I have recently gotten access to lightscale.ai, which is still in private beta, and I'm impressed.

They have a different approach to lovable, replit, etc... They don't let the gpt models translate directly into program code, but into an intermediate language which is then compiled by a compiler. Generation speed is blazingly fast, and so far results look great.

I really like that I can work on an app without having to wait between my prompts and can see the results nearly instantly.

Apparently it's safer too, as code generation is deterministic. But I did not check that yet, as I only recently got access.