Every so often some question on SO is just a rant about Xcode and says something like "the worst IDE ever created" and I'm just floored thinking what a tiny slice of our history this person must have experienced. They've tried a few IDEs from JetBrains and think they've sampled the world?
Come with me, summer child, into the world of Qualcomm firmware IDEs. Custom IDEs built by Nortel. The cult classic of USCD Pascal (with its admittedly primitive glory, but you don't want it to replace Xcode).