The Jakarta EE Platform project produces the Jakarta EE platform specification, which is an umbrella specification that aggregates all other Jakarta EE specifications.

Jakartaee-tck

Home of 'jbatch', a compatible implementation of the Jakarta Batch specification (and the former Reference Implementation for the JSR 352, Batch Applications for the Java Platform specification).

Jakarta EE 10 MVC sample

Jakarta Authentication Implementation

Jakarta-EE-8-Recipes. Published by [Packt]

Source Code for 'The Definitive Guide to Jakarta EE Security' by Arjan Tijms, Werner Keil, and Thodoris Bais

Source Code for 'Enterprise Social for the Java Platform' by Werner Keil