Building blocks for durable business systems.
Jexxa Projects collects and shares methods for developing durable software systems, such as Domain-Driven Design and Hexagonal Architecture. We provide open-source libraries, frameworks, and tutorials that support development teams in the daily challenges of long-lived business applications.
Our guiding idea: legacy systems stay as they are, but everything that integrates them is built on a modern language level. Modern, domain-driven applications and the bridges to legacy systems belong together, so we develop them together.
| Project | Role | Status |
|---|---|---|
| Jexxa | Framework for DDD and Ports & Adapters applications (Java) | In production for 6 years |
| JLegMed | Semantic bridging of legacy and modern systems (Java) | In production for 3 year |
| DigiSpine | Digital backbone connecting business domains via domain events | In production for 1 year |
| CLegMed | C++23 counterpart to JLegMed | In development |
| JexxaAdapters | Reusable infrastructure adapters and integration patterns | Supporting library |
| ESPAdapters | Event streaming (Apache Kafka) adapters | Supporting library |
| Addend | Domain annotations for DDD | Supporting library |
| JexxaTutorials | Tutorials and sample projects | Documentation |
| JexxaArchetypes | Maven archetypes for a quick start | Tooling |
- Building a new, long-lived business application: Jexxa, then the tutorials
- Connecting a legacy system: JLegMed (Java) or CLegMed (C++23, in development)
- Networking several business domains via domain events: DigiSpine
flowchart LR
LEGACY["Legacy systems"] --> BRIDGE["JLegMed / CLegMed<br/>(bridges)"]
BRIDGE --> SPINE["DigiSpine<br/>(domain events)"]
SPINE <--> APPS["Jexxa applications<br/>(domain-driven business logic)"]
The ecosystem runs in the manufacturing IT of a steel producer: Jexxa for six years in a blast furnace MIS and a steelworks MES, JLegMed and DigiSpine for one year in the rolling mill for real-time analytics, including closed-loop processing of production plans for production control.
All projects are and will remain open source under permissive licenses and are built with Free/Libre Open Source Software. Optional consulting and implementation services are available from MCR Industrial Intelligence.
Interested in durable systems and team development? Have questions, challenges, or success stories? You are welcome to join this group or start a discussion.