- have a SQL(lite) mode, using https://sql.js.org/#/
- have a basic C/C++ mode ! See https://github.com/felixhao28/JSCPP/
- have a basic OCaml mode ! See https://github.com/ocsigen/js_of_ocaml and https://github.com/jbdo99/BetterOCaml/
It would be awesome to lots of students in France (and elsewhere!).