Cargo Features

CountWrite has no features set by default.

[dependencies]
count-write = { version = "0.1.0", features = ["futures", "tokio"] }
futures = futures-io-preview
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.

futures-io-preview futures?
tokio-io tokio?