The same author also wrote Janet, which is also a nice language from what I’ve played around with. Especially the idea of forgoing Regex entirely and going with PEGs, as well as having “defs” inside functions bind local variables instead of “let” (though let is also idiomatic), very interesting. Small languages like that give a very nice feeling of learning them in a single day.
I looked into that language for exactly that reason and like it quite a lot. It's very good for scripting, though that is a crowded niche these days. It's also not much harder to integrate than lua, so I've used it a few times for an integrated scripting language when I didn't actually need a teeny tiny runtime.
And yeah you end up really missing PEGs in other languages. There are libraries, but having it built in is another thing especially with how well they fit into s-exp syntax.
