Doors is an attempt to bring essential features of MS Windows (such as basic Windows API, COM and OLE) into Common Lisp.

It is a high-level FFI binding with a lisper-friendly interface. It can be obtained from Github here:

It uses Virgil as a back-end. It also depends on trivial-features, alexandria, trivial-garbage, closer-mop, and bordeaux-threads.

Doors is also the name of an "embryonic" attempt at a window manager for McCLIM: