Installation

Nerves requires a number of programs on your system to work. These include Erlang, Elixir, and a few tools for packaging firmware images. Nerves is actively used on MacOS and various Linux distributions. For Windows users, some people have had success running Linux in a virtual machine or using the Windows Subsystem for Linux available in Windows 10. If you have issues with any of the tooling after following the steps below, we recommend you reach out to us in the #nerves channel on the Elixir Slack.

Nerves requires that the Erlang version running on your development host be compatible with the Erlang version on the embedded target and also depends on features added in recent versions of Elixir (>= 1.4.0). Because it can be hard to manage these tool versions with sufficient granularity using operating system packages, it is recommended that you use ASDF to manage Erlang and Elixir installations. This tool works the same on its supported platforms, so you’ll find more details in the All Platforms section below.

MacOS

The easiest installation route on MacOS is to use Homebrew. Just run the following:

$ brew update
$ brew install fwup squashfs coreutils

Optionally, if you want to build custom Nerves Systems, you’ll also need to install Docker for Mac. After installing Docker for Mac, you will likely want to adjust the resource limits imposed on Docker, to allow it so successfully compile more complicated custom systems. Click the Docker icon in the top menu bar, then click Preferences > Advanced and allow Docker to use all of your CPUs and as much RAM as you think is reasonable for your machine (at least 6 GB). The more resources it has access to, the faster you can compile a custom Nerves system.

Now skip to the instructions for all platforms below.

Linux

First, install the fwup utility. Nerves uses fwup to create, distribute, and install firmware images of your programs. You can install fwup using the instructions found on the Installation Page. Installing the pre-built .deb or .rpm files is recommended.

The ssh-askpass package is also required on Linux so that the mix firmware.burn step will be able to use sudo to gain the required permission to write directly to an SD card:

$ sudo apt-get install ssh-askpass

Finally, install squashfs-tools using your distribution’s package manager. For example:

$ sudo apt-get install squashfs-tools

Optionally, if you want to build custom Nerves Systems, you need a few more build tools. Because Linux can build natively rather than inside a container, you need to have all of the dependencies installed on your host. On Debian and Ubuntu, run the following:

$ sudo apt-get install git g++ libssl-dev libncurses5-dev bc m4 make unzip cmake python

For other host Linux distributions, you will need to install equivalent packages, but we don’t have the exact list documented. If you’d like to help out, send us an improvement to this page and let us know what worked for you!

Now continue to the instructions for all platforms below.

All platforms

First, install the required versions of Erlang/OTP and Elixir using ADSF (more details at https://github.com/asdf-vm/asdf/blob/master/README.md#setup).

$ git clone https://github.com/asdf-vm/asdf.git ~/.asdf --branch v0.4.0
# The following steps are for BASH. If you’re using something else, do the
# equivalent for your shell.
$ echo -e '\n. $HOME/.asdf/asdf.sh' >> ~/.bash_profile
$ echo -e '\n. $HOME/.asdf/completions/asdf.bash' >> ~/.bash_profile # optional
$ source ~/.bash_profile
$ asdf plugin-add erlang https://github.com/asdf-vm/asdf-erlang.git
$ asdf plugin-add elixir https://github.com/asdf-vm/asdf-elixir.git
$ asdf install erlang 20.2 # This takes a while
$ asdf install elixir 1.5.2
$ asdf global erlang 20.2
$ asdf global elixir 1.5.2

It is important to update the versions of hex and rebar used by Elixir, even if you already had Elixir installed.

$ mix local.hex
$ mix local.rebar

If you have your own version of rebar in your path, be sure that it is up-to-date.

You can now add the nerves_bootstrap archive to your Mix environment. This archive allows Nerves to bootstrap the Mix environment, ensuring that your code is properly compiled using the right cross-compiler for the target. The nerves_bootstrap archive also includes a project generator, which you can use to create new Nerves projects. To install the nerves_bootstrap archive:

$ mix archive.install hex nerves_bootstrap

Once installed, you can upgrade nerves_bootstrap by running:

$ mix local.nerves