New track · 100% free

From frontend to full-stack.

You already know JavaScript, HTTP from the client side, state, and async. This track is about everything on the other side of the network line — explained in plain language, one chapter a month, with code you run right here.

Live editors that save your codePlain-language explanations59 practice questions

How to use this track

Read one chapter a month. Read it once early to build the mental model, then again after you've written some code. The practice questions at the end of each chapter aren't optional — if you can't say the answer out loud, the chapter isn't done. Jargon is defined the first time it shows up, because you'll hear these words in real conversations.

  1. 01
    Node.jsmediumWeeks 01–0416 min

    The Runtime

    Node is not just JavaScript on the server. It's a specific machine with specific habits, and once you understand it, the rest of the backend stops feeling like magic.

  2. 02
    DatabaseshardWeeks 05–0818 min

    The Data Layer

    Where senior engineers separate themselves, and where most frontend converts skip ahead. Relational modeling, how Postgres really works, indexes, query plans, transactions, and when to reach for Redis.

  3. 03
    API DesignmediumWeeks 09–1217 min

    The API Surface

    Your APIs are the contract between what you build and everything that uses it. REST done right, the GraphQL/tRPC/gRPC choice, auth from the protocol level, pagination, idempotency, real-time, and background jobs.

  4. 04
    System DesignhardWeeks 13–1620 min

    System Design

    Where senior engineers earn their seniority. Scalability, load balancing, caching, database scaling, consistency models, microservices, events, multi-tenancy, and the canonical designs you should be able to sketch in your sleep.

  5. 05
    DevOpsmediumWeeks 17–2016 min

    The Edge

    The gap between code that works and code that runs in production for years. Containers, where to deploy, CI/CD, observability, SLOs and error budgets, API security, and cost literacy.

  6. 06
    AI EngineeringmediumWeeks 21–2417 min

    The Frontier

    AI features are distributed systems with one extra strangeness: the system itself is non-deterministic. LLM APIs, streaming, RAG, agents, evals, cost engineering, and safety.

Go deeper

Backend deep dives

Real-system case studies (live cricket at 60M viewers, the IRCTC Tatkal rush, a UPI ledger) plus core-topic deep dives on Postgres internals, query plans, auth, idempotency, and more.

All 18 deep dives

Build it

Stop reading, start shipping

The capstone: build one real app — a Snippets service — module by module, applying every chapter as you go, until you have something you can deploy and put on your CV.

All 10 modules