diff --git a/generator/CMakeLists.txt b/generator/CMakeLists.txt
index 4e169859e8..d3521b1aa0 100644
--- a/generator/CMakeLists.txt
+++ b/generator/CMakeLists.txt
@@ -27,7 +27,7 @@ endif()
 
 function(Generate)
     set(oneValueArgs LIB_NAME LIB_TYPE PRINT_NAME EXECUTABLE)
-    set(multiValueArgs COMMAND_LINE_ARGS EXTRA_DEPS SOURCE)
+    set(multiValueArgs COMMAND_LINE_ARGS EXTRA_DEPS EXTRA_SOURCES)
     cmake_parse_arguments(G "" "${oneValueArgs}" "${multiValueArgs}" ${ARGN})
 
     execute_process(
@@ -57,7 +57,7 @@ function(Generate)
     )
 
     add_library(${G_LIB_NAME} ${G_LIB_TYPE}
-        ${G_SOURCE}
+        ${G_EXTRA_SOURCES}
         ${OUTPUTS}
     )
 endfunction()
diff --git a/src/wire/CMakeLists.txt b/src/wire/CMakeLists.txt
index f4f64bd08a..1a68638167 100644
--- a/src/wire/CMakeLists.txt
+++ b/src/wire/CMakeLists.txt
@@ -23,6 +23,9 @@ Generate(
     COMMAND_LINE_ARGS
         ${GENERATOR_COMMON_ARGS}
         -T wire
+    EXTRA_SOURCES
+        ${WIRE_DIR}/WireCmd.cpp
+        ${WIRE_DIR}/WireCmd.h
 )
 target_include_directories(wire_autogen PRIVATE ${CMAKE_CURRENT_SOURCE_DIR})
 target_include_directories(wire_autogen PUBLIC ${GENERATED_DIR})
@@ -31,9 +34,9 @@ SetCXX14(wire_autogen)
 SetPic(wire_autogen)
 
 add_library(nxt_wire STATIC
+    ${WIRE_DIR}/TerribleCommandBuffer.cpp
     ${WIRE_DIR}/TerribleCommandBuffer.h
-    ${WIRE_DIR}/WireCmd.cpp
-    ${WIRE_DIR}/WireCmd.h
+    ${WIRE_DIR}/Wire.h
 )
 target_link_libraries(nxt_wire wire_autogen)
 SetCXX14(nxt_wire)
diff --git a/src/wire/TerribleCommandBuffer.cpp b/src/wire/TerribleCommandBuffer.cpp
new file mode 100644
index 0000000000..f54f5c6dbd
--- /dev/null
+++ b/src/wire/TerribleCommandBuffer.cpp
@@ -0,0 +1,52 @@
+// Copyright 2017 The NXT Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "TerribleCommandBuffer.h"
+
+namespace nxt {
+namespace wire {
+
+    TerribleCommandBuffer::TerribleCommandBuffer() {
+    }
+
+    TerribleCommandBuffer::TerribleCommandBuffer(CommandHandler* handler) : handler(handler) {
+    }
+
+    void TerribleCommandBuffer::SetHandler(CommandHandler* handler) {
+        this->handler = handler;
+    }
+
+    void* TerribleCommandBuffer::GetCmdSpace(size_t size) {
+        if (size > sizeof(buffer)) {
+            return nullptr;
+        }
+
+        uint8_t* result = &buffer[offset];
+        offset += size;
+
+        if (offset > sizeof(buffer)) {
+            Flush();
+            return GetCmdSpace(size);
+        }
+
+        return result;
+    }
+
+    void TerribleCommandBuffer::Flush() {
+        handler->HandleCommands(buffer, offset);
+        offset = 0;
+    }
+
+}
+}
diff --git a/src/wire/TerribleCommandBuffer.h b/src/wire/TerribleCommandBuffer.h
index c81263ce65..4c0ab5fe66 100644
--- a/src/wire/TerribleCommandBuffer.h
+++ b/src/wire/TerribleCommandBuffer.h
@@ -24,36 +24,13 @@ namespace wire {
 
 class TerribleCommandBuffer : public CommandSerializer {
     public:
-        TerribleCommandBuffer() {
-        }
+        TerribleCommandBuffer();
+        TerribleCommandBuffer(CommandHandler* handler);
 
-        TerribleCommandBuffer(CommandHandler* handler) : handler(handler) {
-        }
+        void SetHandler(CommandHandler* handler);
 
-        void SetHandler(CommandHandler* handler) {
-            this->handler = handler;
-        }
-
-        void* GetCmdSpace(size_t size) {
-            if (size > sizeof(buffer)) {
-                return nullptr;
-            }
-
-            uint8_t* result = &buffer[offset];
-            offset += size;
-
-            if (offset > sizeof(buffer)) {
-                Flush();
-                return GetCmdSpace(size);
-            }
-
-            return result;
-        }
-
-        void Flush() {
-            handler->HandleCommands(buffer, offset);
-            offset = 0;
-        }
+        void* GetCmdSpace(size_t size) override;
+        void Flush() override;
 
     private:
         CommandHandler* handler = nullptr;