diff --git a/packages/typescript/internal/build_defs.bzl b/packages/typescript/internal/build_defs.bzl
index 942f49c3a0..fc425c2fa6 100644
--- a/packages/typescript/internal/build_defs.bzl
+++ b/packages/typescript/internal/build_defs.bzl
@@ -104,7 +104,7 @@ def _filter_ts_inputs(all_inputs):
     return [
         f
         for f in all_inputs
-        if f.extension in ["js", "jsx", "ts", "tsx", "json"]
+        if f.extension in ["js", "jsx", "ts", "tsx", "json", "proto"]
     ]
 
 def _compile_action(ctx, inputs, outputs, tsconfig_file, node_opts, description = "prodmode"):