diff --git a/packages/browsers/package.json b/packages/browsers/package.json
index 2799fad34d6..9934bb44a96 100644
--- a/packages/browsers/package.json
+++ b/packages/browsers/package.json
@@ -23,7 +23,7 @@
   },
   "wireit": {
     "build": {
-      "command": "tsc -b && chmod a+x lib/cjs/main-cli.js lib/esm/main-cli.js",
+      "command": "tsc -b && tsx ../../tools/chmod.ts 755 lib/cjs/main-cli.js lib/esm/main-cli.js",
       "files": [
         "src/**/*.ts",
         "tsconfig.json"
diff --git a/packages/puppeteer-core/package.json b/packages/puppeteer-core/package.json
index 81fdf61721b..2d62fbc69a8 100644
--- a/packages/puppeteer-core/package.json
+++ b/packages/puppeteer-core/package.json
@@ -46,7 +46,7 @@
   },
   "wireit": {
     "prepack": {
-      "command": "cp ../../README.md README.md",
+      "command": "tsx ../../tools/cp.ts ../../README.md README.md",
       "files": [
         "../../README.md"
       ],
diff --git a/packages/puppeteer/package.json b/packages/puppeteer/package.json
index 3fed4478955..1157b4dca73 100644
--- a/packages/puppeteer/package.json
+++ b/packages/puppeteer/package.json
@@ -42,7 +42,7 @@
   },
   "wireit": {
     "prepack": {
-      "command": "cp ../../README.md README.md",
+      "command": "tsx ../../tools/cp.ts ../../README.md README.md",
       "files": [
         "../../README.md"
       ],
diff --git a/tools/chmod.ts b/tools/chmod.ts
new file mode 100644
index 00000000000..89afe0f9e7d
--- /dev/null
+++ b/tools/chmod.ts
@@ -0,0 +1,27 @@
+/**
+ * Copyright 2023 Google Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import fs from 'fs';
+
+/**
+ * Calls chmod with the mode in argv[2] on paths in argv[3...length-1].
+ */
+
+const mode = process.argv[2];
+
+for (let i = 3; i < process.argv.length; i++) {
+  fs.chmodSync(process.argv[i], mode);
+}
diff --git a/tools/cp.ts b/tools/cp.ts
new file mode 100644
index 00000000000..438c6ccd547
--- /dev/null
+++ b/tools/cp.ts
@@ -0,0 +1,22 @@
+/**
+ * Copyright 2023 Google Inc. All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import fs from 'fs';
+
+/**
+ * Copies single file in argv[2] to argv[3]
+ */
+fs.cpSync(process.argv[2], process.argv[3]);