diff --git a/scala_proto/private/proto_to_scala_src.bzl b/scala_proto/private/proto_to_scala_src.bzl
index 58d565fe3..b3f7727de 100644
--- a/scala_proto/private/proto_to_scala_src.bzl
+++ b/scala_proto/private/proto_to_scala_src.bzl
@@ -4,24 +4,20 @@ load(
 )
 load("//scala/private:rule_impls.bzl", "compile_scala")
 
-
 def _root_path(f):
     if f.is_source:
         return f.owner.workspace_root
     return "/".join([f.root.path, f.owner.workspace_root])
 
-
 def _colon_paths(data):
     return ":".join([
         f.path
         for f in sorted(data)
     ])
 
-
 def encode_named_generators(named_generators):
     return ",".join([k + "=" + v for (k, v) in sorted(named_generators.items())])
 
-
 def proto_to_scala_src(ctx, label, code_generator, compile_proto, include_proto, transitive_proto_paths, flags, jar_output, named_generators, extra_generator_jars):
     worker_content = "{output}\n{included_proto}\n{flags_arg}\n{transitive_proto_paths}\n{inputs}\n{protoc}\n{extra_generator_pairs}\n{extra_cp_entries}".format(
         output = jar_output.path,
@@ -33,8 +29,8 @@ def proto_to_scala_src(ctx, label, code_generator, compile_proto, include_proto,
         # Pass inputs seprately because they doesn't always match to imports (ie blacklisted protos are excluded)
         inputs = _colon_paths(compile_proto),
         protoc = ctx.executable._protoc.path,
-        extra_generator_pairs= "-" + encode_named_generators(named_generators),
-        extra_cp_entries = "-" + _colon_paths(extra_generator_jars)
+        extra_generator_pairs = "-" + encode_named_generators(named_generators),
+        extra_cp_entries = "-" + _colon_paths(extra_generator_jars),
     )
     argfile = ctx.actions.declare_file(
         "%s_worker_input" % label.name,
@@ -44,11 +40,10 @@ def proto_to_scala_src(ctx, label, code_generator, compile_proto, include_proto,
     ctx.actions.run(
         executable = code_generator.files_to_run,
         inputs = compile_proto + include_proto + [argfile, ctx.executable._protoc] + extra_generator_jars,
+        tools = compile_proto,
         outputs = [jar_output],
         mnemonic = "ProtoScalaPBRule",
         progress_message = "creating scalapb files %s" % ctx.label,
         execution_requirements = {"supports-workers": "1"},
         arguments = ["@" + argfile.path],
     )
-
-