// HACKER NEWS — CYBERSECURITY
Decompiling a Nintendo 64 Game in 84 Days
I’m very pleased to announce that the original Snowboard Kids is now 100% decompiled! This means that all functions1 have matching C implementations that, when compiled, produce identical machine code to the original game.
This was obviously not a one-person effort. I am particularly grateful to inspectredc, Bl00D4NGEL, and queueRAM for their significant contributions to the project. No amount of AI would have been able to replace them.2 I would also like to thank iFuzzle, JamesBLewis, and douglasjv for lending their tokens to the cause.
My hope is that a full decompilation will prove useful to the Snowboard Kids community. Speedrunners in particular have long focused on the first game. Working source code can help shed light on externally observed phenomena such as CPU pathing and the exact factors contributing to player speed. A full understanding of the source code will also be useful for static recompilation and more ambitious modding efforts in the future.
The speed at which the project was finished is also noteworthy. Snowboard Kids took only 84 days to decompile compared with 596 days for Snowboard Kids 2, roughly one-seventh of the elapsed time.3
Weekly progress of the Snowboard Kids decompilation.
What explains this difference? Well, it’s 2026, so the answer is at least partially AI. But it would be a gross oversimplification to attribute the difference entirely to LLMs.
To state the obvious, I was not starting from scratch. By this point I had already spent nearly two years on a similar project and was vastly faster than when I began. This advantage is difficult to quantify and was somewhat offset by new challenges such as working with a different compiler.
Overall, roughly 4.8% of matching commits involved expert intervention.4 I have already credited these amazing people once, but it’s worth reiterating. This project would not have been possible without significant help from the decompilation community, particularly inspectredc, queueRAM, and Bl00D4NGEL <3.
The difficulty generally didn’t come from trying to understand what a function did5 but rather how that logic was expressed in C and how the resulting code was compiled. Snowboard Kids was compiled with IDO 5.3 rather than the GCC 2.7.2 compiler used by Snowboard Kids 2.
Most programmers will be familiar with GCC. It is a widely used open-source compiler still in active development today. IDO, on the other hand, was a proprietary compiler developed by SGI, whose own story is closely entwined with that of the Nintendo 64.6 Its source was not available, and its original development environment was tied to obsolete SGI hardware and software. To use and properly understand it today, the decompilation community has had to reverse-engineer and decompile parts of the compiler toolchain as well as statically recompile the IDO 5.3 and 7.1 suites to run on modern hardware. That closed history makes IDO harder to reason about than an open compiler such as GCC.