Servlet 3.1 allows to have web apps with no web.xml but Maven was giving me errors when trying to package the application.
I had to add this to my pom.xml:
<plugin> <artifactId>maven-war-plugin</artifactId> <version>2.6</version> <configuration> <failOnMissingWebXml>false</failOnMissingWebXml> </configuration> </plugin>