Cargo Features

Polylabel has no features set by default.

[dependencies]
polylabel = { version = "3.2.0", features = ["headers", "ffi"] }
headers = cbindgen
ffi = libc

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.

libc ffi?
cbindgen build headers?