Decompiling one game took years. AI made it so easy the hub quit

TL;DR: Matching decompilation, rebuilding an old game's source code byte for byte, used to take years per game. Today decomp.dev, the hub that tracked those projects, switched off new projects because AI made the work fast, cheap and impossible to moderate. AI didn't kill the craft. It killed the scoreboard.

A hobby that took years now takes a subscription

On Oct 15, the admin of decomp.dev, who goes by Encounter, posted "Sunsetting decomp.dev." The site was born in 2024 to track fan projects that rebuild classic games' source code (the kind of work that once got Super Mario 64 running natively on PC) and to give the people doing it a home.

Their own words on how hard that used to be: "brutally difficult, time consuming," "on the scale of years for any moderately-sized game."

Plain-English note: "matching" decompilation means you write C code that, when built with the game's original compiler, produces the exact same machine code as the cartridge. Not close. Identical. That is why it took years, and why a checker can grade it automatically.

Which models broke it, per the admin

Encounter is weirdly specific, which I love. Starting with Opus 4.6 and GPT-5.4 in early 2026, the models seemed to already know the community's tools without being told. But results needed lots of human cleanup, plus fixes for "cheating": code that technically compiles to the same bytes but no human dev would ever have written. And it cost too much.

Then GPT-6-Astra landed. Per the post, it follows complex directions, cross-references debug symbols, writes natural code, and is an "exceptionally good" permuter: it writes little scripts that try many versions of a function until one matches. And it stays on task for hours. Faster, better and cheaper at the same time.

The same day, 404 Media's Jason Koebler covered the shutdown and pointed at decomp.wtf, a new free tool that lets you "point the AI agent you already use at a game you own," Claude Code or Codex included, and checks every function byte for byte.

The flood: hostile forks and half-baked ports

The admin lists what broke the community, and none of it is "AI is bad." It's behavior:

Hostile forks. People copy a human-led project and "finish" it with AI, putting "little to no effort" into the original.

Port races. Humans do years of decomp work, then someone with "an AI subscription" ships a "half-baked, barely-functional port" first and takes the attention.

Decomp now means PC port. Encounter calls out "Sloptubers" and r/decomps for using "decomp" to mean "PC port," when the hobby was mostly about research: understanding how these games actually work.

The news is traveling. Pirat_Nation's post on it had 846 likes and 45 replies at 4:40 PM ET, about 1.5 hours in.

The progress bar was the real casualty

This is the line that hit me hardest. decomp.dev was built to gamify the work: a progress bar per game, where "every fraction of a percent took real human effort."

Once a model can push that bar for the price of tokens, the bar stops meaning effort. It just means spend. And a public leaderboard that rewards spend is basically an ad for whoever burns the most compute.

So Encounter didn't ban AI. They say AI "can help tremendously when used correctly," and that as a "sole hobbyist" they can't police what a "good" decompilation is across hundreds of projects. The index and new submissions are off. Old project pages and history stay up.

My bet: "human-led" becomes a label

Hot take, not a fact: I think every craft scene with a public scoreboard is about to have this exact week. Speedrun boards, bug bounties, open-source contribution graphs, Kaggle-style leaderboards. Anywhere the metric is "output that passes a check," AI makes output cheap, and the metric goes hollow.

My guess is the next decomp hub ships with provenance tags: human-led, AI-assisted, AI-finished. Kind of like "human-made" is becoming a label in art. Nobody knows yet if people will actually filter by it, but lowkey I think the projects that keep their communities will be the ones that make the human part visible instead of hiding the AI part.

The other quiet lesson: "it compiles to the same bytes" was never the same as "it's good code." Encounter's word for that gap was cheating. Same gap shows up everywhere AI writes code that passes the test.

The numbers so far

• decomp.dev founded: 2024 (Encounter's post)
• Time per moderately-sized game, before: years (Encounter's post)
• Models named: Opus 4.6, GPT-5.4 (early 2026), then GPT-6-Astra
• Projects on the site: hundreds (admin's word, no exact count given)
• New projects and main index: off as of Oct 15 2026; existing pages stay
• Pirat_Nation post: 846 likes, 45 replies at 4:40 PM ET Oct 15

Your app passes the demo. Does it pass a real check?

If you ship apps with Lovable, Bolt, Cursor, Replit or Supabase, you're living a mini version of this: the AI got it to "works on my screen" fast, and nobody checked what a stranger can do with it. The $49 Launch Check is a plain-English security and config check for apps built with Lovable, Bolt or Supabase, before you launch. One checkout, no call: shop.tensorust.com/buy/launch-check

What happens next

decomp.dev keeps serving existing project pages. Some folks in the replies are already pointing at replacement trackers; I haven't checked those, so no names here. Watch whether Nintendo-era decomp projects start writing AI policies into their READMEs. My bet is yes, within weeks.

Question for you: if a fan project is 100% byte-matching but 90% AI-written, is it still a decomp you'd celebrate? Or does the human part matter?

Sources: decomp.dev "Sunsetting decomp.dev" (Encounter, Oct 15 2026); 404 Media, Jason Koebler, "Video Game Reverse Engineering Community Shuts Down Because AI Has Made It Too Easy," Oct 15 2026 12:31 PM; decomp.wtf homepage; Pirat_Nation on X, 3:02 PM ET Oct 15 2026.