CHEST is an experimental program solving orthodox chess problems (like "white to move and mate in 5 moves"). It is written in ANSI C, and developed under UNIX. There is no user interface: CHEST just reads an input file and produces plain text on standard output. It is not hard to come up with a program that does the same job as CHEST, but it will be rather slow for non-trivial jobs. CHEST tries hard to be fast but still 100% correct.