diff --git a/src/build.rs b/src/build.rs
index 02566e2..accc8de 100644
--- a/src/build.rs
+++ b/src/build.rs
@@ -44,8 +44,9 @@ pub fn create_static_output_files(source_dir: &str) {
       }
     }
     Err(err) => {
-      if err.kind() != NotFound {
-        panic!("Unexpected error: {}", err)
+      if err.kind() == NotFound {
+      } else {
+        Err(err).unwrap();
       }
     }
   }