Hello Odinachi, CASE (https://case.app) is also an Open Source alternative to Firebase. It's a lightweight BaaS in Typescript.

Thanks for your post Ritesh, We just launched https://case.app, another open source alternative to those ones above. It is lightweight and pro-code (no-no-code), have a look !

Hello Carlos, (Founder of CASE here): We just launched a self-hosted open source BaaS named CASE: https://case.app. It is an alternative to the providers mentioned above with en emphasis on code instead of going to menus. Check it out !