diff --git a/shaders/simple.vert b/shaders/simple.vert
index 7dad78c..7eb80e9 100644
--- a/shaders/simple.vert
+++ b/shaders/simple.vert
@@ -3,7 +3,7 @@
 in layout(location=0) vec3 position;
 in layout(location=1) vec4 aColor;
 out vec4 vColor;
-uniform mat4 transform;
+layout(location = 0) uniform mat4 transform;
 
 void main() {
     gl_Position = transform * vec4(position, 1.0f);