SPMC is used at run time in 34 crates (of which 1 optionally). It is a direct run-time dependency in 18 crates. It's used only as a dev dependency in 10 crates.

Depender (with downloads and own rev deps) SPMC version
1.4K pathbuster ^0.3.0
400 6 jubako ^0.3.0
230 2 tokio-http2 ^0.2
130 aleo-wasm ^0.3.0
2 vomit-sync ^0.3.0
obnam ^0.3.0
hrekt ^0.3.0
mula ^0.3.0
build_pbf_glyphs ^0.3.0
1 vomit-m2sync ^0.3.0
ghopac ^0.2.2
gosh-remote ^0.3.0
aem-eye ^0.3.0
hostparser ^0.3.0
sotahyper ^0.2
bgapi ^0.2.2
cargo-cleansubdirs ^0.3
qrep ^0.2.2
11.4M 3586 hyper dev ^0.3
10K 2 hyper2 dev ^0.3
1.0K 7 hyper_wasi dev ^0.3
470 1 rhyper dev ^0.3
110 3 hyper_imp dev ^0.3
supply-chain-trust-example-crate-000081 dev ^0.3
1 rama-hyper dev ^0.3
anony dev ^0.3.0
burst-pool dev ^0.2.2
1 hyper-patch dev ^0.3