Sonar for Linux is an open platform to manage code quality. As such, it covers the seven axes of code quality. Covering new languages, adding rules engines, computing advanced metrics can be done through a powerful extension mechanism. More than 30 plugins are already available. Sonar has got a very efficient way of navigating, a balance between high-level view, dashboard, TimeMachine and defect hunting tools. This enables to quickly uncover projects and / or components that are in Technical Debt to establish action plans. Sonar is a web-based application. Rules, alerts, thresholds, exclusions, and settings can be configured online. By leveraging its database, Sonar not only allows to combine metrics altogether but also to mix them with historical measures.