Snowboard Kids 2 is 100% Decompiled | Chris' BlogChris' BlogSnowboard Kids 2 is 100% Decompiled17 May, 2026I’m very pleased to announce that Snowboard Kids 2 is 100% decompiled!All of the game’s functions have now been implemented in C and compile to assembly that matches the original game. There’s still some occasional __asm__ hackery,1 and plenty of code needs better names and documentation, but every function now has a matching C implementation.That matters because a matching decompilation turns the game from a pile of MIPS assembly into a codebase we can read, build, study, and modify. It should help with recompilation, asset extraction, modding, and generally understanding the mechanics of the N64’s greatest game.Snowboard Kids 2 decompilation report from decomp.dev. Boxes represent different files.The journeyThis project has been a little under two years in the making, with the first commit landing in September 2024.The circumstances surrounding the final matches were not quite what I expected when I started. I’m currently sitting in hospital with my newborn daughter. She’s doing fine, but needs some help eating. Decompilation has been a useful distraction and an enjoyable way to fill the quiet hours.The path to decompiling any game, let alone a Nintendo 64 game, is not especially well documented. This project would not have been possible without the N64 decompilation Discord community, whose members have been incredibly generous with their time. I would particularly like to thank Bl00D4NGEL, inspectredc, SlaveOfIDO, and queueRAM for their significant contributions to the project, especially across the final ten functions.Leaderboard shared on discord for tracking work on the remaining Snowboard Kids 2 functions.The community was more important than any model: people answered my dumb questions, explained tooling, and decompiled functions themselves. With that said, coding agents also greatly accelerated the decompilation effort, particularly Claude, GLM, and Codex. I don’t want to turn this into another AI blog post2, but I do have a couple of observations:Based on my experience with the final ten functions, which were among the most difficult, the most effective model appeared to be Codex 5.5 xhigh. Historically Claude was more effective, and I expect this to keep changing, perhaps even by the time you read this.Frontier models are now very effective at decompilation, but this comes at a cost. GLM has probably been the best value for money for this specific kind of work. If you want to try coding agents on your own decompilation project but are put off by high subscription fees, that is where I would start.What next?Reaching 100% decompilation was not technically blocking the recompilation effort, but it was more interesting to me personally. With the decompilation finished, my next goal is to release a high-quality recompilation of Snowboard Kids 2.That’s already in a pretty good state thanks to help from sonicdcer and DarioSamo, but there are still bugs to squash before I’m comfortable releasing it.Screenshot from Snowboard Kids 2: Recompiled. Note the use of widescreen and expanded draw distance. This can lead to some visual quirks.There’s also plenty of work left to do in the decompilation project itself. A 100% match doesn’t mean the source is perfectly understood. Many functions still have generated names, many structures need to be cleaned up, and graphics/audio assets are still mostly treated as binary blobs. The project is now in a much better place for that work, but the work still needs doing.Finally, I’m interested in starting a Snowboard Kids 1 decompilation. I think it would be very cool to have a ‘Super Snowboard Kids’3 that combines both games and allows you to play all the original tracks on the second game’s more modern engine. I have no idea how feasible that ultimately is, but it’s a fun thing to think about.If you’ve made it this far, you probably have an interest in decompilation and Snowboard Kids 2. Take a look at the Snowboard Kids 2 decompilation project. The README includes a list of good first tasks.You can also follow me on Bluesky for more Snowboard Kids 2 updates.The project uses some targeted __asm__ instructions to coerce variables into particular registers, ensure writes happen at the appropriate time, etc. Generally, these could be removed and the game would function in exactly the same way (albeit no longer byte-for-byte matching). Still, ideally this wouldn’t be needed at all, and the long-term goal is to remove them. ↩︎I have three of those already if you’re interested. ↩︎Trivia: this was actually the title of Snowboard Kids 2 in Japan! ↩︎<< Previous Post|Next Post >>

The process of decompiling Snowboard Kids 2 has resulted in a complete implementation of all game functions in C, which compile to assembly that precisely matches the original game. Although some instances of __asm__ hackery remain, the successful matching of the original code allows the resulting codebase to be read, studied, and modified, opening avenues for recompilation, asset extraction, modding, and a deeper understanding of the game's mechanics. This extensive effort spanned nearly two years, and the project benefited significantly from collaboration within the N64 decompilation Discord community, where members provided essential assistance across the final ten difficult functions.

The project’s execution was also accelerated by the use of coding agents such as Claude, GLM, and Codex. The author observed that among the most challenging functions, the Codex 5.5 xhigh model proved to be the most effective tool, while GLM offered strong value for this type of work. The journey of the decompilation was characterized by community engagement, where members provided explanations and solutions, demonstrating that the community input was more critical than any single model.

Beyond the technical achievement of full decompilation, the project has further goals. The immediate next step is to release a high-quality recompilation of Snowboard Kids 2, which involves addressing remaining bugs before release. Furthermore, even at 100% decompilation, the source code still requires refinement; many functions have generated names that need cleaning up, data structures require reorganization, and graphics and audio assets remain largely in binary form. The project still necessitates work to fully understand and structure these elements. The author also expressed interest in initiating a decompilation of Snowboard Kids 1 with the aim of creating a composite game, tentatively envisioned as a 'Super Snowboard Kids,' merging the content of both titles onto the engine of the second game.

Technically, the decompilation process involved the use of targeted __asm__ instructions to manage variable placement and execution timing, which the author notes are ideal candidates for removal to achieve byte-for-byte matching without the hackery. In summary, the effort transformed the game from raw assembly into a readable and modifiable codebase, while simultaneously establishing a foundation for future development and exploring related game assets through advanced decompilation techniques, including the consideration of integrating elements from Snowboard Kids 1.