Java is a class-based, object-oriented programming language that is designed to have as few implementation dependencies as possible.
Liferay is an open-source company that provides free documentation and paid professional service to users of its software.
Nginx is a web server that can also be used as a reverse proxy, load balancer, mail proxy and HTTP cache.
Ubuntu is a free and open-source operating system on Linux for the enterprise server, desktop, cloud, and IoT.