Cargo Features

failure = { version = "0.1.8", default-features = false, features = ["std", "derive"] }
default = derive, std

These default features are set whenever failure is added without default-features = false somewhere in the dependency tree.

std default = backtrace
derive default = failure_derive

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.

backtrace std
failure_derive derive