# Nix Installer > **`nix-installer` is pre-release and experimental.** Don't run it on machines you care about. `nix-installer` is an opinionated, experimental Nix installer. > Try it on a machine/VM you don't care about! > > ```bash > curl -L https://install.determinate.systems/nix | sh -s -- install > ``` ## Status `nix-installer` is **pre-release and experimental**. It is not ready for you to use! *Please* don't use it on a machine you are not planning to obliterate! Planned support: * [x] Multi-user x86_64 Linux with systemd init, no SELinux * [x] Multi-user aarch64 Linux with systemd init, no SELinux * [x] Multi-user x86_64 MacOS + Note: User deletion is currently unimplemented, you need to use a user with a secure token and `dscl . -delete /Users/_nixbuild*` where `*` is each user number. * [x] Multi-user aarch64 MacOS + Note: User deletion is currently unimplemented, you need to use a user with a secure token and `dscl . -delete /Users/_nixbuild*` where `*` is each user number. * [x] Valve Steam Deck * [ ] Multi-user x86_64 Linux with systemd init, with SELinux * [ ] Multi-user aarch64 Linux with systemd init, with SELinux * [ ] Single-user x86_64 Linux * [ ] Single-user aarch64 Linux * [ ] Others... ## Installation Differences Differing from the current official [Nix](https://github.com/NixOS/nix) installer scripts: * Nix is installed with the `nix-command` and `flakes` features enabled in the `nix.conf` * `nix-installer` stores an installation receipt (for uninstalling) at `/nix/receipt.json` as well as a copy of the install binary at `/nix/nix-installer` ## Motivations The current Nix installer scripts do an excellent job, however they are difficult to maintain. Subtle differences in the shell implementations, and certain characteristics of bash scripts make it difficult to make meaningful changes to the installer. Our team wishes to experiment with the idea of an installer in a more structured language and see if this is a worthwhile alternative. Along the way, we are also exploring a few other ideas, such as: * offering users a chance to review an accurate, calculated install plan * having 'planners' which can create appropriate install plans * keeping an installation receipt for uninstallation * offering users with a failing install the chance to do a best-effort revert * doing whatever tasks we can in parallel So far, our explorations have been quite fruitful, so we wanted to share and keep exploring. ## Building Since you'll be using `nix-installer` to install Nix on systems without Nix, the default build is a static binary. Build it on a system with Nix: ```bash nix build github:determinatesystems/nix-installer ``` Then copy the `result/bin/nix-installer` to the machine you wish to run it on. ## Installing Install Nix with the default planner and options: ```bash ./nix-installer install ``` > `nix-installer` will elevate itself if it is not run as `root` using `sudo`. If you use `doas` or `please` you may need to elevate `nix-installer` yourself. To observe verbose logging, either use `nix-installer -v`, this tool [also respects the `RUST_LOG` environment](https://docs.rs/tracing-subscriber/latest/tracing_subscriber/filter/struct.EnvFilter.html#directives). (Eg `RUST_LOG=nix_installer=trace nix-installer`). `nix-installer` installs Nix by following a *plan* made by a *planner*. Review the available planners: ```bash $ ./nix-installer install --help Execute an install (possibly using an existing plan) To pass custom options, select a planner, for example `nix-installer install linux-multi --help` Usage: nix-installer install [OPTIONS] [PLAN] nix-installer install Commands: linux-multi A standard Linux multi-user install darwin-multi A standard MacOS (Darwin) multi-user install steam-deck A specialized install suitable for the Valve Steam Deck console help Print this message or the help of the given subcommand(s) # ... ``` Planners have their own options and defaults, sharing most of them in common: ```bash $ ./nix-installer install linux-multi --help A standard Linux multi-user install Usage: nix-installer install linux-multi [OPTIONS] Options: --channels Channel(s) to add [env: NIX_INSTALLER_CHANNEL=] [default: nixpkgs=https://nixos.org/channels/nixpkgs-unstable] --no-confirm -v, --verbose... Enable debug logs, -vv for trace --explain --logger Which logger to use [default: compact] [possible values: compact, full, pretty, json] --modify-profile Modify the user profile to automatically load nix [env: NIX_INSTALLER_NO_MODIFY_PROFILE=] --daemon-user-count Number of build users to create [env: NIX_INSTALLER_DAEMON_USER_COUNT=] [default: 32] --nix-build-group-name The Nix build group name [env: NIX_INSTALLER_NIX_BUILD_GROUP_NAME=] [default: nixbld] --nix-build-group-id The Nix build group GID [env: NIX_INSTALLER_NIX_BUILD_GROUP_ID=] [default: 3000] --nix-build-user-prefix The Nix build user prefix (user numbers will be postfixed) [env: NIX_INSTALLER_NIX_BUILD_USER_PREFIX=] [default: nixbld] --nix-build-user-id-base The Nix build user base UID (ascending) [env: NIX_INSTALLER_NIX_BUILD_USER_ID_BASE=] [default: 3000] --nix-package-url The Nix package URL [env: NIX_INSTALLER_NIX_PACKAGE_URL=] [default: https://releases.nixos.org/nix/nix-2.12.0/nix-2.12.0-x86_64-linux.tar.xz] --extra-conf Extra configuration lines for `/etc/nix.conf` [env: NIX_INSTALLER_EXTRA_CONF=] --force Forcibly recreate files it finds existing [env: NIX_INSTALLER_FORCE=] -h, --help Print help information ``` Planners can be configured via environment variable, or by the command arguments. ```bash $ NIX_INSTALLER_DAEMON_USER_COUNT=4 ./nix-installer install linux-multi --nix-build-user-id-base 4000 --help ``` ## Uninstalling You can remove a `nix-installer`-installed Nix by running ```bash /nix/nix-installer uninstall ``` ## As a library > We haven't published to [crates.io](https://crates.io/) yet. We plan to for 0.0.1. Add `nix-installer` to your dependencies: ```bash cargo add --git https://github.com/DeterminateSystems/nix-installer ``` > **Building a CLI?** Check out the `cli` feature flag for `clap` integration. Then it's possible to review the documentation: ```bash cargo doc --open -p nix-installer ``` Documentation is also available via `nix` build: ```bash nix build github:DeterminateSystems/nix-installer#nix-installer.doc firefox result-doc/nix-installer/index.html ``` ## As a Github Action You can use `nix-installer` as a Github action like so: ```yaml on: pull_request: push: branches: [main] jobs: lints: name: Build runs-on: ubuntu-22.04 steps: - uses: actions/checkout@v3 - name: Install Nix uses: DeterminateSystems/nix-installer@main with: # Allow the installed Nix to make authenticated Github requests. # If you skip this, you will likely get rate limited. github-token: ${{ secrets.GITHUB_TOKEN }} - name: Run `nix build` run: nix build . ```