io-trait is used at run time in 6 crates. It is a direct run-time dependency in 5 crates.

Depender (with downloads and own rev deps) io-trait version
380 nanvm ^0.11.0
220 2 io-impl ^0.11.0
220 2 io-test ^0.11.0
1 blockset-lib ^0.11.0
2 nanvm-lib ^0.11.0