diff --git a/base/stringutil.h b/base/stringutil.h
index 59b1d0d03d..7cc61b3086 100644
--- a/base/stringutil.h
+++ b/base/stringutil.h
@@ -34,3 +34,22 @@ inline void StringToHexString(const std::string &data, std::string *output) {
 
 // highly unsafe and not recommended.
 unsigned int parseHex(const char* _szValue);
+
+
+// Suitable for inserting into maps, unlike char*, and cheaper than std::string.
+// Strings must be constant and preferably be stored in the read-only part 
+// of the binary.
+class ConstString {
+public:
+  ConstString(const char *ptr) {
+    ptr_ = ptr;
+  }
+  bool operator <(const ConstString &other) const {
+    return strcmp(ptr_, other.ptr_) < 0;
+  }
+  bool operator ==(const ConstString &other) const {
+    return ptr_ == other.ptr_ || !strcmp(ptr_, other.ptr_);
+  }
+private:
+  const char *ptr_;
+};
diff --git a/gfx_es2/glsl_program.h b/gfx_es2/glsl_program.h
index 58392f64d2..2d5f0adc0a 100644
--- a/gfx_es2/glsl_program.h
+++ b/gfx_es2/glsl_program.h
@@ -16,6 +16,7 @@
 #endif
 #endif
 
+#include <map>
 #include <time.h>
 
 #include "gfx/gl_lost_manager.h"
@@ -54,6 +55,9 @@ struct GLSLProgram : public GfxResourceHolder {
   void GLLost();
 };
 
+
+// C API, old skool
+
 GLSLProgram *glsl_create(const char *vshader_file, const char *fshader_file);
 void glsl_destroy(GLSLProgram *program);