diff --git a/kraken/KRShaderManager.cpp b/kraken/KRShaderManager.cpp
index 2fb29dd..a916d1f 100644
--- a/kraken/KRShaderManager.cpp
+++ b/kraken/KRShaderManager.cpp
@@ -38,6 +38,7 @@
 
 KRShaderManager::KRShaderManager(KRContext& context) : KRResourceManager(context)
 , m_initializedGlslang(false)
+, m_includer(&context)
 {
 
 }
@@ -288,7 +289,7 @@ bool KRShaderManager::compileAll(KRBundle* outputBundle, KRUnknown* logResource)
       shader.setStringsWithLengthsAndNames(sourceText, sourceLen, sourceNameStr, 1);
       //shader.setStrings(&sourceStr, 1);
 
-      if (shader.parse(&resources, defaultVersion, false, messages)) {
+      if (shader.parse(&resources, defaultVersion, false, messages, m_includer)) {
         program.addShader(&shader);
       } else {
         const char* log = shader.getInfoLog();
@@ -358,3 +359,38 @@ bool KRShaderManager::compileAll(KRBundle* outputBundle, KRUnknown* logResource)
 
   return success;
 }
+
+KRShaderManager::Includer::Includer(KRContext* context)
+  : m_context(context)
+{}
+
+glslang::TShader::Includer::IncludeResult* KRShaderManager::Includer::includeSystem(
+  const char* headerName,
+  const char* includerName,
+  size_t inclusionDepth)
+{
+  fprintf(stderr, "includeSystem(%s, %s, %llu)\n", headerName, includerName, inclusionDepth);
+  return nullptr;
+}
+glslang::TShader::Includer::IncludeResult* KRShaderManager::Includer::includeLocal(
+  const char* headerName,
+  const char* includerName,
+  size_t inclusionDepth)
+{
+  std::string name = KRResource::GetFileBase(headerName);
+  std::string extension = KRResource::GetFileExtension(headerName);
+  KRSource* source = m_context->getSourceManager()->get(name, extension);
+  if (!source) {
+    return nullptr;
+  }
+  KRDataBlock* data = source->getData();
+  data->lock();
+  const char* sourceString = static_cast<const char*>(data->getStart());
+  return new IncludeResult(std::string(headerName), sourceString, data->getSize(), static_cast<void*>(data));
+}
+
+void KRShaderManager::Includer::releaseInclude(IncludeResult* includeResult)
+{
+  KRDataBlock* data = static_cast<KRDataBlock*>(includeResult->userData);
+  data->unlock();
+}
diff --git a/kraken/KRShaderManager.h b/kraken/KRShaderManager.h
index 5339b6e..dd8e15b 100644
--- a/kraken/KRShaderManager.h
+++ b/kraken/KRShaderManager.h
@@ -61,7 +61,24 @@ public:
 
   unordered_map<std::string, unordered_map<std::string, KRShader*> >& getShaders();
 
+  class Includer : public glslang::TShader::Includer
+  {
+  public:
+    Includer() = delete;
+    Includer(KRContext* context);
+    IncludeResult* includeSystem(const char* headerName,
+                                 const char* includerName,
+                                 size_t inclusionDepth) override;
+    IncludeResult* includeLocal(const char* headerName,
+                                const char* includerName,
+                                size_t inclusionDepth) override;
+    void releaseInclude(IncludeResult* includeResult) override;
+  private:
+    KRContext* m_context;
+  };
+
 private:
   unordered_map<std::string, unordered_map<std::string, KRShader*> > m_shaders;
   bool m_initializedGlslang;
+  Includer m_includer;
 };
diff --git a/standard_assets/shaders/CMakeLists.txt b/standard_assets/shaders/CMakeLists.txt
index b84ae0e..311589e 100644
--- a/standard_assets/shaders/CMakeLists.txt
+++ b/standard_assets/shaders/CMakeLists.txt
@@ -7,3 +7,4 @@ add_standard_asset(vulkan_test.vert)
 add_standard_asset(vulkan_test.frag)
 add_standard_asset(debug_font.vert)
 add_standard_asset(debug_font.frag)
+add_standard_asset(vulkan_test_include.glsl)
diff --git a/standard_assets/shaders/vulkan_test.vert b/standard_assets/shaders/vulkan_test.vert
index c26d016..fe543c9 100644
--- a/standard_assets/shaders/vulkan_test.vert
+++ b/standard_assets/shaders/vulkan_test.vert
@@ -1,4 +1,7 @@
 #version 450
+#extension GL_GOOGLE_include_directive : enable
+
+#include "vulkan_test_include.glsl"
 
 // Temporary test shader for vulkan bringup...
 // See https://vulkan-tutorial.com/Drawing_a_triangle/Graphics_pipeline_basics/Shader_modules
@@ -17,5 +20,5 @@ layout( push_constant ) uniform constants
 
 void main() {
     gl_Position = vec4(vertex_position * 0.5, 1.0);
-    fragColor = vertex_normal * 0.25 + vec3(0.5, 0.5, 0.5);
+    fragColor = vertex_normal * 0.25 + vec3(0.5, 0.5, 0.5) * VULKAN_TEST_BRIGHTNESS;
 }
diff --git a/standard_assets/shaders/vulkan_test_include.glsl b/standard_assets/shaders/vulkan_test_include.glsl
new file mode 100644
index 0000000..2661c45
--- /dev/null
+++ b/standard_assets/shaders/vulkan_test_include.glsl
@@ -0,0 +1,2 @@
+
+#define VULKAN_TEST_BRIGHTNESS 0.25