There are many Emacs packages and modules for Haskell. haskell-mode is stable and usable, whereas lsp-haskell is newer but under development and not ready for general use. Newbie guide Emacs is an extensible texteditor which can be extended with so-called "modes" and makes great use of keystrokes. Modes are written in Emacs Lisp (.el) programming language and provide additional commands and keystr