I did a Lua implementation of a depacker for the zlib/deflate algorithm. It’s quite efficient for Lua code, even though it obviously won’t compete with a compiled implementation. It can be useful in Lua environments where no access for native C libraries are possible, like the PICO-8 platform.

Performance tests show that typical run times to depack lua-5.3.3.tar.gz on my 2013 i5 laptop are 0.87s with Lua 5.3, and 0.28s with LuaJIT 2.0.4.

The source code and documentation are available on Github, and is made available under the WTFPL license.