About
I'm Hao Hoang. I trained as a mathematician before I trained models, and the habit stuck: I care less about the answer than about why the obvious answer breaks.
AI Interview Prep started in November 2025 as one interview question at a time. It's now 326 issues across 11 series, read by 19,610 engineers. Each issue puts you in an interview, quotes the question, names the answer most candidates give, and walks through the mechanism that makes it wrong. The format is the point. In a senior interview, half right costs you the offer.
On LinkedIn, where about 72.3k engineers follow along, I write about papers and tools the week they ship, plus the occasional joke about the tools we're all drowning in. The long versions live in two books, LLM System Interview and The RAG Interview.
AI Engineer Labs LLC is the company behind the books and the consulting. If you're building something that works in the demo and not in production, that's the part I like.
Email: hao.hoang@aiengineerlabs.us