diff --git a/bazel/api-golden/BUILD.bazel b/bazel/api-golden/BUILD.bazel
index f0cd3fc42..b784a7a70 100644
--- a/bazel/api-golden/BUILD.bazel
+++ b/bazel/api-golden/BUILD.bazel
@@ -4,14 +4,14 @@ package(default_visibility = ["//visibility:public"])
 
 exports_files([
     "index.ts",
-    "index_npm_packages.ts",
+    "index_npm_packages.cts",
 ])
 
 ts_project(
     name = "api-golden",
     srcs = [
         "find_entry_points.ts",
-        "index_npm_packages.ts",
+        "index_npm_packages.cts",
         "interop_module_mappings.ts",
         "path-normalize.ts",
         "test_api_report.ts",
diff --git a/bazel/api-golden/find_entry_points.ts b/bazel/api-golden/find_entry_points.ts
index f442005a9..ce24ca364 100644
--- a/bazel/api-golden/find_entry_points.ts
+++ b/bazel/api-golden/find_entry_points.ts
@@ -9,7 +9,7 @@
 import {dirname, join, relative} from 'path';
 import {lstatSync, readFileSync, readdirSync} from 'fs';
 
-import {PackageJson} from './index_npm_packages.js';
+import {PackageJson} from './index_npm_packages.cjs';
 
 /** Interface describing a resolved NPM package entry point. */
 export interface PackageEntryPoint {
diff --git a/bazel/api-golden/index_npm_packages.ts b/bazel/api-golden/index_npm_packages.cts
similarity index 100%
rename from bazel/api-golden/index_npm_packages.ts
rename to bazel/api-golden/index_npm_packages.cts
diff --git a/bazel/api-golden/index_rjs.bzl b/bazel/api-golden/index_rjs.bzl
index e3d7680ce..4a91f5c4d 100644
--- a/bazel/api-golden/index_rjs.bzl
+++ b/bazel/api-golden/index_rjs.bzl
@@ -42,7 +42,7 @@ def api_golden_test_npm_package(
     js_test(
         name = name,
         data = data,
-        entry_point = "@devinfra//bazel/api-golden:index_npm_packages.js",
+        entry_point = "@devinfra//bazel/api-golden:index_npm_packages.cjs",
         args = [golden_dir, npm_package, "false", quoted_export_pattern] + type_names,
         env = {"RJS_MODE": "true" if not interop_mode else "false"},
         **kwargs
@@ -52,7 +52,7 @@ def api_golden_test_npm_package(
         name = name + ".accept",
         testonly = True,
         data = data,
-        entry_point = "@devinfra//bazel/api-golden:index_npm_packages.js",
+        entry_point = "@devinfra//bazel/api-golden:index_npm_packages.cjs",
         args = [golden_dir, npm_package, "true", quoted_export_pattern] + type_names,
         # TODO: Determine why this is needed but only for this `.accept` action
         #       https://github.com/angular/dev-infra/issues/2742