What is Nix?

Nix is a powerful, cross-platform package manager that offers a high ‘power-to-weight ratio’. It provides a range of features including reproducible development environments, system configuration, language-agnostic build-tool, continuous integration environment, deployment machine configuration, upgrade rollbacks, and package isolation (sandboxing).

Nix’s package isolation (sandboxing) and reproducible builds and environments are particularly important for enabling advanced remote execution setups. With Nix, you can define the dependencies needed to work on a project in any language(s) in a single file. This allows anyone with Nix installed to spawn a shell with the necessary dependencies installed in a single command.

Nix’s purely functional nature means that it makes changes in a very self-contained way. All packages installed by Nix live in the Nix store, usually the /nix/store directory. Packages are installed in folders with names that contain a hash of the package’s dependencies, and symlinks are created in paths like ~/.nix-profile/bin. This enables features like rollbacks and means that upgrading (or uninstalling) one package won’t affect your other packages.

In the context of remote execution setups, this means that you can have a high degree of confidence that the environment in which your code is being executed is exactly as you specified it, regardless of where that execution is taking place. This hermeticity is crucial for ensuring the reliability and reproducibility of remote execution.

To get started with Nix, you can install it seamlessly on most platforms. Once installed, you can start defining your project’s dependencies in a shell.nix file and use the nix-shell command to spawn a shell with those dependencies installed.

For a deeper understanding of the power of Nix, you may find the following references helpful:

• An Introduction to Nix
• First Steps with Nix