Auburn's FastNoise library is amazing - it's fast, covers all the commonly used types of noise, and has been ported to many systems. This crate ports much of that functionality (more is being ported in each version) to Rust. It is part of the bracket-lib family of crates.
You may run examples with cargo run --example <name>. The examples use crossterm for easy terminal output.
simplex_fractal uses Fractal Simplex Noise to make a heightmap, and outputs it to your terminal.perlin_fractal uses Fractal Perlin Noise to make a heightmap, and outputs it to your terminal.white_noise outputs a randomized white noise sample to your terminal.value outputs "value noise" to your terminal. This is a bit like white noise but smoother.value_fractal outputs "fractal value noise" to your terminal.cellular provides a dump of cellular noise. Until the functions to look up the base noise layer from another noise generator are implemented, this is of limited utility.simplex_billow_quintic and simplex_rigid_hermite demonstrate some noise tweaking options.