I want to build an app that inserts the same code (.js, .css or .liquid) in different Shopify stores that require the same, and not have to put that code one by one.
Any suggestions on what components work for it? Or do you know if it is possible to do?
1. use your partner account to get a pair of App install API keys designated as a Public App, allowing one App to be installed in many stores
2. create an App that provides your .js, .css and or .liquid assets using the provided API keys
3. Profit, once Shopify allows this App to exist and be installed in merchant stores
Shopify has published more documentation on how to do this and provides more free open source software to do this, than almost any other comparable company. You are free to take advantage and profit, like a million other people. That, will help you a lot.