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The 7-Day Interview Prep Cheatsheet

One focused week from rusty to interview-ready.

You have an interview in a week and a job you actually want. Your notes are a mess, the internet is a thousand scattered tabs, and every "top 50 questions" list assumes you already know the answers. You don't need another 600-page book — you need the right things, in the right order, explained like a friend who has sat on both sides of the table.

That's this course. Seven days, one topic a day. Every lesson is built the way strong engineers actually think: a plain-English mental model first, a hand-drawn picture, then real, tested code — always tied straight back to the question an interviewer will ask you, and the follow-ups they'll ask after that.

What's inside

  • Day 1 — Data structures & algorithms: the structures and patterns that decide coding rounds.
  • Day 2 — Core Java: the language questions interviewers keep circling back to.
  • Day 3 — Streams & functional style and Day 4 — Multithreading you can actually defend.
  • Day 5 — Spring Boot, JPA & Hibernate in one sitting.
  • Day 6 — Clean code & design patterns that show up in real rounds.
  • Day 7 — Machine coding: build an LRU cache, a rate limiter, tic-tac-toe, and snake & ladder from scratch.

No fluff, no padding — just the parts that move the needle, with the traps that fail the round called out so you don't walk into them.

Day 1 is free. Read the whole first lesson, see how it feels, and if it clicks, the rest of the week is one small payment away — yours for life, to revisit before every interview you'll ever sit.

What you’ll be able to do

  • Explain every core data structure and pick the right one under pressure.
  • Answer the Java, streams, and concurrency questions interviewers actually ask.
  • Reason about Spring Boot, JPA & Hibernate the way a senior engineer does.
  • Apply SOLID, DRY, YAGNI, KISS and the design patterns that show up in rounds.
  • Walk into a machine-coding round and build LRU, a rate limiter, tic-tac-toe, or snake & ladder from scratch.

Why the course?

The deep-dive articles on this site are free — the course saves you the one thing you’re short on before an interview: time.

One week, one path

No thousand-tab rabbit hole. A day at a time, in the order that actually builds on itself.

Tested, not hand-wavy

Every snippet compiles and runs, and the traps that fail the round are called out so you don’t fall in.

Yours for life

Come back before every interview you’ll ever sit. One payment, no subscription.

The 7-day plan

One topic a day. Day 1 is free — start there.

  1. Day 1 — Data Structures & Algorithms, the essentials Free

    The data structures and algorithm patterns that decide coding rounds — arrays, lists, stacks, queues, maps, sets, heaps, trees, graphs, tries, plus two-pointer, sliding window, binary search, BFS/DFS and recursion-to-DP — with the questions asked most and exercises to practice.

  2. Day 2 — Core Java the interviewer keeps probingPremium

    The core Java that interviews circle back to: OOP done properly, equals and hashCode, the collections framework internals, generics, exceptions, immutability, and a working mental model of JVM memory and garbage collection — with frequently asked questions and exercises.

  3. Day 3 — Java Streams, without the mysteryPremium

    Java streams and functional style explained from first principles: lambdas, functional interfaces, the lazy stream pipeline, collectors, grouping, and Optional — the questions asked most in interviews, plus coding exercises to make it stick.

  4. Day 4 — Multithreading & concurrency you can defendPremium

    Multithreading and concurrency for interviews: threads and executors, synchronized, volatile and atomics, locks, the concurrent collections, and the classic race and producer-consumer problems — with the frequently asked questions and hands-on exercises.

  5. Day 5 — Spring Boot, JPA & Hibernate in one sittingPremium

    Spring Boot, JPA and Hibernate for backend interviews: dependency injection and IoC, building a REST API, entity mapping and relationships, transactions, the N+1 query problem, and lazy-loading and caching pitfalls — with frequently asked questions and exercises.

  6. Day 6 — Clean code & the design patterns that come upPremium

    The clean-code principles and design patterns interviews reward: SOLID, DRY, YAGNI and KISS, then the patterns that actually appear — Strategy, Factory, Builder, Observer, Singleton, Decorator, Adapter and State — each with when-to-use, questions asked, and exercises.

  7. Day 7 — Machine coding: LRU, Rate Limiter, Tic-Tac-Toe, Snake & LadderPremium

    The machine-coding and low-level design round, solved live: build an LRU cache, a rate limiter, tic-tac-toe, and snake & ladder from scratch, plus a repeatable way to approach any machine-coding problem under time pressure — with frequently asked follow-ups.