I will take any of the dozen of sometimes very large compilers written in Ocaml above rustc personally but to each their own.
But also, the editor plugins don't work on the compiler itself? Why's that? So you can't use Merlin on the OCaml compiler? That doesn't seem great.
And what's with the syntax highlighting being funky? The highlighter appears to think that a lot of these files have unterminated comments or string literals.