Cargo Features

[dependencies]
either = { version = "1.10.0", default-features = false, features = ["use_std", "serde"] }
default = use_std

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

use_std default

Features from optional dependencies

serde implicit feature

Enables serde

serde:

A generic serialization/deserialization framework

Affects either::serde_untagged, either::serde_untagged_optional