diff --git a/build_12.zig b/build_12.zig
index ff534c8b5..54fd29110 100644
--- a/build_12.zig
+++ b/build_12.zig
@@ -28,7 +28,7 @@ pub fn build_12(b: *Build) void {
 
     const webui = build_webui_12(b, optimize, target, isStatic, enableTLS);
 
-    webui.installHeader("include/webui.h", "webui.h");
+    webui.installHeader(b.path("include/webui.h"), "webui.h");
 
     build_examples_12(b, optimize, target, webui);