The first step to begin contributing is to sign the Eclipse Foundation Committer and Contributor Agreement (ECA): https://www.eclipse.org/legal/committer_process/re-sign/. The ECA must be signed by anyone who wants to contribute to an Eclipse open source software or specification project. This allows one to have the ability to accept a contributor's pull requests.
The Eclipse ICA (Eclipse Individual Committer Agreement) can be signed by those who do not work for the Eclipse Foundation Member Company when they become a committer.
** Note: Be sure that your employer is okay with you signing the agreement. In many cases it is a win-win for all...as your contributions will benefit the community, including your employer.
Sign up for the mailing lists and get involved. Certainly sign up for the Jakarta Platform Developer mailing list, as many of the details for moving the platform forward are being discussed here.
Look through the list of projects that are part of Jakarta EE and sign up for the individual mailing lists for those projects which you are interested in helping out: https://projects.eclipse.org/projects/ee4j
A few of the tasks for the delivery of Jakarta EE 9 include the following:
* Take control of the CI/CD pipeline for release.
* Coordinate release across all the projects.
* Make the actual changes to the API, docs and TCK.
* Make the implementation changes on at least one server - probably Eclipse GlassFish.
Hopefully this will be of use to hose who are interested in getting started.