diff --git a/Sources/App/Message+Extensions.swift b/Sources/App/Message+Extensions.swift
new file mode 100644
index 0000000..4bc58a1
--- /dev/null
+++ b/Sources/App/Message+Extensions.swift
@@ -0,0 +1,33 @@
+import Foundation
+import Crypto
+
+extension Message {
+
+    static var length: Int {
+        SHA256.byteCount + Content.length
+    }
+
+    init<T: Sequence>(decodeFrom data: T) where T.Element == UInt8 {
+        let count = SHA256.byteCount
+        self.mac = Data(data.prefix(count))
+        self.content = .init(decodeFrom: Array(data.dropFirst(count)))
+    }
+
+    func isValid(using key: SymmetricKey) -> Bool {
+         HMAC<SHA256>.isValidAuthenticationCode(mac, authenticating: content.encoded, using: key)
+    }
+}
+
+extension Message.Content {
+
+    func authenticate(using key: SymmetricKey) -> Message {
+        let mac = HMAC<SHA256>.authenticationCode(for: encoded, using: key)
+        return .init(mac: Data(mac.map { $0 }), content: self)
+    }
+
+    func authenticateAndSerialize(using key: SymmetricKey) -> Data {
+        let encoded = self.encoded
+        let mac = HMAC<SHA256>.authenticationCode(for: encoded, using: key)
+        return Data(mac.map { $0 }) + encoded
+    }
+}
diff --git a/Sources/App/Message.swift b/Sources/App/Message.swift
index 0c6083c..6891833 100644
--- a/Sources/App/Message.swift
+++ b/Sources/App/Message.swift
@@ -1,13 +1,8 @@
 import Foundation
-import CryptoKit
 import NIOCore
 
 struct Message: Equatable, Hashable {
 
-    static var length: Int {
-        SHA256Digest.byteCount + Content.length
-    }
-
     struct Content: Equatable, Hashable {
 
         let time: UInt32
@@ -28,17 +23,6 @@ struct Message: Equatable, Hashable {
             MemoryLayout<UInt32>.size * 2
         }
 
-        func authenticate(using key: SymmetricKey) -> Message {
-            let mac = HMAC<SHA256>.authenticationCode(for: encoded, using: key)
-            return .init(mac: Data(mac.map { $0 }), content: self)
-        }
-
-        func authenticateAndSerialize(using key: SymmetricKey) -> Data {
-            let encoded = self.encoded
-            let mac = HMAC<SHA256>.authenticationCode(for: encoded, using: key)
-            return Data(mac.map { $0 }) + encoded
-        }
-
         var encoded: Data {
             time.encoded + id.encoded
         }
@@ -64,16 +48,6 @@ struct Message: Equatable, Hashable {
         self.init(decodeFrom: data)
     }
 
-    private init<T: Sequence>(decodeFrom data: T) where T.Element == UInt8 {
-        let count = SHA256Digest.byteCount
-        self.mac = Data(data.prefix(count))
-        self.content = .init(decodeFrom: Array(data.dropFirst(count)))
-    }
-
-    func isValid(using key: SymmetricKey) -> Bool {
-         HMAC<SHA256>.isValidAuthenticationCode(mac, authenticating: content.encoded, using: key)
-    }
-
     var encoded: Data {
         mac + content.encoded
     }