In my previous article , I explored operational conformance: how to evaluate whether observed evidence satisfies an operational specification.

That gives us a useful point-in-time question:

Does the system satisfy the specification right now?

But production systems don't stay still.

Traffic changes. Dependencies degrade. Certificates expire. Configuration is modified. Feature flags move. Data grows. People make manual changes. Agents take actions. Infrastructure is replaced. And so on.

A system can be conformant immediately after a deployment and stop being conformant hours or days later.

That's the problem I want to explore here.

Operational drift is the divergence between the operational specification and the state we continue to observe over time.

This is broader than configuration drift.…