<p><a href="https://wiki.nixos.org/wiki/Flakes">Nix flakes</a> are an
experimental feature of the <a
href="https://wiki.nixos.org/wiki/Nix_(package_manager)">Nix package-management
tool</a> designed to build projects in a more self-contained and reproducible
way. Despite the feature's experimental status, it has become increasingly
popular for open-source projects to publish <tt>flake.nix</tt> files that offer
predefined development environments and build automation even when those
repositories may not offer an upstream package or module for the <a
href="https://wiki.nixos.org/wiki/NixOS">NixOS Linux distribution</a>. Although
Nix flakes have a complicated history, and the path for stabilization is
uncertain, flakes can provide useful capabilities for projects that choose to
include them.</p>