reuse is a tool for compliance with the REUSE recommendations.
Source code: https://github.com/fsfe/reuse-tool
Copyright and licensing is difficult, especially when reusing software from different projects that are released under various different licenses. REUSE was started by the Free Software Foundation Europe (FSFE) to provide a set of recommendations to make licensing your Free Software projects easier. Not only do these recommendations make it easier for you to declare the licenses under which your works are released, but they also make it easier for a computer to understand how your project is licensed.
As a short summary, the recommendations are threefold:
Choose and provide licenses
Add copyright and licensing information to each file
Confirm REUSE compliance
You are recommended to read our tutorial for a step-by-step guide through these three steps. The FAQ covers basic questions about licensing, copyright, and more complex use cases. Advanced users and integrators will find the full specification helpful.
This tool exists to facilitate the developer in complying with the above recommendations.
There are other tools that have a lot more features and functionality surrounding the analysis and inspection of copyright and licenses in software projects. The REUSE helper tool, on the other hand, is solely designed to be a simple tool to assist in compliance with the REUSE recommendations.
Installation via package managers (Recommended)
There are packages available for easy install on some operating systems. You are welcome to help us package this tool for more distributions!
Arch Linux: reuse
GNU Guix: reuse
An automatically generated list can be found at repology.org, without any guarantee for completeness.
Install and run via pipx (Recommended)
pipx run reuse lint
pipx automatically isolates reuse into its own Python virtualenv, which means that it won’t interfere with other Python packages, and other Python packages won’t interfere with it.
If you want to be able to use reuse without prepending it with
pipx run every
time, install it globally like so:
pipx install reuse
reuse will then be available in
~/.local/bin, which must be added to your
Installation via pip
To install reuse, you need to have the following pieces of software on your computer:
You then only need to run the following command:
pip3 install --user reuse
After this, make sure that
~/.local/bin is in your
$PATH. On Windows, the
required path for your environment may look like
%USERPROFILE%\AppData\Roaming\Python\Python39\Scripts, depending on the Python
version you have installed.
To update reuse, run this command:
pip3 install --user --upgrade reuse
For full functionality, the following pieces of software are recommended:
Installation from source
You can also install this tool from the source code, but we recommend the methods above for easier and more stable updates. Please make sure the requirements for the installation via pip are present on your machine.
python3 setup.py install
First, read the REUSE tutorial. In a nutshell:
Put your licenses in the
Add a comment header to each file that says
SPDX-License-Identifier: GPL-3.0-or-later, and
SPDX-FileCopyrightText: $YEAR $NAME. You can be flexible with the format, just make sure that the line starts with
Verify your work using this tool.
Example of header:
# SPDX-FileCopyrightText: 2017 Free Software Foundation Europe e.V. <https://fsfe.org> # # SPDX-License-Identifier: CC-BY-SA-4.0
To check against the recommendations, use
~/Projects/reuse-tool $ reuse lint [...] Congratulations! Your project is compliant with version 3.0 of the REUSE Specification :-)
This tool can do various more things, detailed in the documentation. Here a short summary:
addheader— Add copyright and/or licensing information to the header of a file.
download— Download the specified license into the
init— Set up the project for REUSE compliance.
lint— Verify the project for REUSE compliance.
spdx— Generate an SPDX Document of all files in the project.
supported-licenses— Prints all licenses supported by REUSE.
Run in Docker
fsfe/reuse Docker image is available on
Docker Hub. With it, you can easily
include REUSE in CI/CD processes. This way, you can check for REUSE compliance
for each build. In our resources for developers
you can learn how to integrate the REUSE tool in Drone, Travis, GitHub, or
You can run the helper tool simply by providing the command you want to run
spdx). The image’s working directory is
/data by default. So
if you want to lint a project that is in your current working directory, you can
mount it on the container’s
/data directory, and tell the tool to lint. That
looks a little like this:
docker run --rm --volume $(pwd):/data fsfe/reuse lint
You can also provide additional arguments, like so:
docker run --rm --volume $(pwd):/data fsfe/reuse --include-submodules spdx -o out.spdx
There are a number of tags available:
latestis the most recent stable release.
masterbranch of this repository. Up-to-date, but potentially unstable.
latest-extrahas a few extra packages installed, currently
latest-debianis based on
python:slim. It is larger, but may be better suited for license compliance.
Run as pre-commit hook
repos: - repo: https://github.com/fsfe/reuse-tool rev: latest hooks: - id: reuse
pre-commit install. Now, every time you commit,
reuse lint is run
in the background, and will prevent your commit from going through if there was
Interaction within this project is covered by the FSFE’s Code of Conduct.
Starting local development is very simple, just execute the following commands:
git clone email@example.com:fsfe/reuse-tool.git cd reuse-tool/ python3 -mvenv venv source venv/bin/activate make develop
You need to run
make develop at least once to set up the virtualenv.
make help to see the available interactions.
This work is licensed under multiple licences. Because keeping this section up-to-date is challenging, here is a brief summary as of April 2020:
All original source code is licensed under GPL-3.0-or-later.
All documentation is licensed under CC-BY-SA-4.0.
Some configuration and data files are licensed under CC0-1.0.
Some code borrowed from spdx/tool-python is licensed under Apache-2.0.
For more accurate information, check the individual files.