diff --git a/serde_tests/build.rs b/serde_tests/build.rs
index 81f5c41f..6e1c1ff8 100644
--- a/serde_tests/build.rs
+++ b/serde_tests/build.rs
@@ -13,10 +13,6 @@ fn main() {
     ] {
         let src = Path::new(src);
         let dst = Path::new(&out_dir).join(dst);
-
-        let mut registry = syntex::Registry::new();
-
-        serde_codegen::register(&mut registry);
-        registry.expand("", &src, &dst).unwrap();
+        serde_codegen::expand(&src, &dst).unwrap();
     }
 }