AI demos work 90% of the time. Production AI systems need to work 99.9% of the time.
That gap is where the real engineering happens.
Things that matter in production that demos skip:
- Latency budgets. A demo can take 30 seconds. Production workflows need responses in under 5 seconds. This changes your architecture significantly.
- Cost management. A single LLM call in a demo costs pennies. 10,000 calls per day at $0.50/1M tokens adds up fast. You need caching, batching, and model tiering.
- Failure modes. LLMs hallucinate, APIs timeout, models get deprecated. Production systems need graceful degradation for every failure mode.
- Monitoring. You can't fix what you can't see. Every LLM call needs logging, latency tracking, and output quality checks.
- Evolution. Models improve, APIs change, business rules evolve. Your system needs to adapt without rewrites.
The hardest lesson: building a reliable AI system is 20% AI and 80% infrastructure.
What's been your biggest lesson moving AI from prototype to production?