Earlier quoted context omitted.
Ruby is fantastic for the main project language, too! And is also standard on many Linux distros.
Ruby's fine for small to medium-sized projects. It's pretty great for small DSLs. In my professional experience on medium to large-sized projects, its lack of explicit typing, the habit of Rubyists to use its fairly-substantial metaprogramming capabilities at the drop of a hat, and (for projects that include pieces or all of Rails) the system's implicit library loading make such projects a nightmare to reason about a…
Contrast that with gitlab-runner (Go) or VSCode (Typescript) both of which I have been able to not only read easily but contribute features to. VSCode is at least as big a codebase as Gitlab.
That experience has made me want to avoid Ruby like the plague!