[brundolf]

The answer to this kind of question is always "whatever you're most comfortable/productive with"

For me personally, I've been working on one that's pretty app-y and used Postgres + Deno + React/MobX (built with esbuild)

I'm very comfortable and happy with TypeScript, so I like having it on both ends (especially because I can share types between the two sides of the wire). And Deno and esbuild make the tooling story really simple and no-nonsense on the back and the front respectively, while being less opinionated than a framework like Next (I like Next for other things, just didn't choose it here)

[zamerick]

This, with the added mention that if you intend to turn this into a business and hire people, choose something that is easy to hire for.