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📊 Evaluation & ML Foundations
Core

A/B, Canary and Shadow Testing

Offline evals tell you a change is plausibly better; online testing tells you it actually is. A/B randomizes users between versions to measure real impact with statistical significance. Canary routes a small slice of live traffic to the new version to limit blast radius, and shadow mirrors real traffic to it with no user-facing effect so you can validate safely before anyone is exposed.

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