Install Flox

Verify your downloadYou can find the SHA256 checksums and SHA512 checksums for Flox 1.19.4 online.

Install with one command

The install script detects your OS and CPU architecture and installs Flox with the best method available on your machine. It supports MacOS, Debian, and Red Hat-based Linux distributions, on x86_64 and aarch64.

curl -fsSL https://get.flox.dev | sh

The script picks the install method that matches your platform:

On MacOS, it downloads and runs the .pkg installer.
On Debian and Ubuntu-family systems, it installs the .deb package with apt.
On Fedora and RHEL-family systems, it installs the .rpm package with dnf or yum.

If Flox is already installed, the script makes no changes and instead prints the upgrade command for your package manager.

Privileged commands are shown before they runBefore using sudo, the script prints the exact commands it is about to run with elevated privileges, so you know what you are agreeing to. You may be prompted for your sudo password.

Here is what an install looks like on Ubuntu:

$ curl -fsSL https://get.flox.dev | sh
==> Resolving the latest Flox version (stable channel)...
==> Installing Flox 1.14.0 for x86_64-linux
==> Downloading https://downloads.flox.dev/by-env/stable/deb/flox-1.14.0.x86_64-linux.deb
==> The following commands will be run with sudo:
    sudo apt-get install -y /tmp/flox-install.XXXXXX/flox-1.14.0.x86_64-linux.deb
==> Installing the .deb package with apt
...

Pin a channel or version

The script honors two environment variables:

curl -fsSL https://get.flox.dev | FLOX_CHANNEL=<channel> sh

curl -fsSL https://get.flox.dev | FLOX_VERSION=<version> sh

FLOX_CHANNEL (default stable) selects the release channel. FLOX_VERSION pins an exact version instead of the channel’s latest.

Verify Flox installation

If the following command returns without error then you’re ready to get started!

$ flox --version
1.14.0

The version you see might be different.

Upgrade existing Flox installation

The script does not upgrade an existing installation. Re-running it on a system that already has Flox prints the upgrade command for your package manager, for example:

sudo apt-get update && sudo apt-get install --only-upgrade flox

FAQ

What happens if Nix is already installed?

The script does not install Flox through Nix, and it will not modify your existing Nix installation. When it detects Nix (the nix command or a populated /nix/store), it stops and points you to the Nix tab, which covers installing Flox with an existing Nix.

Which systems does the script refuse to run on?

The script refuses to run on systems where the native packages are untested: immutable (ostree-based) distributions such as Fedora Silverblue or CoreOS, openSUSE/SLES, and RPM-family systems without dnf or yum. On those systems, install Nix first and then follow the Nix tab instructions.

Install Flox with the standalone .pkg installer or with Homebrew.

NoteWith either method you may be prompted for a sudo password or be asked if your terminal has authorization to modify disk contents.

This will replace an existing Nix installation

Flox will reconfigure an existing Nix installation. These changes are designed to improve the overall user experience and make the Nix installation more reliable and easier to support, but it’s worth noting that anyone wishing to revert to a “vanilla” Nix installation after installing Flox will need to re-install Nix.If you want retain full control of your Nix installation, see the Nix tab instructions.

When installing over a previous installation of Nix the Flox installation will:

Back out customizations made to the following files when Nix was installed:
- /etc/bashrc
- /etc/bash.bashrc
- /etc/profile.d/nix.sh
- /etc/zshrc
- /etc/zsh/zshrc
Overwrite the system-wide /etc/nix/nix.conf
(If applicable) convert the Nix installation to a multi-user install
Reconfigure the nix-daemon invocation

If you are installing over a previous installation of Nix we suggest that you install Flox to a test machine or VM to gain familiarity with it first.The version of Nix installed by Flox tracks the stable version of Nix in nixpkgs, occasionally adding additional backports or patches. Nix is usually updated monthly, although if Nix makes breaking changes, updates may be less frequent.

Pkg installer

Download and install the package that matches your machine’s architecture.

Download installer for Macs with
Apple Silicon
aarch64-darwin
Intel processors
x86_64-darwin
Double-click to install the downloaded file
Open a terminal window to continue below

Homebrew

In your terminal run:

brew install flox

Verify Flox installation

If the following command returns without error then you’re ready to get started!

$ flox --version
1.19.4

The version you see might be different.

Upgrade existing Flox installation

If you installed with the .pkg installer, download and install the latest package as described above. If you installed with Homebrew:

brew upgrade flox

For use on Debian, Ubuntu, and other Debian-based distributions.

NoteThe package will register a new source in /etc/apt/sources.list.d to enable upgrades via apt.

Download and install the package

Run the command for your system architecture:64-bit Intel/AMD:

curl -LO https://downloads.flox.dev/by-env/stable/deb/flox-1.19.4.x86_64-linux.deb
sudo apt install ./flox-1.19.4.x86_64-linux.deb

64-bit ARM:

curl -LO https://downloads.flox.dev/by-env/stable/deb/flox-1.19.4.aarch64-linux.deb
sudo apt install ./flox-1.19.4.aarch64-linux.deb

This will replace an existing Nix installation

When installing over a previous installation of Nix the Flox installation will:

Back out customizations made to the following files when Nix was installed:
- /etc/bashrc
- /etc/bash.bashrc
- /etc/profile.d/nix.sh
- /etc/zshrc
- /etc/zsh/zshrc
Overwrite the system-wide /etc/nix/nix.conf
(If applicable) convert the Nix installation to a multi-user install
Reconfigure the nix-daemon invocation

Verify Flox installation

If the following command returns without error then you’re ready to get started!

$ flox --version
1.19.4

The version you see might be different.

Upgrade existing Flox installation

sudo apt update;
sudo apt --only-upgrade install flox

For use on RedHat, CentOS, Amazon Linux, and other RPM-based distributions.

NoteThe rpm will register a package repository in /etc/yum.repos.d to enable upgrades. via yum, dnf and other compatible tools.

Download and install the package

Import the Flox archive keyring:

sudo rpm --import https://downloads.flox.dev/by-env/stable/rpm/flox-archive-keyring.asc

Run the command for your system architecture: 64-bit Intel/AMD:

curl -LO https://downloads.flox.dev/by-env/stable/rpm/flox-1.19.4.x86_64-linux.rpm
sudo rpm -ivh ./flox-1.19.4.x86_64-linux.rpm

64-bit ARM:

curl -LO https://downloads.flox.dev/by-env/stable/rpm/flox-1.19.4.aarch64-linux.rpm
sudo rpm -ivh ./flox-1.19.4.aarch64-linux.rpm

This will replace an existing Nix installation

When installing over a previous installation of Nix the Flox installation will:

Back out customizations made to the following files when Nix was installed:
- /etc/bashrc
- /etc/bash.bashrc
- /etc/profile.d/nix.sh
- /etc/zshrc
- /etc/zsh/zshrc
Overwrite the system-wide /etc/nix/nix.conf
(If applicable) convert the Nix installation to a multi-user install
Reconfigure the nix-daemon invocation

Verify Flox installation

If the following command returns without error then you’re ready to get started!

$ flox --version
1.19.4

The version you see might be different.

Upgrade existing Flox installation

sudo yum update flox

sudo dnf update flox

These instructions cover installing Flox on systems that already have Nix installed. Pick your setup:

Generic Nix

You keep full control of your Nix installation.

NixOS

Add Flox to your system configuration.

Determinate Nix

Not yet supported — uninstall it first.

Generic Nix

Which install method for existing Nix installation?Use the Flox installer for your system to allow some opinionated configuration of Nix, or use these generic Nix instructions for full control of your Nix installation.

Make sure you are running Nix version 2.18.0 or greater, then install Flox imperatively with nix profile install or declaratively as part of a flake-based configuration.

Install imperatively

Configure Substituters Add the following values to /etc/nix/nix.conf, taking care to merge them with any trusted-substituters or trusted-public-keys values that may already be defined:

/etc/nix/nix.conf

extra-trusted-substituters = https://cache.flox.dev
extra-trusted-public-keys = flox-cache-public-1:7F4OyH7ZCnFhcze3fJdfyXYLQw/aV7GEed86nQ7IsOs= floxhub-1:0QOAlcobcEvq1mqEf4qAYCaWnTTOXpyoRv/PmqfSixM=

Then restart the nix-daemon, if applicable:

Linux:

sudo systemctl stop nix-daemon.service
sudo systemctl restart nix-daemon.socket

MacOS:

sudo launchctl kickstart -k -p system/org.nixos.nix-daemon

Install Flox to your personal profile:

nix profile install \
      --experimental-features "nix-command flakes" \
      --accept-flake-config \
      'github:flox/flox/latest'

Install Flox to the system-wide default profile as root:

sudo -H nix profile install \
      --profile /nix/var/nix/profiles/default \
      --experimental-features "nix-command flakes" \
      --accept-flake-config \
      'github:flox/flox/latest'

On error

If you encounter the following error then please upgrade your Nix installation (and in particular the running nix-daemon) to the latest version (minimum supported version is 2.18.0):

error: builder for '/nix/store/35l1qqyis11y88ic0cp3yxgv3286l4pb-flox-0.0.2-r295.drv' failed with exit code 1;
       last 1 log lines:
       > error: attribute 'requisites' missing

If you encounter any other errors with the installer please report the bug by way of discourse, including a full copy of the command invoked and error encountered.

Install declaratively

The following example is for a Nix darwin installation. You may need to modify inputs to match your system.

Using Flox's binary cache

Flox hosts a binary cache for its packages, that can be added to your /etc/nix/nix.conf file. We recommend doing this if you are installing Flox system-wide.

/etc/nix/nix.conf

extra-trusted-substituters = https://cache.flox.dev
extra-trusted-public-keys = flox-cache-public-1:7F4OyH7ZCnFhcze3fJdfyXYLQw/aV7GEed86nQ7IsOs= floxhub-1:0QOAlcobcEvq1mqEf4qAYCaWnTTOXpyoRv/PmqfSixM=

Or, to your flake configuration by using the nixConfig attribute. This will ensure that Flox’s binary cache is used for all operation within that flake.

flake.nix

{
    nixConfig = {
        extra-trusted-substituters = ["https://cache.flox.dev"];
        extra-trusted-public-keys = [
            "flox-cache-public-1:7F4OyH7ZCnFhcze3fJdfyXYLQw/aV7GEed86nQ7IsOs="
            "floxhub-1:0QOAlcobcEvq1mqEf4qAYCaWnTTOXpyoRv/PmqfSixM="
        ];
    };
}

Note that if you don’t add either of these options, Flox will be built from source, together with a patched version of Nix. Which might take a while on less powerful systems.

{
  description = "Example Darwin system flake";

  nixConfig = {
    extra-trusted-substituters = ["https://cache.flox.dev"];
    extra-trusted-public-keys = [
      "flox-cache-public-1:7F4OyH7ZCnFhcze3fJdfyXYLQw/aV7GEed86nQ7IsOs="
      "floxhub-1:0QOAlcobcEvq1mqEf4qAYCaWnTTOXpyoRv/PmqfSixM="
    ];
  };

  inputs = {
    nixpkgs = {
      url = "github:NixOS/nixpkgs/nixpkgs-23.11-darwin";
    };
    nix-darwin = {
      url = "github:LnL7/nix-darwin";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    flox = {
      url = "github:flox/flox/latest";
    };
  };

  outputs = inputs@{ self, nix-darwin, nixpkgs, flox }:
  let
    configuration = { pkgs, ... }: {
      environment.systemPackages =
        [ pkgs.__YOUR_PACKAGES__
          inputs.flox.packages.${pkgs.system}.default
        ];

      nix.settings = {
        experimental-features = "nix-command flakes";
        extra-substituters = [
          "https://cache.flox.dev"
        ];
        extra-trusted-public-keys = [
          "flox-cache-public-1:7F4OyH7ZCnFhcze3fJdfyXYLQw/aV7GEed86nQ7IsOs="
          "floxhub-1:0QOAlcobcEvq1mqEf4qAYCaWnTTOXpyoRv/PmqfSixM="
        ];
      };

      __YOUR_CONFIG__
    };
  in
  {
    darwinConfigurations."__YOUR_HOST__" = nix-darwin.lib.darwinSystem {
      modules = [ configuration ];
      specialArgs = { inherit inputs; };
    };
  };
}

Run nix-darwin to install the configuration and packages you’ve declared. This is an example on nix-darwin: nix run nix-darwin -- switch --flake ~/path/to/flake

NixOS

On NixOS, configure /etc/nixos/configuration.nix to add the lines:

/etc/nixos/configuration.nix

nix.settings.extra-trusted-substituters = [ "https://cache.flox.dev" ];
nix.settings.extra-trusted-public-keys = [
  "flox-cache-public-1:7F4OyH7ZCnFhcze3fJdfyXYLQw/aV7GEed86nQ7IsOs="
  "floxhub-1:0QOAlcobcEvq1mqEf4qAYCaWnTTOXpyoRv/PmqfSixM="
];

… and then invoke:

sudo nixos-rebuild switch

Then install Flox:

Install to your personal profile:

nix profile install \
      --experimental-features "nix-command flakes" \
      --accept-flake-config \
      'github:flox/flox/latest'

Install Flox to the system-wide default profile as root:

sudo -H nix profile install \
      --profile /nix/var/nix/profiles/default \
      --experimental-features "nix-command flakes" \
      --accept-flake-config \
      'github:flox/flox/latest'

Determinate Nix

Flox hasn’t been tested alongside Determinate Nix, which installs its own nix-daemon fork. The supported path is to uninstall Determinate Nix first, then install Flox fresh using one of the other methods on this page.

Uninstall Determinate Nix:

/nix/nix-installer uninstall

Then pick the tab above for your OS (or follow the Generic Nix instructions above if you’d rather install upstream Nix yourself first).

Verify Flox installation

If the following command returns without error then you’re ready to get started!

$ flox --version
1.19.4

The version you see might be different.

Upgrade existing Flox installation

If you’ve installed Flox to the system-wide default profile

sudo -H nix profile upgrade \
        --profile /nix/var/nix/profiles/default \
        --experimental-features "nix-command flakes" \
        --accept-flake-config \
        '.*flox'

Or, if you’ve installed Flox to your own personal profile

nix profile upgrade \
    --experimental-features "nix-command flakes" \
    --accept-flake-config \
    '.*flox'

Or, if you’ve declared Flox using a flake, run nix flake update.On NixOS, if you’ve declared Flox in your system configuration, update the flake input and run sudo nixos-rebuild switch.

If you have Docker installed then you can also run flox in a container to try it out before installing on your system.

Invoke Flox container

docker run --pull always --rm -it ghcr.io/flox/flox

Verify Flox installation

If the following command returns without error then you’re ready to get started!

$ flox --version
1.19.4

The version you see might be different.

Support for WSL 2 is experimental.

Install WSL 2Please install and configure WSL version 2 as described in the Microsoft Learn Install WSL guide before installing Flox. Please also ensure the state (whether the distribution is running or stopped) is running.Note that installation will fail on WSL 1.

Microsoft provides several Linux distributions for use with WSL and will use Ubuntu by default. Use the following commands to run and manage your chosen distribution:

list installed distributions: wsl --list
run specified distribution: wsl --distribution <name>
list all available distributions: wsl --list --online
install distribution: wsl --install -d <name>
terminate distribution: wsl --terminate <name>
unregister and delete distribution: wsl --unregister <name>

Supported distributions

Please follow the steps below to install Flox on the distribution of your choice:

Ubuntu

Download and install the package

Run the command for your system architecture:64-bit Intel/AMD:

curl -LO https://downloads.flox.dev/by-env/stable/deb/flox-1.19.4.x86_64-linux.deb
sudo dpkg -i ./flox-1.19.4.x86_64-linux.deb

64-bit ARM:

curl -LO https://downloads.flox.dev/by-env/stable/deb/flox-1.19.4.aarch64-linux.deb
sudo dpkg -i ./flox-1.19.4.aarch64-linux.deb

Debian

Install prerequisites

sudo apt-get install policycoreutils semodule-utils tar wget xz-utils

Download and install the package

Run the command for your system architecture:64-bit Intel/AMD:

curl -LO https://downloads.flox.dev/by-env/stable/deb/flox-1.19.4.x86_64-linux.deb
sudo dpkg -i ./flox-1.19.4.x86_64-linux.deb

64-bit ARM:

curl -LO https://downloads.flox.dev/by-env/stable/deb/flox-1.19.4.aarch64-linux.deb
sudo dpkg -i ./flox-1.19.4.aarch64-linux.deb

OracleLinux_8_5

Install prerequisites

sudo yum install tar xz

Download and install the package

Run the command for your system architecture:64-bit Intel/AMD:

curl -LO https://downloads.flox.dev/by-env/stable/rpm/flox-1.19.4.x86_64-linux.rpm
sudo rpm -ivh ./flox-1.19.4.x86_64-linux.rpm

64-bit ARM:

curl -LO https://downloads.flox.dev/by-env/stable/rpm/flox-1.19.4.aarch64-linux.rpm
sudo rpm -ivh ./flox-1.19.4.aarch64-linux.rpm

Ignore warning about systemdYou will encounter the following warning during the installation:

---- warning! ------------------------------------------------------------------
We did not detect systemd on your system. With a multi-user install
without systemd you will have to manually configure your init system to
launch the Nix daemon after installation.

You can disregard this message as we will be configuring the nix-daemon to start automatically in the next section.

Configure `nix-daemon` to start on activation

Once Flox has been installed on your WSL distribution the nix-daemon will need to be automatically started as you start your WSL instance.Run the following command to add the necessary logic to invoke nix-daemon by way of your ~/.bashrc file:

cat >> ~/.bashrc <<EOF
( wsl.exe -d $WSL_DISTRO_NAME -u root service nix-daemon status 2>&1 >/dev/null ) || wsl.exe -d $WSL_DISTRO_NAME -u root service nix-daemon start
EOF

Then restart your WSL shell (or start another) and run the following command to ensure that the nix-daemon is working correctly:

nix --extra-experimental-features nix-command store ping

Verify Flox installation

If the following command returns without error then you’re ready to get started!

$ flox --version
1.19.4

The version you see might be different.

Upgrade existing Flox installation

Please follow the instructions provided on either the Debian or RPM tab (whichever matches the existing Linux Distribution installed with your WSL) to update to latest version of Flox.

​Install with one command

​Pin a channel or version

​Verify Flox installation

​Upgrade existing Flox installation

​FAQ

​Pkg installer

Apple Silicon

Intel processors

​Homebrew

​Verify Flox installation

​Upgrade existing Flox installation

​Download and install the package

​Verify Flox installation

​Upgrade existing Flox installation

​Download and install the package

​Verify Flox installation

​Upgrade existing Flox installation

Generic Nix

NixOS

Determinate Nix

​Generic Nix

​Install imperatively

​Install declaratively

​NixOS

​Determinate Nix

​Verify Flox installation

​Upgrade existing Flox installation

​Invoke Flox container

​Verify Flox installation

​Supported distributions

​Download and install the package

​Download and install the package

​Download and install the package

​Configure nix-daemon to start on activation

​Verify Flox installation

​Upgrade existing Flox installation

Install with one command

Pin a channel or version

Verify Flox installation

Upgrade existing Flox installation

FAQ

Pkg installer

Homebrew

Verify Flox installation

Upgrade existing Flox installation

Download and install the package

Verify Flox installation

Upgrade existing Flox installation

Download and install the package

Verify Flox installation

Upgrade existing Flox installation

Generic Nix

Install imperatively

Install declaratively

NixOS

Determinate Nix

Verify Flox installation

Upgrade existing Flox installation

Invoke Flox container

Verify Flox installation

Supported distributions

Download and install the package

Download and install the package

Download and install the package

Configure `nix-daemon` to start on activation

Verify Flox installation

Upgrade existing Flox installation