# Advanced Topics

Once you have become familiar with NixOS, you can explore advanced topics and dive deeper into the Nix ecosystem. Here are some resources and community projects that can help you expand your knowledge:

## Documentation

- [Nix Reference Manual](https://nixos.org/manual/nix/stable/package-management/profiles.html): A comprehensive guide to the Nix package manager, covering its design and usage from the command line.
- [nixpkgs Manual](https://nixos.org/manual/nixpkgs/unstable/): The manual for nixpkgs, which introduces its parameters, explains how to use, modify, and package Nix packages.
- [NixOS Manual](https://nixos.org/manual/nixos/unstable/): A user manual for NixOS, providing configuration instructions for system-level components such as Wayland/X11 and GPU.
- [nix-pills](https://nixos.org/guides/nix-pills): "Nix Pills" is a series of guides that provide an in-depth explanation of building software packages with Nix. It offers clear and understandable explanations.
- [nixos-in-production](https://github.com/Gabriella439/nixos-in-production): This is a work-in-progress book hosted on LeanPub about introducing and maintaining NixOS in a production environment.

## Advanced Techniques and Community Projects

Once you are comfortable with Flakes, you can explore more advanced techniques and community projects. Here are some popular ones to try out:

- [flake-parts](https://github.com/hercules-ci/flake-parts): Simplifies the writing and maintenance of configurations using the Module module system.
- [flake-utils-plus](https://github.com/gytis-ivaskevicius/flake-utils-plus): A third-party package that enhances Flake configuration and provides additional powerful features.
- [digga](https://github.com/divnix/digga): A comprehensive Flake template that combines functionality from various useful Nix toolkits. Note that it has a complex structure and may require some experience to navigate.

There are many other valuable community projects worth exploring. Here are a few examples:

- [nixpak](https://github.com/nixpak/nixpak): A tool to sandbox all sorts of Nix-packaged applications, including graphical ones.
- [nix-output-monitor](https://github.com/maralorn/nix-output-monitor): Beautifully displays the build progress of Nix packages, with additional information such as build time and build log.
- [agenix](https://github.com/ryantm/agenix): A tool for secrets management.
- [colmena](https://github.com/zhaofengli/colmena): Tools for NixOS deployment.
- [nixos-generators](https://github.com/nix-community/nixos-generators): A tool to generate ISO/qcow2/... from NixOS configurations.
- [lanzaboote](https://github.com/nix-community/lanzaboote): Enables secure boot for NixOS.
- [impermanence](https://github.com/nix-community/impermanence): Helps make NixOS stateless and improves system reproducibility.

These projects offer additional functionality and tools that can enhance your NixOS experience.

For more information, see the [awesome-nix](https://github.com/nix-community/).