Cargo Features

[dependencies]
sparsey = { version = "0.13.1", default-features = false, features = ["std", "parallel"] }
default = std

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

std default parallel?

Enables std of rustc-hash

parallel = std

Enables rayon

Sparsey has 3 features without comments.