> I always thought it would be cool to have a PC that you just turn on and in 200 milliseconds, you're at a Python REPL or something

That is where I plan to go with SPADE, https://hackage.haskell.org/package/spade

As you can see, it is currently written in Haskell, as a PoC. But I am re-writing it in Rust, for reasons that also include making it possible to do something like you ask for.