Priyome is a complete chess computer in single plain C source code file. It was written to be easily ported to other even more primitive languages. E.g. it uses only integers and does not require structures. The AI is implemented using standard chess computer techniques such as alpha beta pruning search with iterative deepening, quiescence optimization (only checking for captures beyond a specific depth) and a memory efficient solution for transposition table lookup.
A B C D E F G H +-----------------+ 8 | r n b q k b n r | 8 7 | p p p p p p p p | 7 6 | . . . . | 6 5 | . . . . | 5 4 | . . . . | 4 3 | . . . . | 3 2 | P P P P P P P P | 2 1 | R N B Q K B N R | 1 +-----------------+ A B C D E F G H White's turn. >
It was not designed to be the best chess computer in the world, but still put up a strong fight against any human player. The primary objective is a clean and portable source code.
License is “New Simplified BSD License” (basically do what you want with it, but give credit where credit is due).