A Tangram Puzzle Solver in Common Lisp

In this demo, we present a Common Lisp program capable of solving
arbitrary geometric tiling problems. Well-known examples of such
problems are Tangram puzzles. The program is implemented in Common
Lisp, using the Common Lisp Interface Manager (CLIM) for its GUI. It
consists of an editor and solver. We describe and demo the program and
comment on its implementation as well as employed techniques to make
the approach feasible.