cbor4ii is used at run time in 44 crates (of which 3 optionally, 2 directly). It's used only as a dev dependency in 1 crate.

Depender (with downloads and own rev deps) cbor4ii version
35K 1 test-fuzz-runtime optional ^0.2.13
15K 7 serde_ipld_dagcbor ^0.2.13