# Nix

> A package manager and programming language used to define reproducible development environments.

*Nix* is both a package manager and a functional programming language used by Panfactum to
codify local developer environments and tooling.

Panfactum uses Nix to:

- **Define the DevShell**: All development tooling is declared in various `flake.nix` files and built reproducibly by Nix
- **Pin tool versions**: Specific versions of every tool are locked, ensuring all developers and CI systems use identical binaries
- **Isolate environments**: Nix installs packages in isolation without polluting system paths

Nix hosts **nixpkgs**, one of the largest software repositories in the world, making nearly any
tool available as a Nix package. Panfactum leverages [Nix flakes](https://nix.dev/concepts/flakes)
for reproducible, version-locked environment definitions that integrate with `direnv` for
seamless shell activation.

> **Note:** You do not need to learn the Nix language to use Panfactum. The `flake.nix` file
> follows a straightforward template, and adding custom tools requires only minimal edits.