This isn’t really relevant to Atom, but... Emacs is working on this, on several fronts. In many ways, this isn’t (yet) an improvement, because what we have now

This isn’t really relevant to Atom, but... Emacs is working on this, on several fronts. In many ways, this isn’t (yet) an improvement, because what we have now are a bunch of partial implementations that mostly get different parts ‘right’. On the other hand, progress. TBH, one of the big stumbling blocks is that a lot of the most adept Emacs hackers simply don’t do much of the sort of ‘IDE-grade’ stuff, so in a real sense, they don’t understand what they (and Emacs) are missing. (Fair cop: I’m largely in this boat myself.) For example, Emacs has had dynamic adaptive customizable electric hippie completion for longer than there has been a publicly released Java language, BUT many (is it still most? My experience is old) Emacs hackers just never did the sort of refactoring that made people tolerate Eclipse — and that was over a decade ago. One more thing: if you are interested in lisp, can stand to see C code, and are interested in LSP, look at Emacs-devel.