essence-of-live-coding-tutorial$ ghcid
Loading cabal repl -O2 ...
cabal: unrecognized 'repl' option `-O2'
Command "cabal repl -O2" exited unexpectedly with error message: cabal: unrecognized 'repl' option `-O2'
When I start cabal repl myself, I encounter no problems and see the white ball in a black window that somehow reacts to mouse clicks and moves. Is ghcid required for the tutorial?