Jane Street published results for its ASIC reverse-engineering puzzle. The chip checks solutions to an 11x11 Star Battle puzzle. It verifies two stars per row, column, and region with no adjacent stars. The design uses SKY130 open-source cells and LibreLane tools. Solvers extracted netlists, simulated logic, and used SAT solvers to crack it. Over 400 submissions arrived from more than 30 countries. Many used AI tools to automate parts of the process. The chip outputs success or Easter egg messages like 'TRY AGAIN' or 'TWO NOT TOUCH'. Hidden details included a Jane Street logo in metal-2 and Morse code. A floating wire bug in the output path was left as an Easter egg.
What changed
The puzzle chip's function and internal logic were unknown; solvers had to reverse-engineer the GDS layout without a netlist or signal names.
What it unlocks
Understanding how the ASIC enforces Star Battle puzzle rules and decodes its obfuscated output.
- 400 submissions
- 30+ countries
- 11x11 Star Battle grid
- 121 input cycles
What you need to act on it
- access to GDS layout files
- tools like KLayout, Yosys, or custom scripts
- knowledge of hardware design or reverse-engineering
Sources