Cargo Features

[dependencies]
r1cs = { version = "0.4.7", default-features = false, features = ["std"] }
default = std

The std feature is set by default whenever r1cs is added without default-features = false somewhere in the dependency tree.

std default

Enables std of bimap ^0.4.0, use_std of itertools ^0.8.0, std of num ^0.2.0 and num-traits

R1CS has 2 features without comments.