Foundations
Make the machine do what you meant.
Conditionals
Branching: if, else, and the truthiness that trips everyone up.
Loops
for, while, for…of — and knowing which one the job wants.
Arrays
Indexing, iterating, mutating — and why mutation bites.
Functions
Arguments, returns, and the call stack underneath them.
Boss: FizzBuzz & Friends
Prove the basics under pressure: a live interview and a real challenge.
Thinking in Code
Stop guessing. Start reasoning about cost.
Recursion
A function that calls itself — and the base case that saves it.
Sorting
Bubble sort by hand, so every sort after it makes sense.
Big-O
How your solution behaves when the input stops being small.
Boss: Problem Solver
A hard challenge and a medium interview. No hints, no mercy.
JavaScript, Properly
The parts that separate a coder from a JavaScript developer.
Scope & Hoisting
Why your variable is undefined before the line that sets it.
Closures
The single most-asked interview concept in JavaScript.
Value vs Reference
Why copying an object is nothing like copying a number.
Objects & Classes
Prototypes, `this`, and the class syntax sitting on top of them.
Boss: JavaScript Interview
Closures, this, prototypes — spoken, out loud, under pressure.
Async JavaScript
One thread, and still nothing blocks. Learn how.
The Event Loop
Call stack, task queue, microtasks — the order things actually run.
Promises & async/await
What await really pauses, and what it very much does not.
The Web
The document, the styles, and the interview questions about both.
HTML & Semantics
Structure, forms, accessibility — the part everyone skips and regrets.
CSS & Layout
Specificity, flexbox, grid, responsive design.
React & Next.js
Components, state, and rendering on somebody else’s machine.
React Core
Hooks, state, effects, and why your component rendered twice.
Next.js
App Router, server components, data fetching, caching.
Boss: Frontend Engineer
An expert React grilling. This is the real interview.
Backend
The server, the database, and who is allowed to talk to them.
Node & Express
Runtime, routing, middleware, error handling, REST design.
MongoDB
Documents, indexes, aggregation, schema design.
Auth & JWT
Tokens, sessions, signing, refresh flows — and how they get broken.
Job Ready
The gauntlet. Everything, in English, under pressure.
Talk to Humans
Networking, and asking for what you are worth.
Boss: The Gauntlet
A hard one-shot challenge and an expert interview. Then you are done.