diff --git a/Signal/src/ViewControllers/ConversationView/ConversationMessageMapping.swift b/Signal/src/ViewControllers/ConversationView/ConversationMessageMapping.swift
index 497b60d418..c77885a7e6 100644
--- a/Signal/src/ViewControllers/ConversationView/ConversationMessageMapping.swift
+++ b/Signal/src/ViewControllers/ConversationView/ConversationMessageMapping.swift
@@ -200,7 +200,7 @@ public class ConversationMessageMapping: NSObject {
             throw assertionError("could not find interaction")
         }
 
-        let threadInteractionCount = try interactionFinder.count(transaction: transaction)
+        let threadInteractionCount = interactionFinder.count(transaction: transaction)
         guard index < threadInteractionCount else {
             throw assertionError("invalid index")
         }
diff --git a/Signal/src/ViewControllers/DebugUI/DebugUIMessages+OWS.swift b/Signal/src/ViewControllers/DebugUI/DebugUIMessages+OWS.swift
index 88e624ed00..443a92da4a 100644
--- a/Signal/src/ViewControllers/DebugUI/DebugUIMessages+OWS.swift
+++ b/Signal/src/ViewControllers/DebugUI/DebugUIMessages+OWS.swift
@@ -12,7 +12,7 @@ public extension DebugUIMessages {
 
         let interactionFinder = InteractionFinder(threadUniqueId: thread.uniqueId!)
 
-        let messageCount = try! interactionFinder.count(transaction: transaction)
+        let messageCount = interactionFinder.count(transaction: transaction)
 
         var messageIndices: [UInt] = Array((0..<messageCount))
         var interactions: [TSInteraction] = []
diff --git a/Signal/src/ViewControllers/MediaGallery/MediaGalleryViewController.swift b/Signal/src/ViewControllers/MediaGallery/MediaGalleryViewController.swift
index 286e0f1c0e..8029cbbf1b 100644
--- a/Signal/src/ViewControllers/MediaGallery/MediaGalleryViewController.swift
+++ b/Signal/src/ViewControllers/MediaGallery/MediaGalleryViewController.swift
@@ -87,8 +87,12 @@ public class MediaGalleryItem: Equatable, Hashable {
 
     // MARK: Hashable
 
-    public var hashValue: Int {
-        return attachmentStream.uniqueId?.hashValue ?? attachmentStream.hashValue
+    public func hash(into hasher: inout Hasher) {
+        if let uniqueId = attachmentStream.uniqueId {
+            hasher.combine(uniqueId)
+        } else {
+            hasher.combine(attachmentStream)
+        }
     }
 
     // MARK: Sorting
@@ -185,8 +189,9 @@ public struct GalleryDate: Hashable, Comparable, Equatable {
 
     // MARK: Hashable
 
-    public var hashValue: Int {
-        return month.hashValue ^ year.hashValue
+    public func hash(into hasher: inout Hasher) {
+        hasher.combine(month)
+        hasher.combine(year)
     }
 
     // MARK: Comparable
diff --git a/Signal/src/ViewControllers/Photos/PhotoCapture.swift b/Signal/src/ViewControllers/Photos/PhotoCapture.swift
index 8ce42fe565..01cb5d4f11 100644
--- a/Signal/src/ViewControllers/Photos/PhotoCapture.swift
+++ b/Signal/src/ViewControllers/Photos/PhotoCapture.swift
@@ -461,7 +461,7 @@ extension PhotoCapture: CaptureOutputDelegate {
         // AVCaptureMovieFileOutput records to .mov, but for compatibility we need to send mp4's.
         // Because we take care to record with h264 compression (not hevc), this conversion
         // doesn't require re-encoding the media streams and happens quickly.
-        let (attachmentPromise, exportSession) = SignalAttachment.compressVideoAsMp4(dataSource: dataSource, dataUTI: kUTTypeMPEG4 as String)
+        let (attachmentPromise, _) = SignalAttachment.compressVideoAsMp4(dataSource: dataSource, dataUTI: kUTTypeMPEG4 as String)
         attachmentPromise.map { [weak self] attachment in
             guard let self = self else { return }
             self.delegate?.photoCapture(self, didFinishProcessingAttachment: attachment)
diff --git a/Signal/src/ViewControllers/Photos/SendMediaNavigationController.swift b/Signal/src/ViewControllers/Photos/SendMediaNavigationController.swift
index 39376a53ca..e60b18de26 100644
--- a/Signal/src/ViewControllers/Photos/SendMediaNavigationController.swift
+++ b/Signal/src/ViewControllers/Photos/SendMediaNavigationController.swift
@@ -603,7 +603,7 @@ private struct CameraCaptureAttachment: Hashable, Equatable {
     }
 
     func hash(into hasher: inout Hasher) {
-        signalAttachment.hash(into: &hasher)
+        hasher.combine(signalAttachment)
     }
 
     static func ==(lhs: CameraCaptureAttachment, rhs: CameraCaptureAttachment) -> Bool {
@@ -616,7 +616,7 @@ private struct MediaLibraryAttachment: Hashable, Equatable {
     let attachmentApprovalItemPromise: Promise<AttachmentApprovalItem>
 
     func hash(into hasher: inout Hasher) {
-        asset.hash(into: &hasher)
+        hasher.combine(asset)
     }
 
     static func ==(lhs: MediaLibraryAttachment, rhs: MediaLibraryAttachment) -> Bool {
diff --git a/Signal/src/call/CallAudioService.swift b/Signal/src/call/CallAudioService.swift
index 488ccaf3fc..844ec5f997 100644
--- a/Signal/src/call/CallAudioService.swift
+++ b/Signal/src/call/CallAudioService.swift
@@ -77,12 +77,14 @@ struct AudioSource: Hashable {
         return lhsPortDescription.uid == rhsPortDescription.uid
     }
 
-    var hashValue: Int {
+    public func hash(into hasher: inout Hasher) {
         guard let portDescription = self.portDescription else {
             assert(self.isBuiltInSpeaker)
-            return "Built In Speaker".hashValue
+            hasher.combine("Built In Speaker")
+            return
         }
-        return portDescription.uid.hash
+
+        hasher.combine(portDescription.uid)
     }
 }
 
diff --git a/Signal/src/util/UI Categories/AVAudioSession+OWS.h b/Signal/src/util/UI Categories/AVAudioSession+OWS.h
index 1e8f7483b5..a1db570e50 100644
--- a/Signal/src/util/UI Categories/AVAudioSession+OWS.h	
+++ b/Signal/src/util/UI Categories/AVAudioSession+OWS.h	
@@ -2,7 +2,7 @@
 //  Copyright (c) 2019 Open Whisper Systems. All rights reserved.
 //
 
-#import <AVFoundation/AVAudioSession.h>
+#import <AVFoundation/AVFoundation.h>
 
 NS_ASSUME_NONNULL_BEGIN
 
diff --git a/Signal/src/views/MarqueeLabel.swift b/Signal/src/views/MarqueeLabel.swift
index d892299f27..a78766a796 100644
--- a/Signal/src/views/MarqueeLabel.swift
+++ b/Signal/src/views/MarqueeLabel.swift
@@ -240,7 +240,7 @@ open class MarqueeLabel: UILabel, CAAnimationDelegate {
         }
     }
 
-    @available(*, deprecated : 2.6, message : "Use speed property instead")
+    @available(iOS, deprecated: 2.6, message : "Use speed property instead")
     @IBInspectable open var scrollDuration: CGFloat {
         get {
             switch speed {
@@ -253,7 +253,7 @@ open class MarqueeLabel: UILabel, CAAnimationDelegate {
         }
     }
 
-    @available(*, deprecated : 2.6, message : "Use speed property instead")
+    @available(iOS, deprecated: 2.6, message : "Use speed property instead")
     @IBInspectable open var scrollRate: CGFloat {
         get {
             switch speed {
diff --git a/Signal/test/mocks/MockEnvironment.h b/Signal/test/mocks/MockEnvironment.h
index 5406613f7f..db330cf4a5 100644
--- a/Signal/test/mocks/MockEnvironment.h
+++ b/Signal/test/mocks/MockEnvironment.h
@@ -12,11 +12,6 @@ NS_ASSUME_NONNULL_BEGIN
 
 - (instancetype)init;
 
-@property (nonatomic) OWSContactsManager *contactsManager;
-@property (nonatomic) OWSPreferences *preferences;
-@property (nonatomic) OWSSounds *sounds;
-@property (nonatomic) OWSWindowManager *windowManager;
-
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/Signal/test/util/ByteParserTest.swift b/Signal/test/util/ByteParserTest.swift
index dac0b9136f..0f8ef2ee00 100644
--- a/Signal/test/util/ByteParserTest.swift
+++ b/Signal/test/util/ByteParserTest.swift
@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2019 Open Whisper Systems. All rights reserved.
 //
 
 import XCTest
@@ -26,7 +26,7 @@ class ByteParserTest: SignalBaseTest {
     }
 
     func testGetShort_littleEndian() {
-        let data = Data(bytes: [0x01, 0x00, 0x00, 0x01, 0x01, 0x01 ])
+        let data = Data([0x01, 0x00, 0x00, 0x01, 0x01, 0x01])
         let parser = ByteParser(data: data, littleEndian: true)
         XCTAssertNotNil(parser)
         XCTAssertFalse(parser.hasError)
@@ -45,7 +45,7 @@ class ByteParserTest: SignalBaseTest {
     }
 
     func testGetShort_bigEndian() {
-        let data = Data(bytes: [0x01, 0x00, 0x00, 0x01, 0x01, 0x01 ])
+        let data = Data([0x01, 0x00, 0x00, 0x01, 0x01, 0x01])
         let parser = ByteParser(data: data, littleEndian: false)
         XCTAssertNotNil(parser)
         XCTAssertFalse(parser.hasError)
@@ -73,7 +73,7 @@ class ByteParserTest: SignalBaseTest {
     }
 
     func testGetInt_littleEndian() {
-        let data = Data(bytes: [0x01, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00 ])
+        let data = Data([0x01, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00])
         let parser = ByteParser(data: data, littleEndian: true)
         XCTAssertNotNil(parser)
         XCTAssertFalse(parser.hasError)
@@ -92,7 +92,7 @@ class ByteParserTest: SignalBaseTest {
     }
 
     func testGetInt_bigEndian() {
-        let data = Data(bytes: [0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x01, 0x01 ])
+        let data = Data([0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x01, 0x01])
         let parser = ByteParser(data: data, littleEndian: false)
         XCTAssertNotNil(parser)
         XCTAssertFalse(parser.hasError)
@@ -120,7 +120,7 @@ class ByteParserTest: SignalBaseTest {
     }
 
     func testGetLong_littleEndian() {
-        let data = Data(bytes: [0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ])
+        let data = Data([0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00])
         let parser = ByteParser(data: data, littleEndian: true)
         XCTAssertNotNil(parser)
         XCTAssertFalse(parser.hasError)
@@ -139,7 +139,7 @@ class ByteParserTest: SignalBaseTest {
     }
 
     func testGetLong_bigEndian() {
-        let data = Data(bytes: [0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01 ])
+        let data = Data([0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01])
         let parser = ByteParser(data: data, littleEndian: false)
         XCTAssertNotNil(parser)
         XCTAssertFalse(parser.hasError)
@@ -167,7 +167,7 @@ class ByteParserTest: SignalBaseTest {
     }
 
     func testReadZero() {
-        let data = Data(bytes: [0x00, 0x01, 0x00, 0x00, 0x01, 0x00])
+        let data = Data([0x00, 0x01, 0x00, 0x00, 0x01, 0x00])
         let parser = ByteParser(data: data, littleEndian: true)
         XCTAssertNotNil(parser)
         XCTAssertFalse(parser.hasError)
@@ -198,21 +198,21 @@ class ByteParserTest: SignalBaseTest {
     }
 
     func testReadBytes() {
-        let data = Data(bytes: [0x00, 0x01, 0x02, 0x03, 0x04, 0x05])
+        let data = Data([0x00, 0x01, 0x02, 0x03, 0x04, 0x05])
         let parser = ByteParser(data: data, littleEndian: true)
         XCTAssertNotNil(parser)
         XCTAssertFalse(parser.hasError)
 
-        XCTAssertEqual(Data(bytes: [0x00 ]), parser.readBytes(1))
+        XCTAssertEqual(Data([0x00]), parser.readBytes(1))
         XCTAssertFalse(parser.hasError)
 
-        XCTAssertEqual(Data(bytes: [0x01 ]), parser.readBytes(1))
+        XCTAssertEqual(Data([0x01]), parser.readBytes(1))
         XCTAssertFalse(parser.hasError)
 
-        XCTAssertEqual(Data(bytes: [0x02, 0x03]), parser.readBytes(2))
+        XCTAssertEqual(Data([0x02, 0x03]), parser.readBytes(2))
         XCTAssertFalse(parser.hasError)
 
-        XCTAssertEqual(Data(bytes: [0x04, 0x05]), parser.readBytes(2))
+        XCTAssertEqual(Data([0x04, 0x05]), parser.readBytes(2))
         XCTAssertFalse(parser.hasError)
 
         XCTAssertNil(parser.readBytes(1))
diff --git a/SignalMessaging/ViewControllers/AttachmentApproval/AttachmentItemCollection.swift b/SignalMessaging/ViewControllers/AttachmentApproval/AttachmentItemCollection.swift
index 2dd54afe38..1b03c9fe01 100644
--- a/SignalMessaging/ViewControllers/AttachmentApproval/AttachmentItemCollection.swift
+++ b/SignalMessaging/ViewControllers/AttachmentApproval/AttachmentItemCollection.swift
@@ -61,7 +61,7 @@ public class AttachmentApprovalItem: Hashable {
     // MARK: Hashable
 
     public func hash(into hasher: inout Hasher) {
-        return attachment.hash(into: &hasher)
+        return hasher.combine(attachment)
     }
 
     // MARK: Equatable
diff --git a/SignalMessaging/ViewControllers/Stickers/ManageStickersViewController.swift b/SignalMessaging/ViewControllers/Stickers/ManageStickersViewController.swift
index 6390b1b200..b3e2d3e1ca 100644
--- a/SignalMessaging/ViewControllers/Stickers/ManageStickersViewController.swift
+++ b/SignalMessaging/ViewControllers/Stickers/ManageStickersViewController.swift
@@ -217,7 +217,7 @@ public class ManageStickersViewController: OWSTableViewController {
     }
 
     private func buildTableCell(installedStickerPack stickerPack: StickerPack) -> UITableViewCell {
-        var actionIconName = CurrentAppContext().isRTL ? "reply-filled-24" : "reply-filled-reversed-24"
+        let actionIconName = CurrentAppContext().isRTL ? "reply-filled-24" : "reply-filled-reversed-24"
         return buildTableCell(stickerPack: stickerPack,
                               stickerInfo: stickerPack.coverInfo,
                               title: stickerPack.title,
diff --git a/SignalMessaging/categories/UIFont+OWS.m b/SignalMessaging/categories/UIFont+OWS.m
index 904e4371e6..d818882160 100644
--- a/SignalMessaging/categories/UIFont+OWS.m
+++ b/SignalMessaging/categories/UIFont+OWS.m
@@ -123,7 +123,7 @@ NS_ASSUME_NONNULL_BEGIN
             UIFontTextStyleCaption1 : @(18.0),
             UIFontTextStyleCaption2 : @(17.0),
         } mutableCopy];
-        if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(11, 0)) {
+        if (@available(iOS 11.0, *)) {
             map[UIFontTextStyleLargeTitle] = @(40.0);
         }
         maxPointSizeMap = map;
@@ -144,7 +144,7 @@ NS_ASSUME_NONNULL_BEGIN
 
 + (UIFont *)ows_dynamicTypeLargeTitle1ClampedFont
 {
-    if (SYSTEM_VERSION_GREATER_THAN_OR_EQUAL_TO(11, 0)) {
+    if (@available(iOS 11.0, *)) {
         return [UIFont preferredFontForTextStyleClamped:UIFontTextStyleLargeTitle];
     } else {
         return [UIFont preferredFontForTextStyleClamped:UIFontTextStyleTitle1];
diff --git a/SignalMessaging/contacts/SystemContactsFetcher.swift b/SignalMessaging/contacts/SystemContactsFetcher.swift
index 10049983cf..3c9f595a5e 100644
--- a/SignalMessaging/contacts/SystemContactsFetcher.swift
+++ b/SignalMessaging/contacts/SystemContactsFetcher.swift
@@ -357,7 +357,8 @@ public class SystemContactsFetcher: NSObject {
             }
 
             Logger.info("fetched \(contacts.count) contacts.")
-            let contactsHash  = HashableArray(contacts).hashValue
+
+            let contactsHash = contacts.hashValue
 
             DispatchQueue.main.async {
                 var shouldNotifyDelegate = false
@@ -414,25 +415,3 @@ public class SystemContactsFetcher: NSObject {
         return contactStoreAdapter.fetchCNContact(contactId: contactId)
     }
 }
-
-struct HashableArray<Element: Hashable>: Hashable {
-    var elements: [Element]
-    init(_ elements: [Element]) {
-        self.elements = elements
-    }
-
-    var hashValue: Int {
-        // random generated 32bit number
-        let base = 224712574
-        var position = 0
-        return elements.reduce(base) { (result, element) -> Int in
-            // Make sure change in sort order invalidates hash
-            position += 1
-            return result ^ element.hashValue + position
-        }
-    }
-
-    static func == (lhs: HashableArray, rhs: HashableArray) -> Bool {
-        return lhs.hashValue == rhs.hashValue
-    }
-}
diff --git a/SignalServiceKit/src/Contacts/OWSContactDiscoveryOperation.swift b/SignalServiceKit/src/Contacts/OWSContactDiscoveryOperation.swift
index 30b3440d76..d206128614 100644
--- a/SignalServiceKit/src/Contacts/OWSContactDiscoveryOperation.swift
+++ b/SignalServiceKit/src/Contacts/OWSContactDiscoveryOperation.swift
@@ -462,6 +462,8 @@ class CDSFeedbackOperation: OWSOperation {
                     self.makeRequest(result: .unexpectedError(reason: "CDS assertionError: \(reason ?? "unknown")"))
                 case .attestationFailed:
                     self.makeRequest(result: .attestationError(reason: "CDS attestationFailed: \(reason ?? "unknown")"))
+                @unknown default:
+                    self.makeRequest(result: .unexpectedError(reason: "CDS assertionError: unknown cdsError.code"))
                 }
             case ContactDiscoveryError.assertionError(let assertionDescription):
                 self.makeRequest(result: .unexpectedError(reason: "assertionError: \(assertionDescription)"))
diff --git a/SignalServiceKit/src/Messages/TSCall.h b/SignalServiceKit/src/Messages/TSCall.h
index 3f2b9da646..94cc73648a 100644
--- a/SignalServiceKit/src/Messages/TSCall.h
+++ b/SignalServiceKit/src/Messages/TSCall.h
@@ -34,15 +34,6 @@ NSString *NSStringFromCallType(RPRecentCallType callType);
                          callType:(RPRecentCallType)callType
                          inThread:(TSContactThread *)thread NS_DESIGNATED_INITIALIZER;
 
-- (instancetype)initWithUniqueId:(NSString *)uniqueId
-             receivedAtTimestamp:(uint64_t)receivedAtTimestamp
-                          sortId:(uint64_t)sortId
-                       timestamp:(uint64_t)timestamp
-                  uniqueThreadId:(NSString *)uniqueThreadId
-               callSchemaVersion:(NSUInteger)callSchemaVersion
-                        callType:(RPRecentCallType)callType
-                            read:(BOOL)read NS_DESIGNATED_INITIALIZER;
-
 // --- CODE GENERATION MARKER
 
 // This snippet is generated by /Scripts/sds_codegen/sds_generate.py. Do not manually edit it, instead run `sds_codegen.sh`.
diff --git a/SignalServiceKit/src/Storage/Jobs/SSKJobRecord.h b/SignalServiceKit/src/Storage/Jobs/SSKJobRecord.h
index 2e02ede71d..27f351c55a 100644
--- a/SignalServiceKit/src/Storage/Jobs/SSKJobRecord.h
+++ b/SignalServiceKit/src/Storage/Jobs/SSKJobRecord.h
@@ -15,7 +15,7 @@ typedef NS_ERROR_ENUM(SSKJobRecordErrorDomain, JobRecordError){
     JobRecordError_IllegalStateTransition,
 };
 
-typedef NS_ENUM(NSUInteger, SSKJobRecordStatus) {
+typedef NS_CLOSED_ENUM(NSUInteger, SSKJobRecordStatus){
     SSKJobRecordStatus_Unknown,
     SSKJobRecordStatus_Ready,
     SSKJobRecordStatus_Running,
diff --git a/SignalServiceKit/src/Util/JobQueue.swift b/SignalServiceKit/src/Util/JobQueue.swift
index 7e7a4d4d58..ea80f5f208 100644
--- a/SignalServiceKit/src/Util/JobQueue.swift
+++ b/SignalServiceKit/src/Util/JobQueue.swift
@@ -205,11 +205,7 @@ public extension JobQueue {
         databaseStorage.write { transaction in
             let runningRecords = self.finder.allRecords(label: self.jobRecordLabel, status: .running, transaction: transaction)
             Logger.info("marking old `running` JobRecords as ready: \(runningRecords.count)")
-            for record in runningRecords {
-                guard let jobRecord = record as? JobRecordType else {
-                    owsFailDebug("unexpected jobRecord: \(record)")
-                    continue
-                }
+            for jobRecord in runningRecords {
                 do {
                     try jobRecord.saveRunningAsReady(transaction: transaction)
                     self.didMarkAsReady(oldJobRecord: jobRecord, transaction: transaction)
diff --git a/SignalServiceKit/tests/Devices/OWSProvisioningCipherTest.m b/SignalServiceKit/tests/Devices/OWSProvisioningCipherTest.m
index 359259a76f..ea08d82e4d 100644
--- a/SignalServiceKit/tests/Devices/OWSProvisioningCipherTest.m
+++ b/SignalServiceKit/tests/Devices/OWSProvisioningCipherTest.m
@@ -1,5 +1,5 @@
 //
-//  Copyright (c) 2018 Open Whisper Systems. All rights reserved.
+//  Copyright (c) 2019 Open Whisper Systems. All rights reserved.
 //
 
 #import "SSKBaseTestObjC.h"
@@ -77,10 +77,15 @@
     NSKeyedArchiver *archiver = [NSKeyedArchiver new];
     [archiver encodeBytes:publicKeyBytes length:ECCKeyLength forKey:@"TSECKeyPairPublicKey"];
     [archiver encodeBytes:privateKeyBytes length:ECCKeyLength forKey:@"TSECKeyPairPrivateKey"];
-    NSData *serialized = [archiver encodedData];
-    
-    NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:serialized];
-    return [[ECKeyPair alloc] initWithCoder:unarchiver];
+
+    if (@available(iOS 10.0, *)) {
+        NSData *serialized = [archiver encodedData];
+        NSKeyedUnarchiver *unarchiver = [[NSKeyedUnarchiver alloc] initForReadingWithData:serialized];
+        return [[ECKeyPair alloc] initWithCoder:unarchiver];
+    } else {
+        XCTFail(@"This test is only supported on iOS10+");
+        return [ECKeyPair new];
+    }
 }
 
 - (NSData *)knownData
diff --git a/SignalShareExtension/ShareViewController.swift b/SignalShareExtension/ShareViewController.swift
index 9d717217b9..9def7f1d27 100644
--- a/SignalShareExtension/ShareViewController.swift
+++ b/SignalShareExtension/ShareViewController.swift
@@ -691,15 +691,11 @@ public class ShareViewController: UIViewController, ShareViewDelegate, SAEFailed
             }
             return isUrlItem(itemProvider: itemProvider)
         }) {
-            if let itemProvider = preferredAttachment as? NSItemProvider {
-                return [itemProvider]
-            } else {
-                owsFailDebug("Unexpected attachment type: \(String(describing: preferredAttachment))")
-            }
+            return [preferredAttachment]
         }
 
         // else return whatever is available
-        if let itemProvider = inputItem.attachments?.first as? NSItemProvider {
+        if let itemProvider = inputItem.attachments?.first {
             return [itemProvider]
         } else {
             owsFailDebug("Missing attachment.")