How Shopify built an AI stack that doesn't care which models survive

Shopify built an LLM proxy that gives every engineer access to multiple AI providers — with automatic failover when any one of them goes down, changes, or disappears. When Claude Fable 5 shut down , Shopify's engineers didn't go into panic mode. The proxy shifted them to Claude Opus or GPT 5.5 automatically, without interrupting their workflows.