Cargo Features

data_reader has no features set by default.

[dependencies]
data_reader = { version = "0.5.0", features = ["mmap"] }
mmap = memmap

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.

memmap mmap?

Enables memmap2 ^0.5.5