Role guide · Free PDF
AI Engineer
LLM fundamentals, RAG, agents, evals and the questions about your own projects.
Interview prep for AI jobs
AI engineer, ML engineer, data scientist, MLOps and AI product manager, plus system design for agents, RAG, ML systems and databases. The questions you’ll get, the answers to give, and the follow-up that comes next.
New to AI? Start here
The AI ideas everyone should know, in plain language: how ChatGPT works, why it makes things up, and what AI can and can’t do. No math, no jargon, and a one-sentence version of every idea you can repeat in a meeting or an interview.
Guides by role
Each role gets its own interview loop. Each guide follows it, round by round.
Role guide · Free PDF
LLM fundamentals, RAG, agents, evals and the questions about your own projects.
Role guide · Free PDF
ML fundamentals, model training and evaluation, feature pipelines and the ML system design round.
Role guide · Free PDF
How LLMs work, prompting, fine-tuning vs RAG, structured outputs, cost and latency.
Role guide · Free PDF
Deploying and serving models, pipelines, monitoring, drift and rollbacks.
Role guide · Free PDF
Statistics, experiments, SQL, modeling and the product case questions.
Role guide · Free PDF
When to use AI, how to measure it, risk and trust, and the product sense round.
System design
The design round is open-ended and hard to practice alone. Work through the systems you’re likely to be asked about.
System design · Free PDF
A framework for the design round and worked cases: support bot, document search, coding agent and more.
System design · Free PDF
Agent loops, tools, state and memory, permissions, and how agents fail in production.
System design · Free PDF
Ingestion, chunking, retrieval, reranking, grounding and evaluating answers.
System design · Free PDF
Recommendations, ranking, search and fraud detection, from data to serving.
System design · Free PDF
Serving models at scale: batching, caching, GPUs, streaming and cost per request.
System design · Free PDF
Choosing a database, indexing, replication, sharding, consistency and vector stores.
System design · Free PDF
Batch and streaming, queues, backfills, data quality and feature stores.
Answer it out loud first, then open the model answer.
System design for RAG and LLM apps
When would you not use RAG?
When the knowledge isn't unstructured text that people search by meaning. If the corpus is small and stable, I paste it into the prompt: no retrieval step means no retrieval misses. If the question is structured, like "orders over $500 last month," that's a SQL query behind a tool, because embeddings are fuzzy and the question is exact. If the data changes per request, like an account balance or the user's current plan, I call the live API instead of indexing a snapshot that goes stale. And if it's general, stable knowledge the model already handles well, retrieval only adds latency.
My two sorting questions are: is it structured, and does it change per request? A yes to either usually means a tool, not an index. RAG's lane is semi-stable documents people search by meaning, like a handbook or a help center.
Built for the weeks before the interview, not a semester of reading.
Grouped the way the interview loop runs: fundamentals, building, production, your projects.
About a minute each: the answer first, one example, one tradeoff.
The one thing each question tests, so you know what a strong answer has to show.
The question that comes next, so it doesn’t catch you off guard.
The weak answer interviewers hear most, and why it costs you.
Print it or read it on your phone on the way to the interview.
FAQs
Interview prep for AI jobs: one guide per role (AI engineer, ML engineer, generative AI engineer, MLOps, data scientist, AI product manager), a system design guide for each kind of system you may be asked to design, and AI Basics for anyone new to AI.
The questions that come up for that role, each with a model answer you can say in about a minute, what the interviewer is checking, the follow-up they will ask, and the mistake to avoid. As a PDF you can print or read on your phone.
The PDFs are free: leave your email and we send each one when it is ready. 155 questions are already on the site, with sample answers.
A chatbot answers whatever you ask. A guide decides what to study: the questions for your role, answers sized for a spoken reply, and the follow-up you will get next.
Pick the guides you want. We’ll email each one the day it’s ready.