Jakarta RESTful Web Services 
Jakarta RESTful Web Services provides a specification document, TCK and foundational API to develop web services following the Representational State Transfer (REST) architectural pattern.
Contributions are welcome, please sign the Eclipse Contributor Agreement before submitting PRs: https://www.eclipse.org/contribute/cla
Project page: https://projects.eclipse.org/projects/ee4j.jaxrs
Mailinglist: https://accounts.eclipse.org/mailing-list/jaxrs-dev