I remember seeing "cruft" in the Hacker Dictionary back in the mid-80's but didn't start using it in everyday conversation until I started working in tech and hanging out with MIT folk in 1992. At the time, I was told there was cruft (which was dry fodder, dust, papers, etc.) and spooge, which was wet, greasy, or grimy. I believe there was some discussion of how there could be crufty spooge, but in general, once spooge enters the equation it supersedes cruft.

I use outcrufting rather than decrufting, but I've heard both used for years.