(value)
+            amountLow = partialValue
+            if overflow {
+                amountHigh += 1
+            }
+        }
+        self.init(amountLow: amountLow, amountHigh: amountHigh, blockCount: blockCount)
+    }
+
+    init(amountLow: UInt64, amountHigh: UInt8, blockCount: UInt64) {
+        self.amountPicoMobLow = amountLow
+        self.amountPicoMobHigh = amountHigh
+        self.blockCount = blockCount
+    }
+
+    /// - Returns: `nil` when the amount is too large to fit in a `UInt64`.
+    public func amountPicoMob() -> UInt64? {
+        guard amountPicoMobHigh == 0 else {
+            return nil
+        }
+        return amountPicoMobLow
+    }
+
+    /// Convenience accessor for balance value. `mobInt` is the integer part of the value when
+    /// represented in MOB. `picoFrac` is the fractional part of the value when represented in MOB.
+    /// However, rather than reprenting the fractional part as a decimal fraction, it is represented
+    /// in picoMOB, thus allowing both parts to be integer values.
+    ///
+    /// The purpose of this representation is to facilitate presenting the balance to the user in
+    /// MOB form.
+    ///
+    /// To illustrate, given an amount in the form of XXXXXXXXX.YYYYYYYYYYYY MOB,
+    /// - `mobInt`: XXXXXXXXX (denominated in MOB)
+    /// - `picoFrac`: YYYYYYYYYYYY (denominated in picoMOB)
+    ///
+    /// It is necessary to break apart the values into 2 parts because the total max possible
+    /// balance is too large to fit in a single `UInt64`, when denominated in picoMOB, assuming 250
+    /// million MOB in circulation and assuming a base unit of 1 picoMOB as the smallest indivisible
+    /// unit of MOB.
+    public var amountMobParts: (mobInt: UInt32, picoFrac: UInt64) {
+        // amount (picoMOB) = amountLow + amountHigh * 2^64
+        //
+        // amountLowMobDec = amountLow / 10^12
+        // amountHighMobDec = amountHigh * 2^64 / 10^12
+        //
+        // amountMobDec = amountLowMobDec + amountHighMobDec
+        //
+        // amountLowMobInt = floor(amountLow / 10^12)
+        // amountLowPicoFrac = amountLow % 10^12
+
+        // amountHighMobInt = floor((amountHigh * 2^64) / 10^12)
+        //                  = floor((amountHigh << 52) / 5^12)
+        // amountHighPicoFrac = (amountHigh * 2^64) % 10^12
+        //                   = ((amountHigh << 52) % 5^12) << 12
+        //
+        // amountPicoFracCarry = floor((amountLowPicoFrac + amountHighPicoFrac) / 10^12)
+        //
+        // amountMobInt = amountLowMobInt + amountHighMobInt + amountPicoFracCarry
+        // amountPicoFrac = (amountLowPicoFrac + amountHighPicoFrac) % 10^12
+
+        let (amountLowMobInt, amountLowPicoFrac) = { () -> (UInt32, UInt64) in
+            // 10^12 = 1_000_000_000_000
+            let mobParts = amountPicoMobLow.quotientAndRemainder(dividingBy: 1_000_000_000_000)
+            return (UInt32(mobParts.quotient), mobParts.remainder)
+        }()
+
+        let (amountHighMobInt, amountHighPicoFrac) = { () -> (UInt32, UInt64) in
+            // Intermediary = base of 5^-12 MOB
+            let amountHighIntermediary = UInt64(amountPicoMobHigh) << 52
+            // 5^12 = 244_140_625
+            let mobParts = amountHighIntermediary.quotientAndRemainder(dividingBy: 244_140_625)
+            return (UInt32(mobParts.quotient), mobParts.remainder << 12)
+        }()
+
+        let amountPicoFracParts = (amountLowPicoFrac + amountHighPicoFrac).quotientAndRemainder(
+            dividingBy: 1_000_000_000_000)
+
+        let amountMobInt = amountLowMobInt + amountHighMobInt + UInt32(amountPicoFracParts.quotient)
+        let amountPicoFrac = amountPicoFracParts.remainder
+
+        return (amountMobInt, amountPicoFrac)
+    }
+}
+
+extension Balance: Equatable {}
+extension Balance: Hashable {}
+
+extension Balance: CustomStringConvertible {
+    public var description: String {
+        let amountMob = amountMobParts
+        return String(format: "%u.%012llu MOB", amountMob.mobInt, amountMob.picoFrac)
+    }
+}
--- a/Sources/Account/OwnedTxOut.swift
+++ b/Sources/Account/OwnedTxOut.swift
@ -0,0 +1,36 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+public struct OwnedTxOut {
+    let publicKeyTyped: RistrettoPublic
+    /// - Returns: `TxOut` public key
+    public var publicKey: Data { publicKeyTyped.data }
+
+    public let value: UInt64
+
+    let keyImageTyped: KeyImage
+    /// - Returns: `TxOut` key  image
+    public var keyImage: Data { keyImageTyped.data }
+
+    public let receivedBlock: BlockMetadata
+
+    public let spentBlock: BlockMetadata?
+
+    init(
+        _ knownTxOut: KnownTxOut,
+        receivedBlock: BlockMetadata,
+        spentBlock: BlockMetadata?
+    ) {
+        self.publicKeyTyped = knownTxOut.publicKey
+        self.value = knownTxOut.value
+        self.keyImageTyped = knownTxOut.keyImage
+        self.receivedBlock = receivedBlock
+        self.spentBlock = spentBlock
+    }
+}
+
+extension OwnedTxOut: Equatable {}
+extension OwnedTxOut: Hashable {}
--- a/Sources/Account/PublicAddress.swift
+++ b/Sources/Account/PublicAddress.swift
@ -0,0 +1,197 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+public struct PublicAddress {
+    static func make(
+        viewPublicKey: RistrettoPublic,
+        spendPublicKey: RistrettoPublic,
+        fogReportUrl: String,
+        fogReportId: String,
+        fogAuthoritySig: Data
+    ) -> Result<PublicAddress, InvalidInputError> {
+        FogInfo.make(
+            reportUrl: fogReportUrl,
+            reportId: fogReportId,
+            authoritySig: fogAuthoritySig)
+            .map { fogInfo in
+                PublicAddress(
+                    viewPublicKey: viewPublicKey,
+                    spendPublicKey: spendPublicKey,
+                    fogInfo: fogInfo)
+            }
+    }
+
+    let viewPublicKeyTyped: RistrettoPublic
+    let spendPublicKeyTyped: RistrettoPublic
+    let fogInfo: FogInfo?
+
+    init(viewPublicKey: RistrettoPublic, spendPublicKey: RistrettoPublic, fogInfo: FogInfo? = nil) {
+        self.viewPublicKeyTyped = viewPublicKey
+        self.spendPublicKeyTyped = spendPublicKey
+        self.fogInfo = fogInfo
+    }
+
+    /// - Returns: `nil` when the input is not deserializable.
+    public init?(serializedData: Data) {
+        guard let proto = try? External_PublicAddress(serializedData: serializedData) else {
+            logger.warning("External_PublicAddress deserialization failed. serializedData: " +
+                "\(redacting: serializedData.base64EncodedString())")
+            return nil
+        }
+        self.init(proto)
+    }
+
+    public var serializedData: Data {
+        let proto = External_PublicAddress(self)
+        return proto.serializedDataInfallible
+    }
+
+    /// Subaddress view public key, `C`, in bytes.
+    public var viewPublicKey: Data { viewPublicKeyTyped.data }
+
+    /// Subaddress spend public key, `D`, in bytes.
+    public var spendPublicKey: Data { spendPublicKeyTyped.data }
+
+    public var fogReportUrlString: String? { fogInfo?.reportUrlString }
+
+    var fogReportUrl: FogUrl? { fogInfo?.reportUrl }
+    var fogReportId: String? { fogInfo?.reportId }
+    var fogAuthoritySig: Data? { fogInfo?.authoritySig }
+}
+
+extension PublicAddress: Equatable {}
+extension PublicAddress: Hashable {}
+
+extension PublicAddress: CustomRedactingStringConvertible {
+    var redactingDescription: String {
+        "PublicAddress(\(Base58Coder.encode(self)))"
+    }
+}
+
+extension PublicAddress {
+    init(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        accountKeyFogInfo: AccountKey.FogInfo? = nil,
+        subaddressIndex: UInt64 = McConstants.DEFAULT_SUBADDRESS_INDEX
+    ) {
+        let (viewPublicKey, spendPublicKey) = AccountKeyUtils.publicAddressPublicKeys(
+            viewPrivateKey: viewPrivateKey,
+            spendPrivateKey: spendPrivateKey,
+            subaddressIndex: subaddressIndex)
+
+        let fogInfo: FogInfo?
+        if let accountKeyFogInfo = accountKeyFogInfo {
+            fogInfo = FogInfo(
+                viewPrivateKey: viewPrivateKey,
+                spendPrivateKey: spendPrivateKey,
+                accountKeyFogInfo: accountKeyFogInfo,
+                subaddressIndex: subaddressIndex)
+        } else {
+            fogInfo = nil
+        }
+
+        self.init(viewPublicKey: viewPublicKey, spendPublicKey: spendPublicKey, fogInfo: fogInfo)
+    }
+}
+
+extension PublicAddress {
+    init?(_ publicAddress: External_PublicAddress) {
+        guard let viewPublicKey = RistrettoPublic(publicAddress.viewPublicKey),
+              let spendPublicKey = RistrettoPublic(publicAddress.spendPublicKey)
+        else {
+            return nil
+        }
+
+        let fogInfo: FogInfo?
+        if !publicAddress.fogReportURL.isEmpty {
+            guard case .success(let maybeFogInfo) = FogInfo.make(
+                reportUrl: publicAddress.fogReportURL,
+                reportId: publicAddress.fogReportID,
+                authoritySig: publicAddress.fogAuthoritySig)
+            else {
+                return nil
+            }
+            fogInfo = maybeFogInfo
+        } else {
+            fogInfo = nil
+        }
+
+        self.init(viewPublicKey: viewPublicKey, spendPublicKey: spendPublicKey, fogInfo: fogInfo)
+    }
+}
+
+extension External_PublicAddress {
+    init(_ publicAddress: PublicAddress) {
+        self.init()
+        self.viewPublicKey = External_CompressedRistretto(publicAddress.viewPublicKey)
+        self.spendPublicKey = External_CompressedRistretto(publicAddress.spendPublicKey)
+        if let fogInfo = publicAddress.fogInfo {
+            self.fogReportURL = fogInfo.reportUrlString
+            self.fogReportID = fogInfo.reportId
+            self.fogAuthoritySig = fogInfo.authoritySig
+        }
+    }
+}
+
+extension PublicAddress {
+    struct FogInfo {
+        fileprivate static func make(reportUrl: String, reportId: String, authoritySig: Data)
+            -> Result<FogInfo, InvalidInputError>
+        {
+            FogUrl.make(string: reportUrl).map { reportUrlTyped in
+                FogInfo(
+                    reportUrlString: reportUrl,
+                    reportUrl: reportUrlTyped,
+                    reportId: reportId,
+                    authoritySig: authoritySig)
+            }
+        }
+
+        let reportUrlString: String
+        let reportUrl: FogUrl
+        let reportId: String
+        let authoritySig: Data
+
+        private init(
+            reportUrlString: String,
+            reportUrl: FogUrl,
+            reportId: String,
+            authoritySig: Data
+        ) {
+            self.reportUrlString = reportUrlString
+            self.reportUrl = reportUrl
+            self.reportId = reportId
+            self.authoritySig = authoritySig
+        }
+    }
+}
+
+extension PublicAddress.FogInfo: Equatable {}
+extension PublicAddress.FogInfo: Hashable {}
+
+extension PublicAddress.FogInfo {
+    fileprivate init(
+        viewPrivateKey: RistrettoPrivate,
+        spendPrivateKey: RistrettoPrivate,
+        accountKeyFogInfo: AccountKey.FogInfo,
+        subaddressIndex: UInt64 = McConstants.DEFAULT_SUBADDRESS_INDEX
+    ) {
+        let authoritySig = AccountKeyUtils.fogAuthoritySig(
+            viewPrivateKey: viewPrivateKey,
+            spendPrivateKey: spendPrivateKey,
+            reportUrl: accountKeyFogInfo.reportUrlString,
+            reportId: accountKeyFogInfo.reportId,
+            authoritySpki: accountKeyFogInfo.authoritySpki,
+            subaddressIndex: subaddressIndex)
+        self.init(
+            reportUrlString: accountKeyFogInfo.reportUrlString,
+            reportUrl: accountKeyFogInfo.reportUrl,
+            reportId: accountKeyFogInfo.reportId,
+            authoritySig: authoritySig)
+    }
+}
--- a/Sources/Common/Errors.swift
+++ b/Sources/Common/Errors.swift
@ -0,0 +1,208 @@
+// swiftlint:disable:this file_name
+
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+public struct InvalidInputError: Error {
+    let reason: String
+
+    init(_ reason: String) {
+        self.reason = reason
+    }
+}
+
+extension InvalidInputError: CustomStringConvertible {
+    public var description: String {
+        "Invalid input: \(reason)"
+    }
+}
+
+public enum ConnectionError: Error {
+    case connectionFailure(String)
+    case authorizationFailure(String)
+    case invalidServerResponse(String)
+    case attestationVerificationFailed(String)
+    case outdatedClient(String)
+    case serverRateLimited(String)
+}
+
+extension ConnectionError: CustomStringConvertible {
+    public var description: String {
+        "Connection error: " + {
+            switch self {
+            case .connectionFailure(let reason):
+                return "Connection failure: \(reason)"
+            case .authorizationFailure(let reason):
+                return "Authorization failure: \(reason)"
+            case .invalidServerResponse(let reason):
+                return "Invalid server response: \(reason)"
+            case .attestationVerificationFailed(let reason):
+                return "Attestation verification failed: \(reason)"
+            case .outdatedClient(let reason):
+                return "Outdated client: \(reason)"
+            case .serverRateLimited(let reason):
+                return "Server rate limited: \(reason)"
+            }
+        }()
+    }
+}
+
+public enum BalanceTransferEstimationFetcherError: Error {
+    case feeExceedsBalance(String = String())
+    case balanceOverflow(String = String())
+    case connectionError(ConnectionError)
+}
+
+extension BalanceTransferEstimationFetcherError: CustomStringConvertible {
+    public var description: String {
+        "Balance transfer estimation error: " + {
+            switch self {
+            case .feeExceedsBalance(let reason):
+                return "Fee exceeds balance\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .balanceOverflow(let reason):
+                return "Balance overflow\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .connectionError(let innerError):
+                return "\(innerError)"
+            }
+        }()
+    }
+}
+
+public enum TransactionEstimationFetcherError: Error {
+    case invalidInput(String)
+    case insufficientBalance(String = String())
+    case connectionError(ConnectionError)
+}
+
+extension TransactionEstimationFetcherError: CustomStringConvertible {
+    public var description: String {
+        "Transaction estimation error: " + {
+            switch self {
+            case .invalidInput(let reason):
+                return "Invalid input: \(reason)"
+            case .insufficientBalance(let reason):
+                return "Insufficient balance\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .connectionError(let innerError):
+                return "\(innerError)"
+            }
+        }()
+    }
+}
+
+public enum TransactionPreparationError: Error {
+    case invalidInput(String)
+    case insufficientBalance(String = String())
+    case defragmentationRequired(String = String())
+    case connectionError(ConnectionError)
+}
+
+extension TransactionPreparationError: CustomStringConvertible {
+    public var description: String {
+        "Transaction preparation error: " + {
+            switch self {
+            case .invalidInput(let reason):
+                return "Invalid input: \(reason)"
+            case .insufficientBalance(let reason):
+                return "Insufficient balance\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .defragmentationRequired(let reason):
+                return "Defragmentation required\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .connectionError(let innerError):
+                return "\(innerError)"
+            }
+        }()
+    }
+}
+
+public enum DefragTransactionPreparationError: Error {
+    case invalidInput(String)
+    case insufficientBalance(String = String())
+    case connectionError(ConnectionError)
+}
+
+extension DefragTransactionPreparationError: CustomStringConvertible {
+    public var description: String {
+        "Defragmentation transaction preparation error: " + {
+            switch self {
+            case .invalidInput(let reason):
+                return "Invalid input: \(reason)"
+            case .insufficientBalance(let reason):
+                return "Insufficient balance\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .connectionError(let innerError):
+                return "\(innerError)"
+            }
+        }()
+    }
+}
+
+public enum TransactionSubmissionError: Error {
+    case connectionError(ConnectionError)
+    case invalidTransaction(String = String())
+    case feeError(String = String())
+    case tombstoneBlockTooFar(String = String())
+    case missingMemo(String = String())
+    case inputsAlreadySpent(String = String())
+}
+
+extension TransactionSubmissionError: CustomStringConvertible {
+    public var description: String {
+        "Transaction submission error: " + {
+            switch self {
+            case .connectionError(let connectionError):
+                return "\(connectionError)"
+            case .missingMemo(let reason):
+                return "Missing memo error\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .feeError(let reason):
+                return "Fee error\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .invalidTransaction(let reason):
+                return "Invalid transaction\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .tombstoneBlockTooFar(let reason):
+                return "Tombstone block too far\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .inputsAlreadySpent(let reason):
+                return "Inputs already spent\(!reason.isEmpty ? ": \(reason)" : "")"
+            }
+        }()
+    }
+}
+
+@available(*, deprecated)
+public enum BalanceTransferEstimationError: Error {
+    case feeExceedsBalance(String = String())
+    case balanceOverflow(String = String())
+}
+
+@available(*, deprecated)
+extension BalanceTransferEstimationError: CustomStringConvertible {
+    public var description: String {
+        "Balance transfer estimation error: " + {
+            switch self {
+            case .feeExceedsBalance(let reason):
+                return "Fee exceeds balance\(!reason.isEmpty ? ": \(reason)" : "")"
+            case .balanceOverflow(let reason):
+                return "Balance overflow\(!reason.isEmpty ? ": \(reason)" : "")"
+            }
+        }()
+    }
+}
+
+@available(*, deprecated)
+public enum TransactionEstimationError: Error {
+    case invalidInput(String)
+    case insufficientBalance(String = String())
+}
+
+@available(*, deprecated)
+extension TransactionEstimationError: CustomStringConvertible {
+    public var description: String {
+        "Transaction estimation error: " + {
+            switch self {
+            case .invalidInput(let reason):
+                return "Invalid input: \(reason)"
+            case .insufficientBalance(let reason):
+                return "Insufficient balance\(!reason.isEmpty ? ": \(reason)" : "")"
+            }
+        }()
+    }
+}
--- a/Sources/Crypto/CryptoUtils.swift
+++ b/Sources/Crypto/CryptoUtils.swift
@ -0,0 +1,28 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+enum CryptoUtils {
+    static func ristrettoPrivateValidate(_ bytes: Data) -> Bool {
+        bytes.asMcBuffer { bytesPtr in
+            var valid = false
+            withMcInfallible {
+                mc_ristretto_private_validate(bytesPtr, &valid)
+            }
+            return valid
+        }
+    }
+
+    static func ristrettoPublicValidate(_ bytes: Data) -> Bool {
+        bytes.asMcBuffer { bytesPtr in
+            var valid = false
+            withMcInfallible {
+                mc_ristretto_public_validate(bytesPtr, &valid)
+            }
+            return valid
+        }
+    }
+}
--- a/Sources/Crypto/RistrettoPrivate.swift
+++ b/Sources/Crypto/RistrettoPrivate.swift
@ -0,0 +1,47 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct RistrettoPrivate {
+    let data32: Data32
+
+    init?(_ data: Data32) {
+        guard CryptoUtils.ristrettoPrivateValidate(data.data) else {
+            return nil
+        }
+        self.data32 = data
+    }
+
+    init(skippingValidation data: Data32) {
+        self.data32 = data
+    }
+}
+
+extension RistrettoPrivate: DataConvertibleImpl {
+    typealias Iterator = Data.Iterator
+
+    init?(_ data: Data) {
+        guard let data32 = Data32(data.data) else {
+            return nil
+        }
+        self.init(data32)
+    }
+
+    var data: Data { data32.data }
+}
+
+extension RistrettoPrivate {
+    init?(_ ristrettoPrivate: External_RistrettoPrivate) {
+        self.init(ristrettoPrivate.data)
+    }
+}
+
+extension External_RistrettoPrivate {
+    init(_ ristrettoPrivate: RistrettoPrivate) {
+        self.init()
+        self.data = ristrettoPrivate.data
+    }
+}
--- a/Sources/Crypto/RistrettoPublic.swift
+++ b/Sources/Crypto/RistrettoPublic.swift
@ -0,0 +1,47 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct RistrettoPublic {
+    let data32: Data32
+
+    init?(_ data: Data32) {
+        guard CryptoUtils.ristrettoPublicValidate(data.data) else {
+            return nil
+        }
+        self.data32 = data
+    }
+
+    init(skippingValidation data: Data32) {
+        self.data32 = data
+    }
+}
+
+extension RistrettoPublic: DataConvertibleImpl {
+    typealias Iterator = Data.Iterator
+
+    init?(_ data: Data) {
+        guard let data32 = Data32(data.data) else {
+            return nil
+        }
+        self.init(data32)
+    }
+
+    var data: Data { data32.data }
+}
+
+extension RistrettoPublic {
+    init?(_ ristrettoPublic: External_CompressedRistretto) {
+        self.init(ristrettoPublic.data)
+    }
+}
+
+extension External_CompressedRistretto {
+    init(_ ristrettoPublic: RistrettoPublic) {
+        self.init()
+        self.data = ristrettoPublic.data
+    }
+}
--- a/Sources/Crypto/VersionedCryptoBox.swift
+++ b/Sources/Crypto/VersionedCryptoBox.swift
@ -0,0 +1,88 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+enum VersionedCryptoBoxError: Error {
+    case invalidInput(String)
+    case unsupportedVersion(String)
+}
+
+extension VersionedCryptoBoxError: CustomStringConvertible {
+    var description: String {
+        "Versioned CryptoBox error: " + {
+            switch self {
+            case .invalidInput(let reason):
+                return "Invalid input: \(reason)"
+            case .unsupportedVersion(let reason):
+                return "Unsupported version: \(reason)"
+            }
+        }()
+    }
+}
+
+enum VersionedCryptoBox {
+    static func encrypt(
+        plaintext: Data,
+        publicKey: RistrettoPublic,
+        rng: (@convention(c) (UnsafeMutableRawPointer?) -> UInt64)?,
+        rngContext: Any?
+    ) -> Result<Data, InvalidInputError> {
+        publicKey.asMcBuffer { viewPublicKeyPtr in
+            plaintext.asMcBuffer { plaintextPtr in
+                withMcRngCallback(rng: rng, rngContext: rngContext) { rngCallbackPtr in
+                    Data.make(withMcMutableBuffer: { bufferPtr, errorPtr in
+                        mc_versioned_crypto_box_encrypt(
+                            viewPublicKeyPtr,
+                            plaintextPtr,
+                            rngCallbackPtr,
+                            bufferPtr,
+                            &errorPtr)
+                    }).mapError {
+                        switch $0.errorCode {
+                        case .aead:
+                            return InvalidInputError("\(redacting: $0.description)")
+                        default:
+                            // Safety: mc_versioned_crypto_box_encrypt should not throw
+                            // non-documented errors.
+                            logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    static func decrypt(
+        ciphertext: Data,
+        privateKey: RistrettoPrivate
+    ) -> Result<Data, VersionedCryptoBoxError> {
+        privateKey.asMcBuffer { privateKeyPtr in
+            ciphertext.asMcBuffer { ciphertextPtr in
+                Data.make(withEstimatedLengthMcMutableBuffer: ciphertext.count)
+                { bufferPtr, errorPtr in
+                    mc_versioned_crypto_box_decrypt(
+                        privateKeyPtr,
+                        ciphertextPtr,
+                        bufferPtr,
+                        &errorPtr)
+                }.mapError {
+                    switch $0.errorCode {
+                    case .aead, .invalidInput:
+                        return .invalidInput("\(redacting: $0.description)")
+                    case .unsupportedCryptoBoxVersion:
+                        return .unsupportedVersion("\(redacting: $0.description)")
+                    default:
+                        // Safety: mc_versioned_crypto_box_decrypt should not throw non-documented
+                        // errors.
+                        logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+                    }
+                }
+            }
+        }
+    }
+}
--- a/Sources/Encodings/Base58Coder.swift
+++ b/Sources/Encodings/Base58Coder.swift
@ -0,0 +1,59 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+public enum Base58DecodingResult {
+    case publicAddress(PublicAddress)
+    case paymentRequest(PaymentRequest)
+    case transferPayload(TransferPayload)
+}
+
+public enum Base58Coder {
+    public static func encode(_ publicAddress: PublicAddress) -> String {
+        var wrapper = Printable_PrintableWrapper()
+        wrapper.publicAddress = External_PublicAddress(publicAddress)
+        return wrapper.base58EncodedString()
+    }
+
+    public static func encode(_ paymentRequest: PaymentRequest) -> String {
+        var wrapper = Printable_PrintableWrapper()
+        wrapper.paymentRequest = Printable_PaymentRequest(paymentRequest)
+        return wrapper.base58EncodedString()
+    }
+
+    public static func encode(_ transferPayload: TransferPayload) -> String {
+        var wrapper = Printable_PrintableWrapper()
+        wrapper.transferPayload = Printable_TransferPayload(transferPayload)
+        return wrapper.base58EncodedString()
+    }
+
+    /// - Returns: `nil` when the input is not decodable.
+    public static func decode(_ base58String: String) -> Base58DecodingResult? {
+        guard let wrapper = Printable_PrintableWrapper(base58Encoded: base58String) else {
+            return nil
+        }
+
+        switch wrapper.wrapper {
+        case .publicAddress(let publicAddress):
+            guard let publicAddress = PublicAddress(publicAddress) else {
+                return nil
+            }
+            return .publicAddress(publicAddress)
+        case .paymentRequest(let paymentRequest):
+            guard let paymentRequest = PaymentRequest(paymentRequest) else {
+                return nil
+            }
+            return .paymentRequest(paymentRequest)
+        case .transferPayload(let transferPayload):
+            guard let transferPayload = TransferPayload(transferPayload) else {
+                return nil
+            }
+            return .transferPayload(transferPayload)
+        case .none:
+            return nil
+        }
+    }
+}
--- a/Sources/Encodings/MobUri.swift
+++ b/Sources/Encodings/MobUri.swift
@ -0,0 +1,142 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+public enum MobUri {
+    public enum Payload {
+        case publicAddress(PublicAddress)
+        case paymentRequest(PaymentRequest)
+        case transferPayload(TransferPayload)
+    }
+
+    public static func decode(uri uriString: String) -> Result<Payload, InvalidInputError> {
+        guard let uri = URL(string: uriString) else {
+            logger.info("Could not parse MobURI as URL: \(redacting: uriString)")
+            return .failure(
+                InvalidInputError("Could not parse MobUri as URL: \(redacting: uriString)"))
+        }
+        guard let scheme = uri.scheme else {
+            logger.info("MobUri scheme cannot be empty.")
+            return .failure(InvalidInputError("MobUri scheme cannot be empty."))
+        }
+        guard scheme == McConstants.MOB_URI_SCHEME else {
+            logger.info(
+                "MobUri scheme must be \"\(McConstants.MOB_URI_SCHEME)\". Found: \(scheme)")
+            return .failure(InvalidInputError(
+                "MobUri scheme must be \"\(McConstants.MOB_URI_SCHEME)\". Found: \(scheme)"))
+        }
+
+        return Payload.make(pathComponents: uri.pathComponents)
+    }
+
+    public static func encode(_ publicAddress: PublicAddress) -> String {
+        encode(.publicAddress(publicAddress))
+    }
+
+    public static func encode(_ paymentRequest: PaymentRequest) -> String {
+        encode(.paymentRequest(paymentRequest))
+    }
+
+    public static func encode(_ transferPayload: TransferPayload) -> String {
+        encode(.transferPayload(transferPayload))
+    }
+
+    static func encode(_ payload: Payload) -> String {
+        "\(McConstants.MOB_URI_SCHEME)://\(payload.uriPath)"
+    }
+}
+
+extension MobUri.Payload {
+    static func make(pathComponents: [String]) -> Result<MobUri.Payload, InvalidInputError> {
+        // Foundation.URL returns "/" as the first value in pathComponents, so we normalize by
+        // removing it.
+        guard let firstComponent = pathComponents.first else {
+            return .failure(InvalidInputError("MobUri must have a path."))
+        }
+        guard firstComponent == "/" else {
+            return .failure(InvalidInputError("MobUri must have an absolute path."))
+        }
+        let pathComponents = Array(pathComponents.dropFirst())
+
+        guard pathComponents.count >= 2 else {
+            return .failure(InvalidInputError("MobUri must have at least 2 path components."))
+        }
+        let payloadTypeString = pathComponents[0]
+
+        guard let payloadType = PayloadType(payloadTypeString) else {
+            return .failure(InvalidInputError(
+                "MobUri contains unrecognized payload type: \(payloadTypeString)"))
+        }
+
+        switch payloadType {
+        case .b58:
+            let payloadString = pathComponents[1]
+            guard let decodingResult = Base58Coder.decode(payloadString) else {
+                return .failure(InvalidInputError(
+                    "MobUri payload base-58 decoding failed. Payload: \(redacting: payloadString)"))
+            }
+
+            return .success(MobUri.Payload(decodingResult))
+        }
+    }
+
+    init(_ base58DecodingResult: Base58DecodingResult) {
+        switch base58DecodingResult {
+        case .publicAddress(let publicAddress):
+            self = .publicAddress(publicAddress)
+        case .paymentRequest(let paymentRequest):
+            self = .paymentRequest(paymentRequest)
+        case .transferPayload(let transferPayload):
+            self = .transferPayload(transferPayload)
+        }
+    }
+
+    var payloadType: PayloadType {
+        switch self {
+        case .publicAddress, .paymentRequest, .transferPayload:
+            return .b58
+        }
+    }
+
+    var payloadString: String {
+        switch self {
+        case .publicAddress(let publicAddress):
+            return Base58Coder.encode(publicAddress)
+        case .paymentRequest(let paymentRequest):
+            return Base58Coder.encode(paymentRequest)
+        case .transferPayload(let transferPayload):
+            return Base58Coder.encode(transferPayload)
+        }
+    }
+
+    var uriPath: String {
+        "/\(payloadType)/\(payloadString)"
+    }
+}
+
+extension MobUri.Payload {
+    enum PayloadType {
+        case b58
+
+        init?(_ string: String) {
+            switch string {
+            case "b58":
+                self = .b58
+            default:
+                return nil
+            }
+        }
+    }
+}
+
+extension MobUri.Payload.PayloadType: CustomStringConvertible {
+    var description: String {
+        switch self {
+        case .b58:
+            return "b58"
+        }
+    }
+
+}
--- a/Sources/Encodings/PaymentRequest.swift
+++ b/Sources/Encodings/PaymentRequest.swift
@ -0,0 +1,59 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+public struct PaymentRequest {
+    public let publicAddress: PublicAddress
+    public let value: UInt64?
+    public let memo: String?
+
+    /// # Notes:
+    /// * Providing a `value` of `0` is the same as passing `nil`, meaning no value is specified.
+    /// * Providing an empty string for `memo` is the same as passing `nil`, meaning no memo is
+    ///     specified.
+    public init(publicAddress: PublicAddress, value: UInt64? = nil, memo: String? = nil) {
+        self.publicAddress = publicAddress
+
+        if let value = value, value != 0 {
+            self.value = value
+        } else {
+            self.value = nil
+        }
+
+        if let memo = memo, !memo.isEmpty {
+            self.memo = memo
+        } else {
+            self.memo = nil
+        }
+    }
+}
+
+extension PaymentRequest: Equatable {}
+extension PaymentRequest: Hashable {}
+
+extension PaymentRequest {
+    init?(_ paymentRequest: Printable_PaymentRequest) {
+        guard let publicAddress = PublicAddress(paymentRequest.publicAddress) else {
+            return nil
+        }
+        self.publicAddress = publicAddress
+        self.value = paymentRequest.value != 0 ? paymentRequest.value : nil
+        self.memo = !paymentRequest.memo.isEmpty ? paymentRequest.memo : nil
+    }
+}
+
+extension Printable_PaymentRequest {
+    init(_ paymentRequest: PaymentRequest) {
+        self.init()
+        self.publicAddress = External_PublicAddress(paymentRequest.publicAddress)
+        if let value = paymentRequest.value {
+            self.value = value
+        }
+        if let memo = paymentRequest.memo {
+            self.memo = memo
+        }
+    }
+}
--- a/Sources/Encodings/PrintableWrapper+Base58.swift
+++ b/Sources/Encodings/PrintableWrapper+Base58.swift
@ -0,0 +1,37 @@
+// swiftlint:disable:this file_name
+
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+extension Printable_PrintableWrapper {
+    init?(base58Encoded base58String: String) {
+        guard case .success(let decodedData) =
+            Data.make(withMcMutableBuffer: { bufferPtr, errorPtr in
+                mc_printable_wrapper_b58_decode(base58String, bufferPtr, &errorPtr)
+            })
+        else {
+            logger.warning("PrintableWrapper base-58 decoding failed.")
+            return nil
+        }
+
+        guard let printableWrapper = try? Self(serializedData: decodedData) else {
+            logger.warning("Printable_PrintableWrapper deserialization failed.")
+            return nil
+        }
+
+        self = printableWrapper
+    }
+
+    func base58EncodedString() -> String {
+        let serialized = serializedDataInfallible
+        return serialized.asMcBuffer { bufferPtr in
+            String(mcString: withMcInfallibleReturningOptional {
+                mc_printable_wrapper_b58_encode(bufferPtr)
+            })
+        }
+    }
+}
--- a/Sources/Encodings/TransferPayload.swift
+++ b/Sources/Encodings/TransferPayload.swift
@ -0,0 +1,49 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+public struct TransferPayload {
+    let rootEntropy32: Data32
+    let txOutPublicKey: RistrettoPublic
+    public let memo: String?
+
+    init(rootEntropy: Data32, txOutPublicKey: RistrettoPublic, memo: String? = nil) {
+        self.rootEntropy32 = rootEntropy
+        self.txOutPublicKey = txOutPublicKey
+        self.memo = memo?.isEmpty == false ? memo : nil
+    }
+
+    public var rootEntropy: Data {
+        rootEntropy32.data
+    }
+}
+
+extension TransferPayload: Equatable {}
+extension TransferPayload: Hashable {}
+
+extension TransferPayload {
+    init?(_ transferPayload: Printable_TransferPayload) {
+        guard let rootEntropy = Data32(transferPayload.rootEntropy),
+              let txOutPublicKey = RistrettoPublic(transferPayload.txOutPublicKey.data)
+        else {
+            return nil
+        }
+        self.rootEntropy32 = rootEntropy
+        self.txOutPublicKey = txOutPublicKey
+        self.memo = !transferPayload.memo.isEmpty ? transferPayload.memo : nil
+    }
+}
+
+extension Printable_TransferPayload {
+    init(_ transferPayload: TransferPayload) {
+        self.init()
+        self.rootEntropy = transferPayload.rootEntropy
+        self.txOutPublicKey = External_CompressedRistretto(transferPayload.txOutPublicKey)
+        if let memo = transferPayload.memo {
+            self.memo = memo
+        }
+    }
+}
--- a/Sources/Fog/FogKeyImageChecker.swift
+++ b/Sources/Fog/FogKeyImageChecker.swift
@ -0,0 +1,113 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_arguments multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+struct FogKeyImageChecker {
+    private let serialQueue: DispatchQueue
+    private let fogKeyImageService: FogKeyImageService
+
+    init(fogKeyImageService: FogKeyImageService, targetQueue: DispatchQueue?) {
+        self.serialQueue = DispatchQueue(label: "com.mobilecoin.\(Self.self)", target: targetQueue)
+        self.fogKeyImageService = fogKeyImageService
+    }
+
+    func checkKeyImage(
+        keyImage: KeyImage,
+        nextKeyImageQueryBlockIndex: UInt64 = 0,
+        completion: @escaping (Result<KeyImage.SpentStatus, ConnectionError>) -> Void
+    ) {
+        checkKeyImages(
+            keyImageQueries: [(keyImage, nextKeyImageQueryBlockIndex: nextKeyImageQueryBlockIndex)]
+        ) {
+            completion($0.flatMap { statuses in
+                guard let keyImageStatus = statuses.first else {
+                    return .failure(.invalidServerResponse(
+                        "CheckKeyImage failed to return results: \(statuses)"))
+                }
+                return .success(keyImageStatus)
+            })
+        }
+    }
+
+    func checkKeyImages(
+        keyImageQueries: [KeyImage],
+        maxKeyImagesPerQuery: Int,
+        completion: @escaping (Result<[KeyImage.SpentStatus], ConnectionError>) -> Void
+    ) {
+        checkKeyImages(
+            keyImageQueries: keyImageQueries.map { ($0, nextKeyImageQueryBlockIndex: 0) },
+            maxKeyImagesPerQuery: maxKeyImagesPerQuery,
+            completion: completion)
+    }
+
+    func checkKeyImages(
+        keyImageQueries: [(KeyImage, nextKeyImageQueryBlockIndex: UInt64)],
+        maxKeyImagesPerQuery: Int,
+        completion: @escaping (Result<[KeyImage.SpentStatus], ConnectionError>) -> Void
+    ) {
+        let queryArrays = keyImageQueries.chunked(maxLength: maxKeyImagesPerQuery).map { Array($0) }
+        queryArrays.mapAsync({ chunk, callback in
+            checkKeyImages(keyImageQueries: chunk, completion: callback)
+        }, serialQueue: serialQueue, completion: { result in
+            completion(result.map { $0.flatMap { $0 } })
+        })
+    }
+
+    func checkKeyImages(
+        keyImageQueries: [KeyImage],
+        completion: @escaping (Result<[KeyImage.SpentStatus], ConnectionError>) -> Void
+    ) {
+        checkKeyImages(
+            keyImageQueries: keyImageQueries.map { ($0, nextKeyImageQueryBlockIndex: 0) },
+            completion: completion)
+    }
+
+    func checkKeyImages(
+        keyImageQueries: [(KeyImage, nextKeyImageQueryBlockIndex: UInt64)],
+        completion: @escaping (Result<[KeyImage.SpentStatus], ConnectionError>) -> Void
+    ) {
+        var request = FogLedger_CheckKeyImagesRequest()
+        request.queries = keyImageQueries.map {
+            var query = FogLedger_KeyImageQuery()
+            query.keyImage = External_KeyImage($0.0)
+            query.startBlock = $0.nextKeyImageQueryBlockIndex
+            return query
+        }
+        fogKeyImageService.checkKeyImages(request: request) {
+            completion($0.flatMap {
+                Self.parseResponse(keyImageQueries: keyImageQueries, response: $0)
+            })
+        }
+    }
+
+    private static func parseResponse(
+        keyImageQueries: [(KeyImage, nextKeyImageQueryBlockIndex: UInt64)],
+        response: FogLedger_CheckKeyImagesResponse
+    ) -> Result<[KeyImage.SpentStatus], ConnectionError> {
+        keyImageQueries.map { query in
+            guard let keyImageResult = response.results.first(
+                where: { KeyImage($0.keyImage) == query.0 }) else
+            {
+                return .success(.unspent(knownToBeUnspentBlockCount: response.numBlocks))
+            }
+
+            switch keyImageResult.keyImageResultCodeEnum {
+            case .spent:
+                let spentAtBlock = BlockMetadata(
+                    index: keyImageResult.spentAt,
+                    timestampStatus: keyImageResult.timestampStatus)
+                return .success(.spent(block: spentAtBlock))
+            case .notSpent:
+                return .success(.unspent(knownToBeUnspentBlockCount: response.numBlocks))
+            case .keyImageError, .unused, .UNRECOGNIZED:
+                return .failure(.invalidServerResponse("Fog KeyImage result error: " +
+                    "\(keyImageResult.keyImageResultCodeEnum), response: \(response)"))
+            }
+        }.collectResult()
+    }
+}
--- a/Sources/Fog/FogMerkleProofFetcher.swift
+++ b/Sources/Fog/FogMerkleProofFetcher.swift
@ -0,0 +1,144 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_arguments multiline_function_chains
+// swiftlint:disable closure_body_length
+
+import Foundation
+import LibMobileCoin
+
+enum FogMerkleProofFetcherError: Error {
+    case connectionError(ConnectionError)
+    case outOfBounds(blockCount: UInt64, ledgerTxOutCount: UInt64)
+}
+
+extension FogMerkleProofFetcherError: CustomStringConvertible {
+    var description: String {
+        "Fog Merkle Proof Fetcher error: " + {
+            switch self {
+            case .connectionError(let innerError):
+                return "\(innerError)"
+            case let .outOfBounds(blockCount: blockCount, ledgerTxOutCount: txOutCount):
+                return "Out of bounds: blockCount: \(blockCount), globalTxOutCount: \(txOutCount)"
+            }
+        }()
+    }
+}
+
+struct FogMerkleProofFetcher {
+    private let serialQueue: DispatchQueue
+    private let fogMerkleProofService: FogMerkleProofService
+
+    init(fogMerkleProofService: FogMerkleProofService, targetQueue: DispatchQueue?) {
+        self.serialQueue = DispatchQueue(label: "com.mobilecoin.\(Self.self)", target: targetQueue)
+        self.fogMerkleProofService = fogMerkleProofService
+    }
+
+    func getOutputs(
+        globalIndicesArray: [[UInt64]],
+        merkleRootBlock: UInt64,
+        maxNumIndicesPerQuery: Int,
+        completion: @escaping (
+            Result<[[(TxOut, TxOutMembershipProof)]], FogMerkleProofFetcherError>
+        ) -> Void
+    ) {
+        getOutputs(
+            globalIndices: globalIndicesArray.flatMap { $0 },
+            merkleRootBlock: merkleRootBlock,
+            maxNumIndicesPerQuery: maxNumIndicesPerQuery
+        ) {
+            completion($0.flatMap { allResults in
+                globalIndicesArray.map { globalIndices in
+                    guard let results = allResults[globalIndices] else {
+                        return .failure(.connectionError(.invalidServerResponse(
+                            "Global txout indices not found in GetOutputs reponse. " +
+                            "globalTxOutIndices: \(globalIndices), returned outputs: " +
+                            "\(allResults)")))
+                    }
+                    return .success(results)
+                }.collectResult()
+            })
+        }
+    }
+
+    func getOutputs(
+        globalIndices: [UInt64],
+        merkleRootBlock: UInt64,
+        maxNumIndicesPerQuery: Int,
+        completion: @escaping (
+            Result<[UInt64: (TxOut, TxOutMembershipProof)], FogMerkleProofFetcherError>
+        ) -> Void
+    ) {
+        let globalIndicesArrays =
+            globalIndices.chunked(maxLength: maxNumIndicesPerQuery).map { Array($0) }
+        globalIndicesArrays.mapAsync({ chunk, callback in
+            getOutputs(globalIndices: chunk, merkleRootBlock: merkleRootBlock, completion: callback)
+        }, serialQueue: serialQueue, completion: {
+            completion($0.map { arrayOfOutputMaps in
+                arrayOfOutputMaps.reduce(into: [:]) { outputMapAccum, outputMap in
+                    outputMapAccum.merge(outputMap, uniquingKeysWith: { key1, _ in key1 })
+                }
+            })
+        })
+    }
+
+    func getOutputs(
+        globalIndices: [UInt64],
+        merkleRootBlock: UInt64,
+        completion: @escaping (
+            Result<[UInt64: (TxOut, TxOutMembershipProof)], FogMerkleProofFetcherError>
+        ) -> Void
+    ) {
+        var request = FogLedger_GetOutputsRequest()
+        request.indices = globalIndices
+        request.merkleRootBlock = merkleRootBlock
+        fogMerkleProofService.getOutputs(request: request) {
+            completion(
+                $0.mapError { .connectionError($0) }
+                    .flatMap { Self.parseResponse(response: $0) })
+        }
+    }
+
+    private static func parseResponse(response: FogLedger_GetOutputsResponse)
+        -> Result<[UInt64: (TxOut, TxOutMembershipProof)], FogMerkleProofFetcherError>
+    {
+        response.results.map { outputResult in
+            switch outputResult.resultCodeEnum {
+            case .exists:
+                break
+            case .doesNotExist:
+                return .failure(.outOfBounds(
+                    blockCount: response.numBlocks,
+                    ledgerTxOutCount: response.globalTxoCount))
+            case .outputDatabaseError, .intentionallyUnused, .UNRECOGNIZED:
+                return .failure(.connectionError(.invalidServerResponse(
+                    "FogMerkleProofService.getOutputs result code error: " +
+                        "\(outputResult.resultCodeEnum), response: \(redacting: response)")))
+            }
+
+            let txOut: TxOut
+            switch TxOut.make(outputResult.output) {
+            case .success(let result):
+                txOut = result
+            case .failure(let error):
+                return .failure(.connectionError(.invalidServerResponse(
+                    "FogMerkleProofService.getOutputs returned invalid TxOut. error: \(error)")))
+            }
+
+            let membershipProof: TxOutMembershipProof
+            switch TxOutMembershipProof.make(outputResult.proof) {
+            case .success(let result):
+                membershipProof = result
+            case .failure(let error):
+                return .failure(.connectionError(.invalidServerResponse(
+                    "FogMerkleProofService.getOutputs returned invalid membership proof. error: " +
+                        "\(error)")))
+            }
+
+            return .success((outputResult.index, (txOut, membershipProof)))
+        }.collectResult().map {
+            Dictionary($0, uniquingKeysWith: { key1, _ in key1 })
+        }
+    }
+}
--- a/Sources/Fog/FogUntrustedTxOutFetcher.swift
+++ b/Sources/Fog/FogUntrustedTxOutFetcher.swift
@ -0,0 +1,67 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct FogUntrustedTxOutFetcher {
+    private let fogUntrustedTxOutService: FogUntrustedTxOutService
+
+    init(fogUntrustedTxOutService: FogUntrustedTxOutService) {
+        self.fogUntrustedTxOutService = fogUntrustedTxOutService
+    }
+
+    func getTxOut(
+        outputPublicKey: RistrettoPublic,
+        completion: @escaping (
+            Result<(result: FogLedger_TxOutResult, blockCount: UInt64), ConnectionError>
+        ) -> Void
+    ) {
+        getTxOuts(outputPublicKeys: [outputPublicKey]) {
+            completion($0.flatMap { results, blockCount in
+                guard let result =
+                        results.first(where: { $0.txOutPubkey.data == outputPublicKey.data })
+                else {
+                    logger.info("failure - Fog UntrustedTxOut service failed to " +
+                        "return the requested TxOut: \(redacting: results)")
+                    return .failure(.invalidServerResponse(
+                        "Fog UntrustedTxOut service failed to return the requested TxOut. " +
+                        "\(results)"))
+                }
+                return .success((result, blockCount: blockCount))
+            })
+        }
+    }
+
+    func getTxOuts(
+        outputPublicKeys: [RistrettoPublic],
+        completion:
+            @escaping (
+                Result<(results: [FogLedger_TxOutResult], blockCount: UInt64), ConnectionError>
+            ) -> Void
+    ) {
+        logger.info(
+            "outputPublicKeys: \(redacting: outputPublicKeys.map { $0.hexEncodedString() })")
+        var request = FogLedger_TxOutRequest()
+        request.txOutPubkeys = outputPublicKeys.map { External_CompressedRistretto($0) }
+        fogUntrustedTxOutService.getTxOuts(request: request) {
+            completion($0.flatMap { response in
+                let resultPairs = response.results.map { ($0.txOutPubkey.data, $0) }
+                let publicKeyToResult =
+                    Dictionary(resultPairs, uniquingKeysWith: { key1, _ in key1 })
+
+                let outputPublicKeys = outputPublicKeys.map { $0.data }
+                guard let results = publicKeyToResult[outputPublicKeys] else {
+                    logger.info("failure - Fog UntrustedTxOut service failed to " +
+                        "return the requested TxOuts: \(redacting: response.results)")
+                    return .failure(.invalidServerResponse(
+                        "Fog UntrustedTxOut service failed to return the requested TxOuts. " +
+                        "\(response)"))
+                }
+
+                return .success((results, blockCount: response.numBlocks))
+            })
+        }
+    }
+}
--- a/Sources/Fog/FogViewKeyScanner.swift
+++ b/Sources/Fog/FogViewKeyScanner.swift
@ -0,0 +1,74 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+final class FogViewKeyScanner {
+    private let accountKey: AccountKey
+    private let fogBlockService: FogBlockService
+
+    init(accountKey: AccountKey, fogBlockService: FogBlockService) {
+        self.accountKey = accountKey
+        self.fogBlockService = fogBlockService
+    }
+
+    func viewKeyScanBlocks(
+        blockRanges: [Range<UInt64>],
+        completion: @escaping (Result<[KnownTxOut], ConnectionError>) -> Void
+    ) {
+        logger.info(
+            "Fetching block ranges: \(blockRanges.map { "[\($0.lowerBound), \($0.upperBound))" })",
+            logFunction: false)
+
+        fetchBlocksTxOuts(ranges: blockRanges) {
+            completion($0.map { blocksTxOuts in
+                logger.info(
+                    "View key scanning blocks: " +
+                        "\(blockRanges.map { "[\($0.lowerBound), \($0.upperBound))" }) " +
+                        "containing \(blocksTxOuts.count) TxOuts",
+                    logFunction: false)
+
+                let foundTxOuts = blocksTxOuts.compactMap {
+                    $0.decrypt(accountKey: self.accountKey)
+                }
+                logger.info(
+                    "View key scanning missed blocks found \(redacting: foundTxOuts.count) TxOuts",
+                    logFunction: false)
+                return foundTxOuts
+            })
+        }
+    }
+
+    func fetchBlocksTxOuts(
+        ranges: [Range<UInt64>],
+        completion: @escaping (Result<[LedgerTxOut], ConnectionError>) -> Void
+    ) {
+        var request = FogLedger_BlockRequest()
+        request.rangeValues = ranges
+        fogBlockService.getBlocks(request: request) {
+            completion($0.flatMap { response in
+                response.blocks.flatMap { responseBlock -> [Result<LedgerTxOut, ConnectionError>] in
+                    let globalIndexStart =
+                        responseBlock.globalTxoCount - UInt64(responseBlock.outputs.count)
+                    return responseBlock.outputs.enumerated().map { outputIndex, output in
+                        guard let partialTxOut = PartialTxOut(output) else {
+                            let errorMessage =
+                                "Fog Block service returned invalid TxOut: \(output)"
+                            logger.error(errorMessage, logFunction: false)
+                            return .failure(.invalidServerResponse(errorMessage))
+                        }
+
+                        return .success(LedgerTxOut(
+                            partialTxOut,
+                            globalIndex: globalIndexStart + UInt64(outputIndex),
+                            block: responseBlock.metadata))
+                    }
+                }.collectResult()
+            })
+        }
+    }
+}
--- a/Sources/Fog/Report/FogReportManager.swift
+++ b/Sources/Fog/Report/FogReportManager.swift
@ -0,0 +1,72 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+final class FogReportManager {
+    private let inner: SerialDispatchLock<Inner>
+
+    private let serialQueue: DispatchQueue
+    private let serviceProvider: ServiceProvider
+
+    init(serviceProvider: ServiceProvider, targetQueue: DispatchQueue?) {
+        self.inner = .init(Inner(targetQueue: targetQueue), targetQueue: targetQueue)
+        self.serialQueue = DispatchQueue(label: "com.mobilecoin.\(Self.self)", target: targetQueue)
+        self.serviceProvider = serviceProvider
+    }
+
+    func reportResponse(
+        for reportUrl: FogUrl,
+        completion: @escaping (Result<Report_ReportResponse, ConnectionError>) -> Void
+    ) {
+        logger.info("reportUrl: \(reportUrl.url)")
+        serviceProvider.fogReportService(for: reportUrl) { reportService in
+            self.inner.accessAsync {
+                let reportServer = $0.reportServer(for: reportUrl)
+                reportServer.reports(reportService: reportService, completion: completion)
+            }
+        }
+    }
+
+    func reportResponse(
+        for reportUrl: FogUrl,
+        reportParams: [(reportId: String, desiredMinPubkeyExpiry: UInt64)],
+        completion: @escaping (Result<Report_ReportResponse, ConnectionError>) -> Void
+    ) {
+        logger.info("reportUrl: \(reportUrl.url), reportParams: \(reportParams)")
+        serviceProvider.fogReportService(for: reportUrl) { reportService in
+            self.inner.accessAsync {
+                let reportServer = $0.reportServer(for: reportUrl)
+                reportServer.reports(
+                    reportService: reportService,
+                    reportParams: reportParams,
+                    completion: completion)
+            }
+        }
+    }
+}
+
+extension FogReportManager {
+    private struct Inner {
+        private let sharedSerialExclusionQueue: DispatchQueue
+
+        private var networkConfigToServer: [GrpcChannelConfig: FogReportServer] = [:]
+
+        init(targetQueue: DispatchQueue?) {
+            self.sharedSerialExclusionQueue = DispatchQueue(
+                label: "com.mobilecoin.\(FogReportServer.self)",
+                target: targetQueue)
+        }
+
+        mutating func reportServer(for reportUrl: FogUrl) -> FogReportServer {
+            let config = GrpcChannelConfig(url: reportUrl)
+            return networkConfigToServer[config] ?? {
+                let reportServer = FogReportServer(serialExclusionQueue: sharedSerialExclusionQueue)
+                networkConfigToServer[config] = reportServer
+                return reportServer
+            }()
+        }
+    }
+}
--- a/Sources/Fog/Report/FogReportServer.swift
+++ b/Sources/Fog/Report/FogReportServer.swift
@ -0,0 +1,137 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable array_init
+
+import Foundation
+import LibMobileCoin
+
+final class FogReportServer {
+    private let inner: SerialDispatchLock<Inner>
+
+    private let serialConnectionQueue: SerialCallbackQueue
+
+    init(serialExclusionQueue: DispatchQueue) {
+        self.inner = .init(Inner(), serialExclusionQueue: serialExclusionQueue)
+        self.serialConnectionQueue = .init(targetQueue: serialExclusionQueue)
+    }
+
+    func reports(
+        reportService: FogReportService,
+        completion: @escaping (Result<Report_ReportResponse, ConnectionError>) -> Void
+    ) {
+        fetchReports(reportService: reportService, completion: completion)
+    }
+
+    func reports(
+        reportService: FogReportService,
+        reportParams: [(reportId: String, desiredMinPubkeyExpiry: UInt64)],
+        completion: @escaping (Result<Report_ReportResponse, ConnectionError>) -> Void
+    ) {
+        logger.info("reportParams: \(reportParams)")
+        inner.accessAsync {
+            if let reportResponse =
+                $0.cachedReportResponse(satisfyingReportParams: reportParams.map { $0 })
+            {
+                completion(.success(reportResponse))
+            } else {
+                self.fetchReports(
+                    reportService: reportService,
+                    reportParams: reportParams,
+                    completion: completion)
+            }
+        }
+    }
+
+    private func fetchReports(
+        reportService: FogReportService,
+        completion: @escaping (Result<Report_ReportResponse, ConnectionError>) -> Void
+    ) {
+        serialConnectionQueue.append({ callback in
+            self.doFetchReports(reportService: reportService, completion: callback)
+        }, completion: completion)
+    }
+
+    private func fetchReports(
+        reportService: FogReportService,
+        reportParams: [(reportId: String, desiredMinPubkeyExpiry: UInt64)],
+        completion: @escaping (Result<Report_ReportResponse, ConnectionError>) -> Void
+    ) {
+        logger.info("reportParams: \(reportParams)")
+        serialConnectionQueue.append({ callback in
+            // Now that we have the serialConnectionQueue lock, check again if there's a cached
+            // report response that satisfies the reportParams.
+            self.inner.accessAsync {
+                if let reportResponse =
+                    $0.cachedReportResponse(satisfyingReportParams: reportParams.map { $0 })
+                {
+                    callback(.success(reportResponse))
+                } else {
+                    // Otherwise, continue with fetching from the network.
+                    self.doFetchReports(reportService: reportService, completion: callback)
+                }
+            }
+        }, completion: completion)
+    }
+
+    private func doFetchReports(
+        reportService: FogReportService,
+        completion: @escaping (Result<Report_ReportResponse, ConnectionError>) -> Void
+    ) {
+        reportService.getReports(request: Report_ReportRequest()) {
+            guard let reportResponse = $0.successOr(completion: completion) else { return }
+
+            // Save report response before releasing the serialConnectionQueue
+            // lock. This ensures that, if there's another request waiting, it
+            // will have access to the report response we just fetched.
+            self.cacheReportResponse(reportResponse) {
+                completion(.success(reportResponse))
+            }
+        }
+    }
+
+    private func cacheReportResponse(
+        _ reportResponse: Report_ReportResponse,
+        completion: @escaping () -> Void
+    ) {
+        inner.accessAsync {
+            $0.cacheReportResponse(reportResponse)
+
+            completion()
+        }
+    }
+}
+
+extension FogReportServer {
+    private struct Inner {
+        private var cachedReportResponse: Report_ReportResponse?
+
+        func cachedReportResponse(
+            satisfyingReportParams reportParams: [(reportId: String, minPubkeyExpiry: UInt64)]
+        ) -> Report_ReportResponse? {
+            logger.info("reportParams: \(reportParams)")
+            guard let reportResponse = cachedReportResponse else {
+                return nil
+            }
+            guard reportResponse.isValid(reportParams: reportParams) else {
+                logger.info("report response invalid - reportParams: \(reportParams)")
+                return nil
+            }
+            logger.info("report response valid - reportParams: \(reportParams)")
+            return reportResponse
+        }
+
+        mutating func cacheReportResponse(_ reportResponse: Report_ReportResponse) {
+            cachedReportResponse = reportResponse
+        }
+    }
+}
+
+extension Report_ReportResponse {
+    fileprivate func isValid(reportParams: [(reportId: String, minPubkeyExpiry: UInt64)]) -> Bool {
+        reportParams.allSatisfy { reportId, minPubkeyExpiry in
+            reports.contains { $0.fogReportID == reportId && $0.pubkeyExpiry >= minPubkeyExpiry }
+        }
+    }
+}
--- a/Sources/Fog/Report/FogResolver.swift
+++ b/Sources/Fog/Report/FogResolver.swift
@ -0,0 +1,72 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+final class FogResolver {
+    private let ptr: OpaquePointer
+
+    convenience init() {
+        self.init(attestation: Attestation())
+    }
+
+    convenience init(
+        attestation: Attestation,
+        reportUrlsAndResponses: [(FogUrl, Report_ReportResponse)]
+    ) {
+        self.init(attestation: attestation)
+        for (reportUrl, response) in reportUrlsAndResponses {
+            addReportResponse(reportUrl: reportUrl, reportResponse: response)
+        }
+    }
+
+    private init(attestation: Attestation) {
+        logger.info("attestation: \(attestation)")
+        let verifier = AttestationVerifier(attestation: attestation)
+        // Safety: mc_fog_resolver_create should never return nil.
+        self.ptr = verifier.withUnsafeOpaquePointer { verifierPtr in
+            withMcInfallible {
+                mc_fog_resolver_create(verifierPtr)
+            }
+        }
+    }
+
+    deinit {
+        mc_fog_resolver_free(ptr)
+    }
+
+    func withUnsafeOpaquePointer<R>(_ body: (OpaquePointer) throws -> R) rethrows -> R {
+        try body(ptr)
+    }
+
+    private func addReportResponse(reportUrl: FogUrl, reportResponse: Report_ReportResponse) {
+        logger.info("")
+        let serializedReportResponse = reportResponse.serializedDataInfallible
+        serializedReportResponse.asMcBuffer { reportResponsePtr in
+            switch withMcError({ errorPtr in
+                mc_fog_resolver_add_report_response(
+                    ptr,
+                    reportUrl.url.absoluteString,
+                    reportResponsePtr,
+                    &errorPtr)
+            }) {
+            case .success:
+                break
+            case .failure(let error):
+                switch error.errorCode {
+                case .invalidInput:
+                    // Safety: mc_fog_resolver_add_report_response shouldn't fail deserialization
+                    // since we just serialized it and roundtrip serialization should always
+                    // succeed.
+                    logger.fatalError("\(error)")
+                default:
+                    // Safety: mc_fog_resolver_add_report_response should not throw non-documented
+                    // errors.
+                    logger.fatalError("Unhandled LibMobileCoin error: \(redacting: error)")
+                }
+            }
+        }
+    }
+}
--- a/Sources/Fog/Report/FogResolverManager.swift
+++ b/Sources/Fog/Report/FogResolverManager.swift
@ -0,0 +1,75 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_arguments
+
+import Foundation
+import LibMobileCoin
+
+final class FogResolverManager {
+    private let serialQueue: DispatchQueue
+    private let reportAttestation: Attestation
+    private let reportManager: FogReportManager
+
+    init(
+        fogReportAttestation: Attestation,
+        serviceProvider: ServiceProvider,
+        targetQueue: DispatchQueue?
+    ) {
+        self.serialQueue = DispatchQueue(label: "com.mobilecoin.\(Self.self)", target: targetQueue)
+        self.reportAttestation = fogReportAttestation
+        self.reportManager =
+            FogReportManager(serviceProvider: serviceProvider, targetQueue: targetQueue)
+    }
+
+    func fogResolver(
+        addresses: [PublicAddress],
+        completion: @escaping (Result<FogResolver, ConnectionError>) -> Void
+    ) {
+        logger.info("addresses: \(addresses.map { "\(redacting: $0)" })")
+        let reportUrls = Set(addresses.compactMap { $0.fogReportUrl })
+        reportUrls.mapAsync({ reportUrl, callback in
+            reportManager.reportResponse(for: reportUrl) {
+                callback($0.map { response in
+                    (reportUrl, response)
+                })
+            }
+        }, serialQueue: serialQueue, completion: {
+            completion($0.map { reportUrlsAndResponses in
+                FogResolver(
+                    attestation: self.reportAttestation,
+                    reportUrlsAndResponses: reportUrlsAndResponses)
+            })
+        })
+    }
+
+    func fogResolver(
+        addresses: [PublicAddress],
+        desiredMinPubkeyExpiry: UInt64,
+        completion: @escaping (Result<FogResolver, ConnectionError>) -> Void
+    ) {
+        logger.info("\(addresses.map { "\(redacting: $0)" }), " +
+            "desiredMinPubkeyExpiry: \(desiredMinPubkeyExpiry)")
+        let fogInfos = addresses.compactMap { $0.fogInfo }
+
+        let reportUrlsToFogInfos = Dictionary(grouping: fogInfos, by: { $0.reportUrl })
+        let reportUrlsToReportParams = reportUrlsToFogInfos.mapValues { fogInfos in
+            fogInfos.map { ($0.reportId, desiredMinPubkeyExpiry) }
+        }
+        reportUrlsToReportParams.mapAsync({ reportUrlToReportParams, callback in
+            let (reportUrl, reportParams) = reportUrlToReportParams
+            reportManager.reportResponse(for: reportUrl, reportParams: reportParams) {
+                callback($0.map { response in
+                    (reportUrl, response)
+                })
+            }
+        }, serialQueue: serialQueue, completion: {
+            completion($0.map { reportUrlsAndResponses in
+                FogResolver(
+                    attestation: self.reportAttestation,
+                    reportUrlsAndResponses: reportUrlsAndResponses)
+            })
+        })
+    }
+}
--- a/Sources/Fog/View/DefaultFogQueryScalingStrategy.swift
+++ b/Sources/Fog/View/DefaultFogQueryScalingStrategy.swift
@ -0,0 +1,23 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+struct DefaultFogQueryScalingStrategy: FogQueryScalingStrategy {
+    private static let MIN_SEARCH_KEYS_PER_QUERY = 10
+    private static let MAX_SEARCH_KEYS_PER_QUERY = 200
+    private static let SCALING_MULTIPLIER: Double = 3
+
+    func create() -> AnyInfiniteIterator<PositiveInt> {
+        var next = Self.MIN_SEARCH_KEYS_PER_QUERY
+        return AnyInfiniteIterator {
+            guard let current = PositiveInt(next) else {
+                // Safety: `next` should always be positive if we only ever increase in value.
+                logger.fatalError("PositiveInt.init returned nil. value: \(next)")
+            }
+            next = min(Int(Double(next) * Self.SCALING_MULTIPLIER), Self.MAX_SEARCH_KEYS_PER_QUERY)
+            return current
+        }
+    }
+}
--- a/Sources/Fog/View/FogQueryScalingStrategy.swift
+++ b/Sources/Fog/View/FogQueryScalingStrategy.swift
@ -0,0 +1,9 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+protocol FogQueryScalingStrategy {
+    func create() -> AnyInfiniteIterator<PositiveInt>
+}
--- a/Sources/Fog/View/FogRng.swift
+++ b/Sources/Fog/View/FogRng.swift
@ -0,0 +1,140 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+enum FogRngError: Error {
+    case invalidKey(String)
+    case unsupportedCryptoBoxVersion(String)
+}
+
+extension FogRngError: CustomStringConvertible {
+    var description: String {
+        "Fog Kex Rng error: " + {
+            switch self {
+            case .invalidKey(let reason):
+                return "Invalid key: \(reason)"
+            case .unsupportedCryptoBoxVersion(let reason):
+                return "Unsupported CryptoBox version: \(reason)"
+            }
+        }()
+    }
+}
+
+final class FogRng {
+    static func make(fogRngKey: FogRngKey, accountKey: AccountKey) -> Result<FogRng, FogRngError> {
+        make(fogRngKey: fogRngKey, subaddressViewPrivateKey: accountKey.subaddressViewPrivateKey)
+    }
+
+    static func make(fogRngKey: FogRngKey, subaddressViewPrivateKey: RistrettoPrivate)
+        -> Result<FogRng, FogRngError>
+    {
+        subaddressViewPrivateKey.asMcBuffer { viewPrivateKeyPtr in
+            fogRngKey.pubkey.asMcBuffer { pubkeyPtr in
+                withMcError { errorPtr in
+                    mc_fog_rng_create(viewPrivateKeyPtr, pubkeyPtr, fogRngKey.version, &errorPtr)
+                }.mapError {
+                    switch $0.errorCode {
+                    case .invalidInput:
+                        return .invalidKey("\(redacting: $0.description)")
+                    case .unsupportedCryptoBoxVersion:
+                        return .unsupportedCryptoBoxVersion("\(redacting: $0.description)")
+                    default:
+                        // Safety: mc_fog_rng_create should not throw non-documented errors.
+                        logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+                    }
+                }.map { ptr in
+                    FogRng(ptr)
+                }
+            }
+        }
+    }
+
+    /// - Returns: `.failure` when the input is not deserializable.
+    static func make(serializedData: Data) -> Result<FogRng, FogRngError> {
+        serializedData.asMcBuffer { dataPtr in
+            withMcError { errorPtr in
+                mc_fog_rng_deserialize_proto(dataPtr, &errorPtr)
+            }.mapError {
+                switch $0.errorCode {
+                case .invalidInput:
+                    return .invalidKey("\(redacting: $0.description)")
+                case .unsupportedCryptoBoxVersion:
+                    return .unsupportedCryptoBoxVersion("\(redacting: $0.description)")
+                default:
+                    // Safety: mc_fog_rng_deserialize_proto should not throw non-documented errors.
+                    logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+                }
+            }
+        }.map { ptr in
+            FogRng(ptr)
+        }
+    }
+
+    private let ptr: OpaquePointer
+    private let outputSize: Int
+
+    private init(_ ptr: OpaquePointer) {
+        self.ptr = ptr
+        self.outputSize = withMcInfallibleReturningOptional {
+            let len = mc_fog_rng_get_output_len(ptr)
+            return len >= 0 ? len : nil
+        }
+    }
+
+    deinit {
+        mc_fog_rng_free(ptr)
+    }
+
+    var serializedData: Data {
+        Data(withMcMutableBufferInfallible: { bufferPtr in
+            mc_fog_rng_serialize_proto(ptr, bufferPtr)
+        })
+    }
+
+    func clone() -> FogRng {
+        // Safety: mc_fog_rng_clone should never return nil.
+        FogRng(withMcInfallible { mc_fog_rng_clone(ptr) })
+    }
+
+    var index: UInt64 {
+        withMcInfallibleReturningOptional {
+            let res = mc_fog_rng_index(ptr)
+            return res >= 0 ? UInt64(res) : nil
+        }
+    }
+
+    var output: Data {
+        Data(withFixedLengthMcMutableBufferInfallible: outputSize) { bufferPtr in
+            mc_fog_rng_peek(ptr, bufferPtr)
+        }
+    }
+
+    func outputs(count: Int) -> [Data] {
+        let rngCopy = clone()
+        return (0..<count).map { _ in
+            rngCopy.advance()
+        }
+    }
+
+    @discardableResult
+    func advance() -> Data {
+        Data(withFixedLengthMcMutableBufferInfallible: outputSize) { bufferPtr in
+            mc_fog_rng_advance(ptr, bufferPtr)
+        }
+    }
+}
+
+extension FogRng {
+    static func make(fogRngPubkey: KexRng_KexRngPubkey, accountKey: AccountKey)
+        -> Result<FogRng, FogRngError>
+    {
+        make(
+            fogRngKey: FogRngKey(fogRngPubkey),
+            subaddressViewPrivateKey: accountKey.subaddressViewPrivateKey)
+    }
+}
--- a/Sources/Fog/View/FogRngKey.swift
+++ b/Sources/Fog/View/FogRngKey.swift
@ -0,0 +1,34 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct FogRngKey {
+    let pubkey: Data
+    let version: UInt32
+
+    init(pubkey: Data, version: UInt32) {
+        self.pubkey = pubkey
+        self.version = version
+    }
+}
+
+extension FogRngKey: Equatable {}
+extension FogRngKey: Hashable {}
+
+extension FogRngKey {
+    init(_ pubkey: KexRng_KexRngPubkey) {
+        self.pubkey = pubkey.pubkey
+        self.version = pubkey.version
+    }
+}
+
+extension KexRng_KexRngPubkey {
+    init(_ fogRngKey: FogRngKey) {
+        self.init()
+        self.pubkey = fogRngKey.pubkey
+        self.version = fogRngKey.version
+    }
+}
--- a/Sources/Fog/View/FogRngSet.swift
+++ b/Sources/Fog/View/FogRngSet.swift
@ -0,0 +1,349 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+final class FogRngSet {
+    private var ingestInvocationIdToRngTrackers: [Int64: RngTracker] = [:]
+    private(set) var rngRecordsKnownBlockCount: UInt64 = 0
+
+    var earliestRngRecordStartBlockIndex: UInt64? {
+        ingestInvocationIdToRngTrackers.values.map { $0.startBlockIndex }.min()
+    }
+
+    var knownBlockCount: UInt64 {
+        ingestInvocationIdToRngTrackers.values.map { $0.knownBlockCount }
+            .reduce(rngRecordsKnownBlockCount, min)
+    }
+
+    func searchAttempt(
+        targetBlockCount: UInt64?,
+        numOutputs: PositiveInt,
+        minOutputsPerSelectedRng: Int
+    ) -> FogRngSetSearchAttempt {
+        // Max rngs we can select while maintaining the requested minimum outputs per selected rng.
+        let maxRngs = 0 < minOutputsPerSelectedRng && minOutputsPerSelectedRng <= numOutputs.value
+            ? numOutputs.value / minOutputsPerSelectedRng : numOutputs.value
+
+        let selectedRngs =
+            selectRngsForSearch(requestedBlockCount: targetBlockCount, maxRngs: maxRngs)
+        guard !selectedRngs.isEmpty else {
+            logger.info(
+                "No active Fog rngs as of block count: \(rngRecordsKnownBlockCount)",
+                logFunction: false)
+            return FogRngSetSearchAttempt()
+        }
+
+        // Num of outputs to generate per selected rng.
+        let outputsPerRng = numOutputs.value / selectedRngs.count
+        let numRemainderOutputs = numOutputs.value % selectedRngs.count
+
+        let ingestInvocationIdAndRngSearchAttempt =
+            selectedRngs.enumerated().map { i, rngPair -> (Int64, FogRngSearchAttempt) in
+                let (ingestInvocationId, rngTracker) = rngPair
+                let numOutputs = outputsPerRng + (i < numRemainderOutputs ? 1 : 0)
+                let rngSearchAttempt = rngTracker.searchAttempt(numOutputs: numOutputs)
+                return (ingestInvocationId, rngSearchAttempt)
+            }
+        return FogRngSetSearchAttempt(
+            ingestInvocationIdToRngSearchAttempt: Dictionary(
+                uniqueKeysWithValues: ingestInvocationIdAndRngSearchAttempt))
+    }
+
+    private func selectRngsForSearch(requestedBlockCount: UInt64?, maxRngs: Int)
+        -> [Int64: RngTracker]
+    {
+        // Filter for rngs that are still active.
+        var eligibleRngTrackers = ingestInvocationIdToRngTrackers.filter { $0.value.active }
+
+        if let requestedBlockCount = requestedBlockCount {
+            // Filter for rngs that haven't already successfully processed the requested number of
+            // blocks.
+            //
+            // This is how we handle TxOut search pagination. If we repeatedly perform search
+            // attempts with the same `requestedBlockCount` (e.g. when performing a single balance
+            // check), eventually all rngs will have a `knownBlockCount` of at least
+            // `requestedBlockCount`.
+            eligibleRngTrackers = eligibleRngTrackers.filter {
+                $0.value.knownBlockCount < requestedBlockCount
+            }
+        }
+
+        return Dictionary(uniqueKeysWithValues: Array(eligibleRngTrackers.prefix(maxRngs)))
+    }
+
+    func processRngs(queryResponse: FogView_QueryResponse, accountKey: AccountKey)
+        -> Result<(), ConnectionError>
+    {
+        processRngRecords(
+            queryResponse.rngs,
+            highestProcessedBlockCount: queryResponse.highestProcessedBlockCount,
+            accountKey: accountKey
+        ).map {
+            processDecommissionedRngs(queryResponse.decommissionedIngestInvocations)
+        }
+    }
+
+    private func processRngRecords(
+        _ rngRecords: [FogView_RngRecord],
+        highestProcessedBlockCount: UInt64,
+        accountKey: AccountKey
+    ) -> Result<(), ConnectionError> {
+        for rngRecord in rngRecords
+            where ingestInvocationIdToRngTrackers[rngRecord.ingestInvocationID] == nil
+        {
+            logger.info(
+                "New RngRecord: ingestInvocationID: \(rngRecord.ingestInvocationID), pubkey: " +
+                    "\(rngRecord.pubkey.pubkey.hexEncodedString()), version: " +
+                    "\(rngRecord.pubkey.version), startBlockIndex: \(rngRecord.startBlock)",
+                logFunction: false)
+
+            switch RngTracker.make(rngRecord: rngRecord, accountKey: accountKey) {
+            case .success(let rngTracker):
+                ingestInvocationIdToRngTrackers[rngRecord.ingestInvocationID] = rngTracker
+            case .failure(let error):
+                switch error {
+                case .invalidKey(let reason):
+                    let errorMessage = "Fog View returned invalid key rng key: \(reason)"
+                    logger.error(errorMessage, logFunction: false)
+                    return .failure(.invalidServerResponse(errorMessage))
+                case .unsupportedCryptoBoxVersion(let reason):
+                    let errorMessage = "Fog View returned unsupported kex rng version: \(reason)"
+                    logger.error(errorMessage, logFunction: false)
+                    return .failure(.outdatedClient(errorMessage))
+                }
+            }
+        }
+
+        // Record that Fog has told us about all rngs that could possibly have been active up to
+        // `highestProcessedBlockCount` (while accounting for the possibility that we already have
+        // more up-to-date information already).
+        if highestProcessedBlockCount > rngRecordsKnownBlockCount {
+            logger.info(
+                "FogRngSet updating rngRecordsKnownBlockCount from \(rngRecordsKnownBlockCount) " +
+                    "to \(highestProcessedBlockCount)",
+                logFunction: false)
+            rngRecordsKnownBlockCount = highestProcessedBlockCount
+        }
+
+        return .success(())
+    }
+
+    private func processDecommissionedRngs(
+        _ decommissionedRngs: [FogView_DecommissionedIngestInvocation]
+    ) {
+        for decommissionedRng in decommissionedRngs {
+            if let rngTracker =
+                ingestInvocationIdToRngTrackers[decommissionedRng.ingestInvocationID]
+            {
+                logger.info(
+                    "Rng decommissioned: ingestInvocationID: " +
+                        "\(decommissionedRng.ingestInvocationID), lastIngestedBlockIndex: " +
+                        "\(decommissionedRng.lastIngestedBlock)",
+                    logFunction: false)
+                rngTracker.decommissioned = true
+            } else {
+                logger.error(
+                    "Fog View decommissioned unknown ingestInvocation. ingestInvocationID: " +
+                        "\(decommissionedRng.ingestInvocationID), lastIngestedBlock: " +
+                        "\(decommissionedRng.lastIngestedBlock), current " +
+                        "rngRecordsKnownBlockCount: \(rngRecordsKnownBlockCount)",
+                    logFunction: false)
+            }
+        }
+    }
+
+    func processTxOutSearchResults(
+        queryResponse: FogView_QueryResponse,
+        rngSetSearchAttempt: FogRngSetSearchAttempt
+    ) -> Result<[FogView_TxOutSearchResult], ConnectionError> {
+        processTxOutSearchResults(
+            queryResponse.txOutSearchResults,
+            highestProcessedBlockCount: queryResponse.highestProcessedBlockCount,
+            rngSetSearchAttempt: rngSetSearchAttempt)
+    }
+
+    private func processTxOutSearchResults(
+        _ txOutSearchResults: [FogView_TxOutSearchResult],
+        highestProcessedBlockCount: UInt64,
+        rngSetSearchAttempt: FogRngSetSearchAttempt
+    ) -> Result<[FogView_TxOutSearchResult], ConnectionError> {
+        let searchKeyToTxOutResult = Dictionary(
+            txOutSearchResults.map { ($0.searchKey, $0) },
+            uniquingKeysWith: { key1, _ in key1 })
+
+        return rngSetSearchAttempt.ingestInvocationIdToRngSearchAttempt
+            .map { ingestInvocationId, rngSearchAttempt
+                    -> Result<[FogView_TxOutSearchResult], ConnectionError> in
+                guard let rngTracker = ingestInvocationIdToRngTrackers[ingestInvocationId] else {
+                    // This condition is considered a programming error and mean `searchAttempt` was
+                    // created using a different `FogRngSet` instance. We silently fail here, since
+                    // we know we're still in a valid, internally-consistent state.
+                    logger.assertionFailure("RngTracker not found for rngKey in search attempt. " +
+                        "ingestInvocationId: \(ingestInvocationId)")
+                    return .success([])
+                }
+
+                // Filter for only the outputs we searched for.
+                let rngSearchKeyToTxOutResult: [Data: FogView_TxOutSearchResult] = Dictionary(
+                    rngSearchAttempt.searchKeys.map { $0.bytes }.compactMap { searchKeyBytes in
+                        guard let txOutResult = searchKeyToTxOutResult[searchKeyBytes] else {
+                            logger.error(
+                                "Searched key not in search results. searched key: " +
+                                    "\(searchKeyBytes.hexEncodedString())",
+                                logFunction: false)
+                            return nil
+                        }
+                        return (searchKeyBytes, txOutResult)
+                    },
+                    uniquingKeysWith: { key1, _ in key1 })
+
+                return rngTracker.processSearchKeyResults(
+                    rngSearchKeyToTxOutResult: rngSearchKeyToTxOutResult,
+                    highestProcessedBlockCount: highestProcessedBlockCount)
+            }.collectResult().map {
+                $0.flatMap { $0 }
+            }
+    }
+}
+
+private final class RngTracker {
+    let rng: FogRng
+    let startBlockIndex: UInt64
+
+    /// Whether this RNG is still in use by Fog.
+    ///
+    /// If an RNG has been decommissioned, then all `TxOut`'s corresponding to the RNG are available
+    /// for immediate retrieval from Fog. This means that once we encounter a search miss we can
+    /// stop considering the RNG when generating search keys for a `TxOut` search.
+    var decommissioned = false
+
+    /// Whether we have found all `TxOut`'s for this RNG.
+    ///
+    /// An RNG is active until the RNG has been both decommissioned and we've encountered at least
+    /// one search miss since.
+    var active = true
+
+    /// Number of blocks for which all `TxOut`s for this RNG are known.
+    ///
+    /// Represents the number of blocks for which we can guarantee that all `TxOut`'s corresponding
+    /// to this RNG have been found. Put another way, we can guarantee that the next output from
+    /// this RNG has no corresponding `TxOut` within this block range.
+    ///
+    /// This starts at either `0` or the RNG's `startBlock`. Each time we do a search, if we
+    /// encounter at least one miss (a.k.a. a `TxOut` is not found for an output from this RNG),
+    /// then we set this value to the `highestProcessedBlockCount` returned in the search response.
+    var knownBlockCount: UInt64
+
+    init(rng: FogRng, startBlockIndex: UInt64) {
+        self.rng = rng
+        self.startBlockIndex = startBlockIndex
+        // We assign a blockCount with the value of a blockIndex because, if X is the block index of
+        // the first block that the rng is active, then X is also the number of blocks that came
+        // before that block, hence our knownBlockCount. E.g. if the startBlockIndex is 1, 1 is also
+        // the number of blocks before block index 1.
+        self.knownBlockCount = startBlockIndex
+    }
+
+    func searchAttempt(numOutputs: Int) -> FogRngSearchAttempt {
+        let outputs = rng.outputs(count: numOutputs)
+        let searchKeys = outputs.map { FogSearchKey($0) }
+
+        // Note: converting directly from blockCount to blockIndex is valid here.
+        return FogRngSearchAttempt(searchKeys: searchKeys, startFromBlockIndex: knownBlockCount)
+    }
+
+    func processSearchKeyResults(
+        rngSearchKeyToTxOutResult: [Data: FogView_TxOutSearchResult],
+        highestProcessedBlockCount: UInt64
+    ) -> Result<[FogView_TxOutSearchResult], ConnectionError> {
+        var foundTxOutResults: [FogView_TxOutSearchResult] = []
+
+        searchResultLoop: while true {
+            let output = rng.output
+
+            guard let txOutResult = rngSearchKeyToTxOutResult[output] else {
+                // Either we've found all the outputs we searched for or we've processed txos since
+                // this search attempt was made. Either way, if the next output we need wasn't one
+                // of the ones searched for or wasn't in the search results, then there's nothing
+                // else we can do with this rng.
+                logger.debug(
+                    "Next rng output not found in searched keys. rng output: " +
+                        "0x\(redacting: output.hexEncodedString())",
+                    logFunction: false)
+                break
+            }
+
+            switch txOutResult.resultCodeEnum {
+            case .found:
+                foundTxOutResults.append(txOutResult)
+                rng.advance()
+            case .notFound:
+                // The search key failed to return a `TxOut` during this search attempt.
+
+                if highestProcessedBlockCount > knownBlockCount {
+                    // `highestProcessedBlockCount` is the number of blocks that fog guarantees it
+                    // finished processing when performing the search, so we store
+                    // `highestProcessedBlockCount` as the `knownBlockCount` for this RNG on the
+                    // assumption that if we encountered a miss for this RNG, then there are no more
+                    // `TxOut`'s that can be found for this RNG in the first
+                    // `highestProcessedBlockCount` number of blocks in the ledger.
+                    knownBlockCount = highestProcessedBlockCount
+                }
+
+                // Break on the first miss
+                break searchResultLoop
+            case .rateLimited:
+                let errorMessage = "Fog View error response: rateLimited"
+                logger.warning(errorMessage, logFunction: false)
+                return .failure(.serverRateLimited(errorMessage))
+            case .badSearchKey, .internalError, .intentionallyUnused, .UNRECOGNIZED:
+                let errorMessage = "Fog view error response: \(txOutResult.resultCodeEnum), " +
+                    "txOutResult.searchKey: \(redacting: txOutResult.searchKey)"
+                logger.error(errorMessage, logFunction: false)
+                return .failure(.invalidServerResponse(errorMessage))
+            }
+        }
+
+        return .success(foundTxOutResults)
+    }
+}
+
+extension RngTracker {
+    static func make(rngRecord: FogView_RngRecord, accountKey: AccountKey)
+        -> Result<RngTracker, FogRngError>
+    {
+        FogRng.make(fogRngPubkey: rngRecord.pubkey, accountKey: accountKey).map { rng in
+            RngTracker(rng: rng, rngRecord: rngRecord)
+        }
+    }
+
+    convenience init(rng: FogRng, rngRecord: FogView_RngRecord) {
+        self.init(rng: rng, startBlockIndex: rngRecord.startBlock)
+    }
+}
+
+struct FogRngSetSearchAttempt {
+    fileprivate let ingestInvocationIdToRngSearchAttempt: [Int64: FogRngSearchAttempt]
+
+    fileprivate init(ingestInvocationIdToRngSearchAttempt: [Int64: FogRngSearchAttempt]? = nil) {
+        self.ingestInvocationIdToRngSearchAttempt = ingestInvocationIdToRngSearchAttempt ?? [:]
+    }
+
+    var searchKeys: [FogSearchKey] {
+        ingestInvocationIdToRngSearchAttempt.values.flatMap { $0.searchKeys }
+    }
+
+    var lowestStartFromBlockIndex: UInt64 {
+        ingestInvocationIdToRngSearchAttempt.values.map { $0.startFromBlockIndex }.min() ?? 0
+    }
+}
+
+private struct FogRngSearchAttempt {
+    let searchKeys: [FogSearchKey]
+    let startFromBlockIndex: UInt64
+}
--- a/Sources/Fog/View/FogSearchKey.swift
+++ b/Sources/Fog/View/FogSearchKey.swift
@ -0,0 +1,16 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+struct FogSearchKey {
+    let bytes: Data
+
+    init(_ bytes: Data) {
+        self.bytes = bytes
+    }
+}
+
+extension FogSearchKey: Equatable {}
+extension FogSearchKey: Hashable {}
--- a/Sources/Fog/View/FogView+TxOutFetcher.swift
+++ b/Sources/Fog/View/FogView+TxOutFetcher.swift
@ -0,0 +1,123 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable closure_body_length multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+import os
+
+extension FogView {
+    struct TxOutFetcher {
+        private let serialQueue: DispatchQueue
+        private let fogView: ReadWriteDispatchLock<FogView>
+        private let accountKey: AccountKey
+        private let fogViewService: FogViewService
+        private let fogQueryScalingStrategy: FogQueryScalingStrategy
+
+        init(
+            fogView: ReadWriteDispatchLock<FogView>,
+            accountKey: AccountKey,
+            fogViewService: FogViewService,
+            fogQueryScalingStrategy: FogQueryScalingStrategy,
+            targetQueue: DispatchQueue?
+        ) {
+            self.serialQueue = DispatchQueue(
+                label: "com.mobilecoin.\(FogView.self).\(Self.self)",
+                target: targetQueue)
+            self.fogView = fogView
+            self.accountKey = accountKey
+            self.fogViewService = fogViewService
+            self.fogQueryScalingStrategy = fogQueryScalingStrategy
+        }
+
+        private var allRngTxOutsFoundBlockCount: UInt64 {
+            fogView.readSync { $0.allRngTxOutsFoundBlockCount }
+        }
+
+        func fetchTxOuts(
+            partialResultsWithWriteLock: @escaping ([KnownTxOut]) -> Void,
+            completion: @escaping (Result<(), ConnectionError>) -> Void
+        ) {
+            performSearchRound(
+                targetBlockCount: nil,
+                queryScaling: nil,
+                partialResultsWithWriteLock: partialResultsWithWriteLock,
+                completion: completion)
+        }
+
+        private func performSearchRound(
+            targetBlockCount: UInt64?,
+            queryScaling: AnyInfiniteIterator<PositiveInt>?,
+            partialResultsWithWriteLock: @escaping ([KnownTxOut]) -> Void,
+            completion: @escaping (Result<(), ConnectionError>) -> Void
+        ) {
+            logger.info("Querying Fog View...", logFunction: false)
+
+            let queryScaling = queryScaling ?? fogQueryScalingStrategy.create()
+            let numOutputs = queryScaling.next()
+            let (requestWrapper, searchAttempt) = fogView.readSync {
+                $0.queryRequest(targetBlockCount: targetBlockCount, numOutputs: numOutputs)
+            }
+            fogViewService.query(requestWrapper: requestWrapper) {
+                let result = $0.flatMap { response in
+                    self.fogView.writeSync {
+                        $0.processQueryResponse(
+                            response,
+                            searchAttempt: searchAttempt,
+                            accountKey: self.accountKey
+                        ).map { processResult -> UInt64? in
+                            if !searchAttempt.searchKeys.isEmpty {
+                                partialResultsWithWriteLock(processResult.newTxOuts)
+                            }
+                            return processResult.nextRoundTargetBlockCount
+                        }
+                    }
+                }
+
+                switch result {
+                case .success(let nextRoundTargetBlockCount):
+                    if let nextRoundTargetBlockCount = nextRoundTargetBlockCount {
+                        // Reset query scaling if we didn't search for anything last round.
+                        let queryScaling = !searchAttempt.searchKeys.isEmpty ? queryScaling : nil
+
+                        // Do another search round
+                        self.performSearchRound(
+                            targetBlockCount: nextRoundTargetBlockCount,
+                            queryScaling: queryScaling,
+                            partialResultsWithWriteLock: partialResultsWithWriteLock,
+                            completion: completion)
+                    } else {
+                        // Search complete
+                        completion(.success(()))
+                    }
+                case .failure(let error):
+                    completion(.failure(error))
+                }
+            }
+        }
+    }
+}
+
+extension FogView_QueryResponse: CustomRedactingStringConvertible {
+    var redactingDescription: String {
+        let hits = txOutSearchResults.filter { $0.resultCodeEnum == .found }
+        return """
+            FogView_QueryResponse:
+            rng record count: \(rngs.count)
+            TxOutResult count: \(redacting: txOutSearchResults.count)
+            TxOutResult success count: \(redacting: hits.count)
+            highestProcessedBlockCount: \(highestProcessedBlockCount)
+            highestProcessedBlockSignatureTimestamp: \(highestProcessedBlockSignatureTimestamp) \
+            \(Date(timeIntervalSince1970: TimeInterval(highestProcessedBlockSignatureTimestamp)))
+            decommissionedRngs: \(decommissionedIngestInvocations)
+            missedBlockRanges.count: \(missedBlockRanges.count)
+            missedBlockRanges: \(missedBlockRanges)
+            nextStartFromUserEventId: \(nextStartFromUserEventID)
+            lastKnownBlockCount: \(lastKnownBlockCount)
+            lastKnownBlockCumulativeTxoCount: \(lastKnownBlockCumulativeTxoCount)
+            txOutResults result codes: \(redacting: txOutSearchResults.map { $0.resultCode })
+            """
+    }
+}
--- a/Sources/Fog/View/FogView.swift
+++ b/Sources/Fog/View/FogView.swift
@ -0,0 +1,193 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+final class FogView {
+    private let rngSet = FogRngSet()
+    private(set) var unscannedMissedBlocksRanges: [Range<UInt64>] = []
+
+    /// See `FogUserEvent` in the Fog repo for a list of user events.
+    private(set) var nextStartFromUserEventId: Int64 = 0
+
+    var allRngTxOutsFoundBlockCount: UInt64 {
+        rngSet.knownBlockCount
+    }
+
+    var allRngRecordsKnownBlockCount: UInt64 {
+        rngSet.rngRecordsKnownBlockCount
+    }
+
+    func queryRequest(targetBlockCount: UInt64?, numOutputs: PositiveInt)
+        -> (FogViewQueryRequestWrapper, FogSearchAttempt)
+    {
+        let rngSetSearchAttempt = rngSet.searchAttempt(
+            targetBlockCount: targetBlockCount,
+            numOutputs: numOutputs,
+            minOutputsPerSelectedRng: min(2, numOutputs.value))
+        let searchAttempt = FogSearchAttempt(
+            rngSetSearchAttempt: rngSetSearchAttempt,
+            targetBlockCount: targetBlockCount)
+
+        var wrapper = FogViewQueryRequestWrapper()
+        wrapper.requestAad.startFromUserEventID = nextStartFromUserEventId
+        wrapper.requestAad.startFromBlockIndex = rngSetSearchAttempt.lowestStartFromBlockIndex
+        wrapper.request.getTxos = rngSetSearchAttempt.searchKeys.map { $0.bytes }
+
+        logger.info(
+            "Fog view query params: startFromUserEventID: " +
+            "\(wrapper.requestAad.startFromUserEventID), startFromBlockIndex: " +
+            "\(wrapper.requestAad.startFromBlockIndex)",
+            logFunction: false)
+
+        return (wrapper, searchAttempt)
+    }
+
+    func processQueryResponse(
+        _ queryResponse: FogView_QueryResponse,
+        searchAttempt: FogSearchAttempt,
+        accountKey: AccountKey
+    ) -> Result<(newTxOuts: [KnownTxOut], nextRoundTargetBlockCount: UInt64?), ConnectionError> {
+        logger.info("Processing Fog View query response...", logFunction: false)
+
+        return rngSet.processRngs(queryResponse: queryResponse, accountKey: accountKey).map {
+            processMissedBlockRanges(queryResponse.missedBlockRanges)
+
+            if queryResponse.nextStartFromUserEventID > nextStartFromUserEventId {
+                // We set this only after we've processed the info in `QueryResponse` that's
+                // considered an event, which currently includes `NewRngRecord`,
+                // `DecommissionIngestInvocation`, and `MissingBlocks`. (See `FogUserEvent` in the
+                // Fog repo for the canonical list.)
+                nextStartFromUserEventId = queryResponse.nextStartFromUserEventID
+            }
+        }.flatMap {
+            rngSet.processTxOutSearchResults(
+                queryResponse: queryResponse,
+                rngSetSearchAttempt: searchAttempt.rngSetSearchAttempt)
+        }.flatMap { searchResults in
+            searchResults.map { searchResult in
+                Self.decryptSearchResult(searchResult, accountKey: accountKey)
+            }.collectResult()
+        }.flatMap { txOutRecords in
+            txOutRecords.map { txOutRecord in
+                LedgerTxOut.make(txOutRecord: txOutRecord, viewKey: accountKey.viewPrivateKey)
+            }.collectResult()
+        }.map { txOuts in
+            let foundTxOuts = Self.ownedTxOuts(validating: txOuts, accountKey: accountKey)
+
+            // After the first call we know the current number of blocks processed by the fog
+            // ingest server, so we'll use that to try to build a complete view of the ledger
+            // for our account up to this number of blocks. We keep using this
+            // `targetBlockCount` because the ledger is always growing and we have to stop and
+            // declare the balance check finished at some point.
+            let targetBlockCount =
+                searchAttempt.targetBlockCount ?? queryResponse.highestProcessedBlockCount
+
+            let performAdditionalSearchRounds = allRngTxOutsFoundBlockCount < targetBlockCount
+            let nextRoundTargetBlockCount = performAdditionalSearchRounds ? targetBlockCount : nil
+
+            return (foundTxOuts, nextRoundTargetBlockCount)
+        }
+    }
+
+    private func processMissedBlockRanges(_ missedBlockRanges: [FogCommon_BlockRange]) {
+        var missedBlocks = missedBlockRanges.map { $0.range }
+        if let earliestRngStartBlockIndex = rngSet.earliestRngRecordStartBlockIndex {
+            missedBlocks = missedBlocks.compactMap { range in
+                // Check that we don't view key scan missed blocks that occur before the first
+                // RngRecord's startBlock. This is a workaround for Fog Ingest needing to mark the
+                // blocks before the first run of Fog Ingest as missed blocks.
+                //
+                // This can be removed when Fog provides a guarantee that it won't report the blocks
+                // before Fog Ingest was run for the first time as missed.
+                guard range.lowerBound >= earliestRngStartBlockIndex else {
+                    if range.upperBound <= earliestRngStartBlockIndex {
+                        // Entire missed block range is before the earliest RngRecord's startBlock.
+                        return nil
+                    } else {
+                        // Part of missed block range is before the ealiest RngRecord's startBlock,
+                        // so we modify the missed blocks range.
+                        return earliestRngStartBlockIndex..<range.upperBound
+                    }
+                }
+                return range
+            }
+        }
+
+        unscannedMissedBlocksRanges.append(contentsOf: missedBlocks)
+    }
+
+    func markBlocksAsScanned(blockRanges: [Range<UInt64>]) {
+        for range in blockRanges {
+            unscannedMissedBlocksRanges.removeAll(where: { $0 == range })
+        }
+    }
+
+    private static func decryptSearchResult(
+        _ searchResult: FogView_TxOutSearchResult,
+        accountKey: AccountKey
+    ) -> Result<FogView_TxOutRecord, ConnectionError> {
+        FogViewUtils.decryptTxOutRecord(
+            ciphertext: searchResult.ciphertext,
+            accountKey: accountKey
+        ).mapError { error in
+            switch error {
+            case .invalidInput:
+                let errorMessage = "Could not decrypt TxOut returned from Fog View, ciphertext: " +
+                    "\(redacting: searchResult.ciphertext.base64EncodedString()), error: " +
+                    "\(error)"
+                logger.error(errorMessage)
+                return .invalidServerResponse(errorMessage)
+            case .unsupportedVersion:
+                let errorMessage = "Could not decrypt TxOut returned from Fog View, ciphertext: " +
+                    "\(redacting: searchResult.ciphertext.base64EncodedString()), error: " +
+                    "\(error)"
+                logger.error(errorMessage)
+                return .outdatedClient(errorMessage)
+            }
+        }
+    }
+
+    /// Filters out TxOuts that don't belong to this account.
+    private static func ownedTxOuts(
+        validating txOuts: [LedgerTxOut],
+        accountKey: AccountKey
+    ) -> [KnownTxOut] {
+        let ownedTxOuts = txOuts.compactMap { txOut -> KnownTxOut? in
+            guard let knownTxOut = txOut.decrypt(accountKey: accountKey) else {
+                logger.warning(
+                    "TxOut received from Fog View is not owned by this account. txOut: " +
+                    "\(redacting: txOut.targetKey.data.hexEncodedString())",
+                    logFunction: false)
+                return nil
+            }
+            return knownTxOut
+        }
+        return ownedTxOuts
+    }
+}
+
+struct FogSearchAttempt {
+    fileprivate let rngSetSearchAttempt: FogRngSetSearchAttempt
+    fileprivate let targetBlockCount: UInt64?
+
+    var searchKeys: [FogSearchKey] { rngSetSearchAttempt.searchKeys }
+}
+
+extension LedgerTxOut {
+    fileprivate static func make(txOutRecord: FogView_TxOutRecord, viewKey: RistrettoPrivate)
+        -> Result<LedgerTxOut, ConnectionError>
+    {
+        guard let ledgerTxOut = LedgerTxOut(txOutRecord, viewKey: viewKey) else {
+            let errorMessage = "Invalid TxOut returned from Fog View. TxOutRecord: " +
+                "\(redacting: txOutRecord.serializedDataInfallible.base64EncodedString())"
+            logger.error(errorMessage)
+            return .failure(.invalidServerResponse(errorMessage))
+        }
+        return .success(ledgerTxOut)
+    }
+}
--- a/Sources/Fog/View/FogViewUtils.swift
+++ b/Sources/Fog/View/FogViewUtils.swift
@ -0,0 +1,39 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+enum FogViewUtils {
+    static func encryptTxOutRecord(
+        txOutRecord: FogView_TxOutRecord,
+        publicAddress: PublicAddress,
+        rng: (@convention(c) (UnsafeMutableRawPointer?) -> UInt64)?,
+        rngContext: Any?
+    ) -> Result<Data, InvalidInputError> {
+        VersionedCryptoBox.encrypt(
+            plaintext: txOutRecord.serializedDataInfallible,
+            publicKey: publicAddress.viewPublicKeyTyped,
+            rng: rng,
+            rngContext: rngContext)
+    }
+
+    static func decryptTxOutRecord(
+        ciphertext: Data,
+        accountKey: AccountKey
+    ) -> Result<FogView_TxOutRecord, VersionedCryptoBoxError> {
+        VersionedCryptoBox.decrypt(
+            ciphertext: ciphertext,
+            privateKey: accountKey.subaddressViewPrivateKey
+        ).flatMap { decrypted in
+            guard let txOutRecord = try? FogView_TxOutRecord(serializedData: decrypted) else {
+                return .failure(.invalidInput("FogView_TxOutRecord deserialization failed. " +
+                    "serializedData: \(redacting: decrypted.base64EncodedString())"))
+            }
+            return .success(txOutRecord)
+        }
+    }
+}
--- a/Sources/Ledger/BlockMetadata.swift
+++ b/Sources/Ledger/BlockMetadata.swift
@ -0,0 +1,48 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+public struct BlockMetadata {
+    public let index: UInt64
+
+    let timestampStatus: TimestampStatus?
+    public var timestamp: Date? {
+        switch timestampStatus {
+        case .known(timestamp: let timestamp):
+            return timestamp
+        case .none, .unavailable, .temporarilyUnknown:
+            return nil
+        }
+    }
+
+    init(index: UInt64, timestamp: Date?) {
+        let timestampStatus: TimestampStatus?
+        if let timestamp = timestamp {
+            timestampStatus = .known(timestamp: timestamp)
+        } else {
+            timestampStatus = nil
+        }
+        self.init(index: index, timestampStatus: timestampStatus)
+    }
+
+    init(index: UInt64, timestampStatus: TimestampStatus?) {
+        self.index = index
+        self.timestampStatus = timestampStatus
+    }
+}
+
+extension BlockMetadata: Equatable {}
+extension BlockMetadata: Hashable {}
+
+extension BlockMetadata {
+    enum TimestampStatus {
+        case known(timestamp: Date)
+        case unavailable
+        case temporarilyUnknown
+    }
+}
+
+extension BlockMetadata.TimestampStatus: Equatable {}
+extension BlockMetadata.TimestampStatus: Hashable {}
--- a/Sources/Ledger/KeyImage.swift
+++ b/Sources/Ledger/KeyImage.swift
@ -0,0 +1,69 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct KeyImage {
+    let data32: Data32
+
+    init(_ data: Data32) {
+        self.data32 = data
+    }
+
+    enum SpentStatus {
+        case spent(block: BlockMetadata)
+        case unspent(knownToBeUnspentBlockCount: UInt64)
+
+        var nextKeyImageQueryBlockIndex: UInt64 {
+            switch self {
+            case .spent:
+                return 0
+            case .unspent(let knownToBeUnspentBlockCount):
+                return knownToBeUnspentBlockCount
+            }
+        }
+
+        /// - Returns: `nil` when `blockCount` exceeds our knowledge about the spent status.
+        func status(atBlockCount blockCount: UInt64) -> SpentStatus? {
+            switch self {
+            case .spent(block: let spentAtBlock):
+                guard spentAtBlock.index < blockCount else {
+                    return nil
+                }
+                return .spent(block: spentAtBlock)
+            case .unspent(knownToBeUnspentBlockCount: let knownToBeUnspentBlockCount):
+                guard knownToBeUnspentBlockCount >= blockCount else {
+                    return nil
+                }
+                return .unspent(knownToBeUnspentBlockCount: blockCount)
+            }
+        }
+    }
+}
+
+extension KeyImage: DataConvertibleImpl {
+    typealias Iterator = Data.Iterator
+
+    init?(_ data: Data) {
+        guard let data32 = Data32(data.data) else {
+            return nil
+        }
+        self.init(data32)
+    }
+
+    var data: Data { data32.data }
+}
+
+extension KeyImage {
+    init?(_ keyImage: External_KeyImage) {
+        self.init(keyImage.data)
+    }
+}
+
+extension External_KeyImage {
+    init(_ keyImage: KeyImage) {
+        self.init(keyImage.data32)
+    }
+}
--- a/Sources/Ledger/KeyImageSpentTracker.swift
+++ b/Sources/Ledger/KeyImageSpentTracker.swift
@ -0,0 +1,28 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+final class KeyImageSpentTracker {
+    let keyImage: KeyImage
+
+    var spentStatus: KeyImage.SpentStatus
+
+    init(_ keyImage: KeyImage) {
+        self.keyImage = keyImage
+        self.spentStatus = .unspent(knownToBeUnspentBlockCount: 0)
+    }
+
+    var isSpent: Bool {
+        if case .spent = spentStatus {
+            return true
+        } else {
+            return false
+        }
+    }
+
+    var nextKeyImageQueryBlockIndex: UInt64 {
+        spentStatus.nextKeyImageQueryBlockIndex
+    }
+}
--- a/Sources/Ledger/KnownTxOut.swift
+++ b/Sources/Ledger/KnownTxOut.swift
@ -0,0 +1,40 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+struct KnownTxOut: TxOutProtocol {
+    private let ledgerTxOut: LedgerTxOut
+    let value: UInt64
+    let keyImage: KeyImage
+
+    init?(_ ledgerTxOut: LedgerTxOut, accountKey: AccountKey) {
+        
+        guard let value = ledgerTxOut.value(accountKey: accountKey),
+              let keyImage = ledgerTxOut.keyImage(accountKey: accountKey),
+              let commitment = TxOutUtils.reconstructCommitment(
+                                                   maskedValue: ledgerTxOut.maskedValue,
+                                                   publicKey: ledgerTxOut.publicKey,
+                                                   viewPrivateKey:accountKey.viewPrivateKey)
+        else {
+            return nil
+        }
+        
+        self.commitment = commitment
+        self.ledgerTxOut = ledgerTxOut
+        self.value = value
+        self.keyImage = keyImage
+    }
+
+    var commitment: Data32
+    var maskedValue: UInt64 { ledgerTxOut.maskedValue }
+    var targetKey: RistrettoPublic { ledgerTxOut.targetKey }
+    var publicKey: RistrettoPublic { ledgerTxOut.publicKey }
+    var block: BlockMetadata { ledgerTxOut.block }
+    var globalIndex: UInt64 { ledgerTxOut.globalIndex }
+}
+
+extension KnownTxOut: Equatable {}
+extension KnownTxOut: Hashable {}
+
--- a/Sources/Ledger/LedgerTxOut.swift
+++ b/Sources/Ledger/LedgerTxOut.swift
@ -0,0 +1,43 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct LedgerTxOut: TxOutProtocol {
+    private let txOut: PartialTxOut
+    let globalIndex: UInt64
+    let block: BlockMetadata
+
+    init(_ txOut: PartialTxOut, globalIndex: UInt64, block: BlockMetadata) {
+        self.txOut = txOut
+        self.globalIndex = globalIndex
+        self.block = block
+    }
+
+    var commitment: Data32 { txOut.commitment }
+    var maskedValue: UInt64 { txOut.maskedValue }
+    var targetKey: RistrettoPublic { txOut.targetKey }
+    var publicKey: RistrettoPublic { txOut.publicKey }
+
+    func decrypt(accountKey: AccountKey) -> KnownTxOut? {
+        KnownTxOut(self, accountKey: accountKey)
+    }
+}
+
+extension LedgerTxOut: Equatable {}
+extension LedgerTxOut: Hashable {}
+
+extension LedgerTxOut {
+    init?(_ txOutRecord: FogView_TxOutRecord, viewKey: RistrettoPrivate) {
+        guard let partialTxOut = PartialTxOut(txOutRecord, viewKey: viewKey) else {
+            return nil
+        }
+        let globalIndex = txOutRecord.txOutGlobalIndex
+        let block = BlockMetadata(
+            index: txOutRecord.blockIndex,
+            timestamp: txOutRecord.timestampDate)
+        self.init(partialTxOut, globalIndex: globalIndex, block: block)
+    }
+}
--- a/Sources/Ledger/PartialTxOut.swift
+++ b/Sources/Ledger/PartialTxOut.swift
@ -0,0 +1,60 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct PartialTxOut: TxOutProtocol {
+    let commitment: Data32
+    let maskedValue: UInt64
+    let targetKey: RistrettoPublic
+    let publicKey: RistrettoPublic
+}
+
+extension PartialTxOut: Equatable {}
+extension PartialTxOut: Hashable {}
+
+extension PartialTxOut {
+    init(_ txOut: TxOut) {
+        self.init(
+            commitment: txOut.commitment,
+            maskedValue: txOut.maskedValue,
+            targetKey: txOut.targetKey,
+            publicKey: txOut.publicKey)
+    }
+}
+
+extension PartialTxOut {
+    init?(_ txOut: External_TxOut) {
+        guard let commitment = Data32(txOut.amount.commitment.data),
+              let targetKey = RistrettoPublic(txOut.targetKey.data),
+              let publicKey = RistrettoPublic(txOut.publicKey.data)
+        else {
+            return nil
+        }
+        self.init(
+            commitment: commitment,
+            maskedValue: txOut.amount.maskedValue,
+            targetKey: targetKey,
+            publicKey: publicKey)
+    }
+
+    init?(_ txOutRecord: FogView_TxOutRecord, viewKey: RistrettoPrivate) {
+        guard let targetKey = RistrettoPublic(txOutRecord.txOutTargetKeyData),
+              let publicKey = RistrettoPublic(txOutRecord.txOutPublicKeyData),
+              let commitment = TxOutUtils.reconstructCommitment(
+                                                    maskedValue: txOutRecord.txOutAmountMaskedValue,
+                                                    publicKey: publicKey,
+                                                    viewPrivateKey: viewKey)
+        else {
+            return nil
+        }
+
+        self.init(
+            commitment: commitment,
+            maskedValue: txOutRecord.txOutAmountMaskedValue,
+            targetKey: targetKey,
+            publicKey: publicKey)
+    }
+}
--- a/Sources/Ledger/TxOut.swift
+++ b/Sources/Ledger/TxOut.swift
@ -0,0 +1,83 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct TxOut: TxOutProtocol {
+    fileprivate let proto: External_TxOut
+
+    let commitment: Data32
+    let targetKey: RistrettoPublic
+    let publicKey: RistrettoPublic
+
+    /// - Returns: `nil` when the input is not deserializable.
+    init?(serializedData: Data) {
+        guard let proto = try? External_TxOut(serializedData: serializedData) else {
+            logger.warning(
+                "External_TxOut deserialization failed. serializedData: " +
+                    "\(redacting: serializedData.base64EncodedString())",
+                logFunction: false)
+            return nil
+        }
+
+        switch TxOut.make(proto) {
+        case .success(let txOut):
+            self = txOut
+        case .failure(let error):
+            logger.warning(
+                "External_TxOut deserialization failed. serializedData: " +
+                    "\(redacting: serializedData.base64EncodedString()), error: \(error)",
+                logFunction: false)
+            return nil
+        }
+    }
+
+    var serializedData: Data {
+        proto.serializedDataInfallible
+    }
+
+    var maskedValue: UInt64 { proto.amount.maskedValue }
+    var encryptedFogHint: Data { proto.eFogHint.data }
+}
+
+extension TxOut: Equatable {}
+extension TxOut: Hashable {}
+
+extension TxOut {
+    static func make(_ proto: External_TxOut) -> Result<TxOut, InvalidInputError> {
+        guard let commitment = Data32(proto.amount.commitment.data) else {
+            return .failure(
+                InvalidInputError("Failed parsing External_TxOut: invalid commitment format"))
+        }
+        guard let targetKey = RistrettoPublic(proto.targetKey.data) else {
+            return .failure(
+                InvalidInputError("Failed parsing External_TxOut: invalid target key format"))
+        }
+        guard let publicKey = RistrettoPublic(proto.publicKey.data) else {
+            return .failure(
+                InvalidInputError("Failed parsing External_TxOut: invalid public key format"))
+        }
+        return .success(
+            TxOut(proto: proto, commitment: commitment, targetKey: targetKey, publicKey: publicKey))
+    }
+
+    private init(
+        proto: External_TxOut,
+        commitment: Data32,
+        targetKey: RistrettoPublic,
+        publicKey: RistrettoPublic
+    ) {
+        self.proto = proto
+        self.commitment = commitment
+        self.targetKey = targetKey
+        self.publicKey = publicKey
+    }
+}
+
+extension External_TxOut {
+    init(_ txOut: TxOut) {
+        self = txOut.proto
+    }
+}
--- a/Sources/Ledger/TxOutMembershipProof.swift
+++ b/Sources/Ledger/TxOutMembershipProof.swift
@ -0,0 +1,30 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct TxOutMembershipProof {
+    let serializedData: Data
+
+    static func make(serializedData: Data) -> Result<TxOutMembershipProof, InvalidInputError> {
+        .success(TxOutMembershipProof(serializedData: serializedData))
+    }
+
+    private init(serializedData: Data) {
+        self.serializedData = serializedData
+    }
+}
+
+extension TxOutMembershipProof: Equatable {}
+extension TxOutMembershipProof: Hashable {}
+
+extension TxOutMembershipProof {
+    static func make(_ txOutMembershipProof: External_TxOutMembershipProof)
+        -> Result<TxOutMembershipProof, InvalidInputError>
+    {
+        let serializedData = txOutMembershipProof.serializedDataInfallible
+        return TxOutMembershipProof.make(serializedData: serializedData)
+    }
+}
--- a/Sources/Ledger/TxOutProtocol.swift
+++ b/Sources/Ledger/TxOutProtocol.swift
@ -0,0 +1,66 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+protocol TxOutProtocol {
+    var commitment: Data32 { get } 
+    var maskedValue: UInt64 { get }
+    var targetKey: RistrettoPublic { get }
+    var publicKey: RistrettoPublic { get }
+}
+
+extension TxOutProtocol {
+    func matches(accountKey: AccountKey) -> Bool {
+        TxOutUtils.matchesSubaddress(
+            targetKey: targetKey,
+            publicKey: publicKey,
+            viewPrivateKey: accountKey.viewPrivateKey,
+            subaddressSpendPrivateKey: accountKey.subaddressSpendPrivateKey)
+    }
+
+    func matchesAnySubaddress(accountKey: AccountKey) -> Bool {
+        TxOutUtils.matchesAnySubaddress(
+            maskedValue: maskedValue,
+            publicKey: publicKey,
+            viewPrivateKey: accountKey.viewPrivateKey)
+    }
+
+    func subaddressSpentPublicKey(viewPrivateKey: RistrettoPrivate) -> RistrettoPublic {
+        TxOutUtils.subaddressSpentPublicKey(
+            targetKey: targetKey,
+            publicKey: publicKey,
+            viewPrivateKey: viewPrivateKey)
+    }
+
+    /// - Returns: `nil` when `accountKey` cannot unmask value, either because `accountKey` does not
+    ///     own `TxOut` or because ` TxOut` values are incongruent.
+    func value(accountKey: AccountKey) -> UInt64? {
+        TxOutUtils.value(
+            maskedValue: maskedValue,
+            publicKey: publicKey,
+            viewPrivateKey: accountKey.viewPrivateKey)
+    }
+
+    /// - Returns: `nil` when a valid `KeyImage` cannot be constructed, either because `accountKey`
+    ///     does not own `TxOut` or because `TxOut` values are incongruent.
+    func keyImage(accountKey: AccountKey) -> KeyImage? {
+        TxOutUtils.keyImage(
+            targetKey: targetKey,
+            publicKey: publicKey,
+            viewPrivateKey: accountKey.viewPrivateKey,
+            subaddressSpendPrivateKey: accountKey.subaddressSpendPrivateKey)
+    }
+}
+
+extension FogView_TxOutRecord {
+    init(_ txOut: TxOutProtocol) {
+        self.init()
+        self.txOutAmountCommitmentData = txOut.commitment.data
+        self.txOutAmountMaskedValue = txOut.maskedValue
+        self.txOutTargetKeyData = txOut.targetKey.data
+        self.txOutPublicKeyData = txOut.publicKey.data
+    }
+}
--- a/Sources/Ledger/TxOutUtils.swift
+++ b/Sources/Ledger/TxOutUtils.swift
@ -0,0 +1,259 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable closure_body_length
+
+import Foundation
+import LibMobileCoin
+
+enum TxOutUtils {
+    static func matchesAnySubaddress(
+        maskedValue: UInt64,
+        publicKey: RistrettoPublic,
+        viewPrivateKey: RistrettoPrivate
+    ) -> Bool {
+        var mcAmount = McTxOutAmount(masked_value: maskedValue)
+        return publicKey.asMcBuffer { publicKeyPtr in
+            viewPrivateKey.asMcBuffer { viewPrivateKeyPtr in
+                var matches = false
+                // Safety: mc_tx_out_matches_any_subaddress is infallible when preconditions are
+                // upheld.
+                withMcInfallible {
+                    mc_tx_out_matches_any_subaddress(
+                        &mcAmount,
+                        publicKeyPtr,
+                        viewPrivateKeyPtr,
+                        &matches)
+                }
+                return matches
+            }
+        }
+    }
+
+    static func matchesSubaddress(
+        targetKey: RistrettoPublic,
+        publicKey: RistrettoPublic,
+        viewPrivateKey: RistrettoPrivate,
+        subaddressSpendPrivateKey: RistrettoPrivate
+    ) -> Bool {
+        targetKey.asMcBuffer { targetKeyBufferPtr in
+            publicKey.asMcBuffer { publicKeyBufferPtr in
+                viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+                    subaddressSpendPrivateKey.asMcBuffer { spendPrivateKeyBufferPtr in
+                        var matches = false
+                        // Safety: mc_tx_out_matches_subaddress is infallible when preconditions are
+                        // upheld.
+                        withMcInfallible {
+                            mc_tx_out_matches_subaddress(
+                                targetKeyBufferPtr,
+                                publicKeyBufferPtr,
+                                viewKeyBufferPtr,
+                                spendPrivateKeyBufferPtr,
+                                &matches)
+                        }
+                        return matches
+                    }
+                }
+            }
+        }
+    }
+
+    static func reconstructCommitment(
+        maskedValue: UInt64,
+        publicKey: RistrettoPublic,
+        viewPrivateKey: RistrettoPrivate
+    ) -> Data32? {
+        var mcAmount = McTxOutAmount(masked_value: maskedValue)
+        return publicKey.asMcBuffer { publicKeyBufferPtr in
+            viewPrivateKey.asMcBuffer { viewPrivateKeyPtr in
+                switch Data32.make(withMcMutableBuffer: { bufferPtr, errorPtr in
+                    mc_tx_out_reconstruct_commitment(
+                        &mcAmount,
+                        publicKeyBufferPtr,
+                        viewPrivateKeyPtr,
+                        bufferPtr,
+                        &errorPtr)
+                }) {
+                case .success(let bytes):
+                    // Safety: It's safe to skip validation because
+                    // mc_tx_out_get_subaddress_spend_public_key should always return a valid
+                    // RistrettoPublic on success.
+                    return bytes as Data32
+                case .failure(let error):
+                    switch error.errorCode {
+                    case .invalidInput:
+                        // Safety: This condition indicates a programming error and can only
+                        // happen if arguments to mc_tx_out_get_subaddress_spend_public_key are
+                        // supplied incorrectly.
+                        // FIXME
+                        logger.warning("error: \(redacting: error)")
+                        return nil
+                    default:
+                        // Safety: mc_fog_resolver_add_report_response should not throw
+                        // non-documented errors.
+                        // FIXME
+                        logger.warning("Unhandled LibMobileCoin error: \(redacting: error)")
+                        return nil
+                    }
+                }
+            }
+        }
+    }
+
+    static func subaddressSpentPublicKey(
+        targetKey: RistrettoPublic,
+        publicKey: RistrettoPublic,
+        viewPrivateKey: RistrettoPrivate
+    ) -> RistrettoPublic {
+        targetKey.asMcBuffer { targetKeyBufferPtr in
+            publicKey.asMcBuffer { publicKeyBufferPtr in
+                viewPrivateKey.asMcBuffer { viewPrivateKeyPtr in
+                    switch Data32.make(withMcMutableBuffer: { bufferPtr, errorPtr in
+                        mc_tx_out_get_subaddress_spend_public_key(
+                            targetKeyBufferPtr,
+                            publicKeyBufferPtr,
+                            viewPrivateKeyPtr,
+                            bufferPtr,
+                            &errorPtr)
+                    }) {
+                    case .success(let bytes):
+                        // Safety: It's safe to skip validation because
+                        // mc_tx_out_get_subaddress_spend_public_key should always return a valid
+                        // RistrettoPublic on success.
+                        return RistrettoPublic(skippingValidation: bytes)
+                    case .failure(let error):
+                        switch error.errorCode {
+                        case .invalidInput:
+                            // Safety: This condition indicates a programming error and can only
+                            // happen if arguments to mc_tx_out_get_subaddress_spend_public_key are
+                            // supplied incorrectly.
+                            logger.fatalError("error: \(redacting: error)")
+                        default:
+                            // Safety: mc_fog_resolver_add_report_response should not throw
+                            // non-documented errors.
+                            logger.fatalError("Unhandled LibMobileCoin error: \(redacting: error)")
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    /// - Returns: `nil` when `viewPrivateKey` cannot unmask value, either because `viewPrivateKey`
+    ///     does not own `TxOut` or because `TxOut` values are incongruent.
+    static func value(
+        maskedValue: UInt64,
+        publicKey: RistrettoPublic,
+        viewPrivateKey: RistrettoPrivate
+    ) -> UInt64? {
+        var mcAmount = McTxOutAmount(masked_value: maskedValue)
+        return publicKey.asMcBuffer { publicKeyPtr in
+            viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+                var valueOut: UInt64 = 0
+                switch withMcError({ errorPtr in
+                    mc_tx_out_get_value(
+                        &mcAmount,
+                        publicKeyPtr,
+                        viewKeyBufferPtr,
+                        &valueOut,
+                        &errorPtr)
+                }) {
+                case .success:
+                    return valueOut
+                case .failure(let error):
+                    switch error.errorCode {
+                    case .transactionCrypto:
+                        // Indicates either `commitment`/`maskedValue`/`publicKey` values are
+                        // incongruent or `viewPrivateKey` does not own `TxOut`. However, it's
+                        // not possible to determine which, only that the provided `commitment`
+                        // doesn't match the computed commitment.
+                        return nil
+                    case .invalidInput:
+                        // Safety: This condition indicates a programming error and can only
+                        // happen if arguments to mc_tx_out_get_value are supplied incorrectly.
+                        logger.fatalError("error: \(redacting: error)")
+                    default:
+                        // Safety: mc_tx_out_get_value should not throw non-documented errors.
+                        logger.fatalError("Unhandled LibMobileCoin error: \(redacting: error)")
+                    }
+                }
+            }
+        }
+    }
+
+    /// - Returns: `nil` when a valid `KeyImage` cannot be constructed, either because
+    ///     `viewPrivateKey`/`subaddressSpendPrivateKey` do not own `TxOut` or because `TxOut`
+    ///     values are incongruent.
+    static func keyImage(
+        targetKey: RistrettoPublic,
+        publicKey: RistrettoPublic,
+        viewPrivateKey: RistrettoPrivate,
+        subaddressSpendPrivateKey: RistrettoPrivate
+    ) -> KeyImage? {
+        targetKey.asMcBuffer { targetKeyPtr in
+            publicKey.asMcBuffer { publicKeyPtr in
+                viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+                    subaddressSpendPrivateKey.asMcBuffer { spendKeyBufferPtr in
+                        switch Data32.make(withMcMutableBuffer: { bufferPtr, errorPtr in
+                            mc_tx_out_get_key_image(
+                                targetKeyPtr,
+                                publicKeyPtr,
+                                viewKeyBufferPtr,
+                                spendKeyBufferPtr,
+                                bufferPtr,
+                                &errorPtr)
+                        }) {
+                        case .success(let keyImageData):
+                            return KeyImage(keyImageData)
+                        case .failure(let error):
+                            switch  error.errorCode {
+                            case .transactionCrypto:
+                                // Indicates either `targetKey`/`publicKey` values are incongruent
+                                //  or`viewPrivateKey`/`subaddressSpendPrivateKey` does not own
+                                // `TxOut`. However, it's not possible to determine which, only that
+                                // the provided `targetKey` doesn't match the computed target key
+                                // (aka onetime public key).
+                                return nil
+                            case .invalidInput:
+                                // Safety: This condition indicates a programming error and can only
+                                // happen if arguments to mc_tx_out_get_key_image are supplied
+                                // incorrectly.
+                                logger.fatalError("error: \(redacting: error)")
+                            default:
+                                // Safety: mc_tx_out_get_key_image should not throw non-documented
+                                // errors.
+                                logger.fatalError(
+                                    "Unhandled LibMobileCoin error: \(redacting: error)")
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+
+    static func validateConfirmationNumber(
+        publicKey: RistrettoPublic,
+        confirmationNumber: TxOutConfirmationNumber,
+        viewPrivateKey: RistrettoPrivate
+    ) -> Bool {
+        publicKey.asMcBuffer { publicKeyPtr in
+            confirmationNumber.asMcBuffer { confirmationNumberPtr in
+                viewPrivateKey.asMcBuffer { viewKeyBufferPtr in
+                    var result = false
+                    // Safety: mc_tx_out_validate_confirmation_number is infallible when
+                    // preconditions are upheld.
+                    withMcInfallible {
+                        mc_tx_out_validate_confirmation_number(
+                            publicKeyPtr,
+                            confirmationNumberPtr,
+                            viewKeyBufferPtr,
+                            &result)
+                    }
+                    return result
+                }
+            }
+        }
+    }
+}
--- a/Sources/LibMobileCoin/CStructWrapper.swift
+++ b/Sources/LibMobileCoin/CStructWrapper.swift
@ -0,0 +1,27 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+protocol CStructWrapper {
+    associatedtype CStruct
+
+    func withUnsafeCStructPointer<R>(
+        _ body: (UnsafePointer<CStruct>) throws -> R
+    ) rethrows -> R
+}
+
+extension Optional where Wrapped: CStructWrapper {
+    func withUnsafeCStructPointer<R>(
+        _ body: (UnsafePointer<Wrapped.CStruct>?) throws -> R
+    ) rethrows -> R {
+        if let unwrapped = self {
+            return try unwrapped.withUnsafeCStructPointer { ptr in
+                try body(ptr)
+            }
+        } else {
+            return try body(nil)
+        }
+    }
+}
--- a/Sources/LibMobileCoin/Data+withMcMutableBuffer.swift
+++ b/Sources/LibMobileCoin/Data+withMcMutableBuffer.swift
@ -0,0 +1,125 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable colon multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+extension Data {
+    static func make(
+        withMcMutableBuffer body:
+            (UnsafeMutablePointer<McMutableBuffer>?, inout UnsafeMutablePointer<McError>?) -> Int
+    ) -> Result<Data, LibMobileCoinError> {
+        withMcErrorReturningArrayCount { errorPtr in
+            // Call body() with nil to get number of bytes.
+            body(nil, &errorPtr)
+        }.flatMap { numBytes in
+            // Call body() again with a pointer to the output buffer.
+            var bytes = Data(repeating: 0, count: numBytes)
+            return bytes.asMcMutableBuffer { bufferPtr in
+                withMcErrorReturningArrayCount { errorPtr in
+                    body(bufferPtr, &errorPtr)
+                }
+            }.map { numBytesWritten in
+                guard numBytesWritten <= numBytes else {
+                    // This condition indicates a programming error.
+                    logger.fatalError(
+                        "numBytesWritten (\(numBytesWritten)) must be <= numBytes (\(numBytes))")
+                }
+
+                return bytes.prefix(numBytesWritten)
+            }
+        }
+    }
+
+    static func make(
+        withFixedLengthMcMutableBuffer numBytes: Int,
+        body: (UnsafeMutablePointer<McMutableBuffer>, inout UnsafeMutablePointer<McError>?) -> Bool
+    ) -> Result<Data, LibMobileCoinError> {
+        var bytes = Data(repeating: 0, count: numBytes)
+        return bytes.asMcMutableBuffer { bufferPtr in
+            withMcError { errorPtr in
+                body(bufferPtr, &errorPtr)
+            }
+        }.map { bytes }
+    }
+
+    static func make(
+        withEstimatedLengthMcMutableBuffer numBytes: Int,
+        body: (UnsafeMutablePointer<McMutableBuffer>, inout UnsafeMutablePointer<McError>?) -> Int
+    ) -> Result<Data, LibMobileCoinError> {
+        var bytes = Data(repeating: 0, count: numBytes)
+        return bytes.asMcMutableBuffer { bufferPtr in
+            withMcErrorReturningArrayCount { errorPtr in
+                body(bufferPtr, &errorPtr)
+            }
+        }.map { numBytesReturned in
+            guard numBytesReturned <= numBytes else {
+                // This condition indicates a programming error.
+                logger.fatalError(
+                    "Number of bytes returned from LibMobileCoin (\(numBytesReturned)) is " +
+                        "greater than estimated (\(numBytes))")
+            }
+
+            return bytes.prefix(numBytesReturned)
+        }
+    }
+
+    init(
+        withFixedLengthMcMutableBufferInfallible numBytes: Int,
+        body: (UnsafeMutablePointer<McMutableBuffer>) -> Bool
+    ) {
+        self.init(repeating: 0, count: numBytes)
+        let success = asMcMutableBuffer { bufferPtr in
+            body(bufferPtr)
+        }
+        guard success else {
+            // This condition indicates a programming error.
+            logger.fatalError("Infallible LibMobileCoin function failed.")
+        }
+    }
+
+    init(withMcMutableBufferInfallible body: (UnsafeMutablePointer<McMutableBuffer>?) -> Int) {
+        // Call body() with nil to get number of bytes.
+        let numBytes = body(nil)
+        guard numBytes >= 0 else {
+            // This condition indicates a programming error.
+            logger.fatalError("Infallible LibMobileCoin function failed.")
+        }
+
+        var bytes = Data(repeating: 0, count: numBytes)
+        let numBytesWritten = bytes.asMcMutableBuffer { bufferPtr in
+            body(bufferPtr)
+        }
+        guard numBytesWritten >= 0 else {
+            // This condition indicates a programming error.
+            logger.fatalError("Infallible LibMobileCoin function failed.")
+        }
+
+        guard numBytesWritten <= numBytes else {
+            // This condition indicates a programming error.
+            logger.fatalError(
+                "numBytesWritten (\(numBytesWritten)) must be <= numBytes (\(numBytes))")
+        }
+
+        self = bytes.prefix(numBytesWritten)
+    }
+
+    init(
+        withEstimatedLengthMcMutableBufferInfallible numBytes: Int,
+        body: (UnsafeMutablePointer<McMutableBuffer>) -> Int
+    ) {
+        var bytes = Data(repeating: 0, count: numBytes)
+        let numBytesReturned = bytes.asMcMutableBuffer(body)
+        guard numBytesReturned <= numBytes else {
+            // This condition indicates a programming error.
+            logger.fatalError(
+                "Number of bytes returned from LibMobileCoin \(numBytesReturned) is greater than " +
+                    "estimated \(numBytes)")
+        }
+
+        self = bytes.prefix(numBytesReturned)
+    }
+}
--- a/Sources/LibMobileCoin/Data32+withMcMutableBuffer.swift
+++ b/Sources/LibMobileCoin/Data32+withMcMutableBuffer.swift
@ -0,0 +1,69 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable colon multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+extension Data32 {
+    static func make(
+        withMcMutableBuffer body:
+            (UnsafeMutablePointer<McMutableBuffer>, inout UnsafeMutablePointer<McError>?) -> Bool
+    ) -> Result<Data32, LibMobileCoinError> {
+        var bytes = Data32()
+        return bytes.asMcMutableBuffer { bufferPtr in
+            withMcError { errorPtr in
+                body(bufferPtr, &errorPtr)
+            }
+        }.map { bytes }
+    }
+
+    static func make(
+        withMcMutableBuffer body:
+            (UnsafeMutablePointer<McMutableBuffer>, inout UnsafeMutablePointer<McError>?) -> Int
+    ) -> Result<Data32, LibMobileCoinError> {
+        var bytes = Data32()
+        return bytes.asMcMutableBuffer { bufferPtr in
+            withMcErrorReturningArrayCount { errorPtr in
+                body(bufferPtr, &errorPtr)
+            }
+        }.map { numBytesReturned in
+            guard numBytesReturned == 32 else {
+                // This condition indicates a programming error.
+                logger.fatalError(
+                    "LibMobileCoin function returned unexpected byte count " +
+                        "(\(numBytesReturned)). Expected 32.")
+            }
+            return bytes
+        }
+    }
+
+    init(withMcMutableBufferInfallible body: (UnsafeMutablePointer<McMutableBuffer>) -> Bool) {
+        self.init()
+        asMcMutableBuffer { bufferPtr in
+            guard body(bufferPtr) else {
+                // This condition indicates a programming error.
+                logger.fatalError("Infallible LibMobileCoin function failed.")
+            }
+        }
+    }
+
+    init(withMcMutableBufferInfallible body: (UnsafeMutablePointer<McMutableBuffer>) -> Int) {
+        self.init()
+        let numBytesReturned = asMcMutableBuffer { bufferPtr in
+            body(bufferPtr)
+        }
+        guard numBytesReturned > 0 else {
+            // This condition indicates a programming error.
+            logger.fatalError("Infallible LibMobileCoin function failed.")
+        }
+        guard numBytesReturned == 32 else {
+            // This condition indicates a programming error.
+            logger.fatalError(
+                "LibMobileCoin function returned unexpected byte count (\(numBytesReturned)). " +
+                    "Expected 32.")
+        }
+    }
+}
--- a/Sources/LibMobileCoin/LibMobileCoinError.swift
+++ b/Sources/LibMobileCoin/LibMobileCoinError.swift
@ -0,0 +1,35 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+struct LibMobileCoinError: Error {
+    static func make(consuming error: UnsafeMutablePointer<McError>)
+        -> Result<LibMobileCoinError, InvalidInputError>
+    {
+        defer {
+            mc_error_free(error)
+        }
+        guard let libMcError = LibMobileCoinError(error.pointee) else {
+            return .failure(InvalidInputError(
+                "Unknown LibMobileCoin error code: \(error.pointee.error_code), description: " +
+                "\(String(cString: error.pointee.error_description))"))
+        }
+        return .success(libMcError)
+    }
+
+    let errorCode: McErrorCode
+    let description: String
+
+    /// - Returns: `nil` when the error kind is unrecognized.
+    init?(_ error: McError) {
+        self.description = String(cString: error.error_description)
+
+        guard let errorCode = McErrorCode(rawValue: error.error_code) else {
+            return nil
+        }
+        self.errorCode = errorCode
+    }
+}
--- a/Sources/LibMobileCoin/McConstants.swift
+++ b/Sources/LibMobileCoin/McConstants.swift
@ -0,0 +1,204 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+enum McConstants {}
+
+// MARK: - Transaction
+
+extension McConstants {
+
+    /// Each input ring must contain this many elements.
+    static let RING_SIZE = 11
+
+    /// Each transaction must contain no more than this many inputs (rings).
+    static let MAX_INPUTS = 16
+
+    /// Each transaction must contain no more than this many outputs.
+    static let MAX_OUTPUTS = 16
+
+    /// Maximum number of blocks in the future a transaction's tombstone block can be set to.
+    static let MAX_TOMBSTONE_BLOCKS: UInt64 = 100
+
+    /// Minimum allowed fee, denominated in picoMOB.
+    static let DEFAULT_MINIMUM_FEE: UInt64 = 10_000_000_000
+
+    /// Transaction hash length, in bytes.
+    static let TX_HASH_LEN = 32
+
+    /// Length of a Transaction's encrypted fog hint field, in bytes.
+    static let ENCRYPTED_FOG_HINT_LEN = 128
+
+    /// Length of a Transaction confirmation number, in bytes.
+    static let CONFIRMATION_NUMBER_LEN = 32
+
+}
+
+// MARK: - Block
+
+extension McConstants {
+
+    /// Maximum number of transactions that may be included in a Block.
+    static let MAX_TRANSACTIONS_PER_BLOCK = 5000
+
+}
+
+// MARK: - TxOut
+
+extension McConstants {
+
+    /// Length of a TxOut key image, in bytes.
+    static let KEY_IMAGE_LEN = 32
+
+}
+
+// MARK: - MOB
+
+extension McConstants {
+
+    /// The MobileCoin network will contain a fixed supply of 250 million mobilecoins (MOB).
+    static let TOTAL_MOB: UInt64 = 250_000_000
+
+}
+
+// MARK: - Account key
+
+extension McConstants {
+
+    /// Length of the root entropy used to construct an account key, in bytes.
+    static let ROOT_ENTROPY_LEN = 32
+
+    /// An account's "default address" is its zero^th subaddress.
+    static let DEFAULT_SUBADDRESS_INDEX: UInt64 = 0
+
+}
+
+// MARK: - Keys
+
+extension McConstants {
+
+    /// Ristretto private key length, in bytes.
+    static let RISTRETTO_PRIVATE_LEN = 32
+
+    /// Ristretto public key length, in bytes.
+    static let RISTRETTO_PUBLIC_LEN = 32
+
+    /// The length of a curve25519 EdDSA `Signature`, in bytes.
+    static let SCHNORRKEL_SIGNATURE_LEN = 64
+
+}
+
+// MARK: - Attestation
+
+extension McConstants {
+
+    /// MRENCLAVE length, in bytes.
+    static let MRENCLAVE_LEN = 32
+
+    /// MRSIGNER length, in bytes.
+    static let MRSIGNER_LEN = 32
+
+}
+
+// MARK: - Enclave
+
+extension McConstants {
+
+    static let CONSENSUS_PRODUCT_ID: UInt16 = 1
+    static let FOG_VIEW_PRODUCT_ID: UInt16 = 3
+    static let FOG_LEDGER_PRODUCT_ID: UInt16 = 2
+    static let FOG_REPORT_PRODUCT_ID: UInt16 = 4
+
+    static let CONSENSUS_SECURITY_VERSION: UInt16 = 1
+    static let DEV_CONSENSUS_MRSIGNER_HEX =
+        "7ee5e29d74623fdbc6fbf1454be6f3bb0b86c12366b7b478ad13353e44de8411"
+    static let DEV_CONSENSUS_MRSIGNER = Data([
+        126, 229, 226, 157, 116, 98, 63, 219, 198, 251, 241, 69, 75, 230, 243, 187, 11, 134, 193,
+        35, 102, 183, 180, 120, 173, 19, 53, 62, 68, 222, 132, 17,
+    ])
+    static let TESTNET_CONSENSUS_MRSIGNER_HEX =
+        "bf7fa957a6a94acb588851bc8767e0ca57706c79f4fc2aa6bcb993012c3c386c"
+    static let TESTNET_CONSENSUS_MRSIGNER = Data([
+        191, 127, 169, 87, 166, 169, 74, 203, 88, 136, 81, 188, 135, 103, 224, 202, 87, 112, 108,
+        121, 244, 252, 42, 166, 188, 185, 147, 1, 44, 60, 56, 108,
+    ])
+
+    static let FOG_VIEW_SECURITY_VERSION: UInt16 = 1
+    static let FOG_LEDGER_SECURITY_VERSION: UInt16 = 1
+    static let DEV_FOG_MRSIGNER_HEX =
+        "7ee5e29d74623fdbc6fbf1454be6f3bb0b86c12366b7b478ad13353e44de8411"
+    static let DEV_FOG_MRSIGNER = Data([
+        126, 229, 226, 157, 116, 98, 63, 219, 198, 251, 241, 69, 75, 230, 243, 187, 11, 134, 193,
+        35, 102, 183, 180, 120, 173, 19, 53, 62, 68, 222, 132, 17,
+    ])
+    static let TESTNET_FOG_MRSIGNER_HEX =
+        "bf7fa957a6a94acb588851bc8767e0ca57706c79f4fc2aa6bcb993012c3c386c"
+    static let TESTNET_FOG_MRSIGNER = Data([
+        191, 127, 169, 87, 166, 169, 74, 203, 88, 136, 81, 188, 135, 103, 224, 202, 87, 112, 108,
+        121, 244, 252, 42, 166, 188, 185, 147, 1, 44, 60, 56, 108,
+    ])
+
+    static let FOG_REPORT_SECURITY_VERSION: UInt16 = 1
+    static let DEV_FOG_REPORT_MRSIGNER_HEX =
+        "7ee5e29d74623fdbc6fbf1454be6f3bb0b86c12366b7b478ad13353e44de8411"
+    static let DEV_FOG_REPORT_MRSIGNER = Data([
+        126, 229, 226, 157, 116, 98, 63, 219, 198, 251, 241, 69, 75, 230, 243, 187, 11, 134, 193,
+        35, 102, 183, 180, 120, 173, 19, 53, 62, 68, 222, 132, 17,
+    ])
+    static let TESTNET_FOG_REPORT_MRSIGNER_HEX =
+        "bf7fa957a6a94acb588851bc8767e0ca57706c79f4fc2aa6bcb993012c3c386c"
+    static let TESTNET_FOG_REPORT_MRSIGNER = Data([
+        191, 127, 169, 87, 166, 169, 74, 203, 88, 136, 81, 188, 135, 103, 224, 202, 87, 112, 108,
+        121, 244, 252, 42, 166, 188, 185, 147, 1, 44, 60, 56, 108,
+    ])
+
+}
+
+// MARK: - Url
+
+extension McConstants {
+
+    static let MOB_URI_SCHEME = "mob"
+
+    /// The part before the '://' of a URL.
+    static let CONSENSUS_SCHEME_SECURE = "mc"
+    static let CONSENSUS_SCHEME_INSECURE = "insecure-mc"
+
+    /// Default port numbers
+    static let CONSENSUS_DEFAULT_SECURE_PORT = 443
+    static let CONSENSUS_DEFAULT_INSECURE_PORT = 3223
+
+    /// The part before the '://' of a URL.
+    static let FOG_SCHEME_SECURE = "fog"
+    static let FOG_SCHEME_INSECURE = "insecure-fog"
+
+    /// Default port numbers
+    static let FOG_DEFAULT_SECURE_PORT = 443
+    static let FOG_DEFAULT_INSECURE_PORT = 3225
+
+}
+
+// MARK: - Fog Report
+
+extension McConstants {
+
+    /// Fog authority subjectPublicKeyInfo used in development, in hexidecimal.
+    static let DEV_FOG_AUTHORITY_SPKI_HEX = "23e9dfabdaf74c69428ec0dfac15784eedc7466e"
+    /// Fog authority subjectPublicKeyInfo used in development, in bytes.
+    static let DEV_FOG_AUTHORITY_SPKI = Data([
+        35, 233, 223, 171, 218, 247, 76, 105, 66, 142, 192, 223, 172, 21, 120, 78, 237, 199, 70,
+        110,
+    ])
+
+}
+
+// MARK: - Fog Ledger
+
+extension McConstants {
+
+    /// Maximum number of Key Images that may be checked in a single request.
+    static let FOG_KEY_IMAGE_MAX_REQUEST_SIZE = 2000
+
+}
--- a/Sources/LibMobileCoin/McData.swift
+++ b/Sources/LibMobileCoin/McData.swift
@ -0,0 +1,35 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+final class McData {
+    let ptr: OpaquePointer
+
+    init(_ ptr: OpaquePointer) {
+        self.ptr = ptr
+    }
+
+    deinit {
+        mc_data_free(ptr)
+    }
+
+    var bytes: Data {
+        Data(withMcMutableBufferInfallible: { bufferPtr in
+            mc_data_get_bytes(ptr, bufferPtr)
+        })
+    }
+}
+
+extension Data {
+    static func make(withMcDataBytes body: (inout UnsafeMutablePointer<McError>?) -> OpaquePointer?)
+        -> Result<Data, LibMobileCoinError>
+    {
+        withMcError(body).map {
+            let mcData = McData($0)
+            return mcData.bytes
+        }
+    }
+}
--- a/Sources/LibMobileCoin/McError.swift
+++ b/Sources/LibMobileCoin/McError.swift
@ -0,0 +1,119 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+func withMcInfallible(_ body: () -> OpaquePointer?) -> OpaquePointer {
+    guard let value = body() else {
+        logger.fatalError("Error: \(#function): Infallible LibMobileCoin function failed")
+    }
+    return value
+}
+
+func withMcError(_ body: (inout UnsafeMutablePointer<McError>?) -> OpaquePointer?)
+    -> Result<OpaquePointer, LibMobileCoinError>
+{
+    var error: UnsafeMutablePointer<McError>?
+    guard let value = body(&error) else {
+        guard let mcError = error else {
+            // Safety: This condition should never occur and indicates a programming error.
+            logger.fatalError("Error: \(#function): block returned failure but out_error == NULL.")
+        }
+        let err: LibMobileCoinError
+        do {
+            err = try LibMobileCoinError.make(consuming: mcError).get()
+        } catch {
+            logger.fatalError("Error: \(#function): \(error)")
+        }
+        guard err.errorCode != .panic else {
+            logger.fatalError("LibMobileCoin function panicked: \(redacting: err.description)")
+        }
+        return .failure(err)
+    }
+    return .success(value)
+}
+
+func withMcInfallible(_ body: () -> Bool) {
+    guard body() else {
+        logger.fatalError("Error: \(#function): Infallible LibMobileCoin function failed.")
+    }
+}
+
+func withMcError(_ body: (inout UnsafeMutablePointer<McError>?) -> Bool)
+    -> Result<(), LibMobileCoinError>
+{
+    var error: UnsafeMutablePointer<McError>?
+    guard body(&error) else {
+        guard let mcError = error else {
+            // Safety: This condition should never occur and indicates a programming error.
+            logger.fatalError("Error: \(#function): block returned failure but out_error == NULL.")
+        }
+        let err: LibMobileCoinError
+        do {
+            err = try LibMobileCoinError.make(consuming: mcError).get()
+        } catch {
+            logger.fatalError("Error: \(#function): \(error)")
+        }
+        guard err.errorCode != .panic else {
+            logger.fatalError("LibMobileCoin function panicked: \(redacting: err.description)")
+        }
+        return .failure(err)
+    }
+    return .success(())
+}
+
+func withMcInfallibleReturningOptional<T>(_ body: () -> T?) -> T {
+    guard let value = body() else {
+        logger.fatalError("Error: \(#function): Infallible LibMobileCoin function failed.")
+    }
+    return value
+}
+
+func withMcErrorReturningOptional<T>(_ body: (inout UnsafeMutablePointer<McError>?) -> T?)
+    -> Result<T, LibMobileCoinError>
+{
+    var error: UnsafeMutablePointer<McError>?
+    guard let value = body(&error) else {
+        guard let mcError = error else {
+            // Safety: This condition should never occur and indicates a programming error.
+            logger.fatalError("Error: \(#function): block returned failure but out_error == NULL.")
+        }
+        let err: LibMobileCoinError
+        do {
+            err = try LibMobileCoinError.make(consuming: mcError).get()
+        } catch {
+            logger.fatalError("Error: \(#function): \(error)")
+        }
+        guard err.errorCode != .panic else {
+            logger.fatalError("LibMobileCoin function panicked: \(redacting: err.description)")
+        }
+        return .failure(err)
+    }
+    return .success(value)
+}
+
+func withMcErrorReturningArrayCount(_ body: (inout UnsafeMutablePointer<McError>?) -> Int)
+    -> Result<Int, LibMobileCoinError>
+{
+    var error: UnsafeMutablePointer<McError>?
+    let value = body(&error)
+    guard value >= 0 else {
+        guard let mcError = error else {
+            // Safety: This condition should never occur and indicates a programming error.
+            logger.fatalError("Error: \(#function): block returned failure but out_error == NULL.")
+        }
+        let err: LibMobileCoinError
+        do {
+            err = try LibMobileCoinError.make(consuming: mcError).get()
+        } catch {
+            logger.fatalError("Error: \(#function): \(error)")
+        }
+        guard err.errorCode != .panic else {
+            logger.fatalError("LibMobileCoin function panicked: \(redacting: err.description)")
+        }
+        return .failure(err)
+    }
+    return .success(value)
+}
--- a/Sources/LibMobileCoin/McRngCallback.swift
+++ b/Sources/LibMobileCoin/McRngCallback.swift
@ -0,0 +1,22 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+func withMcRngCallback<T>(
+    rng: (@convention(c) (UnsafeMutableRawPointer?) -> UInt64)?,
+    rngContext: Any?,
+    _ body: (UnsafeMutablePointer<McRngCallback>?) throws -> T
+) rethrows -> T {
+    if let rng = rng {
+        var rngContext = rngContext
+        return try withUnsafeMutablePointer(to: &rngContext) { rngContextPtr in
+            var rngCallback = McRngCallback(rng: rng, context: rngContextPtr)
+            return try body(&rngCallback)
+        }
+    } else {
+        return try body(nil)
+    }
+}
--- a/Sources/LibMobileCoin/McString.swift
+++ b/Sources/LibMobileCoin/McString.swift
@ -0,0 +1,17 @@
+// swiftlint:disable:this file_name
+
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+extension String {
+    init(mcString: UnsafeMutablePointer<CChar>) {
+        defer {
+            mc_string_free(mcString)
+        }
+        self.init(cString: mcString)
+    }
+}
--- a/Sources/LibMobileCoin/MobileCoinUpstreamInterop.swift
+++ b/Sources/LibMobileCoin/MobileCoinUpstreamInterop.swift
@ -0,0 +1,11 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable orphaned_doc_comment
+
+import LibMobileCoin
+
+/// This file contains temporary interop code to allow easy source compatibility with upstream
+/// LibMobileCoin and MobileCoin server code. The code in this file can be removed once upstream
+/// is deployed to alpha and the older server code no longer needs to be supported.
--- a/Sources/LibMobileCoin/ProtoExtensions.swift
+++ b/Sources/LibMobileCoin/ProtoExtensions.swift
@ -0,0 +1,183 @@
+// swiftlint:disable:this file_name
+
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+// MARK: - External
+
+extension External_RistrettoPrivate {
+    init<DataType: DataConvertible>(_ data: DataType) {
+        self.init()
+        self.data = data.data
+    }
+}
+
+extension External_CompressedRistretto {
+    init<DataType: DataConvertible>(_ data: DataType) {
+        self.init()
+        self.data = data.data
+    }
+}
+
+extension External_KeyImage {
+    init<DataType: DataConvertible>(_ data: DataType) {
+        self.init()
+        self.data = data.data
+    }
+}
+
+extension External_Amount {
+    init<CommitmentType: DataConvertible>(commitment: CommitmentType, maskedValue: UInt64) {
+        self.init()
+        self.commitment = External_CompressedRistretto(commitment)
+        self.maskedValue = maskedValue
+    }
+}
+
+extension External_EncryptedFogHint {
+    init<DataType: DataConvertible>(_ data: DataType) {
+        self.init()
+        self.data = data.data
+    }
+}
+
+// MARK: - Fog Common
+
+extension FogCommon_BlockRange {
+    init(_ range: Range<UInt64>) {
+        self.init()
+        self.startBlock = range.lowerBound
+        self.endBlock = range.upperBound
+    }
+
+    var range: Range<UInt64> {
+        get { startBlock..<endBlock }
+        set {
+            startBlock = newValue.lowerBound
+            endBlock = newValue.upperBound
+        }
+    }
+}
+
+// MARK: - Fog View
+
+extension FogView_RngRecord {
+    init(nonce fogRngKey: FogRngKey, startBlock: UInt64) {
+        self.init()
+        self.pubkey = KexRng_KexRngPubkey(fogRngKey)
+        self.startBlock = startBlock
+    }
+}
+
+extension FogView_TxOutSearchResult {
+    var resultCodeEnum: FogView_TxOutSearchResultCode {
+        get {
+            FogView_TxOutSearchResultCode(rawValue: Int(resultCode))
+                ?? .UNRECOGNIZED(Int(resultCode))
+        }
+        set { resultCode = UInt32(newValue.rawValue) }
+    }
+}
+
+extension FogView_TxOutRecord {
+    var timestampDate: Date? {
+        get { timestamp != UInt64.max ? Date(timeIntervalSince1970: TimeInterval(timestamp)) : nil }
+        set {
+            if let newValue = newValue {
+                timestamp = UInt64(newValue.timeIntervalSince1970)
+            } else {
+                timestamp = UInt64.max
+            }
+        }
+    }
+}
+
+// MARK: - Fog Ledger
+
+extension FogLedger_OutputResult {
+    var resultCodeEnum: FogLedger_OutputResultCode {
+        get {
+            FogLedger_OutputResultCode(rawValue: Int(resultCode)) ?? .UNRECOGNIZED(Int(resultCode))
+        }
+        set { resultCode = UInt32(newValue.rawValue) }
+    }
+}
+
+extension FogLedger_KeyImageResult {
+    var timestampDate: Date {
+        get { Date(timeIntervalSince1970: TimeInterval(timestamp)) }
+        set { timestamp = UInt64(newValue.timeIntervalSince1970) }
+    }
+
+    var timestampResultCodeEnum: Watcher_TimestampResultCode {
+        get {
+            Watcher_TimestampResultCode(rawValue: Int(timestampResultCode))
+                ?? .UNRECOGNIZED(Int(timestampResultCode))
+        }
+        set { timestampResultCode = UInt32(newValue.rawValue) }
+    }
+
+    var keyImageResultCodeEnum: FogLedger_KeyImageResultCode {
+        get {
+            FogLedger_KeyImageResultCode(rawValue: Int(keyImageResultCode))
+                ?? .UNRECOGNIZED(Int(keyImageResultCode))
+        }
+        set { keyImageResultCode = UInt32(newValue.rawValue) }
+    }
+
+    var timestampStatus: BlockMetadata.TimestampStatus? {
+        switch timestampResultCodeEnum {
+        case .timestampFound:
+            return .known(timestamp: timestampDate)
+        case .unavailable:
+            return .unavailable
+        case .watcherBehind, .watcherDatabaseError, .blockIndexOutOfBounds:
+            return .temporarilyUnknown
+        case .unusedField, .UNRECOGNIZED:
+            return nil
+        }
+    }
+}
+
+extension FogLedger_BlockRequest {
+    var rangeValues: [Range<UInt64>] {
+        get { ranges.map { $0.startBlock..<$0.endBlock } }
+        set { ranges = newValue.map { FogCommon_BlockRange($0) } }
+    }
+}
+
+extension FogLedger_BlockData {
+    var timestampDate: Date {
+        get { Date(timeIntervalSince1970: TimeInterval(timestamp)) }
+        set { timestamp = UInt64(newValue.timeIntervalSince1970) }
+    }
+
+    var timestampResultCodeEnum: Watcher_TimestampResultCode {
+        get {
+            Watcher_TimestampResultCode(rawValue: Int(timestampResultCode))
+                ?? .UNRECOGNIZED(Int(timestampResultCode))
+        }
+        set { timestampResultCode = UInt32(newValue.rawValue) }
+    }
+
+    var timestampStatus: BlockMetadata.TimestampStatus? {
+        switch timestampResultCodeEnum {
+        case .timestampFound:
+            return .known(timestamp: timestampDate)
+        case .unavailable:
+            return .unavailable
+        case .watcherBehind, .watcherDatabaseError, .blockIndexOutOfBounds:
+            return .temporarilyUnknown
+        case .unusedField, .UNRECOGNIZED:
+            return nil
+        }
+    }
+
+    var metadata: BlockMetadata {
+        BlockMetadata(index: index, timestampStatus: timestampStatus)
+    }
+}
--- a/Sources/LibMobileCoin/ProtoTypes+InfallibleDataSerializable.swift
+++ b/Sources/LibMobileCoin/ProtoTypes+InfallibleDataSerializable.swift
@ -0,0 +1,50 @@
+// swiftlint:disable:this file_name
+
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+// MARK: - External
+
+extension External_AccountKey: InfallibleDataSerializable {}
+
+extension External_PublicAddress: InfallibleDataSerializable {}
+
+extension External_TxOutMembershipProof: InfallibleDataSerializable {}
+
+extension External_TxOut: InfallibleDataSerializable {}
+
+extension External_Tx: InfallibleDataSerializable {}
+
+extension External_Receipt: InfallibleDataSerializable {}
+
+// MARK: - Printable
+
+extension Printable_PrintableWrapper: InfallibleDataSerializable {}
+
+// MARK: - Attest
+
+extension Attest_Message: InfallibleDataSerializable {}
+
+// MARK: - Fog Report
+
+extension Report_ReportResponse: InfallibleDataSerializable {}
+
+// MARK: - Fog View
+
+extension FogView_QueryRequestAAD: InfallibleDataSerializable {}
+extension FogView_QueryRequest: InfallibleDataSerializable {}
+extension FogView_QueryResponse: InfallibleDataSerializable {}
+
+extension FogView_TxOutRecord: InfallibleDataSerializable {}
+
+// MARK: - Fog Ledger
+
+extension FogLedger_GetOutputsRequest: InfallibleDataSerializable {}
+extension FogLedger_GetOutputsResponse: InfallibleDataSerializable {}
+
+extension FogLedger_CheckKeyImagesRequest: InfallibleDataSerializable {}
+extension FogLedger_CheckKeyImagesResponse: InfallibleDataSerializable {}
--- a/Sources/LibMobileCoin/asMcBuffer.swift
+++ b/Sources/LibMobileCoin/asMcBuffer.swift
@ -0,0 +1,50 @@
+// swiftlint:disable:this file_name
+
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+extension DataConvertible {
+    func asMcBuffer<T>(_ body: (UnsafePointer<McBuffer>) throws -> T) rethrows -> T {
+        try data.withUnsafeBytes {
+            let ptr = $0.bindMemory(to: UInt8.self)
+            guard let bufferPtr = ptr.baseAddress else {
+                // This indicates a programming error. Pointer returned from withUnsafeBytes
+                // shouldn't have a nil baseAddress.
+                logger.fatalError("ptr.baseAddress == nil.")
+            }
+            var buffer = McBuffer(buffer: bufferPtr, len: ptr.count)
+            return try body(&buffer)
+        }
+    }
+}
+
+extension MutableData {
+    mutating func asMcMutableBuffer<T>(
+        _ body: (UnsafeMutablePointer<McMutableBuffer>) throws -> T
+    ) rethrows -> T {
+        try withUnsafeMutableBytes {
+            let ptr = $0.bindMemory(to: UInt8.self)
+            guard let bufferPtr = ptr.baseAddress else {
+                // This indicates a programming error. Pointer returned from withUnsafeMutableBytes
+                // shouldn't have a nil baseAddress.
+                logger.fatalError("ptr.baseAddress == nil.")
+            }
+            var buffer = McMutableBuffer(buffer: bufferPtr, len: ptr.count)
+            return try body(&buffer)
+        }
+    }
+}
+
+extension Optional where Wrapped: DataConvertible {
+    func asOptMcBuffer<T>(_ body: (UnsafePointer<McBuffer>?) throws -> T) rethrows -> T {
+        if let unwrapped = self {
+            return try unwrapped.asMcBuffer(body)
+        } else {
+            return try body(nil)
+        }
+    }
+}
--- a/Sources/Mnemonic/AccountKey+Mnemonic.swift
+++ b/Sources/Mnemonic/AccountKey+Mnemonic.swift
@ -0,0 +1,57 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+extension AccountKey {
+    public static func make(
+        entropy: Data,
+        fogReportUrl: String,
+        fogReportId: String,
+        fogAuthoritySpki: Data,
+        accountIndex: UInt32 = 0
+    ) -> Result<AccountKey, InvalidInputError> {
+        Bip39Utils.mnemonic(fromEntropy: entropy).flatMap { mnemonic in
+            make(
+                mnemonic: mnemonic.phrase,
+                fogReportUrl: fogReportUrl,
+                fogReportId: fogReportId,
+                fogAuthoritySpki: fogAuthoritySpki,
+                accountIndex: accountIndex)
+        }
+    }
+
+    public static func make(
+        mnemonic: String,
+        fogReportUrl: String,
+        fogReportId: String,
+        fogAuthoritySpki: Data,
+        accountIndex: UInt32 = 0
+    ) -> Result<AccountKey, InvalidInputError> {
+        Slip10Utils.accountPrivateKeys(fromMnemonic: mnemonic, accountIndex: accountIndex)
+            .flatMap {
+                AccountKey.make(
+                    viewPrivateKey: $0.viewPrivateKey,
+                    spendPrivateKey: $0.spendPrivateKey,
+                    fogReportUrl: fogReportUrl,
+                    fogReportId: fogReportId,
+                    fogAuthoritySpki: fogAuthoritySpki)
+            }
+    }
+
+    init(
+        mnemonic: Mnemonic,
+        fogInfo: FogInfo? = nil,
+        accountIndex: UInt32 = 0,
+        subaddressIndex: UInt64 = McConstants.DEFAULT_SUBADDRESS_INDEX
+    ) {
+        let (viewPrivateKey, spendPrivateKey) =
+            Slip10Utils.accountPrivateKeys(fromMnemonic: mnemonic, accountIndex: accountIndex)
+        self.init(
+            viewPrivateKey: viewPrivateKey,
+            spendPrivateKey: spendPrivateKey,
+            fogInfo: fogInfo,
+            subaddressIndex: subaddressIndex)
+    }
+}
--- a/Sources/Mnemonic/Bip39Utils.swift
+++ b/Sources/Mnemonic/Bip39Utils.swift
@ -0,0 +1,75 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+enum Bip39Utils {
+    static func mnemonic(fromEntropy entropy: Data32) -> Mnemonic {
+        let mnemonic = entropy.asMcBuffer { entropyPtr in
+            String(mcString:
+                withMcInfallibleReturningOptional { mc_bip39_mnemonic_from_entropy(entropyPtr) })
+        }
+        return Mnemonic(phraseSkippingValidation: mnemonic)
+    }
+
+    /// Entropy must be a multiple of 4 bytes and 16-32 bytes in length.
+    static func mnemonic(fromEntropy entropy: Data) -> Result<Mnemonic, InvalidInputError> {
+        guard entropy.count % 4 == 0 else {
+            return .failure(InvalidInputError("BIP39 error: entropy must be a multiple of 4 bytes"))
+        }
+        guard entropy.count >= 16 && entropy.count <= 32 else {
+            return .failure(InvalidInputError(
+                "BIP39 error: entropy must be between 16 and 32 bytes, inclusive"))
+        }
+        let mnemonic = entropy.asMcBuffer { entropyPtr in
+            String(mcString:
+                withMcInfallibleReturningOptional { mc_bip39_mnemonic_from_entropy(entropyPtr) })
+        }
+        return .success(Mnemonic(phraseSkippingValidation: mnemonic))
+    }
+
+    static func words(matchingPrefix prefix: String) -> [String] {
+        let wordsList =
+            String(mcString: withMcInfallibleReturningOptional { mc_bip39_words_by_prefix(prefix) })
+        return wordsList.split(separator: ",").map { String($0) }
+    }
+
+    static func entropy(fromMnemonic mnemonic: Mnemonic) -> Data {
+        switch Data.make(withMcMutableBuffer: { bufferPtr, errorPtr in
+            mc_bip39_entropy_from_mnemonic(mnemonic.phrase, bufferPtr, &errorPtr)
+        }) {
+        case .success(let entropy):
+            return entropy
+        case .failure(let error):
+            switch error.errorCode {
+            case .invalidInput:
+                // Safety: mc_bip39_entropy_from_mnemonic should not return invalidInput as long as
+                // `mnemonic` is well-formed.
+                logger.fatalError(
+                    "BIP39: error deriving entropy from mnemonic: \(redacting: error.description)")
+            default:
+                // Safety: mc_bip39_entropy_from_mnemonic should not throw non-documented errors.
+                logger.fatalError("Unhandled LibMobileCoin error: \(redacting: error)")
+            }
+        }
+    }
+
+    static func entropy(fromMnemonic mnemonic: String) -> Result<Data, InvalidInputError> {
+        Data.make(withMcMutableBuffer: { bufferPtr, errorPtr in
+            mc_bip39_entropy_from_mnemonic(mnemonic, bufferPtr, &errorPtr)
+        }).mapError {
+            switch $0.errorCode {
+            case .invalidInput:
+                return InvalidInputError(
+                    "BIP39: error deriving entropy from mnemonic: \(redacting: $0.description)")
+            default:
+                // Safety: mc_bip39_entropy_from_mnemonic should not throw non-documented errors.
+                logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+            }
+        }
+    }
+}
--- a/Sources/Mnemonic/Mnemonic.swift
+++ b/Sources/Mnemonic/Mnemonic.swift
@ -0,0 +1,28 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+public struct Mnemonic {
+    public static let allWords = Bip39Utils.words(matchingPrefix: "")
+
+    /// Entropy must be a multiple of 4 bytes and 16-32 bytes in length.
+    public static func mnemonic(fromEntropy entropy: Data) -> Result<String, InvalidInputError> {
+        Bip39Utils.mnemonic(fromEntropy: entropy).map { $0.phrase }
+    }
+
+    public static func entropy(fromMnemonic mnemonic: String) -> Result<Data, InvalidInputError> {
+        Bip39Utils.entropy(fromMnemonic: mnemonic)
+    }
+
+    public static func words(matchingPrefix prefix: String) -> [String] {
+        Bip39Utils.words(matchingPrefix: prefix)
+    }
+
+    let phrase: String
+
+    init(phraseSkippingValidation phrase: String) {
+        self.phrase = phrase
+    }
+}
--- a/Sources/Mnemonic/Slip10Utils.swift
+++ b/Sources/Mnemonic/Slip10Utils.swift
@ -0,0 +1,85 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains operator_usage_whitespace
+
+import Foundation
+import LibMobileCoin
+
+/// See https://github.com/satoshilabs/slips/blob/master/slip-0010.md
+enum Slip10Utils {
+    static func accountPrivateKeys(fromMnemonic mnemonic: Mnemonic, accountIndex: UInt32)
+        -> (viewPrivateKey: RistrettoPrivate, spendPrivateKey: RistrettoPrivate)
+    {
+        var viewPrivateKeyOut = Data32()
+        var spendPrivateKeyOut = Data32()
+        viewPrivateKeyOut.asMcMutableBuffer { viewPrivateKeyOutPtr in
+            spendPrivateKeyOut.asMcMutableBuffer { spendPrivateKeyOutPtr in
+                switch withMcError({ errorPtr in
+                    mc_slip10_account_private_keys_from_mnemonic(
+                        mnemonic.phrase,
+                        accountIndex,
+                        viewPrivateKeyOutPtr,
+                        spendPrivateKeyOutPtr,
+                        &errorPtr)
+                }) {
+                case .success:
+                    break
+                case .failure(let error):
+                    switch error.errorCode {
+                    case .invalidInput:
+                        // Safety: mnemonic is guaranteed to satisfy
+                        // mc_slip10_account_private_keys_from_mnemonic preconditions.
+                        logger.fatalError(
+                            "LibMobileCoin invalidInput error: \(redacting: error.description)")
+                    default:
+                        // Safety: mc_slip10_account_private_keys_from_mnemonic should not throw
+                        // non-documented errors.
+                        logger.fatalError("Unhandled LibMobileCoin error: \(redacting: error)")
+                    }
+                }
+            }
+        }
+        // Safety: It's safe to skip validation because
+        // mc_slip10_account_private_keys_from_mnemonic should always return valid
+        // RistrettoPrivate values on success.
+        return (RistrettoPrivate(skippingValidation: viewPrivateKeyOut),
+                RistrettoPrivate(skippingValidation: spendPrivateKeyOut))
+    }
+
+    static func accountPrivateKeys(fromMnemonic mnemonic: String, accountIndex: UInt32)
+        -> Result<(viewPrivateKey: RistrettoPrivate, spendPrivateKey: RistrettoPrivate),
+                  InvalidInputError>
+    {
+        var viewPrivateKeyOut = Data32()
+        var spendPrivateKeyOut = Data32()
+        return viewPrivateKeyOut.asMcMutableBuffer { viewPrivateKeyOutPtr in
+            spendPrivateKeyOut.asMcMutableBuffer { spendPrivateKeyOutPtr in
+                withMcError { errorPtr in
+                    mc_slip10_account_private_keys_from_mnemonic(
+                        mnemonic,
+                        accountIndex,
+                        viewPrivateKeyOutPtr,
+                        spendPrivateKeyOutPtr,
+                        &errorPtr)
+                }.mapError {
+                    switch $0.errorCode {
+                    case .invalidInput:
+                        return InvalidInputError("\(redacting: $0.description)")
+                    default:
+                        // Safety: mc_slip10_account_private_keys_from_mnemonic should not throw
+                        // non-documented errors.
+                        logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+                    }
+                }
+            }
+        }.map {
+            // Safety: It's safe to skip validation because
+            // mc_slip10_account_private_keys_from_mnemonic should always return valid
+            // RistrettoPrivate values on success.
+            return (RistrettoPrivate(skippingValidation: viewPrivateKeyOut),
+                    RistrettoPrivate(skippingValidation: spendPrivateKeyOut))
+        }
+    }
+}
--- a/Sources/MobileCoinClient.swift
+++ b/Sources/MobileCoinClient.swift
@ -0,0 +1,401 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable function_parameter_count multiline_arguments multiline_function_chains
+
+import Foundation
+import NIOSSL
+
+public final class MobileCoinClient {
+    /// - Returns: `InvalidInputError` when `accountKey` isn't configured to use Fog.
+    public static func make(accountKey: AccountKey, config: Config)
+        -> Result<MobileCoinClient, InvalidInputError>
+    {
+        guard let accountKey = AccountKeyWithFog(accountKey: accountKey) else {
+            let errorMessage = "Accounts without fog URLs are not currently supported."
+            logger.error(errorMessage, logFunction: false)
+            return .failure(InvalidInputError(errorMessage))
+        }
+
+        return .success(MobileCoinClient(accountKey: accountKey, config: config))
+    }
+
+    private let accountLock: ReadWriteDispatchLock<Account>
+    private let serialQueue: DispatchQueue
+    private let callbackQueue: DispatchQueue
+
+    private let txOutSelectionStrategy: TxOutSelectionStrategy
+    private let mixinSelectionStrategy: MixinSelectionStrategy
+    private let fogQueryScalingStrategy: FogQueryScalingStrategy
+
+    private let serviceProvider: ServiceProvider
+    private let fogResolverManager: FogResolverManager
+    private let feeFetcher: BlockchainFeeFetcher
+
+    init(accountKey: AccountKeyWithFog, config: Config) {
+        logger.info("""
+            Initializing \(Self.self):
+            \(Self.configDescription(accountKey: accountKey, config: config))
+            """, logFunction: false)
+
+        self.serialQueue = DispatchQueue(label: "com.mobilecoin.\(Self.self)")
+        self.callbackQueue = config.callbackQueue ?? DispatchQueue.main
+        self.accountLock = .init(Account(accountKey: accountKey))
+        self.txOutSelectionStrategy = config.txOutSelectionStrategy
+        self.mixinSelectionStrategy = config.mixinSelectionStrategy
+        self.fogQueryScalingStrategy = config.fogQueryScalingStrategy
+
+        self.serviceProvider =
+            DefaultServiceProvider(networkConfig: config.networkConfig, targetQueue: serialQueue)
+        self.fogResolverManager = FogResolverManager(
+            fogReportAttestation: config.networkConfig.fogReportAttestation,
+            serviceProvider: serviceProvider,
+            targetQueue: serialQueue)
+        self.feeFetcher = BlockchainFeeFetcher(
+            blockchainService: serviceProvider.blockchainService,
+            minimumFeeCacheTTL: config.minimumFeeCacheTTL,
+            targetQueue: serialQueue)
+    }
+
+    public var balance: Balance {
+        accountLock.readSync { $0.cachedBalance }
+    }
+
+    public var accountActivity: AccountActivity {
+        accountLock.readSync { $0.cachedAccountActivity }
+    }
+
+    public func setTransportProtocol(_ transportProtocol: TransportProtocol) {
+        serviceProvider.setTransportProtocolOption(transportProtocol.option)
+    }
+
+    public func setConsensusBasicAuthorization(username: String, password: String) {
+        let credentials = BasicCredentials(username: username, password: password)
+        serviceProvider.setConsensusAuthorization(credentials: credentials)
+    }
+
+    public func setFogBasicAuthorization(username: String, password: String) {
+        let credentials = BasicCredentials(username: username, password: password)
+        serviceProvider.setFogUserAuthorization(credentials: credentials)
+    }
+
+    public func updateBalance(completion: @escaping (Result<Balance, ConnectionError>) -> Void) {
+        Account.BalanceUpdater(
+            account: accountLock,
+            fogViewService: serviceProvider.fogViewService,
+            fogKeyImageService: serviceProvider.fogKeyImageService,
+            fogBlockService: serviceProvider.fogBlockService,
+            fogQueryScalingStrategy: fogQueryScalingStrategy,
+            targetQueue: serialQueue
+        ).updateBalance { result in
+            self.callbackQueue.async {
+                completion(result)
+            }
+        }
+    }
+
+    public func amountTransferable(
+        feeLevel: FeeLevel = .minimum,
+        completion: @escaping (Result<UInt64, BalanceTransferEstimationFetcherError>) -> Void
+    ) {
+        Account.TransactionEstimator(
+            account: accountLock,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            targetQueue: serialQueue
+        ).amountTransferable(feeLevel: feeLevel, completion: completion)
+    }
+
+    public func estimateTotalFee(
+        toSendAmount amount: UInt64,
+        feeLevel: FeeLevel = .minimum,
+        completion: @escaping (Result<UInt64, TransactionEstimationFetcherError>) -> Void
+    ) {
+        Account.TransactionEstimator(
+            account: accountLock,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            targetQueue: serialQueue
+        ).estimateTotalFee(toSendAmount: amount, feeLevel: feeLevel, completion: completion)
+    }
+
+    public func requiresDefragmentation(
+        toSendAmount amount: UInt64,
+        feeLevel: FeeLevel = .minimum,
+        completion: @escaping (Result<Bool, TransactionEstimationFetcherError>) -> Void
+    ) {
+        Account.TransactionEstimator(
+            account: accountLock,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            targetQueue: serialQueue
+        ).requiresDefragmentation(toSendAmount: amount, feeLevel: feeLevel, completion: completion)
+    }
+
+    public func prepareTransaction(
+        to recipient: PublicAddress,
+        amount: UInt64,
+        fee: UInt64,
+        completion: @escaping (
+            Result<(transaction: Transaction, receipt: Receipt), TransactionPreparationError>
+        ) -> Void
+    ) {
+        Account.TransactionOperations(
+            account: accountLock,
+            fogMerkleProofService: serviceProvider.fogMerkleProofService,
+            fogResolverManager: fogResolverManager,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            mixinSelectionStrategy: mixinSelectionStrategy,
+            targetQueue: serialQueue
+        ).prepareTransaction(to: recipient, amount: amount, fee: fee) { result in
+            self.callbackQueue.async {
+                completion(result)
+            }
+        }
+    }
+
+    public func prepareTransaction(
+        to recipient: PublicAddress,
+        amount: UInt64,
+        feeLevel: FeeLevel = .minimum,
+        completion: @escaping (
+            Result<(transaction: Transaction, receipt: Receipt), TransactionPreparationError>
+        ) -> Void
+    ) {
+        Account.TransactionOperations(
+            account: accountLock,
+            fogMerkleProofService: serviceProvider.fogMerkleProofService,
+            fogResolverManager: fogResolverManager,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            mixinSelectionStrategy: mixinSelectionStrategy,
+            targetQueue: serialQueue
+        ).prepareTransaction(to: recipient, amount: amount, feeLevel: feeLevel) { result in
+            self.callbackQueue.async {
+                completion(result)
+            }
+        }
+    }
+
+    public func prepareDefragmentationStepTransactions(
+        toSendAmount amount: UInt64,
+        feeLevel: FeeLevel = .minimum,
+        completion: @escaping (Result<[Transaction], DefragTransactionPreparationError>) -> Void
+    ) {
+        Account.TransactionOperations(
+            account: accountLock,
+            fogMerkleProofService: serviceProvider.fogMerkleProofService,
+            fogResolverManager: fogResolverManager,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            mixinSelectionStrategy: mixinSelectionStrategy,
+            targetQueue: serialQueue
+        ).prepareDefragmentationStepTransactions(toSendAmount: amount, feeLevel: feeLevel)
+        { result in
+            self.callbackQueue.async {
+                completion(result)
+            }
+        }
+    }
+
+    public func submitTransaction(
+        _ transaction: Transaction,
+        completion: @escaping (Result<(), TransactionSubmissionError>) -> Void
+    ) {
+        TransactionSubmitter(
+            consensusService: serviceProvider.consensusService,
+            feeFetcher: feeFetcher
+        ).submitTransaction(transaction) { result in
+            self.callbackQueue.async {
+                completion(result)
+            }
+        }
+    }
+
+    public func status(
+        of transaction: Transaction,
+        completion: @escaping (Result<TransactionStatus, ConnectionError>) -> Void
+    ) {
+        TransactionStatusChecker(
+            account: accountLock,
+            fogUntrustedTxOutService: serviceProvider.fogUntrustedTxOutService,
+            fogKeyImageService: serviceProvider.fogKeyImageService,
+            targetQueue: serialQueue
+        ).checkStatus(transaction) { result in
+            self.callbackQueue.async {
+                completion(result)
+            }
+        }
+    }
+
+    public func status(of receipt: Receipt) -> Result<ReceiptStatus, InvalidInputError> {
+        ReceiptStatusChecker(account: accountLock).status(receipt)
+    }
+}
+
+extension MobileCoinClient {
+    private static func configDescription(accountKey: AccountKeyWithFog, config: Config) -> String {
+        let fogInfo = accountKey.fogInfo
+        return """
+            Consensus url: \(config.networkConfig.consensusUrl.url)
+            Fog url: \(config.networkConfig.fogUrl.url)
+            AccountKey PublicAddress: \
+            \(redacting: Base58Coder.encode(accountKey.accountKey.publicAddress))
+            AccountKey Fog Report url: \(fogInfo.reportUrl.url)
+            AccountKey Fog Report id: \(String(reflecting: fogInfo.reportId))
+            AccountKey Fog Report authority sPKI: 0x\(fogInfo.authoritySpki.hexEncodedString())
+            Consensus attestation: \(config.networkConfig.consensus.attestation)
+            Fog View attestation: \(config.networkConfig.fogView.attestation)
+            Fog KeyImage attestation: \(config.networkConfig.fogKeyImage.attestation)
+            Fog MerkleProof attestation: \(config.networkConfig.fogMerkleProof.attestation)
+            Fog Report attestation: \(config.networkConfig.fogReportAttestation)
+            """
+    }
+}
+
+extension MobileCoinClient {
+    @available(*, deprecated, message: "Use amountTransferable(feeLevel:completion:) instead")
+    public func amountTransferable(feeLevel: FeeLevel = .minimum)
+        -> Result<UInt64, BalanceTransferEstimationError>
+    {
+        Account.TransactionEstimator(
+            account: accountLock,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            targetQueue: serialQueue
+        ).amountTransferable(feeLevel: feeLevel)
+    }
+
+    @available(*, deprecated, message:
+        "Use estimateTotalFee(toSendAmount:feeLevel:completion:) instead")
+    public func estimateTotalFee(
+        toSendAmount amount: UInt64,
+        feeLevel: FeeLevel = .minimum
+    ) -> Result<UInt64, TransactionEstimationError> {
+        Account.TransactionEstimator(
+            account: accountLock,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            targetQueue: serialQueue
+        ).estimateTotalFee(toSendAmount: amount, feeLevel: feeLevel)
+    }
+
+    @available(*, deprecated, message:
+        "Use requiresDefragmentation(toSendAmount:feeLevel:completion:) instead")
+    public func requiresDefragmentation(toSendAmount amount: UInt64, feeLevel: FeeLevel = .minimum)
+        -> Result<Bool, TransactionEstimationError>
+    {
+        Account.TransactionEstimator(
+            account: accountLock,
+            feeFetcher: feeFetcher,
+            txOutSelectionStrategy: txOutSelectionStrategy,
+            targetQueue: serialQueue
+        ).requiresDefragmentation(toSendAmount: amount, feeLevel: feeLevel)
+    }
+}
+
+extension MobileCoinClient {
+    public struct Config {
+        /// - Returns: `InvalidInputError` when `consensusUrl` or `fogUrl` are not well-formed URLs
+        ///     with the appropriate schemes.
+        public static func make(
+            consensusUrl: String,
+            consensusAttestation: Attestation,
+            fogUrl: String,
+            fogViewAttestation: Attestation,
+            fogKeyImageAttestation: Attestation,
+            fogMerkleProofAttestation: Attestation,
+            fogReportAttestation: Attestation
+        ) -> Result<Config, InvalidInputError> {
+            ConsensusUrl.make(string: consensusUrl).flatMap { consensusUrl in
+                FogUrl.make(string: fogUrl).map { fogUrl in
+                    let attestationConfig = NetworkConfig.AttestationConfig(
+                        consensus: consensusAttestation,
+                        fogView: fogViewAttestation,
+                        fogKeyImage: fogKeyImageAttestation,
+                        fogMerkleProof: fogMerkleProofAttestation,
+                        fogReport: fogReportAttestation)
+                    let networkConfig = NetworkConfig(
+                        consensusUrl: consensusUrl,
+                        fogUrl: fogUrl,
+                        attestation: attestationConfig)
+                    return Config(networkConfig: networkConfig)
+                }
+            }
+        }
+
+        fileprivate var networkConfig: NetworkConfig
+
+        // default minimum fee cache TTL is 30 minutes
+        public var minimumFeeCacheTTL: TimeInterval = 30 * 60
+
+        public var cacheStorageAdapter: StorageAdapter?
+
+        /// The `DispatchQueue` on which all `MobileCoinClient` completion handlers will be called.
+        /// If `nil`, `DispatchQueue.main` will be used.
+        public var callbackQueue: DispatchQueue?
+
+        var txOutSelectionStrategy: TxOutSelectionStrategy = DefaultTxOutSelectionStrategy()
+        var mixinSelectionStrategy: MixinSelectionStrategy = DefaultMixinSelectionStrategy()
+        var fogQueryScalingStrategy: FogQueryScalingStrategy = DefaultFogQueryScalingStrategy()
+
+        init(networkConfig: NetworkConfig) {
+            self.networkConfig = networkConfig
+        }
+
+        public var transportProtocol: TransportProtocol {
+            get { networkConfig.transportProtocol }
+            set { networkConfig.transportProtocol = newValue }
+        }
+
+        public mutating func setConsensusTrustRoots(_ trustRoots: [Data])
+            -> Result<(), InvalidInputError>
+        {
+            Self.parseTrustRoots(trustRootsBytes: trustRoots).map {
+                networkConfig.consensusTrustRoots = $0
+            }
+        }
+
+        public mutating func setFogTrustRoots(_ trustRoots: [Data]) -> Result<(), InvalidInputError>
+        {
+            Self.parseTrustRoots(trustRootsBytes: trustRoots).map {
+                networkConfig.fogTrustRoots = $0
+            }
+        }
+
+        public mutating func setConsensusBasicAuthorization(username: String, password: String) {
+            networkConfig.consensusAuthorization =
+                BasicCredentials(username: username, password: password)
+        }
+
+        public mutating func setFogBasicAuthorization(username: String, password: String) {
+            networkConfig.fogUserAuthorization =
+                BasicCredentials(username: username, password: password)
+        }
+
+        public var httpRequester: HttpRequester? {
+            get { networkConfig.httpRequester }
+            set { networkConfig.httpRequester = newValue }
+        }
+
+        private static func parseTrustRoots(trustRootsBytes: [Data])
+            -> Result<[NIOSSLCertificate], InvalidInputError>
+        {
+            var trustRoots: [NIOSSLCertificate] = []
+            for trustRootBytes in trustRootsBytes {
+                do {
+                    trustRoots.append(
+                        try NIOSSLCertificate(bytes: Array(trustRootBytes), format: .der))
+                } catch {
+                    let errorMessage = "Error parsing trust root certificate: " +
+                        "\(trustRootBytes.base64EncodedString()) - Error: \(error)"
+                    logger.error(errorMessage, logFunction: false)
+                    return .failure(InvalidInputError(errorMessage))
+                }
+            }
+            return .success(trustRoots)
+        }
+    }
+}
--- a/Sources/Network/Attestation/AttestAke.swift
+++ b/Sources/Network/Attestation/AttestAke.swift
@ -0,0 +1,274 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+import LibMobileCoin
+
+enum AttestAkeError: Error {
+    case invalidInput(String)
+    case attestationVerificationFailed(String)
+}
+
+extension AttestAkeError: CustomStringConvertible {
+    var description: String {
+        "Attest Ake error: " + {
+            switch self {
+            case .invalidInput(let reason):
+                return "Invalid input: \(reason)"
+            case .attestationVerificationFailed(let reason):
+                return "Attestation verification failed: \(reason)"
+            }
+        }()
+    }
+}
+
+enum AeadError: Error {
+    case aead(String)
+    case cipher(String)
+}
+
+extension AeadError: CustomStringConvertible {
+    var description: String {
+        "Aead error: " + {
+            switch self {
+            case .aead(let reason):
+                return "Aead: \(reason)"
+            case .cipher(let reason):
+                return "Cipher: \(reason)"
+            }
+        }()
+    }
+}
+
+final class AttestAke {
+    private var state: State = .unattested
+
+    func authBeginRequest(
+        responderId: String,
+        rng: (@convention(c) (UnsafeMutableRawPointer?) -> UInt64)? = nil,
+        rngContext: Any? = nil
+    ) -> Attest_AuthMessage {
+        var request = Attest_AuthMessage()
+        request.data = authBeginRequestData(
+            responderId: responderId,
+            rng: rng,
+            rngContext: rngContext)
+        return request
+    }
+
+    func authBeginRequestData(
+        responderId: String,
+        rng: (@convention(c) (UnsafeMutableRawPointer?) -> UInt64)? = nil,
+        rngContext: Any? = nil
+    ) -> Data {
+        let ffi = FfiAttestAke()
+        let requestData = ffi.authBeginRequestData(
+            responderId: responderId,
+            rng: rng,
+            rngContext: rngContext)
+        state = .authPending(ffi)
+        return requestData
+    }
+
+    @discardableResult
+    func authEnd(authResponse: Attest_AuthMessage, attestationVerifier: AttestationVerifier)
+        -> Result<Cipher, AttestAkeError>
+    {
+        authEnd(authResponseData: authResponse.data, attestationVerifier: attestationVerifier)
+    }
+
+    @discardableResult
+    func authEnd(authResponseData: Data, attestationVerifier: AttestationVerifier)
+        -> Result<Cipher, AttestAkeError>
+    {
+        guard case .authPending(let attestAke) = state else {
+            return .failure(.invalidInput("AttestAke.authEnd called without a pending auth."))
+        }
+
+        return attestAke.authEnd(
+            authResponseData: authResponseData,
+            attestationVerifier: attestationVerifier
+        ).map {
+            state = .attested(attestAke)
+            return Cipher(attestAke)
+        }
+    }
+
+    var isAttested: Bool {
+        if case .attested = state {
+            return true
+        } else {
+            return false
+        }
+    }
+
+    var cipher: Cipher? {
+        if case .attested(let attestAke) = state {
+            return Cipher(attestAke)
+        } else {
+            return nil
+        }
+    }
+
+    func deattest() {
+        state = .unattested
+    }
+}
+
+extension AttestAke {
+    struct Cipher {
+        private let ffi: FfiAttestAke
+
+        fileprivate init(_ ffi: FfiAttestAke) {
+            self.ffi = ffi
+        }
+
+        var binding: Data {
+            // Safety: ffi is guaranteed to be attested at this point, so ffi.binding() should
+            // never fail.
+            ffi.binding
+        }
+
+        func encryptMessage(aad: Data, plaintext: Data)
+            -> Result<Attest_Message, AeadError>
+        {
+            var message = Attest_Message()
+            message.aad = aad
+            message.channelID = binding
+            return encrypt(aad: aad, plaintext: plaintext).map {
+                message.data = $0
+                return message
+            }
+        }
+
+        func encrypt(aad: Data, plaintext: Data) -> Result<Data, AeadError> {
+            ffi.encrypt(aad: aad, plaintext: plaintext)
+        }
+
+        func decryptMessage(_ message: Attest_Message) -> Result<Data, AeadError> {
+            decrypt(aad: message.aad, ciphertext: message.data)
+        }
+
+        func decrypt(aad: Data, ciphertext: Data) -> Result<Data, AeadError> {
+            ffi.decrypt(aad: aad, ciphertext: ciphertext)
+        }
+    }
+}
+
+extension AttestAke {
+    private enum State {
+        case unattested
+        case authPending(FfiAttestAke)
+        case attested(FfiAttestAke)
+    }
+}
+
+private final class FfiAttestAke {
+    private let ptr: OpaquePointer
+
+    init() {
+        // Safety: mc_attest_ake_create should never return nil.
+        self.ptr = withMcInfallible(mc_attest_ake_create)
+    }
+
+    deinit {
+        mc_attest_ake_free(ptr)
+    }
+
+    var isAttested: Bool {
+        var attested = false
+        withMcInfallible {
+            mc_attest_ake_is_attested(ptr, &attested)
+        }
+        return attested
+    }
+
+    var binding: Data {
+        Data(withMcMutableBufferInfallible: { bufferPtr in
+            mc_attest_ake_get_binding(ptr, bufferPtr)
+        })
+    }
+
+    func authBeginRequestData(
+        responderId: String,
+        rng: (@convention(c) (UnsafeMutableRawPointer?) -> UInt64)? = nil,
+        rngContext: Any? = nil
+    ) -> Data {
+        withMcRngCallback(rng: rng, rngContext: rngContext) { rngCallbackPtr in
+            Data(withMcMutableBufferInfallible: { bufferPtr in
+                mc_attest_ake_get_auth_request(ptr, responderId, rngCallbackPtr, bufferPtr)
+            })
+        }
+    }
+
+    func authEnd(authResponseData: Data, attestationVerifier: AttestationVerifier)
+        -> Result<(), AttestAkeError>
+    {
+        authResponseData.asMcBuffer { bytesPtr in
+            attestationVerifier.withUnsafeOpaquePointer { attestationVerifierPtr in
+                withMcError { errorPtr in
+                    mc_attest_ake_process_auth_response(
+                        ptr,
+                        bytesPtr,
+                        attestationVerifierPtr,
+                        &errorPtr)
+                }.mapError {
+                    switch $0.errorCode {
+                    case .invalidInput:
+                        return .invalidInput("\(redacting: $0.description)")
+                    case .attestationVerificationFailed:
+                        return .attestationVerificationFailed("\(redacting: $0.description)")
+                    default:
+                        // Safety: mc_attest_ake_process_auth_response should not throw
+                        // non-documented errors.
+                        logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+                    }
+                }
+            }
+        }
+    }
+
+    func encrypt(aad: Data, plaintext: Data) -> Result<Data, AeadError> {
+        aad.asMcBuffer { aadPtr in
+            plaintext.asMcBuffer { plaintextPtr in
+                Data.make(withMcMutableBuffer: { ciphertextOutPtr, errorPtr in
+                    mc_attest_ake_encrypt(ptr, aadPtr, plaintextPtr, ciphertextOutPtr, &errorPtr)
+                }).mapError {
+                    switch $0.errorCode {
+                    case .aead:
+                        return .aead("\(redacting: $0.description)")
+                    case .cipher:
+                        return .cipher("\(redacting: $0.description)")
+                    default:
+                        // Safety: mc_attest_ake_encrypt should not throw non-documented errors.
+                        logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+                    }
+                }
+            }
+        }
+    }
+
+    func decrypt(aad: Data, ciphertext: Data) -> Result<Data, AeadError> {
+        aad.asMcBuffer { aadPtr in
+            ciphertext.asMcBuffer { ciphertextPtr in
+                Data.make(withEstimatedLengthMcMutableBuffer: ciphertext.count)
+                { plaintextOutPtr, errorPtr in
+                    mc_attest_ake_decrypt(ptr, aadPtr, ciphertextPtr, plaintextOutPtr, &errorPtr)
+                }.mapError {
+                    switch $0.errorCode {
+                    case .aead:
+                        return .aead("\(redacting: $0.description)")
+                    case .cipher:
+                        return .cipher("\(redacting: $0.description)")
+                    default:
+                        // Safety: mc_attest_ake_decrypt should not throw non-documented errors.
+                        logger.fatalError("Unhandled LibMobileCoin error: \(redacting: $0)")
+                    }
+                }
+            }
+        }
+    }
+}
--- a/Sources/Network/Attestation/Attestation.swift
+++ b/Sources/Network/Attestation/Attestation.swift
@ -0,0 +1,187 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+// swiftlint:disable multiline_function_chains
+
+import Foundation
+
+public struct Attestation {
+    static func make(
+        mrSigner: Data,
+        productId: UInt16,
+        minimumSecurityVersion: UInt16,
+        allowedConfigAdvisories: [String] = [],
+        allowedHardeningAdvisories: [String] = []
+    ) -> Result<Attestation, InvalidInputError> {
+        MrSigner.make(
+            mrSigner: mrSigner,
+            productId: productId,
+            minimumSecurityVersion: minimumSecurityVersion,
+            allowedConfigAdvisories: allowedConfigAdvisories,
+            allowedHardeningAdvisories: allowedHardeningAdvisories
+        ).map { mrSigner in
+            Attestation(mrSigners: [mrSigner])
+        }
+    }
+
+    let mrEnclaves: [MrEnclave]
+    let mrSigners: [MrSigner]
+
+    public init(_ mrSigner: MrSigner) {
+        self.init(mrEnclaves: [], mrSigners: [mrSigner])
+    }
+
+    public init(mrEnclaves: [MrEnclave] = [], mrSigners: [MrSigner] = []) {
+        self.mrEnclaves = mrEnclaves
+        self.mrSigners = mrSigners
+    }
+
+    init(
+        mrSigner: Data32,
+        productId: UInt16,
+        minimumSecurityVersion: UInt16,
+        allowedConfigAdvisories: [String] = [],
+        allowedHardeningAdvisories: [String] = []
+    ) {
+        let mrSigner = MrSigner(
+            mrSigner: mrSigner,
+            productId: productId,
+            minimumSecurityVersion: minimumSecurityVersion,
+            allowedConfigAdvisories: allowedConfigAdvisories,
+            allowedHardeningAdvisories: allowedHardeningAdvisories)
+        self.init(mrSigners: [mrSigner])
+    }
+}
+
+extension Attestation: CustomStringConvertible {
+    public var description: String {
+        var params: [String] = []
+        if mrEnclaves.count == 1 && mrSigners.isEmpty, let mrEnclave = mrEnclaves.first {
+            params.append("\(mrEnclave)")
+        } else if mrSigners.count == 1 && mrEnclaves.isEmpty, let mrSigner = mrSigners.first {
+            params.append("\(mrSigner)")
+        } else {
+            if !mrEnclaves.isEmpty {
+                params.append("mrEnclaves: \(mrEnclaves)")
+            }
+            if !mrSigners.isEmpty {
+                params.append("mrSigners: \(mrSigners)")
+            }
+        }
+        return "Attestation(\(params.joined(separator: ", ")))"
+    }
+}
+
+extension Attestation {
+    public struct MrEnclave {
+        let mrEnclave: Data32
+        let allowedConfigAdvisories: [String]
+        let allowedHardeningAdvisories: [String]
+
+        /// - Returns: `InvalidInputError` when `mrEnclave` is not 32 bytes in length.
+        public static func make(
+            mrEnclave: Data,
+            allowedConfigAdvisories: [String] = [],
+            allowedHardeningAdvisories: [String] = []
+        ) -> Result<MrEnclave, InvalidInputError> {
+            guard let mrEnclave32 = Data32(mrEnclave) else {
+                let errorMessage = "mrEnclave must be 32 bytes in length. mrEnclave: " +
+                    "\(mrEnclave.hexEncodedString())"
+                logger.error(errorMessage, logFunction: false)
+                return .failure(InvalidInputError(errorMessage))
+            }
+            return .success(MrEnclave(
+                mrEnclave: mrEnclave32,
+                allowedConfigAdvisories: allowedConfigAdvisories,
+                allowedHardeningAdvisories: allowedHardeningAdvisories))
+        }
+
+        init(
+            mrEnclave: Data32,
+            allowedConfigAdvisories: [String] = [],
+            allowedHardeningAdvisories: [String] = []
+        ) {
+            self.mrEnclave = mrEnclave
+            self.allowedConfigAdvisories = allowedConfigAdvisories
+            self.allowedHardeningAdvisories = allowedHardeningAdvisories
+        }
+    }
+}
+
+extension Attestation.MrEnclave: CustomStringConvertible {
+    public var description: String {
+        var params = ["0x\(mrEnclave.hexEncodedString())"]
+        if !allowedConfigAdvisories.isEmpty {
+            params.append("allowedConfigAdvisories: \(allowedConfigAdvisories)")
+        }
+        if !allowedHardeningAdvisories.isEmpty {
+            params.append("allowedHardeningAdvisories: \(allowedHardeningAdvisories)")
+        }
+        return "MrEnclave(\(params.joined(separator: ", ")))"
+    }
+}
+
+extension Attestation {
+    public struct MrSigner {
+        let mrSigner: Data32
+        let productId: UInt16
+        let minimumSecurityVersion: UInt16
+        let allowedConfigAdvisories: [String]
+        let allowedHardeningAdvisories: [String]
+
+        /// - Returns: `InvalidInputError` when `mrSigner` is not 32 bytes in length.
+        public static func make(
+            mrSigner: Data,
+            productId: UInt16,
+            minimumSecurityVersion: UInt16,
+            allowedConfigAdvisories: [String] = [],
+            allowedHardeningAdvisories: [String] = []
+        ) -> Result<MrSigner, InvalidInputError> {
+            guard let mrSigner32 = Data32(mrSigner) else {
+                let errorMessage =
+                    "mrSigner must be 32 bytes in length. mrSigner: \(mrSigner.hexEncodedString())"
+                logger.error(errorMessage, logFunction: false)
+                return .failure(InvalidInputError(errorMessage))
+            }
+
+            return .success(MrSigner(
+                mrSigner: mrSigner32,
+                productId: productId,
+                minimumSecurityVersion: minimumSecurityVersion,
+                allowedConfigAdvisories: allowedConfigAdvisories,
+                allowedHardeningAdvisories: allowedHardeningAdvisories))
+        }
+
+        init(
+            mrSigner: Data32,
+            productId: UInt16,
+            minimumSecurityVersion: UInt16,
+            allowedConfigAdvisories: [String] = [],
+            allowedHardeningAdvisories: [String] = []
+        ) {
+            self.mrSigner = mrSigner
+            self.productId = productId
+            self.minimumSecurityVersion = minimumSecurityVersion
+            self.allowedConfigAdvisories = allowedConfigAdvisories
+            self.allowedHardeningAdvisories = allowedHardeningAdvisories
+        }
+    }
+}
+
+extension Attestation.MrSigner: CustomStringConvertible {
+    public var description: String {
+        var params = [
+            "0x\(mrSigner.hexEncodedString())",
+            "productId: \(productId)",
+            "minimumSecurityVersion: \(minimumSecurityVersion)",
+        ]
+        if !allowedConfigAdvisories.isEmpty {
+            params.append("allowedConfigAdvisories: \(allowedConfigAdvisories)")
+        }
+        if !allowedHardeningAdvisories.isEmpty {
+            params.append("allowedHardeningAdvisories: \(allowedHardeningAdvisories)")
+        }
+        return "MrSigner(\(params.joined(separator: ", ")))"
+    }
+}
--- a/Sources/Network/Attestation/AttestationVerifier.swift
+++ b/Sources/Network/Attestation/AttestationVerifier.swift
@ -0,0 +1,119 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import LibMobileCoin
+
+final class AttestationVerifier {
+    private let ptr: OpaquePointer
+
+    init(attestation: Attestation) {
+        // Safety: mc_verifier_create should never return nil.
+        self.ptr = withMcInfallible(mc_verifier_create)
+
+        attestation.mrEnclaves.forEach(addMrEnclave)
+        attestation.mrSigners.forEach(addMrSigner)
+    }
+
+    deinit {
+        mc_verifier_free(ptr)
+    }
+
+    func withUnsafeOpaquePointer<R>(_ body: (OpaquePointer) throws -> R) rethrows -> R {
+        try body(ptr)
+    }
+
+    private func addMrEnclave(_ mrEnclave: Attestation.MrEnclave) {
+        let ffiMrEnclaveVerifier = MrEnclaveVerifier(mrEnclave: mrEnclave)
+        ffiMrEnclaveVerifier.withUnsafeOpaquePointer { ffiMrEnclaveVerifierPtr in
+            // Safety: mc_verifier_add_mr_enclave should never fail.
+            withMcInfallible { mc_verifier_add_mr_enclave(ptr, ffiMrEnclaveVerifierPtr) }
+        }
+    }
+
+    private func addMrSigner(_ mrSigner: Attestation.MrSigner) {
+        let ffiMrSignerVerifier = MrSignerVerifier(mrSigner: mrSigner)
+        ffiMrSignerVerifier.withUnsafeOpaquePointer { ffiMrSignerVerifierPtr in
+            // Safety: mc_verifier_add_mr_signer should never fail.
+            withMcInfallible { mc_verifier_add_mr_signer(ptr, ffiMrSignerVerifierPtr) }
+        }
+    }
+}
+
+private final class MrEnclaveVerifier {
+    private let ptr: OpaquePointer
+
+    init(mrEnclave: Attestation.MrEnclave) {
+        self.ptr = mrEnclave.mrEnclave.asMcBuffer { mrEnclavePtr in
+            // Safety: mc_mr_enclave_verifier_create should never fail.
+            withMcInfallible { mc_mr_enclave_verifier_create(mrEnclavePtr) }
+        }
+
+        mrEnclave.allowedConfigAdvisories.forEach(addConfigAdvisory)
+        mrEnclave.allowedHardeningAdvisories.forEach(addHardeningAdvisory)
+    }
+
+    deinit {
+        mc_mr_enclave_verifier_free(ptr)
+    }
+
+    func withUnsafeOpaquePointer<R>(_ body: (OpaquePointer) throws -> R) rethrows -> R {
+        try body(ptr)
+    }
+
+    private func addConfigAdvisory(advisoryId: String) {
+        advisoryId.withCString { advisoryIdPtr in
+            // Safety: mc_mr_enclave_verifier_allow_config_advisory should never fail.
+            withMcInfallible { mc_mr_enclave_verifier_allow_config_advisory(ptr, advisoryIdPtr) }
+        }
+    }
+
+    private func addHardeningAdvisory(advisoryId: String) {
+        advisoryId.withCString { advisoryIdPtr in
+            // Safety: mc_mr_enclave_verifier_allow_hardening_advisory should never fail.
+            withMcInfallible { mc_mr_enclave_verifier_allow_hardening_advisory(ptr, advisoryIdPtr) }
+        }
+    }
+}
+
+private final class MrSignerVerifier {
+    private let ptr: OpaquePointer
+
+    init(mrSigner: Attestation.MrSigner) {
+        self.ptr = mrSigner.mrSigner.asMcBuffer { mrSignerPtr in
+            // Safety: mc_mr_signer_verifier_create should never fail.
+            withMcInfallible {
+                mc_mr_signer_verifier_create(
+                    mrSignerPtr,
+                    mrSigner.productId,
+                    mrSigner.minimumSecurityVersion)
+            }
+        }
+
+        mrSigner.allowedConfigAdvisories.forEach(addConfigAdvisory)
+        mrSigner.allowedHardeningAdvisories.forEach(addHardeningAdvisory)
+    }
+
+    deinit {
+        mc_mr_signer_verifier_free(ptr)
+    }
+
+    func withUnsafeOpaquePointer<R>(_ body: (OpaquePointer) throws -> R) rethrows -> R {
+        try body(ptr)
+    }
+
+    private func addConfigAdvisory(advisoryId: String) {
+        advisoryId.withCString { advisoryIdPtr in
+            // Safety: mc_mr_signer_verifier_allow_config_advisory should never fail.
+            withMcInfallible { mc_mr_signer_verifier_allow_config_advisory(ptr, advisoryIdPtr) }
+        }
+    }
+
+    private func addHardeningAdvisory(advisoryId: String) {
+        advisoryId.withCString { advisoryIdPtr in
+            // Safety: mc_mr_signer_verifier_allow_hardening_advisory should never fail.
+            withMcInfallible { mc_mr_signer_verifier_allow_hardening_advisory(ptr, advisoryIdPtr) }
+        }
+    }
+}
--- a/Sources/Network/AttestedConnectionConfig.swift
+++ b/Sources/Network/AttestedConnectionConfig.swift
@ -0,0 +1,34 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+import NIOSSL
+
+protocol AttestedConnectionConfigProtocol: ConnectionConfigProtocol {
+    var attestation: Attestation { get }
+}
+
+struct AttestedConnectionConfig<Url: MobileCoinUrlProtocol>: AttestedConnectionConfigProtocol {
+    let urlTyped: Url
+    let transportProtocolOption: TransportProtocol.Option
+    let attestation: Attestation
+    let trustRoots: [NIOSSLCertificate]?
+    let authorization: BasicCredentials?
+
+    init(
+        url: Url,
+        transportProtocolOption: TransportProtocol.Option,
+        attestation: Attestation,
+        trustRoots: [NIOSSLCertificate]?,
+        authorization: BasicCredentials?
+    ) {
+        self.urlTyped = url
+        self.transportProtocolOption = transportProtocolOption
+        self.attestation = attestation
+        self.trustRoots = trustRoots
+        self.authorization = authorization
+    }
+
+    var url: MobileCoinUrlProtocol { urlTyped }
+}
--- a/Sources/Network/Authorization/BasicCredentials.swift
+++ b/Sources/Network/Authorization/BasicCredentials.swift
@ -0,0 +1,15 @@
+//
+//  Copyright (c) 2020-2021 MobileCoin. All rights reserved.
+//
+
+import Foundation
+
+struct BasicCredentials {
+    let username: String
+    let password: String
+
+    var authorizationHeaderValue: String {
+        let credentials = "\(username):\(password)"
+        return "Basic \(Data(credentials.utf8).base64EncodedString())"
+    }
+}
--- a/Show More
+++ b/Show More