Cargo Features
openssl-async has no features set by default.
[dependencies]
openssl-async = { version = "0.3.0-alpha.5", features = ["tokio"] }- tokio = tokio-io
Features from optional dependencies
In crates that don't use the dep: syntax, optional dependencies automatically become Cargo features. These features may have been created by mistake, and this functionality may be removed in the future.