I mean, you have to justify being stuck somehow. While GitLab is certainly not an average Rails project technical debt-wise (I'm a tiny-time contributor to GitLab and my experience was quite amazing), but it's still Rails & Ruby all the way down there which could get you going only so much. You still have to write shitloads of tests, most of which are doing a sum-types-able programming language compiler's job over and over again. One day you realize this and that's the day Ruby is dead for you because there's no chance in hell you can persuade your peers to use measly dry-rb (dry-rb maintainers — no offense, I'm admiring your stellar work), not to mention moving to F#/Ocaml/Haskell/Rust.