Cargo Features

flume = { version = "0.11.0", default-features = false, features = ["spin", "select", "async", "eventual-fairness"] }

Use a spinlock internally (may be faster on some platforms)

default = async, eventual-fairness, select

These default features are set whenever flume is added without default-features = false somewhere in the dependency tree.

select default eventual-fairness

Affects flume::select

async default = futures-core, futures-sink

Affects flume::r#async

eventual-fairness default = nanorand, select

Features from optional dependencies

In crates that don't use the dep: syntax, optional dependencies automatically become Cargo features.

futures-sink async
futures-core async
nanorand eventual-fairness