RC4 is used at run time in 11 crates (of which 2 optionally). It is a direct run-time dependency in 6 crates.

Depender (with downloads and own rev deps) RC4 version
750 3 cart_container ^0.1
150 1 malwaredb-server ^0.1.0
130 spectrex ^0.1.0
3 himmelblau_kerberos_crypto ^0.1.0
pso2packetlib optional ^0.1.0
rawtx-rs optional ^0.1.0