Jane Street Blog - Results from the ASIC puzzle
In August, we published a puzzle that handed you the final GDS layout of a small chip and asked you to work out what it did. We supplied the physical layout, but not a netlist or internal signal names, and it was up to you to reverse-engineer the internals. This post reveals what the chip does and explores the different ways you solved it, with shout-outs to some of our favorite submissions. We received about 400 submissions from more than 30 countries, the bulk from the US, India, the UK and Australia. Entrants included high school students, researchers, working engineers and retirees. Most solvers used KLayout, Yosys and Z3 alongside custom tools (many AI-written) implemented in Python, Rust, C++, OCaml, Haskell and even Odin. As many of you discovered, the chip is a hardware checker for an 11x11 Star Battle puzzle, also known as “Two Not Touch”. The goal is to place exactly two stars in each row, column, and colored region. No two stars can touch, even diagonally! The chip accepts 1