libz-rs-sys is used at run time in 3 crates (of which 1 optionally). It is a direct run-time dependency in 2 crates.

Depender (with downloads and own rev deps) libz-rs-sys version
7.8M 2049 flate2 optional ^0.3.0
150 libz-rs-sys-cdylib ^0.3.1