We are using LSP under the hood, but you can't add more language servers yourself. AS for DAP, a debugger would be a huge feature to implement, we wanted to get it right before releasing it.

Interesting! Do you have any plans to open support for LSPs? I do see the appeal to having a totally curated list of LSPs you don't have to worry about, but if someone buys into this editor, it might be nice to be able to extend it with new language support in the future so you don't have to switch editors for different languages.