Platypus generates Mac apps from command line tools
Platypus lets you wrap a command line tool with a native macOS app with ease. It gives you several different types of user interface.
This isn’t going to be replacing Electron any time soon, but for quickly wrapping a command line tool, this seems hard to beat.
I found this via a Hacker News discussion about Suitcase, which looks promising for creating more-customizable UIs, but is less full-featured than Platypus in other ways.