Verc allows you to automatically update your global .npmrc file with multiple registries.
You can install verc globally and use it as a command line.
yarn
yarn global add verc
npm
npm -G install verc
Verc is friends with the postinstall lifecycle hook.
You can hook it into your projects to automatically update packages for you:
{
"name": "my-important-project",
"scripts": {
"postinstall": "verc update"
}
}