Cargo Features

jasmine-db has no features set by default.

[dependencies]
jasmine-db = { version = "0.1.1", features = ["shuttle", "mmap"] }
shuttle
mmap = libc

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.

libc mmap?