diff --git a/arcade/context.py b/arcade/context.py
index e86297cfa..060f756d8 100644
--- a/arcade/context.py
+++ b/arcade/context.py
@@ -385,6 +385,8 @@ def load_program(
         from arcade.resources import resolve
 
         vertex_shader_src = resolve(vertex_shader).read_text()
+        vertex_shader_src = self.shader_inc(vertex_shader_src)
+
         fragment_shader_src = None
         geometry_shader_src = None
         tess_control_src = None