Cargo Features

columnar_derive has no features set by default.

[dependencies]
columnar_derive = { version = "0.0.1", features = ["verbose"] }
verbose = rustfmt

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.

rustfmt verbose?

Enables rustfmt ^0.9