This was Andrew Schultz's 2016 Ectocomp game. The author has made a mini-game, kind of reminiscent of one of the hat puzzle games (maybe Playing Games?) with a sort of maze you need to trace out, through 5 different levels.
The fifth level is different than the other levels. It needs a special command to finish it. The more times you replay it, the more hints that you get as to what the command is.