Developer reports AI agents rebuilt Call of Duty MW2 source code with 83% byte-for-byte match

Developer Maurice Heumann published a report on October 9 stating that his team used AI agents to decompile and reconstruct the C++ source code of the 2009 game 'Call of Duty: Modern Warfare 2' over three months. The final result included 99% of game functions in the reconstructed source, with 83% achieving byte-for-byte matching against the original binary.

The project initially used Claude and Codex subscriptions to run multiple agents, which could launch the game but contained numerous semantic errors. The team then introduced a 'byte-for-byte matching' verification mechanism, comparing reconstructed functions against the original EXE/PDB files. By prohibiting inline assembly and using CI hash checks to prevent agent cheating, they enabled low-cost models to complete high-precision tasks under strict feedback.

The results are currently kept for private use only, with no public code release, meaning the outcomes have not yet been independently reproduced or verified by the community.