Write code and run tests in the in-app interactive IDE
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Each concept and coding problem features step-by-step visual walkthroughs
JS Dojo - Technical Interview
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The curriculum is structured so you always know what progress you made
In-browser code editor with instant test feedback
Does it sound familiar?
20 tabs open, zero confidence
You've watched the videos, bookmarked the blogs, and jumped between three different platforms - but each one covers a fraction of what you need. So you keep searching for the next resource instead of actually making progress.
The interview skills no platform teaches
Algo prep has its place - especially at big tech. But DOM manipulation, async patterns, closures, and UI architecture get tested everywhere, and almost no platform covers them. You're left wondering how deep to go on DSA and where to practice the frontend-specific stuff.
Grinding without knowing if you're ready
You've been at it for weeks, but you can't tell if you're 20% ready or 80%. Every session starts with "what should I work on today?" - and half your time goes to deciding instead of doing. The clock is ticking and you can't afford to waste it.
You don't need more resources.
You need the right learning path.
Structured path, not a question bank
Most prep platforms are question banks. JS Dojo is a concept-first learning system - structured like a course, stuffed with visualizations and diagrams, but all grounded in real interview questions.
Learn the why, not just the how
Every concept gets a first-principles explanation before you write a single line of code. You'll build mental models instead of memorizing solutions - so you can handle questions you've never seen before.
Why does this work?
A closure captures the lexical scope at definition time - not at call time. This means...
One clear path, not 500 random problems
Topics are sequenced by dependency - closures before debounce, DOM trees before traversal. No decision fatigue. No wasted time wondering what to study next. Just open the next exercise.
Built for Frontend
Traditional question banks are backend and algorithm-focused. JS Dojo covers what frontend interviews actually test: DOM manipulation, async patterns, UI components, and JavaScript fundamentals.
Generic prep
Reverse a linked list
Find longest palindrome
Knapsack problem
JS Dojo
DOM traversal (BFS/DFS)
Debounce & throttle
Build a data table UI
See it in action
Interactive visualizations are core to every lesson, not an afterthought. Watch the event loop tick, see a closure form, step through recursion call-by-call. Concepts that click visually stick under pressure.
Clear roadmap to ace frontend interviews
From JavaScript fundamentals to advanced UI patterns - structured to build real interview confidence, not just knowledge.
JavaScript Interview Fundamentals
What you'll learn
- Understand Scope, closures and the `this` keyword.
- Solve the most common interview problems: Debounce, IIFEs, memoization, hoisting.
- Unlock the mental models for going through any code listing and explain what happens and when.
How it helps in interviews
- You won't be caught off guard with execution context, scope and hoisting quirks.
- No number of parentheses and expressions inside expressions will scare you anymore.
- You'll explain with confidence the thread of execution and what gets stored in memory at what time.
- You will ace vars, lets and nested loops with timeouts.
- You will explain how Debounce or Memoization work and apply those concepts to multiple scenarios.
Data Structures & Algorithms for Frontend
What you'll learn
- All basic data structures: Arrays, strings, hash maps, stacks, queues, trees.
- The most important algorithms: recursion, binary search, traversing trees and optimizing with hash maps.
- Key interview DSA patterns: sliding windows, counting elements and two pointers.
- How basic algorithms and data structures are used in real Frontend applications.
How it helps in interviews
- Some companies still like the old good DSA interview round - don't blow it up because you didn't study.
- Often tricky UI scenarios can be solved quite easily when knowing how to properly recurse or traverse trees.
- Palindromes, anagrams, reversing strings, removing duplicates are still the backbone of many interviews.
- How to impress an interviewer? Use a data structure or algorithm pattern at the right time when you get the occasion and explain why you did it and how it helps.
- How to antagonize an interviewer? Use these concepts wrongly or at a bad time because you wanted to show off… there is a thin line and you'll learn to balance it with ease.
JavaScript Patterns
What you'll learn
- JS type system deep dive: coercion, equality, typeof quirks.
- Functional programming patterns: compose, curry, pipe, map/reduce from scratch.
- OOP in JS: prototypes, classes, design patterns for Frontend.
- When to use FP vs OOP and how to mix them.
How it helps in interviews
- Build any lodash function or Array.prototype method from scratch instead of reciting memorized code.
- Discuss trade-offs between patterns with confidence.
- Recognize which pattern fits the problem - interviewers value deliberate choices.
- Implement event emitters, middleware pipelines, or DI containers when asked.
Async & Promises
What you'll learn
- Master the event loop: call stack, microtasks, macrotasks, and the rendering pipeline.
- Demystify Promises: chaining, error handling, combinators (all, race, allSettled).
- Async/await patterns and common pitfalls.
- Concurrency control: task runners, chunked processing, and backpressure.
How it helps in interviews
- Predict-the-output questions on event loop ordering will become trivial.
- You'll know how to implement Promise.all or a task runner from scratch.
- Explain clearly why setTimeout(fn, 0) doesn't execute immediately.
- Handle real-world async flows (retries, timeouts, cancellation) with confidence.
- Combine data from multiple async sources in different scenarios.
DOM, UI and Forms
What you'll learn
- BFS and DFS applied to real DOM trees.
- Build querySelector alternatives, DOM serializers, and tree comparison utilities.
- UI components from scratch: tabs, modals, data tables with sorting and pagination.
- Form patterns: validation, multi-step flows, nested state, and accessibility.
How it helps in interviews
- DOM traversal is where DSA meets Frontend - a favorite topic at top companies.
- Live-coding rounds often ask you to build a component from scratch, often in Vanilla JS - you'll handle it under time pressure.
- Form handling demonstrates practical engineering maturity.
- You'll show you can think algorithmically AND ship real UI.
Advanced UI and Apps
What you'll learn
- State machines and undo/redo patterns for complex interactions.
- Real-time data fetching, polling, and dashboard patterns.
- Calculation-heavy UIs: clocks, carousels, grids, timers.
- Full interactive apps: shopping carts, calendars, and games.
How it helps in interviews
- Senior-level rounds test your ability to architect complex frontends.
- Demonstrate you can handle state that goes beyond simple CRUD.
- Show breadth - from math-heavy rendering to real-time data to game loops.
- Solving those in a timely manner will always give you additional points.
Topics and exercises are updated regularly!
Ready to start your prep? Get early access when we launch.
Join the Waitlist →From fundamentals to interview-ready
A simple, repeatable loop that builds real understanding rather than short-term recall.
Learn
Read concept explanations with visual diagrams that build real, durable understanding - not just surface-level familiarity.
What is a Closure?
Practice
Solve exercises in a browser-based code editor with instant test feedback. No setup, no friction - just code.
Master
Build mental models that hold up under interview pressure. Understanding compounds - each topic reinforces the next.
Interview-ready
32 / 41 topics complete
Why JS Dojo?
Not all interview prep is equal. Here's an honest look at how different approaches compare.
| Feature | Question Banks | Video Courses | JS Dojo |
|---|---|---|---|
| Structured learning path | partial | usually | |
| Frontend-specific content | some | varies | |
| Visual explanations | some | some | Core |
| In-browser code editor | |||
| Concept-first approach | some | ||
| Multiple exercise types | some |
Start your interview prep
journey today.
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