Apache Tomcat is a web server written in 100% Pure Java. Apache Tomcat 11.0.x is the current focus of development. It builds on Tomcat 10.1.x and implements the Servlet 6.1, JSP 4.0, EL 6.0, WebSocket 2.2 and Authentication 3.1 specifications. This release is a milestone release and is targeted at Jakarta EE 11.