diff --git a/SignalMetadataKit/src/ECPublicKey.swift b/SignalMetadataKit/src/ECPublicKey.swift
index a27d985..cbab429 100644
--- a/SignalMetadataKit/src/ECPublicKey.swift
+++ b/SignalMetadataKit/src/ECPublicKey.swift
@@ -43,7 +43,7 @@ import Foundation
 
     @objc public var serialized: Data {
         let typeBytes = [ECPublicKey.keyTypeDJB]
-        let typeData = Data(bytes: typeBytes)
+        let typeData = Data(typeBytes)
         return NSData.join([typeData, keyData])
     }
 
diff --git a/SignalMetadataKit/src/SMKSecretSessionCipher.swift b/SignalMetadataKit/src/SMKSecretSessionCipher.swift
index 399e493..7362b7e 100644
--- a/SignalMetadataKit/src/SMKSecretSessionCipher.swift
+++ b/SignalMetadataKit/src/SMKSecretSessionCipher.swift
@@ -158,7 +158,7 @@ public class SMKDecryptResult: NSObject {
                                           deviceId: Int32,
                                           paddedPlaintext: Data,
                                           senderCertificate: SMKSenderCertificate,
-                                          protocolContext: Any?) throws -> Data {
+                                          protocolContext: SPKProtocolWriteContext?) throws -> Data {
         guard recipientId.count > 0 else {
             throw SMKError.assertionError(description: "\(SMKSecretSessionCipher.logTag) invalid recipientId")
         }
@@ -270,7 +270,7 @@ public class SMKDecryptResult: NSObject {
                                           timestamp: UInt64,
                                           localRecipientId: String,
                                           localDeviceId: Int32,
-                                          protocolContext: Any?) throws -> SMKDecryptResult {
+                                          protocolContext: SPKProtocolWriteContext?) throws -> SMKDecryptResult {
 
         guard timestamp > 0 else {
             throw SMKError.assertionError(description: "\(logTag) invalid timestamp")
@@ -509,7 +509,7 @@ public class SMKDecryptResult: NSObject {
     // throws InvalidVersionException, InvalidMessageException, InvalidKeyException, DuplicateMessageException,
     // InvalidKeyIdException, UntrustedIdentityException, LegacyMessageException, NoSessionException
     private func throwswrapped_decrypt(messageContent: SMKUnidentifiedSenderMessageContent,
-                                    protocolContext: Any?) throws -> Data {
+                                       protocolContext: SPKProtocolWriteContext?) throws -> Data {
 
         // SignalProtocolAddress sender = new SignalProtocolAddress(message.getSenderCertificate().getSender(),
         // message.getSenderCertificate().getSenderDeviceId());
diff --git a/SignalMetadataKit/src/SMKUnidentifiedSenderMessage.swift b/SignalMetadataKit/src/SMKUnidentifiedSenderMessage.swift
index 5592d2e..6cd4a67 100644
--- a/SignalMetadataKit/src/SMKUnidentifiedSenderMessage.swift
+++ b/SignalMetadataKit/src/SMKUnidentifiedSenderMessage.swift
@@ -86,7 +86,7 @@ import Foundation
     @objc public func serialized() throws -> Data {
         let versionByte: UInt8 = UInt8((self.cipherTextVersion << 4 | self.cipherTextVersion) & 0xFF)
         let versionBytes = [versionByte]
-        let versionData = Data(bytes: versionBytes)
+        let versionData = Data(versionBytes)
         let messageData = try toProto().serializedData()
 
         return NSData.join([versionData, messageData])