There are a few similar open source projects, like Tic-80 and Liko-12. Both can be programmed with Lua, but Tic-80 can also be programmed with others like Javascript and Wren and the porting process can be fairly simple.
I used NICO before which is programmed in Nim:
Being Nim-based means the result can be compiled to C or JavaScript, so it can run at native speed or in the browser.