Legacy Modernization with Claude Code
From COBOL, Delphi or old .NET to a modern architecture, with traceable business rules and equivalence tests.
Proof of value in sprints, then a migration factory in waves
Companies with critical legacy systems that are hard to maintain and depend on a few people, and want to migrate without losing business rules.
In legacy systems, business rules live in the code and in the heads of the people who maintain it. Rewriting from scratch loses rules nobody remembers documenting; migrating without tests hides divergences until production.
What we deliver
- A system assessment: size, dependencies, risk and migration order.
- Business-rule extraction with the source passage cited.
- A migration brief approved by your technical and business committee before the transformation starts.
- Code transformed into the target architecture, with equivalence tests.
- Hardening and preparation for operation.
How it works
Assessment
We map the legacy, choose a representative slice for the proof of value and define the target architecture.
Rule extraction
Claude Code reads the code and produces the business rules, each with its origin cited. Specialists on your side validate them.
Approved brief
The committee approves the brief before the transformation, so the new code is born from confirmed rules.
Transformation and tests
The code is transformed and compared with the original behavior through equivalence tests.
Hardening and waves
After the proof of value in sprints, the migration proceeds in waves, like a factory.
- Business rules documented and traceable to the source code.
- A system in the target architecture with tests proving equivalence.
- A wave plan for the rest of the portfolio.
The proof of value measures the migrated slice against criteria agreed in the brief: behavior equivalence in tests, delivery time of the slice and review effort.
- Business and system specialists to validate the extracted rules.
- A committee with authority to approve the brief.
- Access to the source code and test environments.
Frequently asked questions
Do we need to migrate everything at once?
No. We start with a slice in sprints and only then expand in waves.
How do we ensure behavior has not changed?
Through equivalence tests, which compare the new system with the original, and through business rules approved by your committee.
Want to talk about this offering?
We start with a conversation to understand your scope. Each offering has a closed scope and price per phase.