diff --git a/rslib/io/src/lib.rs b/rslib/io/src/lib.rs
index cb44467e6..fc366b69c 100644
--- a/rslib/io/src/lib.rs
+++ b/rslib/io/src/lib.rs
@@ -335,6 +335,15 @@ pub fn write_file_if_changed(path: impl AsRef<Path>, contents: impl AsRef<[u8]>)
             .map(|existing| existing != contents)
             .unwrap_or(true)
     };
+
+    match std::env::var("CARGO_PKG_NAME") {
+        Ok(pkg) if pkg == "anki_proto" || pkg == "anki_i18n" => {
+            // at comptime for the proto /i18n crates, register implicit output as output
+            println!("cargo:rerun-if-changed={}", path.to_str().unwrap());
+        }
+        _ => {}
+    }
+
     if changed {
         write_file(path, contents)?;
         Ok(true)