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Submitting Contributions to GAP

The GAP group encourages users to make their GAP related work available to other users. There used to be two main categories of external contributions to GAP, those that have been formally accepted in a refereeing process, and those that are just deposited. However we stopped refereeing new packages in February 2024, and now only accept new deposited packages.

Irrespective of this, you may consider organizing and maybe distributing your code in the form of a GAP package. The page Information for GAP Package Authors give detailed advice how to do this.

Submitting Deposited Contributions

You are also invited to provide material that is not intended for formal refereeing. To tell us about such material, contact

We will then review your package for certain formal properties, and provide feedback based on that, with the expectation that after possibly some back and forth your contribution can be accepted.

Things we will check include technical aspects such as:

  • Does the package pass validation via ValidatePackageInfo?
  • Is it clearly distributed under a license compatible with GAP’s license (GPL 2)?
  • Does it have an appropriate website which is set up so that automatic updates are possible (i.e. are PackageInfoURL and ArchiveURL in PackageInfo.g valid)?
  • Does it specify a non-empty TestFile in its PackageInfo.g that can be used to verify that basic functionality of the package works?
  • Can it be loaded together with all other distributed packages without e.g. errors caused by multiple packages declaring global variables or functions with identical name but different content?

Besides these technical aspects we may consider questions such as

  • Does the package do what it claims to?
  • Is its functionality a significant addition to GAP?
  • Does the package interact smoothly with the existing GAP library and packages?
  • Does the package employ appropriate GAP functions and data structures?
  • Is the main documentation clear and complete enough?

This last point is especially important. The installation of the package must work as described in the installation guide. The package’s documentation should include straightforward and quick examples to help the user test the installation, the examples of the manual must really work the way the manual says, and the overall documentation should be organized sensibly.