[very common; back-formation from crufty]

1. n. An unpleasant substance. The dust that gathers under your bed is cruft; the TMRC Dictionary correctly noted that attacking it with a broom only produces more.

2. n. The results of shoddy construction.

3. vt. [from hand cruft, pun on ‘hand craft’] To write assembler code for something normally (and better) done by a compiler (see hand-hacking).

4. n. Excess; superfluous junk; used esp. of redundant or superseded code.

5. [University of Wisconsin] n. Cruft is to hackers as gaggle is to geese; that is, at UW one properly says “a cruft of hackers”.