WildFly is a lightweight, flexible, feature rich, Java EE 7 compliant application server. WildFly 9 even introduced a 27MB Servlet-only distribution. These are very well suited for your enterprise and web applications. WildFly Swarm takes the notch a bit higher. From the announcement: WildFly Swarm is a new sidecar project supporting WildFly 9.x to enable deconstructing the WildFly AS and pasting just enough of it back together with your application to create a self-contained executable jar. Show me the code!