syn_derive is used at run time in 223 crates (of which 31 optionally). It is a direct run-time dependency in 7 crates. It's used only as a dev dependency in 8 crates.

Depender (with downloads and own rev deps) syn_derive version
47K 19 rstml ^0.1.6
650 forward-traits ^0.1
200 1 odra-macros ^0.1.8
120 1 sumtype-macro ^0.1.8
1 chandeliers-syn ^0.1.7
rstml-control-flow ^0.1.6
220 1 html-node-macro optional ^0.1