Cargo Features

Coveralls has no features set by default.

[dependencies]
coveralls = { version = "0.1.5", features = ["std", "libgit"] }
std
libgit = git2

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.

git2 libgit?

Enables git2 ^0.18.3