The 29th International Obfuscated C Code Contest (IOCCC) 2025 Winners
86 points by matt_d 3 hours ago | 10 comments
haunter 2 hours ago
The GameBoy emulator's code also looks like the GameBoy. Slow clap this is insane, definitely my favorite entry.
replyhttps://github.com/ioccc-src/winner/blob/master/2025/ncw1/pr...
The author, Nick Craig-Wood, is the creator of rclone!
yayitswei 31 minutes ago
In case anyone was wondering, the IOCCC specifically permits LLM use in their guidelines.
reply"The IOCCC has a rich history of remarkable winning entries created by authors who skillfully employed various techniques (often their own tools) to develop their code."
larodi 2 hours ago
Tis a pity to not have LLMs compete, given level of obfuscation they be capable of.
replylifthrasiir 2 hours ago
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.
replyAlotOfReading 48 minutes ago
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.
reply
[0] https://github.com/ioccc-src/winner/blob/master/2025/cable/p...
[1] https://github.com/ioccc-src/winner/blob/master/2025/cable/R...