depot/third_party/nixpkgs/doc/languages-frameworks/node.section.md

Node.js

The pkgs/development/node-packages folder contains a generated collection of NPM packages that can be installed with the Nix package manager.

As a rule of thumb, the package set should only provide end user software packages, such as command-line utilities. Libraries should only be added to the package set if there is a non-NPM package that requires it.

When it is desired to use NPM libraries in a development project, use the node2nix generator directly on the package.json configuration file of the project.

The package set provides support for the official stable Node.js versions. The latest stable LTS release in nodePackages, as well as the latest stable Current release in nodePackages_latest.

If your package uses native addons, you need to examine what kind of native build system it uses. Here are some examples:

• node-gyp
• node-gyp-builder
• node-pre-gyp

After you have identified the correct system, you need to override your package expression while adding in build system as a build input. For example, dat requires node-gyp-build, so we override its expression in default.nix:

dat = nodePackages.dat.override (oldAttrs: {
  buildInputs = oldAttrs.buildInputs ++ [ nodePackages.node-gyp-build ];
});

To add a package from NPM to nixpkgs:

1. Modify pkgs/development/node-packages/node-packages.json to add, update or remove package entries to have it included in nodePackages and nodePackages_latest.
2. Run the script: (cd pkgs/development/node-packages && ./generate.sh).
3. Build your new package to test your changes: cd /path/to/nixpkgs && nix-build -A nodePackages.<new-or-updated-package>. To build against the latest stable Current Node.js version (e.g. 14.x): nix-build -A nodePackages_latest.<new-or-updated-package>
4. Add and commit all modified and generated files.

For more information about the generation process, consult the README.md file of the node2nix tool.