Packaging guidelines

Thank you very much for packaging vdirsyncer! The following guidelines should help you to avoid some common pitfalls.

If you find yourself needing to patch anything, or going in a different direction, please open an issue so we can also address in a way that works for everyone. Otherwise we get bug reports for code or scenarios that don’t exist in upstream vdirsycner.

Obtaining the source code

The main distribution channel is PyPI, and source tarballs can be obtained there. We mirror the same package tarball and wheel as GitHub releases. Please do not confuse these with the auto-generated GitHub “Source Code” tarball. Those are missing some important metadata and your build will fail.

We give each release a tag in the git repo. If you want to get notified of new releases, GitHub’s feed is a good way.

Tags will be signed by the maintainer who is doing the release (starting with 0.16.8), and generation of the tarball and wheel is done by CI. Hence, only the tag itself is signed.

Dependency versions

As with most Python packages, denotes the dependencies of vdirsyncer. It also contains lower-bound versions of each dependency. Older versions will be rejected by the testsuite.


Everything testing-related goes through the Makefile in the root of the repository or PyPI package. Trying to e.g. run pytest directly will require a lot of environment variables to be set (for configuration) and you probably don’t want to deal with that.

You can install the all development dependencies with:

make install-dev

You probably don’t want this since it will use pip to download the dependencies. Alternatively you can find the testing dependencies in test-requirements.txt, again with lower-bound version requirements.

You also have to have vdirsyncer fully installed at this point. Merely cd-ing into the tarball will not be sufficient.

Running the tests happens with:


Hypothesis will randomly generate test input. If you care about deterministic tests, set the DETERMINISTIC_TESTS variable to "true":


There are a lot of additional variables that allow you to test vdirsyncer against a particular server. Those variables are not “stable” and may change drastically between minor versions. Just don’t use them, you are unlikely to find bugs that vdirsyncer’s CI hasn’t found.


Using Sphinx you can generate the documentation you’re reading right now in a variety of formats, such as HTML, PDF, or even as a manpage. That said, I only take care of the HTML docs’ formatting.

You can find a list of dependencies in docs-requirements.txt. Again, you can install those using pip with:

pip install -r docs-requirements.txt

Then change into the docs/ directory and build whatever format you want using the Makefile in there (run make for the formats you can build).

Contrib files

Reference systemd.service and systemd.timer unit files are provided. It is recommended to install this if your distribution is systemd-based.