The central concern of the CLARITY project is to support open innovation for Model-Based Systems Engineering by structuring an ecosystem of major actors of the domain and providing an open-source environment, Capella, and its underlying methodology, Arcadia. In this experience report, we relate the Capella story from the initial development by Thales down to the open-sourcing strategy. The rationale for adopting the open-source model is detailed with commercial, competitive and strategic arguments. The global roadmap of Capella is then presented. One year after the start of the CLARITY project, a first feedback is shared.