Thank you for explaining, I only know nonce being used to refer to someone as a pedo so Noncefest certainly raised an eyebrow. I can only assume this guy was unaware of the meaning.

As someone from the UK who works in software engineering, the combination of meanings is always hilarious

thank you i had to look up the british slang now, as I could only think of the cryptographic association

nonce did used to be an English word too meaning "of/at the moment" or "for one purpose" so Number used Once is actually a backronym

It derived from Middle English was "tō þen naness" which is roughly "best item for a purpose" literally, but is used to mean "something" or "disposable/temporary" in context.

Am from the UK and my mom would call anyone she didnt like on TV a nonce (turns out she had a high accuratarcy rate) so i grew up thinking it just meant stupid, which resulted in me calling myself a nonce when making a mistake at work to peoples shock and amusment.

cryptography (not the cryptocurrency-kind)

This may be pedantic, but that is the cryptocurrency kind. The "crypto" in "cryptocurrency" literally comes from the term "cryptography". It is currency that is secured by cryptographic functions.

See, I never knew that. I wondered what kind of weird convention this is. 😂

Very related to this