Contributions are welcome, and they are greatly appreciated! Every little bit helps, and credit will always be given.

Bug reports

When reporting a bug please include:

  • Your operating system name and version.

  • Any details about your local setup that might be helpful in troubleshooting.

  • Detailed steps to reproduce the bug.

Documentation improvements

snps could always use more documentation, whether as part of the official snps docs, in docstrings, or even on the web in blog posts, articles, and such. See below for info on how to generate documentation.

Feature requests and feedback

The best way to send feedback is to file an issue at

If you are proposing a feature:

  • Explain in detail how it would work.

  • Keep the scope as narrow as possible, to make it easier to implement.

  • Remember that this is a volunteer-driven project, and that code contributions are welcome :)


To set up snps for local development:

  1. Fork snps (look for the “Fork” button).

  2. Clone your fork locally:

    $ git clone
  3. Create a branch for local development from the develop branch:

    $ cd snps
    $ git checkout develop
    $ git checkout -b name-of-your-bugfix-or-feature develop
  4. Setup a development environment:

    $ pip install pipenv
    $ pipenv install --dev
  5. When you’re done making changes, run all the tests with:

    $ pipenv run pytest --cov-report=html --cov=snps tests


    Downloads during tests are disabled by default. To enable downloads, set the environment variable DOWNLOADS_ENABLED=true.


    If you receive errors when running the tests, you may need to specify the temporary directory with an environment variable, e.g., TMPDIR="/path/to/tmp/dir".


    After running the tests, a coverage report can be viewed by opening htmlcov/index.html in a browser.

  6. Check code formatting:

    $ pipenv run black --check --diff .
  7. Commit your changes and push your branch to GitHub:

    $ git add .
    $ git commit -m "Your detailed description of your changes."
    $ git push origin name-of-your-bugfix-or-feature
  8. Submit a pull request through the GitHub website.

Pull request guidelines

If you need some code review or feedback while you’re developing the code, just make the pull request.

For merging, you should:

  1. Ensure tests pass.

  2. Update documentation when there’s new API, functionality, etc.

  3. Add yourself to CONTRIBUTORS.rst if you’d like.


After the development environment has been setup, documentation can be generated via the following command:

$ pipenv run sphinx-build -T -E -D language=en docs docs/_build

Then, the documentation can be viewed by opening docs/_build/index.html in a browser.