Ask HN: If building an IDE from scratch, what features would you add?

Great debugging capabilities, time travel debugging, data break points, attach to running processes, remote debugging etc.

I think the most important feature for an IDE is debugging - at least this is the feature which separates an ide from just a Text Editor

Native vector search would be great. I was just thinking today how irritating it is to try to find some specific component in a very large codebase without knowing exactly what it’s called already.

You mean like Zed? Check their roadmap.

I'd keep all the features from neovim, remove all the features from every other IDE.