diff --git a/Podfile b/Podfile
index 552a0ab1c..d4dcaf516 100644
--- a/Podfile
+++ b/Podfile
@@ -105,9 +105,11 @@ end
 
 target 'SessionProtocolKit' do
   pod 'CocoaLumberjack', :inhibit_warnings => true
+  pod 'CryptoSwift', :inhibit_warnings => true
   pod 'Curve25519Kit', :inhibit_warnings => true
   pod 'GRKOpenSSLFramework', :inhibit_warnings => true
   pod 'HKDFKit', :inhibit_warnings => true
+  pod 'PromiseKit', :inhibit_warnings => true
   pod 'SwiftProtobuf', '~> 1.5.0', :inhibit_warnings => true
 end
 
diff --git a/Podfile.lock b/Podfile.lock
index 47689c383..681d0317a 100644
--- a/Podfile.lock
+++ b/Podfile.lock
@@ -332,6 +332,6 @@ SPEC CHECKSUMS:
   YYImage: 6db68da66f20d9f169ceb94dfb9947c3867b9665
   ZXingObjC: fdbb269f25dd2032da343e06f10224d62f537bdb
 
-PODFILE CHECKSUM: 821988dba010cf44893aecf26652d7da531868f0
+PODFILE CHECKSUM: 58acf63b2164dadf743187b6a52154721c1c01dd
 
 COCOAPODS: 1.10.0.rc.1
diff --git a/Pods b/Pods
index 24da46b65..03a39c064 160000
--- a/Pods
+++ b/Pods
@@ -1 +1 @@
-Subproject commit 24da46b65b9581625f18cd9dac30b310401e84f2
+Subproject commit 03a39c064860412e9e69b99f19dd85cd5a9b8aad
diff --git a/SessionProtocolKit/Configuration.swift b/SessionProtocolKit/Configuration.swift
new file mode 100644
index 000000000..d05ff5769
--- /dev/null
+++ b/SessionProtocolKit/Configuration.swift
@@ -0,0 +1,14 @@
+
+public struct Configuration {
+    public let storage: SessionProtocolKitStorageProtocol
+    public let sharedSenderKeysDelegate: SharedSenderKeysDelegate
+
+    internal static var shared: Configuration!
+}
+
+public enum SessionProtocolKit { // Just to make the external API nice
+
+    public static func configure(with configuration: Configuration) {
+        Configuration.shared = configuration
+    }
+}
diff --git a/SessionProtocolKit/Shared Sender Keys/ClosedGroupRatchet.swift b/SessionProtocolKit/Shared Sender Keys/ClosedGroupRatchet.swift
new file mode 100644
index 000000000..e87e982ef
--- /dev/null
+++ b/SessionProtocolKit/Shared Sender Keys/ClosedGroupRatchet.swift	
@@ -0,0 +1,45 @@
+import SessionUtilities
+
+public final class ClosedGroupRatchet : NSObject, NSCoding {
+    public let chainKey: String
+    public let keyIndex: UInt
+    public let messageKeys: [String]
+
+    // MARK: Initialization
+    public init(chainKey: String, keyIndex: UInt, messageKeys: [String]) {
+        self.chainKey = chainKey
+        self.keyIndex = keyIndex
+        self.messageKeys = messageKeys
+    }
+
+    // MARK: Coding
+    public init?(coder: NSCoder) {
+        guard let chainKey = coder.decodeObject(forKey: "chainKey") as? String,
+            let keyIndex = coder.decodeObject(forKey: "keyIndex") as? UInt,
+            let messageKeys = coder.decodeObject(forKey: "messageKeys") as? [String] else { return nil }
+        self.chainKey = chainKey
+        self.keyIndex = UInt(keyIndex)
+        self.messageKeys = messageKeys
+        super.init()
+    }
+
+    public func encode(with coder: NSCoder) {
+        coder.encode(chainKey, forKey: "chainKey")
+        coder.encode(keyIndex, forKey: "keyIndex")
+        coder.encode(messageKeys, forKey: "messageKeys")
+    }
+
+    // MARK: Equality
+    override public func isEqual(_ other: Any?) -> Bool {
+        guard let other = other as? ClosedGroupRatchet else { return false }
+        return chainKey == other.chainKey && keyIndex == other.keyIndex && messageKeys == other.messageKeys
+    }
+
+    // MARK: Hashing
+    override public var hash: Int { // Override NSObject.hash and not Hashable.hashValue or Hashable.hash(into:)
+        return chainKey.hashValue ^ keyIndex.hashValue ^ messageKeys.hashValue
+    }
+
+    // MARK: Description
+    override public var description: String { return "[ chainKey : \(chainKey), keyIndex : \(keyIndex), messageKeys : \(messageKeys.prettifiedDescription) ]" }
+}
diff --git a/SessionProtocolKit/Shared Sender Keys/ClosedGroupSenderKey.swift b/SessionProtocolKit/Shared Sender Keys/ClosedGroupSenderKey.swift
new file mode 100644
index 000000000..27e1e6625
--- /dev/null
+++ b/SessionProtocolKit/Shared Sender Keys/ClosedGroupSenderKey.swift	
@@ -0,0 +1,46 @@
+
+public final class ClosedGroupSenderKey : NSObject, NSCoding {
+    public let chainKey: Data
+    public let keyIndex: UInt
+    public let publicKey: Data
+
+    // MARK: Initialization
+    init(chainKey: Data, keyIndex: UInt, publicKey: Data) {
+        self.chainKey = chainKey
+        self.keyIndex = keyIndex
+        self.publicKey = publicKey
+    }
+
+    // MARK: Coding
+    public init?(coder: NSCoder) {
+        guard let chainKey = coder.decodeObject(forKey: "chainKey") as? Data,
+            let keyIndex = coder.decodeObject(forKey: "keyIndex") as? UInt,
+            let publicKey = coder.decodeObject(forKey: "publicKey") as? Data else { return nil }
+        self.chainKey = chainKey
+        self.keyIndex = UInt(keyIndex)
+        self.publicKey = publicKey
+        super.init()
+    }
+
+    public func encode(with coder: NSCoder) {
+        coder.encode(chainKey, forKey: "chainKey")
+        coder.encode(keyIndex, forKey: "keyIndex")
+        coder.encode(publicKey, forKey: "publicKey")
+    }
+
+    // MARK: Equality
+    override public func isEqual(_ other: Any?) -> Bool {
+        guard let other = other as? ClosedGroupSenderKey else { return false }
+        return chainKey == other.chainKey && keyIndex == other.keyIndex && publicKey == other.publicKey
+    }
+
+    // MARK: Hashing
+    override public var hash: Int { // Override NSObject.hash and not Hashable.hashValue or Hashable.hash(into:)
+        return chainKey.hashValue ^ keyIndex.hashValue ^ publicKey.hashValue
+    }
+
+    // MARK: Description
+    override public var description: String {
+        return "[ chainKey : \(chainKey), keyIndex : \(keyIndex), publicKey: \(publicKey.toHexString()) ]"
+    }
+}
diff --git a/SessionProtocolKit/Shared Sender Keys/SharedSenderKeys.swift b/SessionProtocolKit/Shared Sender Keys/SharedSenderKeys.swift
new file mode 100644
index 000000000..d86ab6c5e
--- /dev/null
+++ b/SessionProtocolKit/Shared Sender Keys/SharedSenderKeys.swift	
@@ -0,0 +1,172 @@
+import CryptoSwift
+import PromiseKit
+import SessionUtilities
+
+public enum SharedSenderKeys {
+    private static let gcmTagSize: UInt = 16
+    private static let ivSize: UInt = 12
+
+    // MARK: Ratcheting Error
+    public enum RatchetingError : LocalizedError {
+        case loadingFailed(groupPublicKey: String, senderPublicKey: String)
+        case messageKeyMissing(targetKeyIndex: UInt, groupPublicKey: String, senderPublicKey: String)
+        case generic
+
+        public var errorDescription: String? {
+            switch self {
+            case .loadingFailed(let groupPublicKey, let senderPublicKey): return "Couldn't get ratchet for closed group with public key: \(groupPublicKey), sender public key: \(senderPublicKey)."
+            case .messageKeyMissing(let targetKeyIndex, let groupPublicKey, let senderPublicKey): return "Couldn't find message key for old key index: \(targetKeyIndex), public key: \(groupPublicKey), sender public key: \(senderPublicKey)."
+            case .generic: return "An error occurred"
+            }
+        }
+    }
+
+    // MARK: Private/Internal API
+    internal func generateRatchet(for groupPublicKey: String, senderPublicKey: String, using transaction: Any) -> ClosedGroupRatchet {
+        let rootChainKey = Data.getSecureRandomData(ofSize: 32)!.toHexString()
+        let ratchet = ClosedGroupRatchet(chainKey: rootChainKey, keyIndex: 0, messageKeys: [])
+        Configuration.shared.storage.setClosedGroupRatchet(for: groupPublicKey, senderPublicKey: senderPublicKey, ratchet: ratchet, in: .current, using: transaction)
+        return ratchet
+    }
+
+    private func step(_ ratchet: ClosedGroupRatchet) throws -> ClosedGroupRatchet {
+        let nextMessageKey = try HMAC(key: Data(hex: ratchet.chainKey).bytes, variant: .sha256).authenticate([ UInt8(1) ])
+        let nextChainKey = try HMAC(key: Data(hex: ratchet.chainKey).bytes, variant: .sha256).authenticate([ UInt8(2) ])
+        let nextKeyIndex = ratchet.keyIndex + 1
+        let messageKeys = ratchet.messageKeys + [ nextMessageKey.toHexString() ]
+        return ClosedGroupRatchet(chainKey: nextChainKey.toHexString(), keyIndex: nextKeyIndex, messageKeys: messageKeys)
+    }
+
+    /// - Note: Sync. Don't call from the main thread.
+    private func stepRatchetOnce(for groupPublicKey: String, senderPublicKey: String, using transaction: Any) throws -> ClosedGroupRatchet {
+        #if DEBUG
+        assert(!Thread.isMainThread)
+        #endif
+        guard let ratchet = Configuration.shared.storage.getClosedGroupRatchet(for: groupPublicKey, senderPublicKey: senderPublicKey, from: .current) else {
+            let error = RatchetingError.loadingFailed(groupPublicKey: groupPublicKey, senderPublicKey: senderPublicKey)
+            print("[Loki] \(error.errorDescription!)")
+            throw error
+        }
+        do {
+            let result = try step(ratchet)
+            Configuration.shared.storage.setClosedGroupRatchet(for: groupPublicKey, senderPublicKey: senderPublicKey, ratchet: result, in: .current, using: transaction)
+            return result
+        } catch {
+            print("[Loki] Couldn't step ratchet due to error: \(error).")
+            throw error
+        }
+    }
+
+    /// - Note: Sync. Don't call from the main thread.
+    private func stepRatchet(for groupPublicKey: String, senderPublicKey: String, until targetKeyIndex: UInt, using transaction: Any, isRetry: Bool = false) throws -> ClosedGroupRatchet {
+        #if DEBUG
+        assert(!Thread.isMainThread)
+        #endif
+        let collection: ClosedGroupRatchetCollectionType = (isRetry) ? .old : .current
+        guard let ratchet = Configuration.shared.storage.getClosedGroupRatchet(for: groupPublicKey, senderPublicKey: senderPublicKey, from: collection) else {
+            let error = RatchetingError.loadingFailed(groupPublicKey: groupPublicKey, senderPublicKey: senderPublicKey)
+            print("[Loki] \(error.errorDescription!)")
+            throw error
+        }
+        if targetKeyIndex < ratchet.keyIndex {
+            // There's no need to advance the ratchet if this is invoked for an old key index
+            guard ratchet.messageKeys.count > targetKeyIndex else {
+                let error = RatchetingError.messageKeyMissing(targetKeyIndex: targetKeyIndex, groupPublicKey: groupPublicKey, senderPublicKey: senderPublicKey)
+                print("[Loki] \(error.errorDescription!)")
+                throw error
+            }
+            return ratchet
+        } else {
+            var currentKeyIndex = ratchet.keyIndex
+            var result = ratchet
+            while currentKeyIndex < targetKeyIndex {
+                do {
+                    result = try step(result)
+                    currentKeyIndex = result.keyIndex
+                } catch {
+                    print("[Loki] Couldn't step ratchet due to error: \(error).")
+                    throw error
+                }
+            }
+            let collection: ClosedGroupRatchetCollectionType = (isRetry) ? .old : .current
+            Configuration.shared.storage.setClosedGroupRatchet(for: groupPublicKey, senderPublicKey: senderPublicKey, ratchet: result, in: collection, using: transaction)
+            return result
+        }
+    }
+
+    // MARK: Public API
+    public func encrypt(_ plaintext: Data, for groupPublicKey: String, senderPublicKey: String, using transaction: Any) throws -> (ivAndCiphertext: Data, keyIndex: UInt) {
+        let ratchet: ClosedGroupRatchet
+        do {
+            ratchet = try stepRatchetOnce(for: groupPublicKey, senderPublicKey: senderPublicKey, using: transaction)
+        } catch {
+            // FIXME: It'd be cleaner to handle this in OWSMessageDecrypter (where all the other decryption errors are handled), but this was a lot more
+            // convenient because there's an easy way to get the sender public key from here.
+            if case RatchetingError.loadingFailed(_, _) = error {
+                Configuration.shared.sharedSenderKeysDelegate.requestSenderKey(for: groupPublicKey, senderPublicKey: senderPublicKey, using: transaction)
+            }
+            throw error
+        }
+        let iv = Data.getSecureRandomData(ofSize: SharedSenderKeys.ivSize)!
+        let gcm = GCM(iv: iv.bytes, tagLength: Int(SharedSenderKeys.gcmTagSize), mode: .combined)
+        let messageKey = ratchet.messageKeys.last!
+        let aes = try AES(key: Data(hex: messageKey).bytes, blockMode: gcm, padding: .noPadding)
+        let ciphertext = try aes.encrypt(plaintext.bytes)
+        return (ivAndCiphertext: iv + Data(ciphertext), ratchet.keyIndex)
+    }
+
+    public func decrypt(_ ivAndCiphertext: Data, for groupPublicKey: String, senderPublicKey: String, keyIndex: UInt, using transaction: Any, isRetry: Bool = false) throws -> Data {
+        let ratchet: ClosedGroupRatchet
+        do {
+            ratchet = try stepRatchet(for: groupPublicKey, senderPublicKey: senderPublicKey, until: keyIndex, using: transaction, isRetry: isRetry)
+        } catch {
+            if !isRetry {
+                return try decrypt(ivAndCiphertext, for: groupPublicKey, senderPublicKey: senderPublicKey, keyIndex: keyIndex, using: transaction, isRetry: true)
+            } else {
+                // FIXME: It'd be cleaner to handle this in OWSMessageDecrypter (where all the other decryption errors are handled), but this was a lot more
+                // convenient because there's an easy way to get the sender public key from here.
+                if case RatchetingError.loadingFailed(_, _) = error {
+                    Configuration.shared.sharedSenderKeysDelegate.requestSenderKey(for: groupPublicKey, senderPublicKey: senderPublicKey, using: transaction)
+                }
+                throw error
+            }
+        }
+        let iv = ivAndCiphertext[0..<Int(SharedSenderKeys.ivSize)]
+        let ciphertext = ivAndCiphertext[Int(SharedSenderKeys.ivSize)...]
+        let gcm = GCM(iv: iv.bytes, tagLength: Int(SharedSenderKeys.gcmTagSize), mode: .combined)
+        let messageKeys = ratchet.messageKeys
+        let lastNMessageKeys: [String]
+        if messageKeys.count > 16 { // Pick an arbitrary number of message keys to try; this helps resolve issues caused by messages arriving out of order
+            lastNMessageKeys = [String](messageKeys[messageKeys.index(messageKeys.endIndex, offsetBy: -16)..<messageKeys.endIndex])
+        } else {
+            lastNMessageKeys = messageKeys
+        }
+        guard !lastNMessageKeys.isEmpty else {
+            throw RatchetingError.messageKeyMissing(targetKeyIndex: keyIndex, groupPublicKey: groupPublicKey, senderPublicKey: senderPublicKey)
+        }
+        var error: Error?
+        for messageKey in lastNMessageKeys.reversed() { // Reversed because most likely the last one is the one we need
+            let aes = try AES(key: Data(hex: messageKey).bytes, blockMode: gcm, padding: .noPadding)
+            do {
+                return Data(try aes.decrypt(ciphertext.bytes))
+            } catch (let e) {
+                error = e
+            }
+        }
+        if !isRetry {
+            return try decrypt(ivAndCiphertext, for: groupPublicKey, senderPublicKey: senderPublicKey, keyIndex: keyIndex, using: transaction, isRetry: true)
+        } else {
+            Configuration.shared.sharedSenderKeysDelegate.requestSenderKey(for: groupPublicKey, senderPublicKey: senderPublicKey, using: transaction)
+            throw error ?? RatchetingError.generic
+        }
+    }
+
+    public func isClosedGroup(_ publicKey: String) -> Bool {
+        return Configuration.shared.storage.getUserClosedGroupPublicKeys().contains(publicKey)
+    }
+
+    public func getKeyPair(forGroupWithPublicKey groupPublicKey: String) -> ECKeyPair {
+        let privateKey = Configuration.shared.storage.getClosedGroupPrivateKey(for: groupPublicKey)!
+        return ECKeyPair(publicKey: Data(hex: groupPublicKey.removing05PrefixIfNeeded()), privateKey: Data(hex: privateKey))
+    }
+}
diff --git a/SessionProtocolKit/Shared Sender Keys/SharedSenderKeysDelegate.swift b/SessionProtocolKit/Shared Sender Keys/SharedSenderKeysDelegate.swift
new file mode 100644
index 000000000..7ccc9f8c1
--- /dev/null
+++ b/SessionProtocolKit/Shared Sender Keys/SharedSenderKeysDelegate.swift	
@@ -0,0 +1,5 @@
+
+public protocol SharedSenderKeysDelegate {
+
+    func requestSenderKey(for groupPublicKey: String, senderPublicKey: String, using transaction: Any)
+}
diff --git a/SessionProtocolKit/Shared Sender Keys/Storage.swift b/SessionProtocolKit/Shared Sender Keys/Storage.swift
new file mode 100644
index 000000000..a6287349b
--- /dev/null
+++ b/SessionProtocolKit/Shared Sender Keys/Storage.swift	
@@ -0,0 +1,17 @@
+
+public enum ClosedGroupRatchetCollectionType {
+    case old, current
+}
+
+public protocol SessionProtocolKitStorageProtocol {
+
+    func with(_ work: (Any) -> Void)
+
+    func getClosedGroupRatchet(for groupPublicKey: String, senderPublicKey: String, from collection: ClosedGroupRatchetCollectionType) -> ClosedGroupRatchet?
+    func setClosedGroupRatchet(for groupPublicKey: String, senderPublicKey: String, ratchet: ClosedGroupRatchet, in collection: ClosedGroupRatchetCollectionType, using transaction: Any)
+    func getAllClosedGroupRatchets(for groupPublicKey: String, from collection: ClosedGroupRatchetCollectionType) -> [(senderPublicKey: String, ratchet: ClosedGroupRatchet)]
+    func getAllClosedGroupSenderKeys(for groupPublicKey: String, from collection: ClosedGroupRatchetCollectionType) -> Set<ClosedGroupSenderKey>
+    func removeAllClosedGroupRatchets(for groupPublicKey: String, from collection: ClosedGroupRatchetCollectionType, using transaction: Any)
+    func getUserClosedGroupPublicKeys() -> Set<String>
+    func getClosedGroupPrivateKey(for publicKey: String) -> String?
+}
diff --git a/SessionProtocolKit/AxolotlExceptions.h b/SessionProtocolKit/Signal/AxolotlExceptions.h
similarity index 100%
rename from SessionProtocolKit/AxolotlExceptions.h
rename to SessionProtocolKit/Signal/AxolotlExceptions.h
diff --git a/SessionProtocolKit/CipherMessage/CipherMessage.h b/SessionProtocolKit/Signal/CipherMessage/CipherMessage.h
similarity index 100%
rename from SessionProtocolKit/CipherMessage/CipherMessage.h
rename to SessionProtocolKit/Signal/CipherMessage/CipherMessage.h
diff --git a/SessionProtocolKit/CipherMessage/ClosedGroupCiphertextMessage.h b/SessionProtocolKit/Signal/CipherMessage/ClosedGroupCiphertextMessage.h
similarity index 100%
rename from SessionProtocolKit/CipherMessage/ClosedGroupCiphertextMessage.h
rename to SessionProtocolKit/Signal/CipherMessage/ClosedGroupCiphertextMessage.h
diff --git a/SessionProtocolKit/CipherMessage/ClosedGroupCiphertextMessage.m b/SessionProtocolKit/Signal/CipherMessage/ClosedGroupCiphertextMessage.m
similarity index 100%
rename from SessionProtocolKit/CipherMessage/ClosedGroupCiphertextMessage.m
rename to SessionProtocolKit/Signal/CipherMessage/ClosedGroupCiphertextMessage.m
diff --git a/SessionProtocolKit/CipherMessage/FallbackMessage.h b/SessionProtocolKit/Signal/CipherMessage/FallbackMessage.h
similarity index 100%
rename from SessionProtocolKit/CipherMessage/FallbackMessage.h
rename to SessionProtocolKit/Signal/CipherMessage/FallbackMessage.h
diff --git a/SessionProtocolKit/CipherMessage/FallbackMessage.m b/SessionProtocolKit/Signal/CipherMessage/FallbackMessage.m
similarity index 100%
rename from SessionProtocolKit/CipherMessage/FallbackMessage.m
rename to SessionProtocolKit/Signal/CipherMessage/FallbackMessage.m
diff --git a/SessionProtocolKit/CipherMessage/PreKeyWhisperMessage.h b/SessionProtocolKit/Signal/CipherMessage/PreKeyWhisperMessage.h
similarity index 100%
rename from SessionProtocolKit/CipherMessage/PreKeyWhisperMessage.h
rename to SessionProtocolKit/Signal/CipherMessage/PreKeyWhisperMessage.h
diff --git a/SessionProtocolKit/CipherMessage/PreKeyWhisperMessage.m b/SessionProtocolKit/Signal/CipherMessage/PreKeyWhisperMessage.m
similarity index 100%
rename from SessionProtocolKit/CipherMessage/PreKeyWhisperMessage.m
rename to SessionProtocolKit/Signal/CipherMessage/PreKeyWhisperMessage.m
diff --git a/SessionProtocolKit/CipherMessage/WhisperMessage.h b/SessionProtocolKit/Signal/CipherMessage/WhisperMessage.h
similarity index 100%
rename from SessionProtocolKit/CipherMessage/WhisperMessage.h
rename to SessionProtocolKit/Signal/CipherMessage/WhisperMessage.h
diff --git a/SessionProtocolKit/CipherMessage/WhisperMessage.m b/SessionProtocolKit/Signal/CipherMessage/WhisperMessage.m
similarity index 100%
rename from SessionProtocolKit/CipherMessage/WhisperMessage.m
rename to SessionProtocolKit/Signal/CipherMessage/WhisperMessage.m
diff --git a/SessionProtocolKit/Constants.h b/SessionProtocolKit/Signal/Constants.h
similarity index 100%
rename from SessionProtocolKit/Constants.h
rename to SessionProtocolKit/Signal/Constants.h
diff --git a/SessionProtocolKit/Crypto/AES-CBC.h b/SessionProtocolKit/Signal/Crypto/AES-CBC.h
similarity index 100%
rename from SessionProtocolKit/Crypto/AES-CBC.h
rename to SessionProtocolKit/Signal/Crypto/AES-CBC.h
diff --git a/SessionProtocolKit/Crypto/AES-CBC.m b/SessionProtocolKit/Signal/Crypto/AES-CBC.m
similarity index 100%
rename from SessionProtocolKit/Crypto/AES-CBC.m
rename to SessionProtocolKit/Signal/Crypto/AES-CBC.m
diff --git a/SessionProtocolKit/Prekeys/PreKeyBundle.h b/SessionProtocolKit/Signal/Prekeys/PreKeyBundle.h
similarity index 100%
rename from SessionProtocolKit/Prekeys/PreKeyBundle.h
rename to SessionProtocolKit/Signal/Prekeys/PreKeyBundle.h
diff --git a/SessionProtocolKit/Prekeys/PreKeyBundle.m b/SessionProtocolKit/Signal/Prekeys/PreKeyBundle.m
similarity index 100%
rename from SessionProtocolKit/Prekeys/PreKeyBundle.m
rename to SessionProtocolKit/Signal/Prekeys/PreKeyBundle.m
diff --git a/SessionProtocolKit/Prekeys/PreKeyRecord.h b/SessionProtocolKit/Signal/Prekeys/PreKeyRecord.h
similarity index 100%
rename from SessionProtocolKit/Prekeys/PreKeyRecord.h
rename to SessionProtocolKit/Signal/Prekeys/PreKeyRecord.h
diff --git a/SessionProtocolKit/Prekeys/PreKeyRecord.m b/SessionProtocolKit/Signal/Prekeys/PreKeyRecord.m
similarity index 100%
rename from SessionProtocolKit/Prekeys/PreKeyRecord.m
rename to SessionProtocolKit/Signal/Prekeys/PreKeyRecord.m
diff --git a/SessionProtocolKit/Prekeys/SignedPrekeyRecord.h b/SessionProtocolKit/Signal/Prekeys/SignedPrekeyRecord.h
similarity index 100%
rename from SessionProtocolKit/Prekeys/SignedPrekeyRecord.h
rename to SessionProtocolKit/Signal/Prekeys/SignedPrekeyRecord.h
diff --git a/SessionProtocolKit/Prekeys/SignedPrekeyRecord.m b/SessionProtocolKit/Signal/Prekeys/SignedPrekeyRecord.m
similarity index 100%
rename from SessionProtocolKit/Prekeys/SignedPrekeyRecord.m
rename to SessionProtocolKit/Signal/Prekeys/SignedPrekeyRecord.m
diff --git a/SessionProtocolKit/Protos/Makefile b/SessionProtocolKit/Signal/Protos/Makefile
similarity index 100%
rename from SessionProtocolKit/Protos/Makefile
rename to SessionProtocolKit/Signal/Protos/Makefile
diff --git a/SessionProtocolKit/Protos/SPKProto.swift b/SessionProtocolKit/Signal/Protos/SPKProto.swift
similarity index 100%
rename from SessionProtocolKit/Protos/SPKProto.swift
rename to SessionProtocolKit/Signal/Protos/SPKProto.swift
diff --git a/SessionProtocolKit/Protos/WhisperTextProtocol.pb.swift b/SessionProtocolKit/Signal/Protos/WhisperTextProtocol.pb.swift
similarity index 100%
rename from SessionProtocolKit/Protos/WhisperTextProtocol.pb.swift
rename to SessionProtocolKit/Signal/Protos/WhisperTextProtocol.pb.swift
diff --git a/SessionProtocolKit/Protos/WhisperTextProtocol.proto b/SessionProtocolKit/Signal/Protos/WhisperTextProtocol.proto
similarity index 100%
rename from SessionProtocolKit/Protos/WhisperTextProtocol.proto
rename to SessionProtocolKit/Signal/Protos/WhisperTextProtocol.proto
diff --git a/SessionProtocolKit/Ratchet/AliceAxolotlParameters.h b/SessionProtocolKit/Signal/Ratchet/AliceAxolotlParameters.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/AliceAxolotlParameters.h
rename to SessionProtocolKit/Signal/Ratchet/AliceAxolotlParameters.h
diff --git a/SessionProtocolKit/Ratchet/AliceAxolotlParameters.m b/SessionProtocolKit/Signal/Ratchet/AliceAxolotlParameters.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/AliceAxolotlParameters.m
rename to SessionProtocolKit/Signal/Ratchet/AliceAxolotlParameters.m
diff --git a/SessionProtocolKit/Ratchet/AxolotlParameters.h b/SessionProtocolKit/Signal/Ratchet/AxolotlParameters.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/AxolotlParameters.h
rename to SessionProtocolKit/Signal/Ratchet/AxolotlParameters.h
diff --git a/SessionProtocolKit/Ratchet/BobAxolotlParameters.h b/SessionProtocolKit/Signal/Ratchet/BobAxolotlParameters.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/BobAxolotlParameters.h
rename to SessionProtocolKit/Signal/Ratchet/BobAxolotlParameters.h
diff --git a/SessionProtocolKit/Ratchet/BobAxolotlParameters.m b/SessionProtocolKit/Signal/Ratchet/BobAxolotlParameters.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/BobAxolotlParameters.m
rename to SessionProtocolKit/Signal/Ratchet/BobAxolotlParameters.m
diff --git a/SessionProtocolKit/Ratchet/Chain.h b/SessionProtocolKit/Signal/Ratchet/Chain.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/Chain.h
rename to SessionProtocolKit/Signal/Ratchet/Chain.h
diff --git a/SessionProtocolKit/Ratchet/ChainAndIndex.h b/SessionProtocolKit/Signal/Ratchet/ChainAndIndex.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/ChainAndIndex.h
rename to SessionProtocolKit/Signal/Ratchet/ChainAndIndex.h
diff --git a/SessionProtocolKit/Ratchet/ChainAndIndex.m b/SessionProtocolKit/Signal/Ratchet/ChainAndIndex.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/ChainAndIndex.m
rename to SessionProtocolKit/Signal/Ratchet/ChainAndIndex.m
diff --git a/SessionProtocolKit/Ratchet/ChainKey.h b/SessionProtocolKit/Signal/Ratchet/ChainKey.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/ChainKey.h
rename to SessionProtocolKit/Signal/Ratchet/ChainKey.h
diff --git a/SessionProtocolKit/Ratchet/ChainKey.m b/SessionProtocolKit/Signal/Ratchet/ChainKey.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/ChainKey.m
rename to SessionProtocolKit/Signal/Ratchet/ChainKey.m
diff --git a/SessionProtocolKit/Ratchet/MessageKeys.h b/SessionProtocolKit/Signal/Ratchet/MessageKeys.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/MessageKeys.h
rename to SessionProtocolKit/Signal/Ratchet/MessageKeys.h
diff --git a/SessionProtocolKit/Ratchet/MessageKeys.m b/SessionProtocolKit/Signal/Ratchet/MessageKeys.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/MessageKeys.m
rename to SessionProtocolKit/Signal/Ratchet/MessageKeys.m
diff --git a/SessionProtocolKit/Ratchet/RKCK.h b/SessionProtocolKit/Signal/Ratchet/RKCK.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/RKCK.h
rename to SessionProtocolKit/Signal/Ratchet/RKCK.h
diff --git a/SessionProtocolKit/Ratchet/RKCK.m b/SessionProtocolKit/Signal/Ratchet/RKCK.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/RKCK.m
rename to SessionProtocolKit/Signal/Ratchet/RKCK.m
diff --git a/SessionProtocolKit/Ratchet/RatchetingSession.h b/SessionProtocolKit/Signal/Ratchet/RatchetingSession.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/RatchetingSession.h
rename to SessionProtocolKit/Signal/Ratchet/RatchetingSession.h
diff --git a/SessionProtocolKit/Ratchet/RatchetingSession.m b/SessionProtocolKit/Signal/Ratchet/RatchetingSession.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/RatchetingSession.m
rename to SessionProtocolKit/Signal/Ratchet/RatchetingSession.m
diff --git a/SessionProtocolKit/Ratchet/ReceivingChain.h b/SessionProtocolKit/Signal/Ratchet/ReceivingChain.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/ReceivingChain.h
rename to SessionProtocolKit/Signal/Ratchet/ReceivingChain.h
diff --git a/SessionProtocolKit/Ratchet/ReceivingChain.m b/SessionProtocolKit/Signal/Ratchet/ReceivingChain.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/ReceivingChain.m
rename to SessionProtocolKit/Signal/Ratchet/ReceivingChain.m
diff --git a/SessionProtocolKit/Ratchet/RootKey.h b/SessionProtocolKit/Signal/Ratchet/RootKey.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/RootKey.h
rename to SessionProtocolKit/Signal/Ratchet/RootKey.h
diff --git a/SessionProtocolKit/Ratchet/RootKey.m b/SessionProtocolKit/Signal/Ratchet/RootKey.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/RootKey.m
rename to SessionProtocolKit/Signal/Ratchet/RootKey.m
diff --git a/SessionProtocolKit/Ratchet/SendingChain.h b/SessionProtocolKit/Signal/Ratchet/SendingChain.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/SendingChain.h
rename to SessionProtocolKit/Signal/Ratchet/SendingChain.h
diff --git a/SessionProtocolKit/Ratchet/SendingChain.m b/SessionProtocolKit/Signal/Ratchet/SendingChain.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/SendingChain.m
rename to SessionProtocolKit/Signal/Ratchet/SendingChain.m
diff --git a/SessionProtocolKit/Ratchet/TSDerivedSecrets.h b/SessionProtocolKit/Signal/Ratchet/TSDerivedSecrets.h
similarity index 100%
rename from SessionProtocolKit/Ratchet/TSDerivedSecrets.h
rename to SessionProtocolKit/Signal/Ratchet/TSDerivedSecrets.h
diff --git a/SessionProtocolKit/Ratchet/TSDerivedSecrets.m b/SessionProtocolKit/Signal/Ratchet/TSDerivedSecrets.m
similarity index 100%
rename from SessionProtocolKit/Ratchet/TSDerivedSecrets.m
rename to SessionProtocolKit/Signal/Ratchet/TSDerivedSecrets.m
diff --git a/SessionProtocolKit/SessionCipher.h b/SessionProtocolKit/Signal/SessionCipher.h
similarity index 100%
rename from SessionProtocolKit/SessionCipher.h
rename to SessionProtocolKit/Signal/SessionCipher.h
diff --git a/SessionProtocolKit/SessionCipher.m b/SessionProtocolKit/Signal/SessionCipher.m
similarity index 100%
rename from SessionProtocolKit/SessionCipher.m
rename to SessionProtocolKit/Signal/SessionCipher.m
diff --git a/SessionProtocolKit/Sessions/SessionBuilder.h b/SessionProtocolKit/Signal/Sessions/SessionBuilder.h
similarity index 100%
rename from SessionProtocolKit/Sessions/SessionBuilder.h
rename to SessionProtocolKit/Signal/Sessions/SessionBuilder.h
diff --git a/SessionProtocolKit/Sessions/SessionBuilder.m b/SessionProtocolKit/Signal/Sessions/SessionBuilder.m
similarity index 100%
rename from SessionProtocolKit/Sessions/SessionBuilder.m
rename to SessionProtocolKit/Signal/Sessions/SessionBuilder.m
diff --git a/SessionProtocolKit/Sessions/SessionRecord.h b/SessionProtocolKit/Signal/Sessions/SessionRecord.h
similarity index 100%
rename from SessionProtocolKit/Sessions/SessionRecord.h
rename to SessionProtocolKit/Signal/Sessions/SessionRecord.h
diff --git a/SessionProtocolKit/Sessions/SessionRecord.m b/SessionProtocolKit/Signal/Sessions/SessionRecord.m
similarity index 100%
rename from SessionProtocolKit/Sessions/SessionRecord.m
rename to SessionProtocolKit/Signal/Sessions/SessionRecord.m
diff --git a/SessionProtocolKit/Sessions/SessionState.h b/SessionProtocolKit/Signal/Sessions/SessionState.h
similarity index 100%
rename from SessionProtocolKit/Sessions/SessionState.h
rename to SessionProtocolKit/Signal/Sessions/SessionState.h
diff --git a/SessionProtocolKit/Sessions/SessionState.m b/SessionProtocolKit/Signal/Sessions/SessionState.m
similarity index 100%
rename from SessionProtocolKit/Sessions/SessionState.m
rename to SessionProtocolKit/Signal/Sessions/SessionState.m
diff --git a/SessionProtocolKit/State/AxolotlStore.h b/SessionProtocolKit/Signal/State/AxolotlStore.h
similarity index 100%
rename from SessionProtocolKit/State/AxolotlStore.h
rename to SessionProtocolKit/Signal/State/AxolotlStore.h
diff --git a/SessionProtocolKit/State/IdentityKeyStore.h b/SessionProtocolKit/Signal/State/IdentityKeyStore.h
similarity index 100%
rename from SessionProtocolKit/State/IdentityKeyStore.h
rename to SessionProtocolKit/Signal/State/IdentityKeyStore.h
diff --git a/SessionProtocolKit/State/PreKeyStore.h b/SessionProtocolKit/Signal/State/PreKeyStore.h
similarity index 100%
rename from SessionProtocolKit/State/PreKeyStore.h
rename to SessionProtocolKit/Signal/State/PreKeyStore.h
diff --git a/SessionProtocolKit/State/SessionStore.h b/SessionProtocolKit/Signal/State/SessionStore.h
similarity index 100%
rename from SessionProtocolKit/State/SessionStore.h
rename to SessionProtocolKit/Signal/State/SessionStore.h
diff --git a/SessionProtocolKit/State/SignedPreKeyStore.h b/SessionProtocolKit/Signal/State/SignedPreKeyStore.h
similarity index 100%
rename from SessionProtocolKit/State/SignedPreKeyStore.h
rename to SessionProtocolKit/Signal/State/SignedPreKeyStore.h
diff --git a/SessionProtocolKit/Utility/Cryptography.h b/SessionProtocolKit/Signal/Utility/Cryptography.h
similarity index 100%
rename from SessionProtocolKit/Utility/Cryptography.h
rename to SessionProtocolKit/Signal/Utility/Cryptography.h
diff --git a/SessionProtocolKit/Utility/Cryptography.m b/SessionProtocolKit/Signal/Utility/Cryptography.m
similarity index 100%
rename from SessionProtocolKit/Utility/Cryptography.m
rename to SessionProtocolKit/Signal/Utility/Cryptography.m
diff --git a/SessionProtocolKit/Utility/Data+OWS.swift b/SessionProtocolKit/Signal/Utility/Data+OWS.swift
similarity index 100%
rename from SessionProtocolKit/Utility/Data+OWS.swift
rename to SessionProtocolKit/Signal/Utility/Data+OWS.swift
diff --git a/SessionProtocolKit/Utility/Logger.swift b/SessionProtocolKit/Signal/Utility/Logger.swift
similarity index 100%
rename from SessionProtocolKit/Utility/Logger.swift
rename to SessionProtocolKit/Signal/Utility/Logger.swift
diff --git a/SessionProtocolKit/Utility/NSData+OWS.h b/SessionProtocolKit/Signal/Utility/NSData+OWS.h
similarity index 100%
rename from SessionProtocolKit/Utility/NSData+OWS.h
rename to SessionProtocolKit/Signal/Utility/NSData+OWS.h
diff --git a/SessionProtocolKit/Utility/NSData+OWS.m b/SessionProtocolKit/Signal/Utility/NSData+OWS.m
similarity index 100%
rename from SessionProtocolKit/Utility/NSData+OWS.m
rename to SessionProtocolKit/Signal/Utility/NSData+OWS.m
diff --git a/SessionProtocolKit/Utility/NSData+keyVersionByte.h b/SessionProtocolKit/Signal/Utility/NSData+keyVersionByte.h
similarity index 100%
rename from SessionProtocolKit/Utility/NSData+keyVersionByte.h
rename to SessionProtocolKit/Signal/Utility/NSData+keyVersionByte.h
diff --git a/SessionProtocolKit/Utility/NSData+keyVersionByte.m b/SessionProtocolKit/Signal/Utility/NSData+keyVersionByte.m
similarity index 100%
rename from SessionProtocolKit/Utility/NSData+keyVersionByte.m
rename to SessionProtocolKit/Signal/Utility/NSData+keyVersionByte.m
diff --git a/SessionProtocolKit/Utility/NSDate+OWS.h b/SessionProtocolKit/Signal/Utility/NSDate+OWS.h
similarity index 100%
rename from SessionProtocolKit/Utility/NSDate+OWS.h
rename to SessionProtocolKit/Signal/Utility/NSDate+OWS.h
diff --git a/SessionProtocolKit/Utility/NSDate+OWS.mm b/SessionProtocolKit/Signal/Utility/NSDate+OWS.mm
similarity index 100%
rename from SessionProtocolKit/Utility/NSDate+OWS.mm
rename to SessionProtocolKit/Signal/Utility/NSDate+OWS.mm
diff --git a/SessionProtocolKit/Utility/NSObject+OWS.h b/SessionProtocolKit/Signal/Utility/NSObject+OWS.h
similarity index 100%
rename from SessionProtocolKit/Utility/NSObject+OWS.h
rename to SessionProtocolKit/Signal/Utility/NSObject+OWS.h
diff --git a/SessionProtocolKit/Utility/NSObject+OWS.m b/SessionProtocolKit/Signal/Utility/NSObject+OWS.m
similarity index 100%
rename from SessionProtocolKit/Utility/NSObject+OWS.m
rename to SessionProtocolKit/Signal/Utility/NSObject+OWS.m
diff --git a/SessionProtocolKit/Utility/NSString+OWS.h b/SessionProtocolKit/Signal/Utility/NSString+OWS.h
similarity index 100%
rename from SessionProtocolKit/Utility/NSString+OWS.h
rename to SessionProtocolKit/Signal/Utility/NSString+OWS.h
diff --git a/SessionProtocolKit/Utility/NSString+OWS.m b/SessionProtocolKit/Signal/Utility/NSString+OWS.m
similarity index 100%
rename from SessionProtocolKit/Utility/NSString+OWS.m
rename to SessionProtocolKit/Signal/Utility/NSString+OWS.m
diff --git a/SessionProtocolKit/Utility/OWSAsserts.h b/SessionProtocolKit/Signal/Utility/OWSAsserts.h
similarity index 100%
rename from SessionProtocolKit/Utility/OWSAsserts.h
rename to SessionProtocolKit/Signal/Utility/OWSAsserts.h
diff --git a/SessionProtocolKit/Utility/OWSAsserts.m b/SessionProtocolKit/Signal/Utility/OWSAsserts.m
similarity index 100%
rename from SessionProtocolKit/Utility/OWSAsserts.m
rename to SessionProtocolKit/Signal/Utility/OWSAsserts.m
diff --git a/SessionProtocolKit/Utility/OWSDataParser.swift b/SessionProtocolKit/Signal/Utility/OWSDataParser.swift
similarity index 100%
rename from SessionProtocolKit/Utility/OWSDataParser.swift
rename to SessionProtocolKit/Signal/Utility/OWSDataParser.swift
diff --git a/SessionProtocolKit/Utility/OWSLogs.h b/SessionProtocolKit/Signal/Utility/OWSLogs.h
similarity index 100%
rename from SessionProtocolKit/Utility/OWSLogs.h
rename to SessionProtocolKit/Signal/Utility/OWSLogs.h
diff --git a/SessionProtocolKit/Utility/OWSLogs.m b/SessionProtocolKit/Signal/Utility/OWSLogs.m
similarity index 100%
rename from SessionProtocolKit/Utility/OWSLogs.m
rename to SessionProtocolKit/Signal/Utility/OWSLogs.m
diff --git a/SessionProtocolKit/Utility/OWSSwiftUtils.swift b/SessionProtocolKit/Signal/Utility/OWSSwiftUtils.swift
similarity index 100%
rename from SessionProtocolKit/Utility/OWSSwiftUtils.swift
rename to SessionProtocolKit/Signal/Utility/OWSSwiftUtils.swift
diff --git a/SessionProtocolKit/Utility/Randomness.h b/SessionProtocolKit/Signal/Utility/Randomness.h
similarity index 100%
rename from SessionProtocolKit/Utility/Randomness.h
rename to SessionProtocolKit/Signal/Utility/Randomness.h
diff --git a/SessionProtocolKit/Utility/Randomness.m b/SessionProtocolKit/Signal/Utility/Randomness.m
similarity index 100%
rename from SessionProtocolKit/Utility/Randomness.m
rename to SessionProtocolKit/Signal/Utility/Randomness.m
diff --git a/SessionProtocolKit/Utility/SCKExceptionWrapper.h b/SessionProtocolKit/Signal/Utility/SCKExceptionWrapper.h
similarity index 100%
rename from SessionProtocolKit/Utility/SCKExceptionWrapper.h
rename to SessionProtocolKit/Signal/Utility/SCKExceptionWrapper.h
diff --git a/SessionProtocolKit/Utility/SCKExceptionWrapper.m b/SessionProtocolKit/Signal/Utility/SCKExceptionWrapper.m
similarity index 100%
rename from SessionProtocolKit/Utility/SCKExceptionWrapper.m
rename to SessionProtocolKit/Signal/Utility/SCKExceptionWrapper.m
diff --git a/SessionProtocolKit/Utility/SerializationUtilities.h b/SessionProtocolKit/Signal/Utility/SerializationUtilities.h
similarity index 100%
rename from SessionProtocolKit/Utility/SerializationUtilities.h
rename to SessionProtocolKit/Signal/Utility/SerializationUtilities.h
diff --git a/SessionProtocolKit/Utility/SerializationUtilities.m b/SessionProtocolKit/Signal/Utility/SerializationUtilities.m
similarity index 100%
rename from SessionProtocolKit/Utility/SerializationUtilities.m
rename to SessionProtocolKit/Signal/Utility/SerializationUtilities.m
diff --git a/SessionProtocolKit/Utility/String+OWS.swift b/SessionProtocolKit/Signal/Utility/String+OWS.swift
similarity index 100%
rename from SessionProtocolKit/Utility/String+OWS.swift
rename to SessionProtocolKit/Signal/Utility/String+OWS.swift
diff --git a/SessionProtocolKit/Utility/Threading.h b/SessionProtocolKit/Signal/Utility/Threading.h
similarity index 100%
rename from SessionProtocolKit/Utility/Threading.h
rename to SessionProtocolKit/Signal/Utility/Threading.h
diff --git a/SessionProtocolKit/Utility/Threading.m b/SessionProtocolKit/Signal/Utility/Threading.m
similarity index 100%
rename from SessionProtocolKit/Utility/Threading.m
rename to SessionProtocolKit/Signal/Utility/Threading.m
diff --git a/SessionProtocolKit/Utility/iOSVersions.h b/SessionProtocolKit/Signal/Utility/iOSVersions.h
similarity index 100%
rename from SessionProtocolKit/Utility/iOSVersions.h
rename to SessionProtocolKit/Signal/Utility/iOSVersions.h
diff --git a/SessionSnodeKit/Utilities/Data+Utilities.swift b/SessionSnodeKit/Utilities/Data+Utilities.swift
index 565ead5ce..d8d72aa9f 100644
--- a/SessionSnodeKit/Utilities/Data+Utilities.swift
+++ b/SessionSnodeKit/Utilities/Data+Utilities.swift
@@ -2,15 +2,6 @@ import Foundation
 
 internal extension Data {
 
-    /// Returns `size` bytes of random data generated using the default secure random number generator. See
-    /// [SecRandomCopyBytes](https://developer.apple.com/documentation/security/1399291-secrandomcopybytes) for more information.
-    static func getSecureRandomData(ofSize size: UInt) -> Data? {
-        var data = Data(count: Int(size))
-        let result = data.withUnsafeMutableBytes { SecRandomCopyBytes(kSecRandomDefault, Int(size), $0.baseAddress!) }
-        guard result == errSecSuccess else { return nil }
-        return data
-    }
-
     init(from inputStream: InputStream) throws {
         self.init()
         inputStream.open()
diff --git a/SessionUtilities/Array+Description.swift b/SessionUtilities/Array+Description.swift
index 6ac99240a..3d58476dc 100644
--- a/SessionUtilities/Array+Description.swift
+++ b/SessionUtilities/Array+Description.swift
@@ -1,7 +1,7 @@
 
 public extension Array where Element : CustomStringConvertible {
 
-    var prettifiedDescription: String {
+    public var prettifiedDescription: String {
         return "[ " + map { $0.description }.joined(separator: ", ") + " ]"
     }
 }
diff --git a/SessionUtilities/Data+SecureRandom.swift b/SessionUtilities/Data+SecureRandom.swift
new file mode 100644
index 000000000..1ca9749f8
--- /dev/null
+++ b/SessionUtilities/Data+SecureRandom.swift
@@ -0,0 +1,13 @@
+import Foundation
+
+public extension Data {
+
+    /// Returns `size` bytes of random data generated using the default secure random number generator. See
+    /// [SecRandomCopyBytes](https://developer.apple.com/documentation/security/1399291-secrandomcopybytes) for more information.
+    static func getSecureRandomData(ofSize size: UInt) -> Data? {
+        var data = Data(count: Int(size))
+        let result = data.withUnsafeMutableBytes { SecRandomCopyBytes(kSecRandomDefault, Int(size), $0.baseAddress!) }
+        guard result == errSecSuccess else { return nil }
+        return data
+    }
+}
diff --git a/SessionUtilities/String+Trimming.swift b/SessionUtilities/String+Trimming.swift
new file mode 100644
index 000000000..5e3f8b8cf
--- /dev/null
+++ b/SessionUtilities/String+Trimming.swift
@@ -0,0 +1,9 @@
+
+public extension String {
+
+    public func removing05PrefixIfNeeded() -> String {
+        var result = self
+        if result.count == 66 && result.hasPrefix("05") { result.removeFirst(2) }
+        return result
+    }
+}
diff --git a/Signal.xcodeproj/project.pbxproj b/Signal.xcodeproj/project.pbxproj
index d07f4420d..06c7c0fd2 100644
--- a/Signal.xcodeproj/project.pbxproj
+++ b/Signal.xcodeproj/project.pbxproj
@@ -732,6 +732,15 @@
 		C3C2AA082553B9C400C340D1 /* NSString+OWS.m in Sources */ = {isa = PBXBuildFile; fileRef = C3C2A9ED2553B9C400C340D1 /* NSString+OWS.m */; };
 		C3C2AA092553B9C400C340D1 /* NSObject+OWS.h in Headers */ = {isa = PBXBuildFile; fileRef = C3C2A9EE2553B9C400C340D1 /* NSObject+OWS.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		C3C2AAC82553C25300C340D1 /* SessionProtocolKit.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C3C2A8622553B41A00C340D1 /* SessionProtocolKit.framework */; };
+		C3C2AB642553C5FF00C340D1 /* SharedSenderKeys.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C2AB632553C5FF00C340D1 /* SharedSenderKeys.swift */; };
+		C3C2ABD22553C6C900C340D1 /* Data+SecureRandom.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C2ABD12553C6C900C340D1 /* Data+SecureRandom.swift */; };
+		C3C2ABE42553C74400C340D1 /* ClosedGroupRatchet.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C2ABE32553C74400C340D1 /* ClosedGroupRatchet.swift */; };
+		C3C2ABEE2553C76900C340D1 /* ClosedGroupSenderKey.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C2ABED2553C76900C340D1 /* ClosedGroupSenderKey.swift */; };
+		C3C2ABF82553C8A300C340D1 /* Storage.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C2ABF72553C8A300C340D1 /* Storage.swift */; };
+		C3C2AC0A2553C9A100C340D1 /* Configuration.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C2AC092553C9A100C340D1 /* Configuration.swift */; };
+		C3C2AC1C2553CADF00C340D1 /* SharedSenderKeysDelegate.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C2AC1B2553CADF00C340D1 /* SharedSenderKeysDelegate.swift */; };
+		C3C2AC2E2553CBEB00C340D1 /* String+Trimming.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C2AC2D2553CBEB00C340D1 /* String+Trimming.swift */; };
+		C3C2AC372553CCE600C340D1 /* SessionUtilities.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = C3C2A679255388CC00C340D1 /* SessionUtilities.framework */; };
 		C3C3CF8924D8EED300E1CCE7 /* TextView.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3C3CF8824D8EED300E1CCE7 /* TextView.swift */; };
 		C3D0972B2510499C00F6E3E4 /* BackgroundPoller.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3D0972A2510499C00F6E3E4 /* BackgroundPoller.swift */; };
 		C3DAB3242480CB2B00725F25 /* SRCopyableLabel.swift in Sources */ = {isa = PBXBuildFile; fileRef = C3DAB3232480CB2A00725F25 /* SRCopyableLabel.swift */; };
@@ -1619,15 +1628,15 @@
 		C3C2A8642553B41A00C340D1 /* SessionProtocolKit.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = SessionProtocolKit.h; sourceTree = "<group>"; };
 		C3C2A8652553B41A00C340D1 /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
 		C3C2A8872553B4CC00C340D1 /* AxolotlExceptions.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = AxolotlExceptions.h; sourceTree = "<group>"; };
-		C3C2A8932553B4F500C340D1 /* PreKeyWhisperMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = PreKeyWhisperMessage.h; path = SessionProtocolKit/CipherMessage/PreKeyWhisperMessage.h; sourceTree = SOURCE_ROOT; };
-		C3C2A8942553B4F500C340D1 /* ClosedGroupCiphertextMessage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = ClosedGroupCiphertextMessage.m; path = SessionProtocolKit/CipherMessage/ClosedGroupCiphertextMessage.m; sourceTree = SOURCE_ROOT; };
-		C3C2A8952553B4F500C340D1 /* WhisperMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = WhisperMessage.h; path = SessionProtocolKit/CipherMessage/WhisperMessage.h; sourceTree = SOURCE_ROOT; };
-		C3C2A8962553B4F500C340D1 /* ClosedGroupCiphertextMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ClosedGroupCiphertextMessage.h; path = SessionProtocolKit/CipherMessage/ClosedGroupCiphertextMessage.h; sourceTree = SOURCE_ROOT; };
-		C3C2A8972553B4F500C340D1 /* PreKeyWhisperMessage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = PreKeyWhisperMessage.m; path = SessionProtocolKit/CipherMessage/PreKeyWhisperMessage.m; sourceTree = SOURCE_ROOT; };
-		C3C2A8982553B4F600C340D1 /* WhisperMessage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = WhisperMessage.m; path = SessionProtocolKit/CipherMessage/WhisperMessage.m; sourceTree = SOURCE_ROOT; };
-		C3C2A8992553B4F600C340D1 /* CipherMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = CipherMessage.h; path = SessionProtocolKit/CipherMessage/CipherMessage.h; sourceTree = SOURCE_ROOT; };
-		C3C2A89A2553B4F600C340D1 /* FallbackMessage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = FallbackMessage.m; path = SessionProtocolKit/CipherMessage/FallbackMessage.m; sourceTree = SOURCE_ROOT; };
-		C3C2A89B2553B4F600C340D1 /* FallbackMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = FallbackMessage.h; path = SessionProtocolKit/CipherMessage/FallbackMessage.h; sourceTree = SOURCE_ROOT; };
+		C3C2A8932553B4F500C340D1 /* PreKeyWhisperMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = PreKeyWhisperMessage.h; path = SessionProtocolKit/Signal/CipherMessage/PreKeyWhisperMessage.h; sourceTree = SOURCE_ROOT; };
+		C3C2A8942553B4F500C340D1 /* ClosedGroupCiphertextMessage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = ClosedGroupCiphertextMessage.m; path = SessionProtocolKit/Signal/CipherMessage/ClosedGroupCiphertextMessage.m; sourceTree = SOURCE_ROOT; };
+		C3C2A8952553B4F500C340D1 /* WhisperMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = WhisperMessage.h; path = SessionProtocolKit/Signal/CipherMessage/WhisperMessage.h; sourceTree = SOURCE_ROOT; };
+		C3C2A8962553B4F500C340D1 /* ClosedGroupCiphertextMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = ClosedGroupCiphertextMessage.h; path = SessionProtocolKit/Signal/CipherMessage/ClosedGroupCiphertextMessage.h; sourceTree = SOURCE_ROOT; };
+		C3C2A8972553B4F500C340D1 /* PreKeyWhisperMessage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = PreKeyWhisperMessage.m; path = SessionProtocolKit/Signal/CipherMessage/PreKeyWhisperMessage.m; sourceTree = SOURCE_ROOT; };
+		C3C2A8982553B4F600C340D1 /* WhisperMessage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = WhisperMessage.m; path = SessionProtocolKit/Signal/CipherMessage/WhisperMessage.m; sourceTree = SOURCE_ROOT; };
+		C3C2A8992553B4F600C340D1 /* CipherMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = CipherMessage.h; path = SessionProtocolKit/Signal/CipherMessage/CipherMessage.h; sourceTree = SOURCE_ROOT; };
+		C3C2A89A2553B4F600C340D1 /* FallbackMessage.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = FallbackMessage.m; path = SessionProtocolKit/Signal/CipherMessage/FallbackMessage.m; sourceTree = SOURCE_ROOT; };
+		C3C2A89B2553B4F600C340D1 /* FallbackMessage.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = FallbackMessage.h; path = SessionProtocolKit/Signal/CipherMessage/FallbackMessage.h; sourceTree = SOURCE_ROOT; };
 		C3C2A8B52553B53700C340D1 /* Constants.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = Constants.h; sourceTree = "<group>"; };
 		C3C2A8C02553B55600C340D1 /* AES-CBC.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = "AES-CBC.h"; path = "Crypto/AES-CBC.h"; sourceTree = "<group>"; };
 		C3C2A8C12553B55600C340D1 /* AES-CBC.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = "AES-CBC.m"; path = "Crypto/AES-CBC.m"; sourceTree = "<group>"; };
@@ -1706,6 +1715,14 @@
 		C3C2A9EC2553B9C400C340D1 /* Cryptography.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = Cryptography.m; path = Utility/Cryptography.m; sourceTree = "<group>"; };
 		C3C2A9ED2553B9C400C340D1 /* NSString+OWS.m */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.objc; name = "NSString+OWS.m"; path = "Utility/NSString+OWS.m"; sourceTree = "<group>"; };
 		C3C2A9EE2553B9C400C340D1 /* NSObject+OWS.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = "NSObject+OWS.h"; path = "Utility/NSObject+OWS.h"; sourceTree = "<group>"; };
+		C3C2AB632553C5FF00C340D1 /* SharedSenderKeys.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SharedSenderKeys.swift; sourceTree = "<group>"; };
+		C3C2ABD12553C6C900C340D1 /* Data+SecureRandom.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "Data+SecureRandom.swift"; sourceTree = "<group>"; };
+		C3C2ABE32553C74400C340D1 /* ClosedGroupRatchet.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ClosedGroupRatchet.swift; sourceTree = "<group>"; };
+		C3C2ABED2553C76900C340D1 /* ClosedGroupSenderKey.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = ClosedGroupSenderKey.swift; sourceTree = "<group>"; };
+		C3C2ABF72553C8A300C340D1 /* Storage.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Storage.swift; sourceTree = "<group>"; };
+		C3C2AC092553C9A100C340D1 /* Configuration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = Configuration.swift; sourceTree = "<group>"; };
+		C3C2AC1B2553CADF00C340D1 /* SharedSenderKeysDelegate.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SharedSenderKeysDelegate.swift; sourceTree = "<group>"; };
+		C3C2AC2D2553CBEB00C340D1 /* String+Trimming.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = "String+Trimming.swift"; sourceTree = "<group>"; };
 		C3C3CF8824D8EED300E1CCE7 /* TextView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TextView.swift; sourceTree = "<group>"; };
 		C3D0972A2510499C00F6E3E4 /* BackgroundPoller.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BackgroundPoller.swift; sourceTree = "<group>"; };
 		C3DAB3232480CB2A00725F25 /* SRCopyableLabel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = SRCopyableLabel.swift; sourceTree = "<group>"; };
@@ -1802,6 +1819,7 @@
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				C3C2AC372553CCE600C340D1 /* SessionUtilities.framework in Frameworks */,
 				A33A4BA9D050805FE156E3ED /* Pods_SessionProtocolKit.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
@@ -3204,11 +3222,13 @@
 			children = (
 				C3C2A68B255388D500C340D1 /* Meta */,
 				C3C2A5D12553860800C340D1 /* Array+Description.swift */,
+				C3C2ABD12553C6C900C340D1 /* Data+SecureRandom.swift */,
 				C3C2A5D52553860A00C340D1 /* Dictionary+Description.swift */,
 				C3C2A5BC255385EE00C340D1 /* HTTP.swift */,
 				C3C2A5D92553860B00C340D1 /* JSON.swift */,
 				C3C2A5CE2553860700C340D1 /* Logging.swift */,
 				C3C2A5D62553860B00C340D1 /* Promise+Retrying.swift */,
+				C3C2AC2D2553CBEB00C340D1 /* String+Trimming.swift */,
 			);
 			path = SessionUtilities;
 			sourceTree = "<group>";
@@ -3266,19 +3286,10 @@
 		C3C2A8632553B41A00C340D1 /* SessionProtocolKit */ = {
 			isa = PBXGroup;
 			children = (
-				C3C2A8872553B4CC00C340D1 /* AxolotlExceptions.h */,
-				C3C2A8922553B4E400C340D1 /* CipherMessage */,
-				C3C2A8B52553B53700C340D1 /* Constants.h */,
-				C3C2A8BF2553B54600C340D1 /* Crypto */,
 				C3C2A8762553B42C00C340D1 /* Meta */,
-				C3C2A8CD2553B56400C340D1 /* Prekeys */,
-				C3C2A8E32553B58B00C340D1 /* Protos */,
-				C3C2A8F02553B5A100C340D1 /* Ratchet */,
-				C3C2A9292553B5BD00C340D1 /* SessionCipher.h */,
-				C3C2A92A2553B5BE00C340D1 /* SessionCipher.m */,
-				C3C2A9352553B5C300C340D1 /* Sessions */,
-				C3C2A9562553B5F600C340D1 /* State */,
-				C3C2A9692553B62B00C340D1 /* Utility */,
+				C3C2AC092553C9A100C340D1 /* Configuration.swift */,
+				C3C2AB622553C5D400C340D1 /* Shared Sender Keys */,
+				C3C2AB492553C4A800C340D1 /* Signal */,
 			);
 			path = SessionProtocolKit;
 			sourceTree = "<group>";
@@ -3432,6 +3443,37 @@
 			name = Utility;
 			sourceTree = "<group>";
 		};
+		C3C2AB492553C4A800C340D1 /* Signal */ = {
+			isa = PBXGroup;
+			children = (
+				C3C2A8872553B4CC00C340D1 /* AxolotlExceptions.h */,
+				C3C2A8922553B4E400C340D1 /* CipherMessage */,
+				C3C2A8B52553B53700C340D1 /* Constants.h */,
+				C3C2A8BF2553B54600C340D1 /* Crypto */,
+				C3C2A8CD2553B56400C340D1 /* Prekeys */,
+				C3C2A8E32553B58B00C340D1 /* Protos */,
+				C3C2A8F02553B5A100C340D1 /* Ratchet */,
+				C3C2A9292553B5BD00C340D1 /* SessionCipher.h */,
+				C3C2A92A2553B5BE00C340D1 /* SessionCipher.m */,
+				C3C2A9352553B5C300C340D1 /* Sessions */,
+				C3C2A9562553B5F600C340D1 /* State */,
+				C3C2A9692553B62B00C340D1 /* Utility */,
+			);
+			path = Signal;
+			sourceTree = "<group>";
+		};
+		C3C2AB622553C5D400C340D1 /* Shared Sender Keys */ = {
+			isa = PBXGroup;
+			children = (
+				C3C2ABE32553C74400C340D1 /* ClosedGroupRatchet.swift */,
+				C3C2ABED2553C76900C340D1 /* ClosedGroupSenderKey.swift */,
+				C3C2AB632553C5FF00C340D1 /* SharedSenderKeys.swift */,
+				C3C2AC1B2553CADF00C340D1 /* SharedSenderKeysDelegate.swift */,
+				C3C2ABF72553C8A300C340D1 /* Storage.swift */,
+			);
+			path = "Shared Sender Keys";
+			sourceTree = "<group>";
+		};
 		D221A07E169C9E5E00537ABF = {
 			isa = PBXGroup;
 			children = (
@@ -3947,6 +3989,7 @@
 					C3C2A678255388CC00C340D1 = {
 						CreatedOnToolsVersion = 12.1;
 						DevelopmentTeam = SUQ8J2PCT7;
+						LastSwiftMigration = 1210;
 						ProvisioningStyle = Automatic;
 					};
 					C3C2A6EF25539DE700C340D1 = {
@@ -4754,6 +4797,8 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				C3C2ABD22553C6C900C340D1 /* Data+SecureRandom.swift in Sources */,
+				C3C2AC2E2553CBEB00C340D1 /* String+Trimming.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -4779,6 +4824,7 @@
 				C3C2A91B2553B5B200C340D1 /* BobAxolotlParameters.m in Sources */,
 				C3C2A8D82553B57C00C340D1 /* PreKeyRecord.m in Sources */,
 				C3C2A9712553B63C00C340D1 /* SerializationUtilities.m in Sources */,
+				C3C2ABEE2553C76900C340D1 /* ClosedGroupSenderKey.swift in Sources */,
 				C3C2A9172553B5B200C340D1 /* RootKey.m in Sources */,
 				C3C2A9112553B5B200C340D1 /* ChainKey.m in Sources */,
 				C3C2A8C32553B55600C340D1 /* AES-CBC.m in Sources */,
@@ -4790,6 +4836,7 @@
 				C3C2A8A02553B4F600C340D1 /* PreKeyWhisperMessage.m in Sources */,
 				C3C2A93F2553B5D700C340D1 /* SessionState.m in Sources */,
 				C3C2A9F02553B9C400C340D1 /* OWSAsserts.m in Sources */,
+				C3C2ABF82553C8A300C340D1 /* Storage.swift in Sources */,
 				C3C2A9F72553B9C400C340D1 /* NSData+OWS.m in Sources */,
 				C3C2A90D2553B5B200C340D1 /* RKCK.m in Sources */,
 				C3C2A8E72553B59B00C340D1 /* SPKProto.swift in Sources */,
@@ -4801,16 +4848,20 @@
 				C3C2A8A32553B4F600C340D1 /* FallbackMessage.m in Sources */,
 				C3C2AA072553B9C400C340D1 /* Cryptography.m in Sources */,
 				C3C2A9F52553B9C400C340D1 /* NSDate+OWS.mm in Sources */,
+				C3C2ABE42553C74400C340D1 /* ClosedGroupRatchet.swift in Sources */,
 				C3C2A93E2553B5D700C340D1 /* SessionRecord.m in Sources */,
 				C3C2AA052553B9C400C340D1 /* SCKExceptionWrapper.m in Sources */,
 				C3C2A8D62553B57C00C340D1 /* PreKeyBundle.m in Sources */,
 				C3C2A9F62553B9C400C340D1 /* Data+OWS.swift in Sources */,
 				C3C2A89D2553B4F600C340D1 /* ClosedGroupCiphertextMessage.m in Sources */,
 				C3C2A9FB2553B9C400C340D1 /* Logger.swift in Sources */,
+				C3C2AC0A2553C9A100C340D1 /* Configuration.swift in Sources */,
 				C3C2A96E2553B63C00C340D1 /* NSData+keyVersionByte.m in Sources */,
 				C3C2A8E62553B59B00C340D1 /* WhisperTextProtocol.pb.swift in Sources */,
+				C3C2AB642553C5FF00C340D1 /* SharedSenderKeys.swift in Sources */,
 				C3C2A9102553B5B200C340D1 /* AliceAxolotlParameters.m in Sources */,
 				C3C2A9FA2553B9C400C340D1 /* OWSSwiftUtils.swift in Sources */,
+				C3C2AC1C2553CADF00C340D1 /* SharedSenderKeysDelegate.swift in Sources */,
 				C3C2A92C2553B5BE00C340D1 /* SessionCipher.m in Sources */,
 				C3C2A8D42553B57C00C340D1 /* SignedPrekeyRecord.m in Sources */,
 				C3C2A8A12553B4F600C340D1 /* WhisperMessage.m in Sources */,
@@ -5698,6 +5749,7 @@
 				CLANG_ANALYZER_NUMBER_OBJECT_CONVERSION = YES_AGGRESSIVE;
 				CLANG_CXX_LANGUAGE_STANDARD = "gnu++14";
 				CLANG_CXX_LIBRARY = "libc++";
+				CLANG_ENABLE_MODULES = YES;
 				CLANG_ENABLE_OBJC_WEAK = YES;
 				CLANG_WARN_BOOL_CONVERSION = YES;
 				CLANG_WARN_DIRECT_OBJC_ISA_USAGE = YES_ERROR;