There are several native Common Lisp implementations, as well as FFI bindings:
- chipz - Chipz is a decompression library for decompressing DEFLATE (RFC 1951) data such as ZLIB (RFC 1950), GZIP (RFC 1952), as well as bzip2
- cl-z - cl-z is a set of CFFI bindings to the zlib compression library
- hu.dwim.zlib - hu.dwim.zlib is a set of CFFI bindings to the zlib compression library
- Salza2 - Salza2 is a native Common Lisp compression library for creating data in the DEFLATE, ZLIB, or GZIP compression formats
To make it more annoying, there are at least two Common Lisp libraries also named "zlib":
- Franz zlib (native CL)
- Matthieu Villeneuve's zlib (also native CL)
In addition, CLisp has a module also called "zlib". It is part of the default "full" module linking set.