Legacy System Modernization

Approach

Phase 1 : Technical stabilization

• Automate build and deployment
• Update framework and libraries
• Improve error resilience
• Increase test coverage with scout rule

Security, infrastructure: low + Bugs: many -> Security, infrastructure: higher + Bugs: less

Phase 2: Refine Business domain

• Enrich domain modeling
• Use value objects
• Introduce design by Contract (abstraction of interfaces)
• Resolve Cycles and Dependencies
• Reduce Inheritance

Design: bad -> Design: better（high cohesion, low coupling）

Phase 3: Domain driving transformation

• Exploring and improving the representation of domain
• Modeling of the domain-oriented target architecture
• Matching of target and actual architecture
• Prioritize and execute the refactoring work

Modularity: bad -> Modularity: better

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1. Domain-Driven Transformation: Wie man Legacy-Systemen Struktur zurückgibt - Dr. Carola Lilienthal ↩