Template: Flake Parts Modules

The flake-parts-modules template demonstrates how to use Den aspects that propagate custom classes into third-party flake-parts perSystem modules.

For demo purposes, the example showcases:

• perSystem.packages: How to expose flake-parts packages.
• numtide/devshell: A default devshell extensible by any aspect.
• mightyiam/files: Generates README from nix code.
• nix-community/nix-unit: Write tests directly on aspects.

Initialize

mkdir example && cd example
nix flake init -t github:vic/den#flake-parts-modules
nix flake update den
nix flake show
nix flake check -L

Project Structure

flake.nix
modules/
  perSystem-forward.nix # Custom den.ctx and perSystem forwarding class.
  custom-classes.nix # Registers several classes for each third-party
  den.nix   # Example of aspects using those classes

Key points:

• New perSystem classes are registered via a context transition, from any module.

Next Steps

• Read flake.parts Documentation for more perSystem modules.