The upcoming major release 2.0 will bring significant changes. It will be based on the latest technology stack including Spring Boot 3, Spring 6, and EclipseLink 4. However, Jmix 2.0 will no longer include the Classic UI based on Vaadin 8 because of compatibility issues with the new Jakarta Servlet API and Spring 6.
We understand the importance of Classic UI for many developers, so we’ve adjusted the release schedule to provide longer support for projects with Classic UI.
See details in our blog post: Extended Support for Classic UI. Also, the Jmix Release Versioning page now contains a table with exact information about support timeframes.