Nix ecosystem

The Core Nix Ecosystem is a collection of technologies designed to reproducibly build and declaratively configure and manage packages and systems as well as their dependencies. It achieves this by translating the functional paradigm from the program to the system domain by utilizing a dynamic, functional and lazy DSL called the Nix Language for specifying reproducible builds.

In addition there are many other applications (Extended Nix Ecosystem) developed by the Nix community, utilizing and supporting these core technologies.

Official ecosystem

Core Components of the Nix Ecosystem

Component	Manual	Description	Use	License
NixOS	NixOS Manual	A Linux distribution with all components built by Nix, and thus supporting reproducible and declarative system-wide configuration management as well as atomic upgrades and rollbacks.	Declaratively configure desktops, servers & clusters	MIT
Nixpkgs	Nixpkgs Manual	The largest community maintained Nix package and NixOS module repository; standard releases of NixOS are hosted here.	Share Nix packages & NixOS modules	MIT
Hydra	Hydra Manual	A Nix based continuous build system.	CI build farms	GPL-3.0
Nix	Nix Manual	A package manager that parses Nix expressions specifying reproducible build, putting the result in a store address with a hash of the dependency tree, sidestepping dependency hell and supporting multiversion installs and rollbacks.	Reproducible builds & package management in Linux & Darwin	LGPL-2.1

The NixOS core ecosystem stack

NixOS A Linux distribution and configuration system built using Nixpkgs
Nixpkgs A large, community-maintained repository of packages	Hydra A continuous build system built on Nix
Nix A pure and functional build system

Usage of NixOS

Users install the NixOS distribution on their computers just as any other Linux distribution. They read about packages to install and configuration options in Nixpgs via https://search.nixos.org and this wiki. They use the Nix language to declaratively describe in a text file what software packages should be installed and how the system should be configured. They run 2 command line programs in a terminal to transform the system into the described system. They use the system as any other Linux system.

Development of NixOS

Developers of NixOS mainly work on Nixpkgs to describe in text files in Nix language how software packages should be build. After peer review these changes are integrated in Nixpkgs. Some of these packages are pre built on Hydra to reduce the update time for NixOS users.