cruft: /kruhft/ [back-formation from {crufty}] 1. n.

:cruft: /kruhft/ [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 of redundant or superseded code.

This term is one of the oldest in the jargon and no one is sure of
its etymology, but it is suggestive that there is a Cruft Hall at
Harvard University which is part of the old physics building; it's
said to have been the physics department's radar lab during WWII.
To this day (early 1993) the windows appear to be full of random
techno-junk. MIT or Lincoln Labs people may well have coined the
term as a knock on the competition.
-- The AI Hackers Dictionary