diff --git a/src/Message.cpp b/src/Message.cpp
new file mode 100644
index 0000000000..609fd2e5b3
--- /dev/null
+++ b/src/Message.cpp
@@ -0,0 +1,330 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2015. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "Message.h"
+
+#include "WireDecoder.h"
+#include "WireEncoder.h"
+
+static constexpr unsigned long kClearAllMagic = 0xD06CB27Aul;
+
+using namespace ntimpl;
+
+bool Message::Read(WireDecoder& decoder,
+                   NT_Type (*get_entry_type)(unsigned int id), Message* msg) {
+  unsigned int msg_type;
+  if (!decoder.Read8(&msg_type)) return false;
+  switch (msg_type) {
+    case kKeepAlive:
+      *msg = KeepAlive();
+      break;
+    case kClientHello: {
+      unsigned int proto_rev;
+      if (!decoder.Read16(&proto_rev)) return false;
+      StringValue self_id;
+      // This intentionally uses the provided proto_rev instead of
+      // decoder.proto_rev().
+      if (proto_rev >= 0x0300u) {
+        if (!decoder.ReadString(&self_id)) return false;
+      }
+      *msg = Message(kClientHello);
+      msg->m_str = std::move(self_id);
+      msg->m_id = proto_rev;
+      break;
+    }
+    case kProtoUnsup: {
+      unsigned int proto_rev;
+      if (!decoder.Read16(&proto_rev)) return false;
+      *msg = ProtoUnsup();
+      msg->m_id = proto_rev;
+      break;
+    }
+    case kServerHelloDone:
+      if (decoder.proto_rev() < 0x0300u) {
+        decoder.set_error("received SERVER_HELLO_DONE in protocol < 3.0");
+        return false;
+      }
+      *msg = ServerHelloDone();
+      break;
+    case kClientHelloDone:
+      if (decoder.proto_rev() < 0x0300u) {
+        decoder.set_error("received CLIENT_HELLO_DONE in protocol < 3.0");
+        return false;
+      }
+      *msg = ClientHelloDone();
+      break;
+    case kEntryAssign: {
+      StringValue name;
+      if (!decoder.ReadString(&name)) return false;
+      NT_Type type;
+      if (!decoder.ReadType(&type)) return false;
+      unsigned int id, seq_num;
+      if (!decoder.Read16(&id)) return false;
+      if (!decoder.Read16(&seq_num)) return false;
+      unsigned int flags = 0;
+      if (decoder.proto_rev() >= 0x0300u) {
+        if (!decoder.Read8(&flags)) return false;
+      }
+      Value value;
+      if (!decoder.ReadValue(type, &value)) return false;
+      *msg = Message(kEntryAssign);
+      msg->m_str = std::move(name);
+      msg->m_value = std::make_shared<Value>(std::move(value));
+      msg->m_id = id;
+      msg->m_flags = flags;
+      msg->m_seq_num_uid = seq_num;
+      break;
+    }
+    case kEntryUpdate: {
+      unsigned int id, seq_num;
+      if (!decoder.Read16(&id)) return false;
+      if (!decoder.Read16(&seq_num)) return false;
+      NT_Type type;
+      if (decoder.proto_rev() >= 0x0300u) {
+        unsigned int itype;
+        if (!decoder.Read8(&itype)) return false;
+        type = static_cast<NT_Type>(itype);
+      } else
+        type = get_entry_type(id);
+      Value value;
+      if (!decoder.ReadValue(type, &value)) return false;
+      *msg = Message(kEntryUpdate);
+      msg->m_value = std::make_shared<Value>(std::move(value));
+      msg->m_id = id;
+      msg->m_seq_num_uid = seq_num;
+      break;
+    }
+    case kFlagsUpdate: {
+      if (decoder.proto_rev() < 0x0300u) {
+        decoder.set_error("received FLAGS_UPDATE in protocol < 3.0");
+        return false;
+      }
+      unsigned int id, flags;
+      if (!decoder.Read16(&id)) return false;
+      if (!decoder.Read8(&flags)) return false;
+      *msg = FlagsUpdate(id, flags);
+      break;
+    }
+    case kEntryDelete: {
+      if (decoder.proto_rev() < 0x0300u) {
+        decoder.set_error("received ENTRY_DELETE in protocol < 3.0");
+        return false;
+      }
+      unsigned int id;
+      if (!decoder.Read16(&id)) return false;
+      *msg = EntryDelete(id);
+      break;
+    }
+    case kClearEntries: {
+      if (decoder.proto_rev() < 0x0300u) {
+        decoder.set_error("received CLEAR_ENTRIES in protocol < 3.0");
+        return false;
+      }
+      unsigned long magic;
+      if (!decoder.Read32(&magic)) return false;
+      if (magic != kClearAllMagic) {
+        decoder.set_error(
+            "received incorrect CLEAR_ENTRIES magic value, ignoring");
+        return true;
+      }
+      *msg = ClearEntries();
+      break;
+    }
+    case kExecuteRpc: {
+      if (decoder.proto_rev() < 0x0300u) {
+        decoder.set_error("received EXECUTE_RPC in protocol < 3.0");
+        return false;
+      }
+      unsigned int id, uid;
+      if (!decoder.Read16(&id)) return false;
+      if (!decoder.Read16(&uid)) return false;
+      unsigned long size;
+      if (!decoder.ReadUleb128(&size)) return false;
+      const char* params;
+      if (!decoder.Read(&params, size)) return false;
+      *msg = ExecuteRpc(id, uid, llvm::StringRef(params, size));
+      break;
+    }
+    case kRpcResponse: {
+      if (decoder.proto_rev() < 0x0300u) {
+        decoder.set_error("received RPC_RESPONSE in protocol < 3.0");
+        return false;
+      }
+      unsigned int id, uid;
+      if (!decoder.Read16(&id)) return false;
+      if (!decoder.Read16(&uid)) return false;
+      unsigned long size;
+      if (!decoder.ReadUleb128(&size)) return false;
+      const char* results;
+      if (!decoder.Read(&results, size)) return false;
+      *msg = RpcResponse(id, uid, llvm::StringRef(results, size));
+      break;
+    }
+    default:
+      decoder.set_error("unrecognized message type");
+      return false;
+  }
+  return true;
+}
+
+Message Message::ClientHello(llvm::StringRef self_id) {
+  Message msg(kClientHello);
+  msg.m_str = StringValue(self_id);
+  return msg;
+}
+
+Message Message::ServerHello(unsigned int flags, llvm::StringRef self_id) {
+  Message msg(kServerHello);
+  msg.m_str = StringValue(self_id);
+  msg.m_flags = flags;
+  return msg;
+}
+
+Message Message::EntryAssign(llvm::StringRef name, unsigned int id,
+                             unsigned int seq_num, std::shared_ptr<Value> value,
+                             unsigned int flags) {
+  Message msg(kEntryAssign);
+  msg.m_str = StringValue(name);
+  msg.m_value = value;
+  msg.m_id = id;
+  msg.m_flags = flags;
+  msg.m_seq_num_uid = seq_num;
+  return msg;
+}
+
+Message Message::EntryUpdate(unsigned int id, unsigned int seq_num,
+                             std::shared_ptr<Value> value) {
+  Message msg(kEntryUpdate);
+  msg.m_value = value;
+  msg.m_id = id;
+  msg.m_seq_num_uid = seq_num;
+  return msg;
+}
+
+Message Message::FlagsUpdate(unsigned int id, unsigned int flags) {
+  Message msg(kFlagsUpdate);
+  msg.m_id = id;
+  msg.m_flags = flags;
+  return msg;
+}
+
+Message Message::EntryDelete(unsigned int id) {
+  Message msg(kEntryDelete);
+  msg.m_id = id;
+  return msg;
+}
+
+Message Message::ExecuteRpc(unsigned int id, unsigned int uid,
+                            llvm::ArrayRef<NT_Value> params) {
+  WireEncoder enc(0x0300);
+  for (auto& param : params) enc.WriteValue(param);
+  return ExecuteRpc(id, uid, enc.ToStringRef());
+}
+
+Message Message::ExecuteRpc(unsigned int id, unsigned int uid,
+                            llvm::StringRef params) {
+  Message msg(kExecuteRpc);
+  msg.m_str = StringValue(params);
+  msg.m_id = id;
+  msg.m_seq_num_uid = uid;
+  return msg;
+}
+
+Message Message::RpcResponse(unsigned int id, unsigned int uid,
+                             llvm::ArrayRef<NT_Value> results) {
+  WireEncoder enc(0x0300);
+  for (auto& result : results) enc.WriteValue(result);
+  return RpcResponse(id, uid, enc.ToStringRef());
+}
+
+Message Message::RpcResponse(unsigned int id, unsigned int uid,
+                             llvm::StringRef results) {
+  Message msg(kRpcResponse);
+  msg.m_str = StringValue(results);
+  msg.m_id = id;
+  msg.m_seq_num_uid = uid;
+  return msg;
+}
+
+void Message::Write(WireEncoder& encoder) const {
+  switch (m_type) {
+    case kKeepAlive:
+      encoder.Write8(kKeepAlive);
+      break;
+    case kClientHello:
+      encoder.Write8(kClientHello);
+      encoder.Write16(encoder.proto_rev());
+      if (encoder.proto_rev() < 0x0300u) return;
+      encoder.WriteString(m_str);
+      break;
+    case kProtoUnsup:
+      encoder.Write8(kProtoUnsup);
+      encoder.Write16(encoder.proto_rev());
+      break;
+    case kServerHelloDone:
+      encoder.Write8(kServerHelloDone);
+      break;
+    case kServerHello:
+      if (encoder.proto_rev() < 0x0300u) return;  // new message in version 3.0
+      encoder.Write8(kServerHello);
+      encoder.Write8(m_flags);
+      encoder.WriteString(m_str);
+      break;
+    case kClientHelloDone:
+      if (encoder.proto_rev() < 0x0300u) return;  // new message in version 3.0
+      encoder.Write8(kClientHelloDone);
+      break;
+    case kEntryAssign:
+      encoder.Write8(kEntryAssign);
+      encoder.WriteString(m_str);
+      encoder.WriteType(m_value->type());
+      encoder.Write16(m_id);
+      encoder.Write16(m_seq_num_uid);
+      if (encoder.proto_rev() >= 0x0300u) encoder.Write8(m_flags);
+      encoder.WriteValue(*m_value);
+      break;
+    case kEntryUpdate:
+      encoder.Write8(kEntryUpdate);
+      encoder.Write16(m_id);
+      encoder.Write16(m_seq_num_uid);
+      if (encoder.proto_rev() >= 0x0300u) encoder.Write8(m_value->type());
+      encoder.WriteValue(*m_value);
+      break;
+    case kFlagsUpdate:
+      if (encoder.proto_rev() < 0x0300u) return;  // new message in version 3.0
+      encoder.Write8(kFlagsUpdate);
+      encoder.Write16(m_id);
+      encoder.Write8(m_flags);
+      break;
+    case kEntryDelete:
+      if (encoder.proto_rev() < 0x0300u) return;  // new message in version 3.0
+      encoder.Write8(kEntryDelete);
+      encoder.Write16(m_id);
+      break;
+    case kClearEntries:
+      if (encoder.proto_rev() < 0x0300u) return;  // new message in version 3.0
+      encoder.Write8(kClearEntries);
+      encoder.Write32(kClearAllMagic);
+      break;
+    case kExecuteRpc:
+      if (encoder.proto_rev() < 0x0300u) return;  // new message in version 3.0
+      encoder.Write8(kExecuteRpc);
+      encoder.Write16(m_id);
+      encoder.Write16(m_seq_num_uid);
+      encoder.WriteString(m_str);
+      break;
+    case kRpcResponse:
+      if (encoder.proto_rev() < 0x0300u) return;  // new message in version 3.0
+      encoder.Write8(kRpcResponse);
+      encoder.Write16(m_id);
+      encoder.Write16(m_seq_num_uid);
+      encoder.WriteString(m_str);
+      break;
+    default:
+      break;
+  }
+}
diff --git a/src/Message.h b/src/Message.h
new file mode 100644
index 0000000000..ef70b6b377
--- /dev/null
+++ b/src/Message.h
@@ -0,0 +1,95 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2015. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#ifndef NT_MESSAGE_H_
+#define NT_MESSAGE_H_
+
+#include <memory>
+
+#include "Value.h"
+
+namespace ntimpl {
+
+class WireDecoder;
+class WireEncoder;
+
+class Message {
+ public:
+  enum MsgType {
+    kUnknown = -1,
+    kKeepAlive = 0x00,
+    kClientHello = 0x01,
+    kProtoUnsup = 0x02,
+    kServerHelloDone = 0x03,
+    kServerHello = 0x04,
+    kClientHelloDone = 0x05,
+    kEntryAssign = 0x10,
+    kEntryUpdate = 0x11,
+    kFlagsUpdate = 0x12,
+    kEntryDelete = 0x13,
+    kClearEntries = 0x14,
+    kExecuteRpc = 0x20,
+    kRpcResponse = 0x21
+  };
+
+  Message() : m_type(kUnknown), m_id(0), m_flags(0), m_seq_num_uid(0) {}
+
+  MsgType type() const { return m_type; }
+  bool Is(MsgType type) const { return type == m_type; }
+
+  // Read and write from wire representation
+  void Write(WireEncoder& encoder) const;
+  static bool Read(WireDecoder& decoder,
+                   NT_Type (*get_entry_type)(unsigned int id), Message* msg);
+
+  // Create messages without data
+  static Message KeepAlive() { return Message(kKeepAlive); }
+  static Message ProtoUnsup() { return Message(kProtoUnsup); }
+  static Message ServerHelloDone() { return Message(kServerHelloDone); }
+  static Message ClientHelloDone() { return Message(kClientHelloDone); }
+  static Message ClearEntries() { return Message(kClearEntries); }
+
+  // Create messages with data
+  static Message ClientHello(llvm::StringRef self_id);
+  static Message ServerHello(unsigned int flags, llvm::StringRef self_id);
+  static Message EntryAssign(llvm::StringRef name, unsigned int id,
+                             unsigned int seq_num, std::shared_ptr<Value> value,
+                             unsigned int flags);
+  static Message EntryUpdate(unsigned int id, unsigned int seq_num,
+                             std::shared_ptr<Value> value);
+  static Message FlagsUpdate(unsigned int id, unsigned int flags);
+  static Message EntryDelete(unsigned int id);
+  static Message ExecuteRpc(unsigned int id, unsigned int uid,
+                            llvm::ArrayRef<NT_Value> params);
+  static Message ExecuteRpc(unsigned int id, unsigned int uid,
+                            llvm::StringRef params);
+  static Message RpcResponse(unsigned int id, unsigned int uid,
+                             llvm::ArrayRef<NT_Value> results);
+  static Message RpcResponse(unsigned int id, unsigned int uid,
+                             llvm::StringRef results);
+
+  Message(const Message&) = delete;
+  Message& operator=(const Message&) = delete;
+  Message(Message&&) = default;
+  Message& operator=(Message&&) = default;
+
+ private:
+  Message(MsgType type);
+
+  MsgType m_type;
+
+  // Message data.  Use varies by message type.
+  StringValue m_str;
+  std::shared_ptr<Value> m_value;
+  unsigned int m_id;  // also used for proto_rev
+  unsigned int m_flags;
+  unsigned int m_seq_num_uid;
+};
+
+}  // namespace ntimpl
+
+#endif  // NT_MESSAGE_H_
diff --git a/src/MessageReader.cpp b/src/MessageReader.cpp
deleted file mode 100644
index 9fc308b1af..0000000000
--- a/src/MessageReader.cpp
+++ /dev/null
@@ -1,170 +0,0 @@
-/*----------------------------------------------------------------------------*/
-/* Copyright (c) FIRST 2015. All Rights Reserved.                             */
-/* Open Source Software - may be modified and shared by FRC teams. The code   */
-/* must be accompanied by the FIRST BSD license file in the root directory of */
-/* the project.                                                               */
-/*----------------------------------------------------------------------------*/
-
-#include "MessageReader.h"
-
-#include <cassert>
-#include <cstdlib>
-#include <cstring>
-
-#include "internal.h"
-#include "leb128.h"
-
-using namespace ntimpl;
-
-void MessageHandler::anchor() {}
-
-MessageReader::MessageReader(MessageHandler& handler, raw_istream& is,
-                             unsigned int proto_rev)
-    : WireDecoder(is, proto_rev), m_handler(handler) {}
-
-MessageReader::~MessageReader() {}
-
-bool MessageReader::ReadMessage() {
-  unsigned int msg_type;
-  if (!Read8(&msg_type)) return false;
-  switch (msg_type) {
-    case NT_MSG_KEEP_ALIVE:
-      m_handler.GotKeepAlive();
-      break;
-    case NT_MSG_CLIENT_HELLO: {
-      unsigned int proto_rev;
-      if (!Read16(&proto_rev)) return false;
-      StringValue self_id;
-      // This intentionally uses the provided proto_rev instead of
-      // m_proto_rev.
-      if (proto_rev >= 0x0300u) {
-        if (!ReadString(&self_id)) return false;
-      }
-      m_handler.GotClientHello(proto_rev, std::move(self_id));
-      break;
-    }
-    case NT_MSG_PROTO_UNSUP: {
-      unsigned int proto_rev;
-      if (!Read16(&proto_rev)) return false;
-      m_handler.GotProtoUnsup(proto_rev);
-      break;
-    }
-    case NT_MSG_SERVER_HELLO_DONE:
-      if (m_proto_rev < 0x0300u) {
-        m_error = "received SERVER_HELLO_DONE in protocol < 3.0";
-        return false;
-      }
-      m_handler.GotServerHelloDone();
-      break;
-    case NT_MSG_CLIENT_HELLO_DONE:
-      if (m_proto_rev < 0x0300u) {
-        m_error = "received CLIENT_HELLO_DONE in protocol < 3.0";
-        return false;
-      }
-      m_handler.GotClientHelloDone();
-      break;
-    case NT_MSG_ENTRY_ASSIGN: {
-      StringValue name;
-      if (!ReadString(&name)) return false;
-      NT_Type type;
-      if (!ReadType(&type)) return false;
-      unsigned int id, seq_num;
-      if (!Read16(&id)) return false;
-      if (!Read16(&seq_num)) return false;
-      unsigned int flags = 0;
-      if (m_proto_rev >= 0x0300u) {
-        if (!Read8(&flags)) return false;
-      }
-      Value value;
-      if (!ReadValue(type, &value)) return false;
-      m_handler.GotEntryAssign(std::move(name), id, seq_num, std::move(value),
-                               flags);
-      break;
-    }
-    case NT_MSG_ENTRY_UPDATE: {
-      unsigned int id, seq_num;
-      Value value;
-      if (!Read16(&id)) return false;
-      if (!Read16(&seq_num)) return false;
-      NT_Type type;
-      if (m_proto_rev >= 0x0300u) {
-        unsigned int itype;
-        if (!Read8(&itype)) return false;
-        type = static_cast<NT_Type>(itype);
-      } else
-        type = m_handler.GetEntryType(id);
-      if (!ReadValue(type, &value)) return false;
-      m_handler.GotEntryUpdate(id, seq_num, std::move(value));
-      break;
-    }
-    case NT_MSG_FLAGS_UPDATE: {
-      if (m_proto_rev < 0x0300u) {
-        m_error = "received FLAGS_UPDATE in protocol < 3.0";
-        return false;
-      }
-      unsigned int id, flags;
-      if (!Read16(&id)) return false;
-      if (!Read8(&flags)) return false;
-      m_handler.GotFlagsUpdate(id, flags);
-      break;
-    }
-    case NT_MSG_ENTRY_DELETE: {
-      if (m_proto_rev < 0x0300u) {
-        m_error = "received ENTRY_DELETE in protocol < 3.0";
-        return false;
-      }
-      unsigned int id;
-      if (!Read16(&id)) return false;
-      m_handler.GotEntryDelete(id);
-      break;
-    }
-    case NT_MSG_CLEAR_ENTRIES: {
-      if (m_proto_rev < 0x0300u) {
-        m_error = "received CLEAR_ENTRIES in protocol < 3.0";
-        return false;
-      }
-      unsigned long magic;
-      if (!Read32(&magic)) return false;
-      if (magic != NT_CLEAR_ALL_MAGIC) {
-        m_error = "received incorrect CLEAR_ENTRIES magic value, ignoring";
-        return true;
-      }
-      m_handler.GotClearEntries();
-      break;
-    }
-    case NT_MSG_EXECUTE_RPC: {
-      if (m_proto_rev < 0x0300u) {
-        m_error = "received EXECUTE_RPC in protocol < 3.0";
-        return false;
-      }
-      unsigned int id, uid;
-      if (!Read16(&id)) return false;
-      if (!Read16(&uid)) return false;
-      unsigned long size;
-      if (!ReadUleb128(&size)) return false;
-      const char* params;
-      if (!Read(&params, size)) return false;
-      m_handler.GotExecuteRpc(id, uid, llvm::StringRef(params, size));
-      break;
-    }
-    case NT_MSG_RPC_RESPONSE: {
-      if (m_proto_rev < 0x0300u) {
-        m_error = "received RPC_RESPONSE in protocol < 3.0";
-        return false;
-      }
-      unsigned int id, uid;
-      if (!Read16(&id)) return false;
-      if (!Read16(&uid)) return false;
-      unsigned long size;
-      if (!ReadUleb128(&size)) return false;
-      const char* results;
-      if (!Read(&results, size)) return false;
-      m_handler.GotRpcResponse(id, uid, llvm::StringRef(results, size));
-      break;
-    }
-    default:
-      m_error = "unrecognized message type";
-      return false;
-  }
-  return true;
-}
diff --git a/src/MessageReader.h b/src/MessageReader.h
deleted file mode 100644
index f0ff76e259..0000000000
--- a/src/MessageReader.h
+++ /dev/null
@@ -1,71 +0,0 @@
-/*----------------------------------------------------------------------------*/
-/* Copyright (c) FIRST 2015. All Rights Reserved.                             */
-/* Open Source Software - may be modified and shared by FRC teams. The code   */
-/* must be accompanied by the FIRST BSD license file in the root directory of */
-/* the project.                                                               */
-/*----------------------------------------------------------------------------*/
-
-#ifndef NT_MESSAGEREADER_H_
-#define NT_MESSAGEREADER_H_
-
-#include "Value.h"
-#include "WireDecoder.h"
-
-namespace ntimpl {
-
-class MessageHandler {
-  void anchor();
-
- public:
-  // Needed for protocol rev 2.0 ENTRY_UPDATE messages.
-  virtual NT_Type GetEntryType(unsigned int id) = 0;
-
-  virtual ~MessageHandler() {}
-  virtual void GotKeepAlive() = 0;
-  virtual void GotClientHello(unsigned int proto_rev,
-                              StringValue&& self_id) = 0;
-  virtual void GotProtoUnsup(unsigned int proto_rev) = 0;
-  virtual void GotServerHelloDone() = 0;
-  virtual void GotServerHello(unsigned int flags, StringValue&& self_id) = 0;
-  virtual void GotClientHelloDone() = 0;
-  virtual void GotEntryAssign(StringValue&& name, unsigned int id,
-                              unsigned int seq_num, Value&& value,
-                              unsigned int flags) = 0;
-  virtual void GotEntryUpdate(unsigned int id, unsigned int seq_num,
-                              Value&& value) = 0;
-  virtual void GotFlagsUpdate(unsigned int id, unsigned int flags) = 0;
-  virtual void GotEntryDelete(unsigned int id) = 0;
-  virtual void GotClearEntries() = 0;
-  virtual void GotExecuteRpc(unsigned int id, unsigned int uid,
-                             llvm::StringRef params) = 0;
-  virtual void GotRpcResponse(unsigned int id, unsigned int uid,
-                              llvm::StringRef results) = 0;
-
-  MessageHandler() = default;
-  MessageHandler(const MessageHandler&) = delete;
-  MessageHandler& operator=(const MessageHandler&) = delete;
-};
-
-class MessageReader : private WireDecoder {
- public:
-  explicit MessageReader(MessageHandler& handler, raw_istream& is,
-                         unsigned int proto_rev);
-  ~MessageReader();
-
-  bool ReadMessage();
-
-  using WireDecoder::set_proto_rev;
-  using WireDecoder::proto_rev;
-  using WireDecoder::Reset;
-  using WireDecoder::error;
-
-  MessageReader(const MessageReader&) = delete;
-  MessageReader& operator=(const MessageReader&) = delete;
-
- private:
-  MessageHandler& m_handler;
-};
-
-}  // namespace ntimpl
-
-#endif  // NT_MESSAGEREADER_H_
diff --git a/src/MessageWriter.cpp b/src/MessageWriter.cpp
deleted file mode 100644
index c481dabbaf..0000000000
--- a/src/MessageWriter.cpp
+++ /dev/null
@@ -1,110 +0,0 @@
-/*----------------------------------------------------------------------------*/
-/* Copyright (c) FIRST 2015. All Rights Reserved.                             */
-/* Open Source Software - may be modified and shared by FRC teams. The code   */
-/* must be accompanied by the FIRST BSD license file in the root directory of */
-/* the project.                                                               */
-/*----------------------------------------------------------------------------*/
-
-#include "MessageWriter.h"
-
-#include "internal.h"
-
-using namespace ntimpl;
-
-MessageWriter::~MessageWriter() {}
-
-void MessageWriter::WriteKeepAlive() { Write8(NT_MSG_KEEP_ALIVE); }
-
-void MessageWriter::WriteClientHello(llvm::StringRef self_id) {
-  Write8(NT_MSG_CLIENT_HELLO);
-  Write16(m_proto_rev);
-  if (m_proto_rev < 0x0300u) return;
-  WriteString(self_id);
-}
-
-void MessageWriter::WriteProtoUnsup() {
-  Write8(NT_MSG_PROTO_UNSUP);
-  Write16(m_proto_rev);
-}
-
-void MessageWriter::WriteServerHelloDone() { Write8(NT_MSG_SERVER_HELLO_DONE); }
-
-void MessageWriter::WriteServerHello(unsigned int flags,
-                                     llvm::StringRef self_id) {
-  if (m_proto_rev < 0x0300u) return;  // new message in version 3.0
-  Write8(NT_MSG_SERVER_HELLO);
-  Write8(flags);
-  WriteString(self_id);
-}
-
-void MessageWriter::WriteClientHelloDone() {
-  if (m_proto_rev < 0x0300u) return;  // new message in version 3.0
-  Write8(NT_MSG_CLIENT_HELLO_DONE);
-}
-
-void MessageWriter::WriteEntryAssign(llvm::StringRef name, unsigned int id,
-                                     unsigned int seq_num,
-                                     const NT_Value& value,
-                                     unsigned int flags) {
-  Write8(NT_MSG_ENTRY_ASSIGN);
-  WriteString(name);
-  WriteType(value.type);
-  Write16(id);
-  Write16(seq_num);
-  if (m_proto_rev >= 0x0300u) Write8(flags);
-  WriteValue(value);
-}
-
-void MessageWriter::WriteEntryUpdate(unsigned int id, unsigned int seq_num,
-                                     const NT_Value& value) {
-  Write8(NT_MSG_ENTRY_UPDATE);
-  Write16(id);
-  Write16(seq_num);
-  if (m_proto_rev >= 0x0300u) Write8(value.type);
-  WriteValue(value);
-}
-
-void MessageWriter::WriteFlagsUpdate(unsigned int id, unsigned int flags) {
-  if (m_proto_rev < 0x0300u) return;  // new message in version 3.0
-  Write8(NT_MSG_FLAGS_UPDATE);
-  Write16(id);
-  Write8(flags);
-}
-
-void MessageWriter::WriteEntryDelete(unsigned int id) {
-  if (m_proto_rev < 0x0300u) return;  // new message in version 3.0
-  Write8(NT_MSG_ENTRY_DELETE);
-  Write16(id);
-}
-
-void MessageWriter::WriteClearEntries() {
-  if (m_proto_rev < 0x0300u) return;  // new message in version 3.0
-  Write8(NT_MSG_CLEAR_ENTRIES);
-  Write32(NT_CLEAR_ALL_MAGIC);
-}
-
-void MessageWriter::WriteExecuteRpc(unsigned int id, unsigned int uid,
-                                    llvm::ArrayRef<NT_Value> params) {
-  WriteRpc(NT_MSG_EXECUTE_RPC, id, uid, params);
-}
-
-void MessageWriter::WriteRpcResponse(unsigned int id, unsigned int uid,
-                                     llvm::ArrayRef<NT_Value> results) {
-  WriteRpc(NT_MSG_RPC_RESPONSE, id, uid, results);
-}
-
-void MessageWriter::WriteRpc(unsigned int msg_type, unsigned int id,
-                             unsigned int uid,
-                             llvm::ArrayRef<NT_Value> values) {
-  if (m_proto_rev < 0x0300u) return;  // new message in version 3.0
-
-  Write8(msg_type);
-  Write16(id);
-  Write16(uid);
-
-  unsigned long len = 0;
-  for (auto& value : values) len += GetValueSize(value);
-  WriteUleb128(len);
-
-  for (auto& value : values) WriteValue(value);
-}
diff --git a/src/MessageWriter.h b/src/MessageWriter.h
deleted file mode 100644
index d21a96e197..0000000000
--- a/src/MessageWriter.h
+++ /dev/null
@@ -1,59 +0,0 @@
-/*----------------------------------------------------------------------------*/
-/* Copyright (c) FIRST 2015. All Rights Reserved.                             */
-/* Open Source Software - may be modified and shared by FRC teams. The code   */
-/* must be accompanied by the FIRST BSD license file in the root directory of */
-/* the project.                                                               */
-/*----------------------------------------------------------------------------*/
-
-#ifndef NT_MESSAGEWRITER_H_
-#define NT_MESSAGEWRITER_H_
-
-#include "WireEncoder.h"
-
-#include "llvm/ArrayRef.h"
-#include "llvm/StringRef.h"
-
-namespace ntimpl {
-
-class MessageWriter : private WireEncoder {
- public:
-  explicit MessageWriter(unsigned int proto_rev) : WireEncoder(proto_rev) {}
-  ~MessageWriter();
-
-  using WireEncoder::set_proto_rev;
-  using WireEncoder::proto_rev;
-  using WireEncoder::Reset;
-  using WireEncoder::error;
-  using WireEncoder::data;
-  using WireEncoder::size;
-
-  void WriteKeepAlive();
-  void WriteClientHello(llvm::StringRef self_id);
-  void WriteProtoUnsup();
-  void WriteServerHelloDone();
-  void WriteServerHello(unsigned int flags, llvm::StringRef self_id);
-  void WriteClientHelloDone();
-  void WriteEntryAssign(llvm::StringRef name, unsigned int id,
-                        unsigned int seq_num, const NT_Value& value,
-                        unsigned int flags);
-  void WriteEntryUpdate(unsigned int id, unsigned int seq_num,
-                        const NT_Value& value);
-  void WriteFlagsUpdate(unsigned int id, unsigned int flags);
-  void WriteEntryDelete(unsigned int id);
-  void WriteClearEntries();
-  void WriteExecuteRpc(unsigned int id, unsigned int uid,
-                       llvm::ArrayRef<NT_Value> params);
-  void WriteRpcResponse(unsigned int id, unsigned int uid,
-                        llvm::ArrayRef<NT_Value> results);
-
-  MessageWriter(const MessageWriter&) = delete;
-  MessageWriter& operator=(const MessageWriter&) = delete;
-
- private:
-  void WriteRpc(unsigned int msg_type, unsigned int id, unsigned int uid,
-                llvm::ArrayRef<NT_Value> values);
-};
-
-}  // namespace ntimpl
-
-#endif  // NT_MESSAGEWRITER_H_
diff --git a/src/Value.h b/src/Value.h
index 1015e36ba5..d028110e32 100644
--- a/src/Value.h
+++ b/src/Value.h
@@ -18,6 +18,7 @@
 
 namespace ntimpl {
 
+class Message;
 class StringValueTest;
 class Storage;
 class Value;
@@ -28,6 +29,7 @@ class WireDecoder;
  * C++ wrapper class around NT_String.
  */
 class StringValue : private NT_String {
+  friend class Message;
   friend class StringValueTest;
   friend class Value;
   friend class WireDecoder;
@@ -83,8 +85,9 @@ inline bool operator!=(const StringValue& lhs, llvm::StringRef rhs) {
  * C++ wrapper class around NT_Value.
  */
 class Value : private NT_Value {
-  friend class ValueTest;
+  friend class Message;
   friend class Storage;
+  friend class ValueTest;
   friend class WireDecoder;
  public:
   Value() { NT_InitValue(this); }
diff --git a/src/WireDecoder.cpp b/src/WireDecoder.cpp
index 8682c997a9..d161e832e2 100644
--- a/src/WireDecoder.cpp
+++ b/src/WireDecoder.cpp
@@ -12,7 +12,6 @@
 #include <cstdlib>
 #include <cstring>
 
-#include "internal.h"
 #include "leb128.h"
 
 using namespace ntimpl;
diff --git a/src/WireDecoder.h b/src/WireDecoder.h
index 053ea90728..749279a9dd 100644
--- a/src/WireDecoder.h
+++ b/src/WireDecoder.h
@@ -42,6 +42,8 @@ class WireDecoder {
    */
   const char* error() const { return m_error; }
 
+  void set_error(const char* error) { m_error = error; }
+
   /* Reads the specified number of bytes.
    * @param buf pointer to read data (output parameter)
    * @param len number of bytes to read
diff --git a/src/WireEncoder.cpp b/src/WireEncoder.cpp
index 47fc7c13a5..9c5a3c66df 100644
--- a/src/WireEncoder.cpp
+++ b/src/WireEncoder.cpp
@@ -12,7 +12,6 @@
 #include <cstdlib>
 #include <cstring>
 
-#include "internal.h"
 #include "leb128.h"
 
 using namespace ntimpl;
diff --git a/src/WireEncoder.h b/src/WireEncoder.h
index 487c0f4710..2f6a804217 100644
--- a/src/WireEncoder.h
+++ b/src/WireEncoder.h
@@ -50,6 +50,10 @@ class WireEncoder {
   /* Returns number of bytes written to memory buffer. */
   std::size_t size() const { return m_cur - m_start; }
 
+  llvm::StringRef ToStringRef() const {
+    return llvm::StringRef(m_start, m_cur - m_start);
+  }
+
   /* Ensures the buffer has sufficient space to write len bytes.  Reallocates
    * the buffer if necessary.
    */
diff --git a/src/internal.h b/src/internal.h
deleted file mode 100644
index 1d9f0849ff..0000000000
--- a/src/internal.h
+++ /dev/null
@@ -1,33 +0,0 @@
-/*----------------------------------------------------------------------------*/
-/* Copyright (c) FIRST 2015. All Rights Reserved.                             */
-/* Open Source Software - may be modified and shared by FRC teams. The code   */
-/* must be accompanied by the FIRST BSD license file in the root directory of */
-/* the project.                                                               */
-/*----------------------------------------------------------------------------*/
-
-#ifndef NT_INTERNAL_H_
-#define NT_INTERNAL_H_
-
-namespace ntimpl {
-
-enum MsgType {
-  NT_MSG_KEEP_ALIVE = 0x00,
-  NT_MSG_CLIENT_HELLO = 0x01,
-  NT_MSG_PROTO_UNSUP = 0x02,
-  NT_MSG_SERVER_HELLO_DONE = 0x03,
-  NT_MSG_SERVER_HELLO = 0x04,
-  NT_MSG_CLIENT_HELLO_DONE = 0x05,
-  NT_MSG_ENTRY_ASSIGN = 0x10,
-  NT_MSG_ENTRY_UPDATE = 0x11,
-  NT_MSG_FLAGS_UPDATE = 0x12,
-  NT_MSG_ENTRY_DELETE = 0x13,
-  NT_MSG_CLEAR_ENTRIES = 0x14,
-  NT_MSG_EXECUTE_RPC = 0x20,
-  NT_MSG_RPC_RESPONSE = 0x21
-};
-
-#define NT_CLEAR_ALL_MAGIC 0xD06CB27Aul
-
-}  // namespace ntimpl
-
-#endif  // NT_INTERNAL_H_