This is an emacs mode for editing Idris code. This mode was original designed to work with version 1 of the language through an IDE-Protocol. Idris2 uses the next iteration of the same protocol. Idris-mode tries to maintain compatibility with both protocol versions, however, not all the features from the IDE-Protocol have been realised in Idris2. When using idris-mode with Idris2 your experience might be a bit clunky. idris-hackers/idris-mode