Code is cheap now.Judgement isn’t.
Free, structured paths to the part of the job a model cannot do for you: system design, AI engineering, databases and low level design. Plain words, real numbers, and diagrams you can break.
Pick a line. Ride it to the end.
Each line is a path with an order to it, so you always know which chapter comes next and how far you have come. Change lines whenever you like. They meet in the places the job does.
System design
34 chapters · about 12 h of readingFrom one overloaded server to designing for a hundred million users. The interview round and the day job.
Board at Scaling from one serverAI engineering
31 chapters · about 4 h of readingLLMs, RAG from basics to agentic and GraphRAG, agents and frameworks, MCP, and evals, for engineers who build on models rather than train them.
Board at How an LLM worksDatabases
16 chapters · about 2 h of readingWhat a database does with your query, and when to reach for Postgres, Redis, MongoDB or DynamoDB.
Board at How a database runs a queryLow level design
23 chapters · about 3 h of readingObjects, SOLID and design patterns, taught alongside TypeScript, so the code survives the next change.
Board at TypeScript for LLDLanguages
44 chapters in 5 paths · about 2 h of readingThe ground floor: JavaScript, React, Node.js, Python and Linux, one idea at a time.
Pick a language
We ask before we tell.
Every chapter stops and asks for your call before it explains anything. Guessing first is what makes the answer stick. Here is one, straight out of the chapter on caching.
Your cache hit ratio slips from 99% to 95%. Traffic has not changed at all. Roughly what happens to the load on your database?
Pick one. Nobody sees your answer.
Diagrams you can break.
Every figure on IndGeek is drawn in code, so you can push on it. Drag the traffic up and watch one server turn into a system, one bottleneck at a time. Each stage links to the chapter that explains it.
The app, the database and the uploads share one box. It is cheap and simple, and one failure takes all of it down.
Chapter: Scaling from one serverOr start from a question you have been asked.
Each one is a full chapter: clarify, estimate, draw, then defend the trade-offs the way you would in the room.
Every design questionFree. Not a free trial. Free.
Every chapter is open to read, with no account and no paywall halfway down the page. What you keep while you read stays in your own browser.
- Highlights with notes
- Select any sentence to mark it, and add a line on why it matters to you.
- Progress on every line
- Mark a chapter read and its station fills in on the map at the top of this page.
- A library of what you saved
- Saved chapters, highlights and notes in one place, ready when you sit down again.
Start with one server.
The first chapter takes one overloaded machine and works out, step by step, what to change and in which order.
Read the first chapter