Compatibility Matrix

QQQ 4.0 compatibility

4.0 release review — September 10, 2026. The documented published candidate is 4.0.0-RC.2. Final 4.0.0 is not yet published. See QQQ 4.0 for scope and acceptance gates.

Component	4.0 train requirement or status
Java	Java 21
Maven	3.8 or later
Core framework	Published candidate 4.0.0-RC.2; final pending
Framework BOM	com.kingsrook.qqq:qqq-bom-pom
Core reactor	18 coordinates: two POMs and 16 JARs
Material Dashboard	Remains 0.40.0
QBit build parent	com.kingsrook:qbit-build-parent:2.0.0 follows publication of final core
Sample / starter / three QBit templates	Included in the first release train; verify the selected source and dependency versions
Production business qBits	Separate compatibility review and release
Frontend replacement / Android / qRun / qStudio	Separate product or development scopes

Dependencies and runtime compatibility

The selected POM and resolved Maven graph define dependency versions. Database and backend operations differ; a common action interface does not establish cross-backend joins, identical query support, or transactions across systems. Test your selected database, identity provider, entry points, and deployment environment.

This page replaces the old unverified 1.x/database/browser support tables. No additional database version, browser range, LTS period, or support SLA is certified here. Use actual release notes and application acceptance evidence.

See QQQ 4.0, Core Modules, and the migration guide.