This is the documentation for the latest (main) development branch of Zephyr. If you are looking for the documentation of previous releases, use the drop-down menu on the left and select the desired version.

Getting Started Guide

Follow this guide to:

  • Set up a command-line Zephyr development environment on Ubuntu, macOS, or Windows (instructions for other Linux distributions are discussed in Install Linux Host Dependencies)

  • Get the source code

  • Build, flash, and run a sample application

Select and Update OS

Click the operating system you are using.

This guide covers Ubuntu version 18.04 LTS and later.

sudo apt update
sudo apt upgrade

Install dependencies

Next, you’ll install some host dependencies using your package manager.

The current minimum required version for the main dependencies are:


Min. Version





Devicetree compiler


  1. Download, inspect and execute the Kitware archive script to add the Kitware APT repository to your sources list. A detailed explanation of can be found here kitware third-party apt repository:

    sudo bash
  2. Use apt to install the required dependencies:

    sudo apt install --no-install-recommends git cmake ninja-build gperf \
      ccache dfu-util device-tree-compiler wget \
      python3-dev python3-pip python3-setuptools python3-tk python3-wheel xz-utils file \
      make gcc gcc-multilib g++-multilib libsdl2-dev
  3. Verify the versions of the main dependencies installed on your system by entering:

    cmake --version
    python3 --version
    dtc --version

    Check those against the versions in the table in the beginning of this section. Refer to the Install Linux Host Dependencies page for additional information on updating the dependencies manually.

Get Zephyr and install Python dependencies

Next, clone Zephyr and its modules into a new west workspace named zephyrproject. You’ll also install Zephyr’s additional Python dependencies.

Python is used by the west meta-tool as well as by many scripts invoked by the build system. It is easy to run into package incompatibilities when installing dependencies at a system or user level. This situation can happen, for example, if working on multiple Zephyr versions at the same time. For this reason it is suggested to use Python virtual environments.

  1. Install west, and make sure ~/.local/bin is on your PATH environment variable:

    pip3 install --user -U west
    echo 'export PATH=~/.local/bin:"$PATH"' >> ~/.bashrc
    source ~/.bashrc
  2. Get the Zephyr source code:

    west init ~/zephyrproject
    cd ~/zephyrproject
    west update
  3. Export a Zephyr CMake package. This allows CMake to automatically load boilerplate code required for building Zephyr applications.

    west zephyr-export
  4. Zephyr’s scripts/requirements.txt file declares additional Python dependencies. Install them with pip3.

    pip3 install --user -r ~/zephyrproject/zephyr/scripts/requirements.txt

Install a Toolchain

A toolchain provides a compiler, assembler, linker, and other programs required to build Zephyr applications.

The Zephyr Software Development Kit (SDK) contains toolchains for each of Zephyr’s supported architectures. It also includes additional host tools, such as custom QEMU binaries and a host compiler.

  1. Download the latest SDK installer:

    cd ~
  2. Run the installer, installing the SDK in ~/zephyr-sdk-0.13.1:

    chmod +x
    ./ -- -d ~/zephyr-sdk-0.13.1


    It is recommended to install the Zephyr SDK at one of the following locations:

    • $HOME/zephyr-sdk[-x.y.z]

    • $HOME/.local/zephyr-sdk[-x.y.z]

    • $HOME/.local/opt/zephyr-sdk[-x.y.z]

    • $HOME/bin/zephyr-sdk[-x.y.z]

    • /opt/zephyr-sdk[-x.y.z]

    • /usr/zephyr-sdk[-x.y.z]

    • /usr/local/zephyr-sdk[-x.y.z]

    where [-x.y.z] is optional text, and can be any text, for example -0.13.1.

    If installing the Zephyr SDK outside any of those locations, please read: Install the Zephyr Software Development Kit (SDK)

    You cannot move the SDK directory after you have installed it.

  3. Install udev rules, which allow you to flash most Zephyr boards as a regular user:

    sudo cp ~/zephyr-sdk-0.13.1/sysroots/x86_64-pokysdk-linux/usr/share/openocd/contrib/60-openocd.rules /etc/udev/rules.d
    sudo udevadm control --reload

Build the Blinky Sample


Blinky is compatible with most, but not all, Supported Boards. If your board does not meet Blinky’s Requirements, then Hello World is a good alternative.

Build the Blinky with west build, changing <your-board-name> appropriately for your board:

cd ~/zephyrproject/zephyr
west build -p auto -b <your-board-name> samples/basic/blinky

The -p auto option automatically cleans byproducts from a previous build if necessary, which is useful if you try building another sample.

Flash the Sample

Connect your board, usually via USB, and turn it on if there’s a power switch. If in doubt about what to do, check your board’s page in Supported Boards.

Then flash the sample using west flash:

west flash

You may need to install additional host tools required by your board. The west flash command will print an error if any required dependencies are missing.

If you’re using blinky, the LED will start to blink as shown in this figure:


Phytec reel_board running blinky

Next Steps

Here are some next steps for exploring Zephyr:

Asking for Help

You can ask for help on a mailing list or on Discord. Please send bug reports and feature requests to GitHub.

How to Ask


Please search this documentation and the mailing list archives first. Your question may have an answer there.

Don’t just say “this isn’t working” or ask “is this working?”. Include as much detail as you can about:

  1. What you want to do

  2. What you tried (commands you typed, etc.)

  3. What happened (output of each command, etc.)

Use Copy/Paste

Please copy/paste text instead of taking a picture or a screenshot of it. Text includes source code, terminal commands, and their output.

Doing this makes it easier for people to help you, and also helps other users search the archives.

When copy/pasting more than 5 lines of text into Discord, create a snippet using three backticks to delimit the snippet.