It's used only as a dev dependency in 9 crates.

Depender (with downloads and own rev deps) Timebomb version
63K 76 zmq dev ^0.1.2
650 7 hoedown dev ^0.1.2
200 8 zmq2 dev ^0.1.2
sawtooth-zmq dev ^0.1.2
2 delay-queue dev ^0.1.2
follow dev ^0.1
2 zmq-pw dev ^0.1.2
tmq-zmq dev ^0.1.2
rustot dev ^0.1.2