Funny story: The way my compiler ( https://github.com/neat-lang/neat ) used to build is, three years ago there was an initial minimal compiler that was written in D. And every time you checked out the Neat repo on a new system, it had a file with a list of breaking commits, and it would:

- git clone itself in a subfolder

- git checkout and build the initial D compiler

- install it in a temporary prefix

- git checkout the first breaking commit and build it with the initial compiler

- install it over the previous compiler

- git checkout ...

and so on. In normal operation all these stages would be cached, so before I abandoned this approach, I think I was up to a hundred or so intermediate versions.

Eventually I started doing git releases, which needed a better solution. So since I have an optional C backend, I just build the compiler with the C backend, then zip up all the C files to make the release. Then to bootstrap from it, I just do (effectively) gcc *.c -o build/neat_bootstrap.

edit: Ah, here it is: https://github.com/Neat-Lang/neat/blob/v0.1.6/bootstrap.sh