diff --git a/renderdoc/driver/shaders/spirv/CMakeLists.txt b/renderdoc/driver/shaders/spirv/CMakeLists.txt
index d0615469a..d0d96f458 100644
--- a/renderdoc/driver/shaders/spirv/CMakeLists.txt
+++ b/renderdoc/driver/shaders/spirv/CMakeLists.txt
@@ -91,6 +91,8 @@ endif()
 set(sources
     spirv_common.cpp
     spirv_common.h
+    spirv_editor.h
+    spirv_editor.cpp
     spirv_compile.cpp
     spirv_disassemble.cpp
     spirv_stringise.cpp
diff --git a/renderdoc/driver/shaders/spirv/renderdoc_spirv.vcxproj b/renderdoc/driver/shaders/spirv/renderdoc_spirv.vcxproj
index ea5cbffc6..3e30cabad 100644
--- a/renderdoc/driver/shaders/spirv/renderdoc_spirv.vcxproj
+++ b/renderdoc/driver/shaders/spirv/renderdoc_spirv.vcxproj
@@ -163,6 +163,7 @@
       <PrecompiledHeaderFile>precompiled.h</PrecompiledHeaderFile>
       <ForcedIncludeFiles>precompiled.h</ForcedIncludeFiles>
     </ClCompile>
+    <ClCompile Include="spirv_editor.cpp" />
     <ClCompile Include="spirv_stringise.cpp" />
   </ItemGroup>
   <ItemGroup>
@@ -218,6 +219,7 @@
     <ClInclude Include="..\..\..\3rdparty\glslang\SPIRV\spvIR.h" />
     <ClInclude Include="precompiled.h" />
     <ClInclude Include="spirv_common.h" />
+    <ClInclude Include="spirv_editor.h" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
diff --git a/renderdoc/driver/shaders/spirv/renderdoc_spirv.vcxproj.filters b/renderdoc/driver/shaders/spirv/renderdoc_spirv.vcxproj.filters
index 5a31c1c5c..448bb5405 100644
--- a/renderdoc/driver/shaders/spirv/renderdoc_spirv.vcxproj.filters
+++ b/renderdoc/driver/shaders/spirv/renderdoc_spirv.vcxproj.filters
@@ -145,6 +145,7 @@
       <Filter>PCH</Filter>
     </ClCompile>
     <ClCompile Include="spirv_stringise.cpp" />
+    <ClCompile Include="spirv_editor.cpp" />
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\..\..\3rdparty\glslang\OGLCompilersDLL\InitializeDll.h">
@@ -301,5 +302,6 @@
     <ClInclude Include="precompiled.h">
       <Filter>PCH</Filter>
     </ClInclude>
+    <ClInclude Include="spirv_editor.h" />
   </ItemGroup>
 </Project>
\ No newline at end of file
diff --git a/renderdoc/driver/shaders/spirv/spirv_editor.cpp b/renderdoc/driver/shaders/spirv/spirv_editor.cpp
new file mode 100644
index 000000000..a9e1105e1
--- /dev/null
+++ b/renderdoc/driver/shaders/spirv/spirv_editor.cpp
@@ -0,0 +1,72 @@
+/******************************************************************************
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Baldur Karlsson
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ ******************************************************************************/
+
+#include "spirv_editor.h"
+#include "common/common.h"
+
+SPIRVEditor::SPIRVEditor(std::vector<uint32_t> &spirvWords) : spirv(spirvWords)
+{
+  if(spirvWords.size() < 5 || spirvWords[0] != spv::MagicNumber)
+  {
+    RDCERR("Empty or invalid SPIR-V module");
+    return;
+  }
+
+  moduleVersion.major = uint8_t((spirvWords[1] & 0x00ff0000) >> 16);
+  moduleVersion.minor = uint8_t((spirvWords[1] & 0x0000ff00) >> 8);
+  generator = spirvWords[2];
+  idBound = SPIRVIterator(spirvWords, 3);
+
+  // [4] is reserved
+  RDCASSERT(spirv[4] == 0);
+
+  SPIRVIterator it(spirvWords, 5);
+
+  while(it)
+  {
+    spv::Op opcode = it.opcode();
+
+    if(opcode == spv::OpEntryPoint)
+    {
+      SPIRVEntry entry;
+      entry.iter = it;
+      entry.id = it.word(2);
+      entry.name = (const char *)&it.word(3);
+
+      entries.push_back(entry);
+    }
+
+    it++;
+  }
+}
+
+uint32_t SPIRVEditor::MakeId()
+{
+  if(!idBound)
+    return 0;
+
+  uint32_t ret = *idBound;
+  (*idBound)++;
+  return ret;
+}
diff --git a/renderdoc/driver/shaders/spirv/spirv_editor.h b/renderdoc/driver/shaders/spirv/spirv_editor.h
new file mode 100644
index 000000000..dafb8732f
--- /dev/null
+++ b/renderdoc/driver/shaders/spirv/spirv_editor.h
@@ -0,0 +1,159 @@
+/******************************************************************************
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2018 Baldur Karlsson
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ ******************************************************************************/
+
+#pragma once
+
+#include <stdint.h>
+#include <string>
+#include <vector>
+#include "3rdparty/glslang/SPIRV/spirv.hpp"
+
+class SPIRVOperation;
+
+class SPIRVIterator
+{
+public:
+  // constructors
+  SPIRVIterator() = default;
+  SPIRVIterator(std::vector<uint32_t> &w, size_t o) : words(&w), offset(o) {}
+  // increment to the next op
+  SPIRVIterator &operator++(int) { return operator++(); }
+  SPIRVIterator &operator++()
+  {
+    offset += cur() >> spv::WordCountShift;
+    return *this;
+  }
+  // utility functions
+  std::vector<uint32_t>::iterator it() { return words->begin() + offset; }
+  operator bool() const { return words != NULL && offset < words->size(); }
+  uint32_t &operator*() { return cur(); }
+  const uint32_t &operator*() const { return cur(); }
+  spv::Op opcode() { return spv::Op(cur() & spv::OpCodeMask); }
+  uint32_t &word(size_t idx) { return words->at(offset + idx); }
+  const uint32_t &word(size_t idx) const { return words->at(offset + idx); }
+  size_t size() const { return cur() >> spv::WordCountShift; }
+private:
+  inline uint32_t &cur() { return words->at(offset); }
+  inline const uint32_t &cur() const { return words->at(offset); }
+  // we make this a friend so it can poke directly into words when it wants to edit
+  friend class SPIRVOperation;
+
+  std::vector<uint32_t> *words = NULL;
+  size_t offset = 0;
+};
+
+class SPIRVOperation
+{
+public:
+  // constructor of a synthetic operation, from an operation & subsequent words, calculates the
+  // length then constructs the first word with opcode + length.
+  template <typename WordContainer>
+  SPIRVOperation(spv::Op op, const WordContainer &data)
+  {
+    auto a = std::begin(data);
+    auto b = std::end(data);
+    size_t count = 1 + (b - a);
+    words.resize(data.size());
+    words[0] = MakeHeader(op, data.size());
+    words.insert(words.begin() + 1, a, b);
+
+    iter = SPIRVIterator(words, 0);
+  }
+
+  // constructor that takes existing words from elsewhere and just references it.
+  // Since this is iterator based, normal iteration invalidation rules apply, if you modify earlier
+  // in the SPIR-V this operation will become invalid.
+  SPIRVOperation(SPIRVIterator it) : iter(it) {}
+  uint32_t &operator[](size_t idx) { return iter.word(idx); }
+  const uint32_t &operator[](size_t idx) const { return iter.word(idx); }
+  size_t size() const { return iter.size(); }
+  void push_back(uint32_t word)
+  {
+    spv::Op op = iter.opcode();
+    size_t count = iter.size();
+    iter.words->insert(iter.it() + count, word);
+
+    // since the length is in the high-order bits, we have to extract/increment/insert instead of
+    // just incrementing. Boo!
+    *iter = MakeHeader(op, count + 1);
+  }
+
+private:
+  inline uint32_t MakeHeader(spv::Op op, size_t WordCount)
+  {
+    return (uint32_t(op) & spv::OpCodeMask) | (uint16_t(WordCount) << spv::WordCountShift);
+  }
+
+  // everything is based around this iterator, which may point into our local storage or to external
+  // storage.
+  SPIRVIterator iter;
+
+  // may not be used, if we refer to an external iterator
+  std::vector<uint32_t> words;
+};
+
+struct SPIRVEntry
+{
+  uint32_t id;
+  std::string name;
+  SPIRVIterator iter;
+};
+
+class SPIRVEditor
+{
+public:
+  SPIRVEditor(std::vector<uint32_t> &spirvWords);
+
+  std::vector<uint32_t> &GetWords() { return spirv; }
+  uint32_t MakeId();
+  void AddDecoration(const SPIRVOperation &op);
+  void AddType(const SPIRVOperation &op);
+  void AddVariable(const SPIRVOperation &op);
+  void AddFunction(const SPIRVOperation *ops, size_t count);
+
+  // simple properties that are public.
+  struct
+  {
+    uint8_t major = 1, minor = 0;
+  } moduleVersion;
+  uint32_t generator = 0;
+
+  spv::SourceLanguage sourceLang = spv::SourceLanguageUnknown;
+  uint32_t sourceVer = 0;
+
+  const std::vector<SPIRVEntry> &GetEntries() { return entries; }
+private:
+  SPIRVIterator idBound;
+
+  struct
+  {
+    SPIRVIterator decoration;
+    SPIRVIterator typeVar;
+    SPIRVIterator function;
+  } globaliters;
+
+  std::vector<SPIRVEntry> entries;
+
+  std::vector<uint32_t> &spirv;
+};