The app depends on highlight.js which currently supports a limited set of languages, and unfortunately, Brainfuck isn't one of them.

http://softwaremaniacs.org/media/soft/highlight/test.html

I wonder what would happen to the accuracy of highlight.js highlightAuto method if more languages were to be supported. Highlight.js recognizes languages based on how many language constructs it can recognize. More languages = more overlap in language constructs, and therefore more likelihood of wrong matches.