Cargo Features

[dependencies]
wavup = { version = "0.1.4", default-features = false, features = ["logging"] }
default = logging

The logging feature is set by default whenever wavup is added without default-features = false somewhere in the dependency tree.

logging default = log

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.

log logging