TL;DR
The winners of the 2025 IOCCC have been announced, featuring notable entries like a Subleq computer and a GameBoy emulator. The contest saw high-quality submissions despite a four-year hiatus. Details of the winning entries and their significance are outlined below.
The winners of the 2025 International Obfuscated C Code Contest (IOCCC) have been officially announced, with a diverse set of entries that push the boundaries of code obfuscation and creativity. The announcement followed a comprehensive judging process, and the winning entries are now available for review, marking a significant milestone for the coding and hacking communities.
The 2025 IOCCC saw a record number of submissions, with many authors building on past ideas and refining their entries after a four-year hiatus caused by the COVID-19 pandemic. The judging panel selected winners based on originality, complexity, and ingenuity, with notable entries including a Subleq computer implementation, a black hole punchcard Fortran program, and a GameBoy emulator.
Among the winners was a new author from Taiwan, jingp49, marking the first time a winner from that location has been recognized. The contest also saw repeat winners such as Yusuke Endoh, Nick Craig-Wood, and Don Yang, each securing multiple awards across different categories. The full list of winners and their projects is available on the official IOCCC website, along with links to the source code and detailed remarks from the authors.
Why It Matters
This announcement matters because it highlights the ongoing relevance and creativity within the programming community, especially in the niche of code obfuscation. The high quality and diversity of entries demonstrate continued innovation and serve as educational resources for programmers interested in low-level coding, hacking, and code golf. Additionally, the contest’s international participation underscores its global influence and the universal appeal of challenging programming puzzles.
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Background
The IOCCC has been held annually since 1984, serving as a platform for programmers to showcase their skills in writing intentionally obscure and complex C code. The 2025 contest was the second after a four-year break caused by the pandemic, which also saw an increase in the quality of submissions as authors refined their techniques. Past winners have often used the contest to demonstrate technical prowess and to push the limits of what can be achieved with C programming.
This year’s contest also introduced new rules and guidelines, reflecting an effort to streamline judging and encourage innovative approaches. The judging process involved detailed review of source code, with winners selected based on originality, technical difficulty, and entertainment value. The announcement was made via the Our Favorite Universe YouTube channel, with segments dedicated to each winning entry.
“The 2025 entries demonstrated exceptional creativity and technical skill, reaffirming the contest’s role as a hub for innovative obfuscated coding.”
— IOCCC Judge Panel
“Winning multiple awards this year shows how persistent effort and creative thinking can push the boundaries of obfuscated code.”
— Yusuke Endoh
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What Remains Unclear
While the winners have been announced and their source code published, details about the judging criteria for each entry and the full list of finalists remain partially undisclosed. The judging process is ongoing for some categories, and the possibility of later honorable mentions or community submissions is still open.
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What’s Next
The IOCCC organizers plan to open submissions for the 30th contest towards the end of 2026, with a deadline expected in Q1 2027. They also intend to document the process more thoroughly and encourage community participation in fun challenges related to the winning entries. Additionally, they will review community feedback and consider updates to contest rules for future iterations.
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Key Questions
What are some notable winning entries from the 2025 IOCCC?
Notable winners include a Subleq computer implementation, a black hole punchcard Fortran program, a GameBoy emulator, and a Dr. WHO sequence generator, among others.
How can I view the winning entries and source code?
All winning entries and their source code are available on the official IOCCC website, with links to detailed remarks and YouTube segments of the award presentation.
When will the next IOCCC contest be held?
The next contest, IOCCC30, is planned to open towards the end of 2026, with submissions closing in early 2027.
How does the judging process work?
The judging involves detailed review of source code for originality, complexity, and ingenuity, with winners selected by a panel of experts. The process is documented and transparent, with community input encouraged for fun challenges.
Source: Hacker News
