The 29th International Obfuscated C Code Contest (IOCCC) 2025 Winners

The GameBoy emulator's code also looks like the GameBoy. Slow clap this is insane, definitely my favorite entry.

The author, Nick Craig-Wood, is the creator of rclone!

	▲	sourcecodeplz 32 minutes ago \| parent [-]
		Damn, that is cool! Looking at me typing css & php...

aquir an hour ago | parent | prev | next [-]

The website itself is obfuscated, it’s not easy to find the C sources at all!

	▲	lifebeyondfife 26 minutes ago \| parent [-]
		Can jump straight to https://www.ioccc.org/2025/#inventory

rurban 9 minutes ago | parent | prev | next [-]

So like at a film festival, 90% of the entries won a price, but unlike a film festival there's not a single best. Weird, like modern education.

larodi an hour ago | parent | prev [-]

Tis a pity to not have LLMs compete, given level of obfuscation they be capable of.

	▲	lifthrasiir 24 minutes ago \| parent \| next [-]
		In my experience LLMs were pretty good at deobfuscating many entries (including mine) but very awful at generating any significantly obfuscated code. So obfuscation can be regarded as a truly humane art---at least for now.
	▲	AlotOfReading 6 minutes ago \| parent \| prev [-]
		It's a bit annoying getting frontier models to even work on IOCCC code because of "safety", but even if you get around that LLMs just aren't very good at it. Obfuscating code involves a level of creativity and deviousness that LLMs struggle to meet.