Salza2
Salza2 is a native Common Lisp compression library for creating data in the DEFLATE, ZLIB, or GZIP compression formats. It does not yet support decompression. Take a look at chipz for a native Common Lisp library providing DEFLATE/ZLIB decompression.

It is a from-scratch reimplementation of Salza, which suffered from some design mistakes that made it slower and harder to maintain than it needed to be.

It is available under a BSD-style license. Full documentation is available on the Salza2 home page.