Strangler-fig cutover of a 15-year monolith

Anti-corruption layers, traffic shaping, and feature flags so the old system could die without a big-bang weekend.

2022 — 2024

3 days → same-day

Deploy cycle

Zero-downtime

Cutover

The situation

A 15-year-old monolith was still the system of record. Replacing it in place would have meant a freeze and a leap. The safer path was to grow the new system around the old one and peel traffic off when each seam was ready.

The work

I defined anti-corruption layers, traffic-shaping policies, and a feature-flag framework so cutover could happen without downtime.
I established CI/CD with automated quality gates and took deploy cycle time from three days to same-day.
I led the DevOps maturity work: Terraform, secrets management, and drift detection.

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