yes its rust. Looks like you're right. Well is back to good old emacs for me!
What kind of emacs scripts do you write to help debug Rust?
Then I have a bunch of elisp code that calls just and / or generates boilerplate code right in the buffer - M-x new-macro or M-x run-test (asks for a test to run) etc. I keep writing more elisp as I go along and add specific key bindings to specific things and now its too hard to move away from it all.