Reverse engineering can reveal how software was made, as well as how it runs. Examining unused memory with C64 RE Tools uncovered source fragments, older code and traces of development tools in surviving releases of Datasoft’s 1984 C64 game Bruce Lee.

About 6 KB of the captured game image held material outside the active game: assembler text, an older symbol table, routines and sprites from earlier layouts, a demo recording and fragments of development tools.

Some clues connect directly to the finished Bruce Lee program. Graphics bytes in the source fragment match room tiles. Address shifts align old labels with later routines and frames. A music pointer skips an earlier section of the title tune. These are artifacts of the game’s development, uncovered using the toolkit.

The companion Bruce Lee research project follows each finding and separates byte-level observations from historical interpretations. The source format does not prove which development machine was used, and no complete original source tree was recovered.

Bruce Lee research project: https://hackaday.io/project/207112-bruce-lee-1984-development-archaeology

Bruce Lee development report: https://github.com/henols/c64_games/blob/main/bruce_lee/docs/development.md