This is the Zephyr RTOS meta tool, west.

https://docs.zephyrproject.org/latest/guides/west/index.html

Installation

Using pip:

pip3 install west

(Use pip3 uninstall west to uninstall it.)

Basic Usage

West lets you manage multiple Git repositories under a single directory using a single file, called the west manifest file, or manifest for short. By default the manifest file is named west.yml. You use west init to set up this directory, then west update to fetch and/or update the repositories named in the manifest.

By default, west uses upstream Zephyr's manifest file, but west doesn't care if the manifest repository is zephyr or not. You can and are encouraged to make your own manifest repositories to meet your needs.

For more details, see the West guide in the Zephyr documentation.

Example usage using the upstream manifest file:

mkdir zephyrproject && cd zephyrproject
west init
west update

What just happened:

• west init clones the upstream west manifest repository, which in this case is the zephyr repository. The manifest repository contains west.yml, a YAML description of the Zephyr installation, including Git repositories and other metadata.
• west update clones the other repositories named in the manifest file, creating working trees in the installation directory zephyrproject.

Use west init -m to specify another manifest repository. Use --mr to use a revision to inialize from; if not given, the remote's default branch is used. Use --mf to use a manifest file other than west.yml.

Additional Commands

West has multiple sub-commands. After running west init, you can run them from anywhere under zephyrproject.

For a list of available commands, run west -h. Get help on a command with west <command> -h.

West is extensible: you can add new commands to west without modifying its source code. See Extensions in the documentation for details.

Hacking on West

This section contains notes for getting started developing west itself.

pip offers many different ways to (download and) install Python software. Below are common ways relevant to west; for a complete list check https://pip.pypa.io/en/stable/topics/

Quick Install

If you are not interested in source code and git history, GitHub offers pip the ability to download and install a .zip archive of any random version with a single command. This allows testing work in progress very quickly. Examples:

pip3 uninstall west
# Pull request 830
pip3 install --dry-run https://github.com/zephyrproject-rtos/west/archive/pull/830/head.zip
# Release v1.4
pip3 install https://github.com/zephyrproject-rtos/west/archive/v1.4-branch.zip
# Someone's random version
pip3 install https://github.com/someone_you_trust/west/archive/some_branch_or_tag.zip

Warning: never install software from people or locations you do not trust!

Editable Install

To run west "live" from the current source code tree, run this command from the top level directory in the west repository:

pip3 install -e .

This is useful if you are actively working on west and don't want to re-package and install a wheel each time you run it.

Creating a wheel package

You can create a wheel package and distribute it to others.

To build the west wheel file:

# Using uv
uv build

# Without uv
pip3 install --upgrade build
python -m build

This will create a file named dist/west-x.y.z-py3-none-any.whl, where x.y.z is the current version in setup.py.

To install the wheel:

pip3 install -U dist/west-x.y.z-py3-none-any.whl

You can pip3 uninstall west to remove this wheel before re-installing the version from PyPI, etc.

Running the Tests

First, install the dependencies:

# Using uv
uv sync --frozen

# Using pip (requires v25.1 or newer)
# Recommended in an active virtual environment
pip3 install --group dev

Then, run the tests (from the project's top level directory):

# Run the full test suite with uv (recommended)
uv run poe all

# Or run the full test suite with poe directly.
# (recommended in an active virtual environment)
poe all

# Run only the pytest tests (against the local worktree)
pytest

The all target from poe runs multiple tasks sequentially. Use poe -h to get a list of all available tasks. You can pass arguments to any poe task, which are forwarded to the underlying command. This is especially helpful when you want to run only specific tests to save time. Examples:

# Run a subset of tests (file)
poe test tests/test_project.py

# Run a single test
poe test tests/test_project.py::test_workspace

# Run the ``test_update_narrow()`` code with ``pdb`` (but _not_ the
# west code which is running in subprocesses)
poe test --exitfirst --trace -k test_update_narrow

# Run all tests with "import" in their name and let them log to the
# current terminal
poe test -k import --capture=no