feature.xml defines how features collect plugins and says how things will be installed in a user's Eclipse environment. pom.xml defines what should be built by Tycho. You need both. You also need to ensure that new features are added to the /site/site.xml and the build/aggregate/site/site.xml so that they'll be available on the update site. Without these three touch points, your plugin and its containing feature won't be exposed to users.