Cargo Features

rss-watch = { version = "0.1.0", default-features = false, features = ["json"] }
default = json

The json feature is set by default whenever rss-watch is added without default-features = false somewhere in the dependency tree.

json default = serde_json

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.

serde_json json