It's really maddening to write 50,000 lines of code, eventually get it
to compile, run it, and have the program lock up and start consuming so
much virtual memory that the entire PC becomes unstable within seconds.

(This isn't helped by the fact that Ctrl+C doesn't seem to make either
GHCi or GHC-compiled programs halt...) Now you have 50,000 lines of
otherwise untested code, and there's a bug within it *somewhere*... good
luck.