Zero-downtime migration
Zero-downtime migration approach
The method is what makes a zero-downtime migration possible. The same three ideas apply on every engagement, whatever system is in front of us, and they carry over to our AI work too.
Strangler-fig, not big-bang
A big-bang cutover bets the whole business on one weekend going perfectly. A strangler-fig approach routes traffic to the new system incrementally, one slice at a time, so a failure is contained to that slice instead of the entire system. It takes longer than a big-bang plan on paper — it's dramatically faster in practice, because it doesn't produce a multi-week outage when something goes wrong.
Dual-write verification
Before we trust the new system with real traffic, it runs in parallel with the old one: writes go to both, and we diff the results continuously until they agree. That's what "verified" means here — not a manual spot check before cutover, but a running proof that the new system produces the same answers as the old one under real production load.
Rollback-ready cutover
Cutover day follows a runbook, and the runbook always includes the way back. If a rollback path isn't tested, it doesn't exist — so we rehearse it before go-live, the same way we rehearse the cutover itself. The goal is for cutover day to be boring.
The same discipline, applied to AI
AI-assisted engineering and AI adoption get the same treatment. Code written by an agent goes through review and tests like any other change. Pilots are scoped small enough to stop. Agents get only the permissions the task needs. Every recommendation comes with its trade-offs written down, including when the honest answer is that a tool isn't ready for your use case yet.