https://aiengineering.guide/ New lessons, notes, and case files from the zero-to-shipping AI engineering roadmap. en https://aiengineering.guide/lesson/what-is-an-llm https://aiengineering.guide/lesson/what-is-an-llm The mental model that will carry you through the rest of the roadmap. Not the history, not the maths — the mechanism, in the shape you'll actually reason about when things go wrong. lesson Tue, 08 Sep 2026 00:00:00 GMT https://aiengineering.guide/lesson/llm-gateway https://aiengineering.guide/lesson/llm-gateway One door in front of every model call, where limits, retries, and fallbacks live once. Build the limiter from scratch, then see what a real gateway adds. lesson Sun, 02 Aug 2026 00:00:00 GMT https://aiengineering.guide/notes/streaming-is-not-free https://aiengineering.guide/notes/streaming-is-not-free Token streaming looks like a latency win, but it moves work into your error handling and your client. Here's what it actually costs. note Sun, 02 Aug 2026 00:00:00 GMT https://aiengineering.guide/cases/eval-pipeline-that-lied https://aiengineering.guide/cases/eval-pipeline-that-lied A team shipped model changes against a green eval suite for a month while quality quietly dropped. Here's the decomposition — and the wrong turn that hid it. case Sun, 02 Aug 2026 00:00:00 GMT