Cargo Features

[dependencies]
staging-xcm = { version = "14.2.0", default-features = false, features = ["std", "wasm-api", "json-schema"] }
default = std

The std feature is set by default whenever staging-xcm is added without default-features = false somewhere in the dependency tree.

std default

Enables std of bounded-collections, parity-scale-codec, environmental, log, scale-info, serde, sp-runtime, and sp-weights

serde:

Provide impls for common standard library types like Vec<T> and HashMap<K, V>.
Requires a dependency on the Rust standard library.

wasm-api
json-schema

Enables schemars, json-schema of bounded-collections, json-schema of sp-weights

staging-xcm has 4 features without comments.