•11 min
A New Model Dropped This Week. Don't Just Bump the String.
Four frontier models shipped in the last 72 hours and your instinct is to change one env var and redeploy. That one-line model swap is the riskiest change you will make this quarter, because tool-calling, output format, cost, and the prompt you tuned all shift at once and nothing throws. Here is how to treat a model upgrade like the dependency change it actually is: pin it behind an adapter, gate it on an eval run against real traffic, and shadow it before you flip.
LLM Engineering
Model Migration