Cargo Features

[dependencies]
circe = { version = "0.1.5", default-features = false, features = ["tls", "debug", "toml_support"] }
default = tls

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

tls default = native-tls
debug
toml_support = serde, serde_derive, toml

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.

native-tls tls
serde toml_support?
serde_derive toml_support?
toml toml_support?

Enables toml ^0.5