Hi all,
I need to migrate a legacy application from Drools 5.6.0.Final to the
latest stable Drools version.
Current Setup:
- Drools Version: 5.6.0.Final (circa 2013)
- Rule Format: Traditional DRL files (DRL6 syntax)
- API: Using deprecated Knowledge API (KnowledgeBase, KnowledgeBuilder,
StatelessKnowledgeSession)
Questions:
1. What's the latest stable production-ready version of Drools/Apache KIE?
- Is 10.1.0 (July 2025) considered stable for production use?
- Or should I target 9.44.0.Final or 8.44.2.Final instead?
- I'm learning Drools and noticed the versioning changed - 9.x uses
".Final" suffix
but 10.x doesn't. Is this due to the Apache transition? How do I
identify stable
releases in the new versioning scheme?
2. DRL Backward Compatibility:
- Will DRL files written for Drools 5.6.0.Final work unchanged in the
latest version?
- Are there breaking syntax changes between 5.x and 10.x?
- Is there migration documentation or guidance for upgrading DRL files?
- Can I use drools-engine-classic for backward compatibility while
migrating the API layer?
3. Documentation:
- The documentation at https://docs.drools.org/ only shows up to 8.x.
Is there
updated documentation for 9.x and 10.x?
- Where can I find Apache KIE Drools documentation for the latest
versions?
My goal: Upgrade to the latest Java (21+) and Drools version without
rewriting
business rules, by updating only the API integration layer.
Any guidance, documentation links, or real-world migration experiences
would be greatly
appreciated!
--
Regards
Sarthak Kumar Barik
