Cargo Features

TextDb has no features set by default.

[dependencies]
textdb = { version = "0.1.0", features = ["mmap"] }
mmap = memmap2

Affects maps::UnsafeMemoryMap

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.

memmap2 mmap?