Cargo Features

async-fifo has no features set by default.

[dependencies]
async-fifo = { version = "0.6.3", features = ["blocking", "async-read"] }
blocking
async-read = futures-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.

futures-io async-read?