What's the best SaaS boilerplate/all in one solution to build a PoC/MVP?

I often want to try out some products ideas, and setting up a whole project is always a real PITA: auth, payments, db, hosting, analytics, support etc...

I'm wondering if there is any good software (whether it's open source or on a freemium/per usage pricing), that allows you to just work on your features and nothing else, basically copy/paste a few API keys, write an API route, a react form and a view, and you have a working product.

I tried some open source boilerplates on github, but they weren't up to the task, either outdated and bugged or way too complex and badly written and it was a pain to add anything.

I'm mostly looking for something made with typescript/node or that is language agnostic