Nix Shell

The nannou repo offers a Nix shell as a way of providing a reproducible environment across both macOS and Linux. This simplifies the nannou repo CI a little while making it easier to experiment with nannou using a known working environment.

Installing Nix

The Determinate Systems installer is one of the easiest ways to get started with Nix.

Nannou’s Nix Files

• default.nix - A derivation that describes how to build the nannou Rust package, including all of its examples and with all of the necessary environment variables. This is what is built by default when running nix build. When
• shell.nix - A derivation that describes a development shell providing all of the necessary system dependencies and environment variables for working on nannou and its examples.
• flake.nix - A Nix manifest standard declaring the nannou package and devShell.

Adding a nannou Dependency

When adding a new package (e.g. system dependency):

1. Find the package in nixpkgs (nix search nixpkgs <name> is handy)
2. Add the package to the default.nix input attribute set.
3. Add the package to buildInputs if its a runtime dependency, or nativeBuildInputs if its a build-time dependency.

Adding a Development Shell Dependency

To add handy development dependencies (e.g. rustfmt, rust-analyser), do the same but add them to shell.nix instead.

Adding Environment Variables

Add these to the env attributes within either default.nix or shell.nix.

Build Everything

Build all binaries, examples and dylibs within the nannou workspace with nix build. When finished, look in the result symlink directory to find all of the built binaries.

Enter a nannou devShell

To enter a development shell with all of the tools and env vars necessary for nannou dev, use nix develop.

To quickly enter a nannou dev shell to build a downstream nannou project, you can use: nix develop github:nannou-org/nannou.