I've been following the Anthropic supply-chain ruling discussion here, and one thing keeps nagging at me as someone learning to build on Next.js while studying LLM app architecture: multi-model redundancy quietly stopped being an optimization and became a compliance requirement for anyone selling to the US government or large enterprises.

A single-model vendor is now officially a supply-chain risk. That makes sense at scale, but what does it actually mean for a small team? Abstracting calls behind one interface sounds easy until models diverge on tool calling, structured outputs, context windows, and latency. And who maintains the eval suite and fallback logic once you support two or three providers?

For those of you running LLM features in production: do you genuinely route across providers, or keep one hot standby? Is an abstraction layer worth it early, or does it just flatten every model to the weakest one? Curious what patterns actually hold up when vendor lock-in becomes a legal problem rather than just a cost one.