Apache Abdera moved into the Attic in March 2017. Apache Abdera was a project to build a functionally-complete, high-performance implementation of the IETF Atom Syndication Format (RFC 4287) and Atom Publishing Protocol (RFC 5023) specifications.
As with any project in the Attic - if you should choose to fork Abdera outside of Apache, please let us know so we can link to your project.