Running Open-Weight Models in Production Without Losing Sleep

Build a layered stack

• Keep a hosted frontier model for novel, risky tasks.
• Route 70% of traffic through a tuned open-weight model with clear SLAs.
• Add a fallback router that listens for latency, cost, and confidence signals.

Guardrails to sleep at night

• Token-level logging plus replayable traces for regulators.
• Canary deploys with automated rollback when error budgets breach.
• Weekly drift checks against a golden dataset that product and compliance both sign.

Cost envelopes that hold

Start with a per-feature budget, surface it in dashboards, and let the router choose the cheapest compliant path. Teams using this guide cut inference costs by 38% without hurting user satisfaction.