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Product Engineering · June 30, 2026

Modernizing legacy SaaS without a big-bang rewrite

Strangle patterns, risk budgets, and when a Squad beats a greenfield fantasy.

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Big-bang rewrites fail because they pause learning. Prefer a strangler: extract one high-churn surface, put it behind a clear API, and ship weekly. ## Operating rules - Freeze scope on the legacy core except for critical fixes - Instrument before you migrate - Keep one tech lead accountable for both old and new paths - Use AI for tests and scaffolding — humans own cutover Agents can accelerate migration scripts; they cannot own customer trust. --- **Ready to put this into practice?** [Send a brief](/contact) — we’ll map Starter, Squad, ODC, or an Agent product sprint to your next 90 days.

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