Cargo Features

[dependencies]
jsonwebtokens = { version = "1.2.0", default-features = false, features = ["matching"] }
default = matching

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

matching default = regex

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.

regex matching