Author here, thank you! The reason I stated that Melody is unstable is that the project is very young (days) and so some of the syntax is still being considered and may change (although the general idea and direction will remain), and also not everything is implemented yet. I'm also considering changing the way the parsing works but that wouldn't affect end users in terms of expected results for valid code)

Even as someone who has invested time in learning to write regexp, they are still hard to read and maintain. This project looks super cool!

You could learn it in a few hours. There aren't many rules.

Just use one of the many generators

manual: https://regexr.com/

AI: https://regex-generator.olafneumann.org/

I'm a big fan of https://rubular.com.