diff --git a/kitty/shaders.c b/kitty/shaders.c
index 1e894fbb1..0cd6c2d77 100644
--- a/kitty/shaders.c
+++ b/kitty/shaders.c
@@ -13,6 +13,7 @@
 #include <GL/glew.h>
 #endif
 
+static char glbuf[4096];
 
 // GL setup and error handling {{{
 // Required minimum OpenGL version
@@ -20,6 +21,14 @@
 #define REQUIRED_VERSION_MINOR 3
 #define GLSL_VERSION (REQUIRED_VERSION_MAJOR * 100 + REQUIRED_VERSION_MINOR * 10)
 
+#ifndef GL_STACK_UNDERFLOW
+#define GL_STACK_UNDERFLOW 0x0504
+#endif
+
+#ifndef GL_STACK_OVERFLOW
+#define GL_STACK_OVERFLOW 0x0503
+#endif
+
 static inline bool
 set_error_from_gl() {
     int code = glGetError();
@@ -69,10 +78,10 @@ glew_init(PyObject UNUSED *self) {
 }
 // }}}
 
+// Programs {{{
 enum Program { CELL_PROGRAM, CURSOR_PROGRAM, BORDERS_PROGRAM, NUM_PROGRAMS };
 
 static GLuint program_ids[NUM_PROGRAMS] = {0};
-static char glbuf[4096];
 
 static inline GLuint
 compile_shader(GLenum shader_type, const char *source) {
@@ -94,6 +103,8 @@ compile_shader(GLenum shader_type, const char *source) {
     }
     return shader_id;
 }
+// }}}
+
 
 // Python API {{{
 static PyObject*
@@ -138,7 +149,7 @@ end:
     Py_RETURN_NONE;
 }
 
-#define M(name, arg_type) {#name, (PyCFunction)name, arg_type, ""}
+#define M(name, arg_type) {#name, (PyCFunction)name, arg_type, NULL}
 static PyMethodDef module_methods[] = {
     M(enable_automatic_opengl_error_checking, METH_O),
     {"glewInit", (PyCFunction)glew_init, METH_NOARGS, NULL}, 
diff --git a/kitty/shaders.py b/kitty/shaders.py
index f2c62a974..b55c1e9b8 100644
--- a/kitty/shaders.py
+++ b/kitty/shaders.py
@@ -37,8 +37,8 @@ BASE = os.path.dirname(os.path.abspath(__file__))
 
 @lru_cache()
 def load_shaders(name):
-    vert = open(os.path.join(BASE, '{}_vertex.glsl'.format(name))).read()
-    frag = open(os.path.join(BASE, '{}_fragment.glsl'.format(name))).read()
+    vert = open(os.path.join(BASE, '{}_vertex.glsl'.format(name))).read().replace('GLSL_VERSION', str(GLSL_VERSION), 1)
+    frag = open(os.path.join(BASE, '{}_fragment.glsl'.format(name))).read().replace('GLSL_VERSION', str(GLSL_VERSION), 1)
     return vert, frag
 
 
@@ -244,11 +244,7 @@ class ShaderProgram:  # {{{
         Create a shader program.
 
         """
-        self.program_id = compile_program(
-            which,
-            vertex.replace('GLSL_VERSION', str(GLSL_VERSION), 1),
-            fragment.replace('GLSL_VERSION', str(GLSL_VERSION), 1)
-        )
+        self.program_id = compile_program(which, vertex, fragment)
         self.vertex_arrays = {}
 
     @contextmanager