cruft

What does cruft mean?

Cruft refers to unwanted/unnecessary/leftover/useless stuff, aka “junk,” and is used mainly in the context of computers, coding, software, video games, etc.

Examples of cruft

I have upgraded through several releases over the years and my /etc/config directory has gained some cruft. Some haven’t been touched for over seven years!
—@N0NB, Reddit, 17 Feb. 2023

Somewhat more behind the scenes are so-called embedded devices: set-top boxes, home routers, smart television sets, gaming consoles and even quite a few refrigerators, all running a descendant of Unix. But tucked within the sprawling bits of code in these gizmos is a great deal of cruft—vestigial programs and routines that perhaps have no function in a router or a smartphone, but that ostensibly are not doing any harm.
—The Economist, 24 Oct. 2014

The word sources are not perfect, but they are not full of the usual cruft that accumulates in the majority of public-domain wordlists.
—Rex Gooch, Word Ways, 1 Aug. 2004

There is a a lot of cruft in this game. They even break their own Nintendo “Rule of Three” by having you do FOUR back-to-back fetch quests of little consequences.
—@carygolomb, X (formerly Twitter), 23 July 2025

Where does cruft come from?

In An Abridged Dictionary of the TMRC [Tech Model Railroad Club of M.I.T.] Language written by Peter R. Samson in 1959, cruft is defined as “that which magically amounds in the Clubroom just before you walk in to clean up. In other words, rubbage.” Samson himself notes that “The word was in use at the club when I wrote this definition. The sense is of detritus, that which needs to be swept up and thrown out.”

Given the similarities in meaning between the TMRC’s coinage and the computer-related use of cruft (and the TMRC dictionary’s inclusion of another word, hacker, now associated with computing), the two could be linked. Regardless, the computer cruft was used originally for poorly constructed or unnecessary computer code before broadening in meaning.

It was nearly impossible to tell the working code from cruft, Kent said.
—John Sundman, Salon, 21 Oct. 2003

How is cruft used?

One related term with some possible overlap is bloatware. Like bloatware and slop, cruft tends to get invoked out of frustration and annoyance.

Cruft has also spawned an adjective, crufty:

I’ve been updating the crufty old code I use to generate graphs to help me (and colleagues) think about river flows.
—John Fleck, Inkstain.net, 2 Feb. 2024