If you already have a contribution in mind you can find the project repositories on GitHub.
- Get in contact in the mailing lists
- Join us on IRC: #freenet on chat.freenode.net
- Report issues in the bug tracker hosted by MantisHub
The Wiki contains a list of freenet-related projects and documentation of the Freenet Client Protocol for using Freenet from external programs.
We're happy to accept pull requests on GitHub as well as patches sent under a pseudonym through Freenet forums such as FMS.