A Reverse-Engineering Tool Reached the Top of GitHub

Around October 9, 2026, REA (Reverse Engineer Anything) appeared on GitHub Trending. It is an MIT-licensed command-line tool and MCP server that lets AI coding agents inspect software without its source code: native binaries, JavaScript and Electron apps, .NET assemblies, Android packages, websites, firmware and WebAssembly. At the time of writing the repository shows more than 100,000 stars. Reactions split quickly. Some called it the end of paid software; others dismissed it as a wrapper around old tools. Both camps are partly right, and the useful part lies between them.

What It Actually Does

REA is an orchestrator, not a new decompiler. It connects an agent to reverse-engineering tools that have existed for years, such as Ghidra, IDA and Hopper for native code, plus tools for Android packages and JavaScript bundles. The agent decides what to inspect; REA runs the tools locally and returns findings with the evidence behind them. According to an independent review by GitTested, the project is roughly six months old and mostly maintained by one person, so its capabilities change quickly between releases.

What the First Independent Test Found

GitTested ran REA with Claude Code on four small stripped binaries and three Electron apps in October 2026. REA drove Ghidra reliably: 92 of 95 calls returned usable output, and decompiled code matched the source where checked. But the agent using only standard shell tools scored 74 of 75 on the native checklist, against 73 of 75 with REA, and both scored 57 of 60 on the Electron apps. Median token use rose about 2.5 times, from roughly 95,000 to 234,000 per session. When given a free choice, the agent called REA in only 3 of 18 sessions. Large or obfuscated programs were not tested, and that is where such a tool should matter most. The fair summary: it works, it is not magic, and on simple targets a capable agent barely needs it.

Why More Tools Like This Are Coming

The real change is that the cost of understanding software is collapsing. Reverse engineering was scarce because it was slow and tedious, not because the tools were secret; Ghidra has been free for years. AI agents supply the patience to read thousands of decompiled functions, form a theory and test it. That makes REA easy to copy and improve. Expect specialised tools for single targets such as game engines, mobile apps or industrial file formats, and tighter rebuild-and-verify loops. GitTested already rewrote five recovered functions in C and checked them against 7,092 inputs. The next step needs no decompiling at all: an agent observes screens, files and traffic, then writes a clean implementation that behaves the same way.

What Changes for Companies That Sell Software

Anything that runs on a customer's machine should now be treated as readable. Obfuscation and licence checks inside an app raise the cost of copying, but that is exactly the cost AI is driving down. Value moves to places a decompiler cannot reach: logic and data kept on the server, the customer history and integrations that a copied binary does not contain, and the support, updates and accountability that a clone does not come with. The most exposed products are small client-side tools with one clever feature and a premium price. Expect more software to become a thin client over an API.

What Changes for Businesses Running Old Software

For most small businesses this shift is good news, and it has nothing to do with copying anyone. Many run on systems nobody can fully explain any more: a database app built by a former employee, a spreadsheet full of macros, or a desktop tool whose vendor has disappeared. Until recently, documenting or replacing such a system often cost more than it was worth, because someone had to study it for weeks to recover every hidden rule. That analysis is the part AI now makes cheaper. Three kinds of work become realistic on a modest budget: documenting what an undocumented system actually does, migrating it to a modern web app while the old one runs alongside until results match, and integrating a tool that has no API through its files, exports or traffic.

Security and the Law

The same capability helps attackers: finding weaknesses in an app or a device's firmware gets cheaper for them too, and defenders will need the same tools to look first. The law is uneven. In the EU, Article 6 of the Software Directive allows decompilation without permission only where it is indispensable for interoperability, done by a lawful user, and limited to the necessary parts. Australia's section 47D of the Copyright Act allows reproducing a program to obtain the information needed to make an independent, interoperable program, within similar limits. Licence agreements can add further restrictions, and none of this permits copying a product or defeating its licensing. This is not legal advice: if the software is not yours, get permission before you open it up.

Practical Next Steps

If you run a business on software, list the systems that only one person understands. Those are your largest operational risk and are becoming the cheapest to fix. Make sure the data inside them can be exported and that you control it. If you build software, assume your client code will be read, keep your real advantage on the server, and point the same tools at your own product before someone else does. If you want to try a viral tool like REA, run it in a sandbox, pin the version you tested, and read what its setup changes. GitTested notes that it adds 139 tools to an agent and roughly doubles the agent's starting context.

The Bottom Line

REA will likely be overtaken by sharper tools within a year. What remains is the new baseline: compiled software is no longer a reliable way to keep logic private, and understanding an existing system is no longer the expensive part of changing it. When code stops being scarce, value moves to judgement and responsibility: deciding what is worth rebuilding, keeping it running and standing behind it. ZaidanLab's AI integration work applies that principle to connecting and modernising existing business systems.