`pglite` is a WASM version of postgres. I use it in one of my side projects for providing a postgres DB running in the user's browser.

For most purposes, it works perfectly fine, but with two main caveats:

1. It is single user, single connection (i.e. no MVCC) 2. It doesn't support all postgres extensions (particularly postGIS), though it does support pgvector

https://github.com/supabase-community/pg-gateway is something that may be used to use pglite for prototyping I guess, but I haven't used this.