In building software-as-a-service applications, a flexible development environment is key when it comes to shipping early and often. For this reason, schema-flexible data stores are becoming more and more popular: These systems can store heterogeneous structured data, allowing for new releases to be pushed frequently without requiring involved schema migrations prior to the release. However, the current application code must continue to work with any legacy data. To let legacy data “catch up” with the latest release of the application code, developers commonly employ object mapper libraries with life-cycle annotations. Yet, when used without caution, this approach can lead to runtime errors and data loss. We demonstrate an IDE plugin that detects evolutionary changes to the application code that are incompatible with legacy data. Our ControVol plugin warns developers already at development time, and even suggests automatic fixes to resolve potential issues. Thus, ControVol ensures that legacy data can lazily catch up with the latest software release. A demo video is available at http://tinyurl.com/mh7a743.