Projects like these should be celebrated through donations and this project makes it easy. When’s the last time you’ve seen freeware developer tool for macOS that’s not from a corporation with money to spare?
I personally can’t think of anything beyond iTerm (utility), Homebrew (utility), ...aaand that's where my list ends.
cyberduck, iina, adium, notational velocity, divvy, hex fiend, keka, xee, unicodechecker, textual, …
That's just a subset of what I saw scanning my /Applications, and I don't specifically look out for replacing existing software with free (whether freedom or beer) applications.
> divvy, textual
Neither of these are freeware?
Textual is open source https://github.com/Codeux-Software/Textual