Cargo Features

[dependencies]
sameold = { version = "0.4.0", default-features = false, features = ["chrono"] }
default = chrono

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

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.

chrono default