Frontend Developer Interview Preparation Guide - Junior Level (1-2 Years Experience)
This guide is based on general FAANG interview practices and may not reflect specific company procedures.
The interview process for a Junior Frontend Developer typically consists of 6 rounds spanning 3-4 weeks. You will progress through recruiter screening, multiple technical evaluations focusing on JavaScript fundamentals, HTML/CSS proficiency, DOM manipulation, UI component building, framework expertise (React/Vue/Angular), and behavioral assessment aligned with company values. Each round builds on your demonstrated skills and cultural fit. For Junior level roles, the emphasis is on strong fundamentals, ability to work independently with guidance, and demonstrated capacity to write clean, maintainable code that prioritizes user experience.
Interview Rounds
Recruiter Screening Call
What to Expect
This initial conversation with a recruiter is focused on understanding your background, motivation, and cultural fit. The recruiter will discuss your resume, experience, career goals, and why you're interested in the role and company. They'll outline the interview process timeline, logistics, and answer your initial questions. This is your opportunity to research the company thoroughly, understand the Frontend Developer role's specific responsibilities, and present yourself professionally and authentically. At Junior level, recruiters are assessing your communication skills, enthusiasm for learning, ability to explain your experiences clearly, and whether you'd be a good fit for the team culture.
Tips & Advice
Prepare a 30-60 second elevator pitch about who you are, your 1-2 years of Frontend experience, key projects you've worked on, and what excites you about this specific role. Research the company's products, culture, recent engineering blog posts, and tech stack beforehand—be able to speak intelligently about why this company appeals to you specifically. Have 2-3 genuine, thoughtful questions ready about the role, team, or company culture (examples: What challenges are you currently solving as a Frontend team? How does the team approach learning new technologies? What does success look like for this role in the first 6 months?). Avoid generic questions that could apply to any company. Be clear about your schedule and availability for subsequent rounds. When discussing your experience, mention relevant projects that showcase growth, problem-solving, or collaboration. For Junior level, emphasize your enthusiasm for learning and specific examples of how you've grown in your time in the field.
Focus Topics
Growth Mindset & Coachability
Demonstrating genuine openness to feedback, curiosity about learning new technologies and frameworks, and ability to take challenges constructively. Sharing examples of areas where you've improved or technologies you've learned recently.
Practice Interview
Study Questions
Company & Role Research
Demonstrating knowledge about the company's products, mission, culture, tech stack, and how the Frontend Developer role contributes to business goals and user experience. Understanding the specific challenges the team faces.
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Study Questions
Experience Storytelling with Concrete Examples
Ability to narrate your technical projects and experiences using the STAR method (Situation, Task, Action, Result). Highlight learning experiences, challenges overcome, and impact. Include specific examples of frontend work like components built, performance improvements, or accessibility features implemented.
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Study Questions
Professional Communication & Presentation
Ability to articulate your background, experience, and motivation clearly and concisely. This includes explaining your technical projects in simple terms, discussing your career trajectory, and expressing genuine interest in the role. Speaking confidently about your work without overstating experience.
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Study Questions
Technical Phone Screen
What to Expect
This 45-60 minute technical assessment tests your foundational knowledge of JavaScript, HTML, CSS, and basic problem-solving ability. You'll solve 1-2 coding problems using an online code editor (like CoderPad, HackerRank, or Leetcode), answer technical questions about frontend concepts, or explain how the browser works. Problems typically involve string/array manipulation, basic DOM concepts, or implementing simple utility functions. At Junior level, interviewers assess whether you have solid fundamentals, can think through problems systematically, communicate your approach, and write reasonably clean code. They're not expecting senior-level optimizations but looking for your problem-solving methodology and ability to work through challenges.
Tips & Advice
Start each problem by asking clarifying questions: What are the inputs? What should the function return? Are there constraints (like memory or time limitations)? Don't assume you understand the problem completely. Write pseudocode or outline your approach verbally before coding—this helps the interviewer follow your thinking. Test your code with multiple examples, including edge cases (null, undefined, empty arrays, negative numbers). If you get stuck, don't panic—think out loud, walk through the problem step by step, or ask for hints rather than sitting silently. At Junior level, communication and approach matter significantly more than perfect, optimized code. Use descriptive variable and function names that make intent clear. If you finish early, discuss potential optimizations, trade-offs, or alternative approaches. Have a comfortable coding environment set up beforehand. Practice similar problems on LeetCode or CodeSignal at Easy-to-Medium difficulty before the interview.
Focus Topics
HTML Semantics & Accessibility Fundamentals
Understanding semantic HTML elements (header, nav, main, article, section, footer, aside) and their appropriate usage. Knowledge of basic accessibility principles including alt text for images, ARIA labels for interactive elements, keyboard navigation considerations, and proper heading hierarchy. Understanding why semantic HTML matters beyond just structure (SEO, accessibility, maintainability).
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Study Questions
Problem-Solving Approach & Code Clarity
Ability to break down problems into smaller, manageable steps. Writing code with clear variable and function names that make intent obvious. Using comments where logic is non-obvious. Communicating your thought process throughout the solution. Acknowledging when you don't know something and asking for clarification.
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Study Questions
CSS Box Model & Positioning
Understanding the CSS box model (content, padding, border, margin), how it affects element sizing, margin collapsing, and overflow behavior. Understanding the difference between border-box and content-box sizing. Knowledge of positioning properties (static, relative, absolute, fixed) and how they affect layout. Understanding stacking context.
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Study Questions
Asynchronous JavaScript - Promises & Async/Await
Understanding how Promises work, state transitions (pending → fulfilled/rejected), .then() chaining, error handling with .catch(), Promise.all() basics, and async/await syntax as syntactic sugar over Promises. Understanding the event loop at a basic level. At Junior level, focus on understanding the flow of async operations and avoiding common pitfalls like unhandled rejections or improper error handling.
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Study Questions
JavaScript Fundamentals - Array & String Methods
Deep working knowledge of commonly used array methods (map, filter, reduce, find, includes, slice, splice, concat, reverse) and string methods (split, join, substring, slice, indexOf, includes, replace, trim). Understanding what each method does, its parameters, return value, and being able to chain methods effectively. At Junior level, focus on knowing when to use each method and being able to use them correctly in combination.
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Study Questions
JavaScript Closures & Scope Chain
Understanding how closures work, lexical scoping, the scope chain, and how variables are captured by inner functions. Ability to explain why closures exist, recognize closure patterns in code, and use them appropriately. At Junior level, focus on reading and explaining existing closures correctly rather than building complex closure-based systems.
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Study Questions
JavaScript - this Keyword & Context Binding
Understanding how 'this' binding works in different contexts: global scope, object methods, arrow functions vs regular functions, and constructors. Ability to explain and predict what 'this' refers to in various scenarios. At Junior level, focus on recognizing common 'this' issues and understanding why certain patterns work the way they do.
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Study Questions
Frontend Coding Interview - JavaScript Utilities & DOM APIs
What to Expect
In this 60-minute technical round, you'll implement 1-2 JavaScript utility functions or DOM APIs from scratch, demonstrating deep understanding of JavaScript internals. Common examples include implementing Array.prototype.map/filter/reduce from scratch, Array.prototype.some/every, document.getElementById or document.getElementsByClassName, debounce/throttle functions, Promise or Promise.all polyfills, or simple DOM traversal utilities. You'll use an online editor or screenshare your local environment. This round tests your understanding of JavaScript's functional programming patterns, ability to build reusable code, attention to edge cases, and code quality. For Junior level, the focus is on correct implementation of core functionality with reasonable handling of edge cases, not necessarily optimal performance or handling every edge case the actual browser API supports.
Tips & Advice
Before writing any code, discuss your approach: What are the function signature and inputs? What should it return? What edge cases exist (null, undefined, empty arrays, type mismatches)? Ask clarifying questions if requirements are ambiguous. Start with a basic working solution that you can explain clearly, then discuss optimizations if time permits. Write clean code with meaningful names. Test your implementation with multiple cases including edge cases. Don't aim for production-ready perfection—at Junior level, showing your thinking process and arriving at a working solution is what matters most. If you get stuck, think out loud rather than sitting in silence. Ask for hints or clarification when needed. Explain why you chose certain patterns or approaches. Use consistent code formatting and add comments for non-obvious logic.
Focus Topics
DOM API Methods & DOM Traversal
Understanding how to implement basic DOM query methods like getElementById, getElementsByClassName, or querySelector-like functionality. Understanding DOM tree structure, how to traverse it (parent, children, siblings), and what properties and methods elements have (innerHTML, textContent, classList, getAttribute, etc.). At Junior level, focus on basic functionality and understanding how these APIs work under the hood.
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Study Questions
Debounce & Throttle Functions
Understanding the difference between debouncing and throttling: debounce delays execution until after a period of inactivity; throttle ensures a function runs at most once per time interval. Implementing both functions correctly. Recognizing their use cases. At Junior level, focus on core implementation of both patterns and clearly explaining their differences.
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Study Questions
Promise Implementation & Async Flow
Understanding Promise structure, state machine (pending → fulfilled or rejected), how resolve and reject work, .then() chaining, error handling with .catch(), and basic Promise.all() functionality. Understanding microtask queue at a basic level. At Junior level, focus on core Promise concepts and correct implementation rather than spec-compliant edge cases.
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Study Questions
Edge Case Handling & Defensive Programming
Thinking about edge cases (null, undefined, empty inputs, negative numbers, large datasets, type mismatches), anticipating what could break your code, and writing defensive code that handles these gracefully. Testing implementations with various inputs to ensure robustness.
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Study Questions
Array Methods Implementation (map, filter, reduce, some, every)
Ability to implement common array transformation methods from scratch using basic JavaScript. Understanding what each method does, its signature (inputs, return value), how it iterates through elements, and handling edge cases like empty arrays or null values. Recognizing that these methods accept a callback function and return new arrays or values based on the callback's behavior.
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Study Questions
JavaScript Callbacks & Higher-Order Functions
Understanding functions as first-class objects, passing functions as arguments (callbacks), returning functions from functions, and the concept of higher-order functions. Recognizing how callbacks are used to customize behavior. At Junior level, focus on understanding and using these patterns correctly in practical contexts.
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Study Questions
Frontend UI Component Building Interview
What to Expect
This 60-minute technical round focuses on building an interactive UI component using HTML, CSS, and JavaScript (vanilla or a framework). Common components include autocomplete/dropdown with filtering, image carousel with navigation, accordion with expand/collapse, form with client-side validation and error display, star rating widget, or a simple todo list app. You'll implement the component in a live environment (CodePen, CodeSandbox, or local environment with screenshare). This round tests your ability to translate requirements into working, interactive UI; handle user interactions effectively; style components responsively; and write clean, maintainable code with good separation of concerns. For Junior level, the focus is on core functionality, basic responsiveness, and clean code structure rather than pixel-perfect polish or advanced animations.
Tips & Advice
Start by asking clarifying questions: What should the component do? What interactions should it support (clicking, typing, keyboard navigation)? What should happen on edge cases (empty state, errors, loading)? Sketch or verbally describe your approach before coding. Structure your implementation: build HTML structure first with semantic, meaningful markup; then style with CSS for layout and appearance; finally add JavaScript for interactivity. Use descriptive class names and IDs. Ensure your component has basic keyboard accessibility if applicable and works reasonably on mobile devices (responsive). Test different user scenarios (filling the form, clicking buttons, edge cases). Don't aim for pixel-perfect design—focus on functional correctness and code quality. If you finish early, discuss potential improvements: better error handling, animations, accessibility features, or performance. For Junior level, clean, understandable code with working functionality is far more valuable than polished design with complex code.
Focus Topics
User Experience & Interactive Feedback
Creating intuitive interactions that feel responsive and polished: providing visual feedback for user actions (hover states, active states, disabled states, loading indicators), handling edge cases gracefully, considering keyboard navigation, and thinking about accessibility. Making components feel professional and usable.
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Study Questions
Code Organization, Clarity & Maintainability
Structuring code logically with clear separation of concerns (HTML, CSS, JavaScript). Using meaningful variable and function names. Avoiding code duplication through DRY principles. Writing code that could be easily understood and maintained by other developers. Adding helpful comments for complex logic.
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Form Handling, Input Validation & Error Feedback
Building forms with proper HTML structure, handling form submissions, validating user input on the client side (required fields, email format, length requirements), providing clear, helpful feedback to users about validation errors, and handling edge cases like empty submissions or invalid data. Understanding form elements and their properties.
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Study Questions
Component State Management & Data Flow
Managing component state effectively: identifying what data the component needs, structuring state logically, updating state based on user interactions, and ensuring the UI reflects current state accurately. Understanding one-way data flow. Avoiding common state management issues like stale state or inconsistent state. At Junior level, focus on managing simple, local component state clearly rather than complex global state patterns.
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CSS Styling & Responsive Design Implementation
Styling components with CSS using modern techniques (Flexbox, CSS Grid for layout). Implementing responsive design with media queries to work across device sizes (mobile, tablet, desktop). Understanding CSS specificity and how to organize styles effectively. Making components look professional and functional at various breakpoints. At Junior level, focus on making components look clean and work on different screen sizes rather than advanced animations or micro-interactions.
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HTML Structure & Semantic Markup for Components
Building proper, semantic HTML structure for components that clearly represents the component's purpose and hierarchy. Using semantic elements (button, form, input, label, fieldset, etc.) appropriately. Understanding form elements, input types, and accessibility attributes like aria-labels, aria-required, aria-disabled. Writing HTML that is readable and maintainable.
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Study Questions
JavaScript Event Handling & DOM Interaction
Adding interactivity with JavaScript: attaching event listeners (click, input, change, submit, keydown), manipulating the DOM based on user actions (adding/removing/updating elements), managing state within the component, and updating the UI when state changes. Understanding event bubbling and event delegation. At Junior level, vanilla JavaScript event handling is typically more valued than framework-specific patterns to demonstrate core understanding.
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Study Questions
Framework Specialization Interview (React/Vue/Angular)
What to Expect
In this 45-60 minute technical round, you'll be assessed on your proficiency with the company's primary frontend framework (commonly React at FAANG companies, though could be Vue, Angular, or Svelte). This round might involve building a simple app component with dynamic data, refactoring code for better performance or cleaner patterns, answering framework-specific technical questions, or discussing architectural decisions. You'll demonstrate understanding of component architecture, state management patterns, lifecycle, hooks (for React), performance optimization, and framework best practices. For Junior level at FAANG companies, React is standard; focus on demonstrating solid understanding of functional components with hooks, proper useEffect usage, and component composition patterns.
Tips & Advice
Ensure you're deeply comfortable with your target framework before the interview—it should be second nature. For React specifically, practice extensively with functional components and hooks as they're now the standard (class components are rarely used). Understand React's rendering model, when components re-render, how to avoid unnecessary re-renders, and when different hooks are appropriate. Write components with single, clear responsibilities and structure them for reusability. Ask clarifying questions about component requirements and edge cases. If refactoring code, explain your improvements clearly and discuss trade-offs. Test your code mentally or actually to ensure it works correctly. At Junior level, showing solid fundamentals and understanding best practices matters more than demonstrating knowledge of advanced patterns. Be ready to discuss why you chose certain approaches and trade-offs between different solutions.
Focus Topics
React Patterns, Best Practices & Code Organization
Understanding common React patterns like conditional rendering, list rendering with keys, composition over inheritance, custom hooks basics, and React best practices for component naming, file organization, and code style. Understanding why certain patterns work and when to apply them.
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Study Questions
React Performance Optimization Basics
Understanding React's rendering optimization techniques: React.memo for component memoization, useMemo for expensive computations, useCallback for callback memoization, and understanding when components unnecessarily re-render. Understanding that not all optimization is beneficial and premature optimization is wasteful. At Junior level, focus on understanding these concepts, recognizing performance issues, and knowing when these techniques are helpful rather than premature optimization.
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React Event Handling & Forms
Handling events in React (onClick, onChange, onSubmit, onFocus, etc.), understanding React's synthetic event system, creating controlled form components, managing form state, form submission handling, and validation. Understanding the difference between controlled and uncontrolled components and when each is appropriate.
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Study Questions
React Component Composition & Props
Understanding how to build reusable, composable components by passing data and callbacks through props. Understanding prop drilling and its limitations. Implementing controlled vs uncontrolled components. Handling prop types and validation. Building component hierarchies that are logical and maintainable. Recognizing when to split components and how to structure components for reusability.
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React Functional Components & Hooks
Deep understanding of React's functional component model and hooks. Mastering useState for state management, useEffect for side effects and lifecycle, dependency arrays, cleanup functions, and avoiding common hooks pitfalls (dependencies, infinite loops, stale closures). Knowing when and how to use other hooks like useContext, useReducer basics. At Junior level, focus on using hooks correctly for common patterns: managing state, fetching data, handling events, and managing side effects.
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React State Management & Rendering Cycles
Understanding React's state model deeply: how state updates work, batching of updates, rendering cycles, why components re-render, and how to optimize rendering. Managing component state with useState, understanding when state triggers re-renders. Recognizing and preventing unnecessary re-renders through proper dependency management.
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Study Questions
Behavioral & Cultural Fit Interview
What to Expect
This 45-60 minute round assesses your cultural alignment with the company, ability to work effectively in teams, communication skills, how you handle challenges and failures, and your growth mindset. You'll be asked behavioral questions about your experiences working with others, overcoming obstacles, learning from mistakes, handling disagreements, and how your values align with company culture. The interviewer will also assess your curiosity about the role, ability to ask thoughtful questions, and genuine interest in the team and company. For Junior level, the focus is on coachability, collaboration skills, learning ability, and cultural fit rather than extensive leadership experience or individual heroics.
Tips & Advice
Use the STAR method (Situation, Task, Action, Result) for all behavioral questions—structure your answers clearly. Prepare 4-6 concrete stories from your work or projects that demonstrate key competencies: problem-solving, collaboration, learning from feedback, taking initiative, overcoming challenges, and handling failure constructively. Be authentic and specific—vague or generic answers are ineffective. For Junior level, focus on examples showing growth and learning rather than solo achievements or large-scale impact. Research the company's values thoroughly and align your answers with them (e.g., Meta values: Bold, Focus, Move Fast, Be Direct, Build Social Value). Prepare 2-3 thoughtful questions about the team, role expectations, learning opportunities, or how the team operates. Listen carefully to questions and answer what's being asked, not a prepared answer. Be honest about challenges—it's more impressive to discuss how you overcame challenges than to claim perfection. Throughout the interview, demonstrate genuine interest through active listening and insightful questions.
Focus Topics
Communication Skills & Clarity
Demonstrating ability to explain technical concepts to non-technical people clearly, articulate ideas and decisions logically, ask clarifying questions to ensure understanding, and listen actively. Showing thoughtful, structured communication throughout the interview that's easy to follow. Being able to discuss your work in a way that non-experts can understand.
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Study Questions
Problem-Solving & Taking Initiative
Examples of identifying problems proactively, taking initiative to solve them, and following through. Demonstrating analytical thinking and ability to break down complex problems. Showing that you don't just follow instructions but think about how to improve things. At Junior level, examples of solving problems within your scope, asking good questions, or suggesting improvements show maturity.
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Handling Challenges, Setbacks & Learning from Failure
Specific examples of challenges you've faced (missed deadlines, difficult bugs, conflicts with colleagues, steep learning curves, projects that didn't go as planned). How you handled them, what you learned, and how you've applied that learning. Being honest about struggles while demonstrating resilience, problem-solving, and growth. Showing that setbacks are learning opportunities rather than occasions for blame or excuses.
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Company Values & Cultural Alignment
Understanding the company's core values (e.g., Meta: Be Bold, Focus, Move Fast, Be Direct, Build Social Value; Google: User Focus, Innovation, Integrity, Collaboration; Amazon: Customer Obsession, Ownership, Learn and Be Curious, Hire and Develop Best). Providing specific examples from your experience that align with these values. Discussing why the company's mission and culture appeal to you beyond compensation.
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Study Questions
Coachability & Growth Mindset
Demonstrating genuine openness to feedback, ability to learn from mistakes, and commitment to continuous improvement. Providing specific examples of receiving critical feedback and responding constructively rather than defensively. Discussing areas where you've improved and learned. Showing that you actively seek feedback and learning opportunities rather than being defensive about weaknesses.
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Collaboration & Teamwork
Specific examples of working effectively with teammates, designers, backend developers, QA, or other disciplines. Demonstrating ability to communicate clearly, listen to others' perspectives, resolve disagreements constructively, contribute to team success, and support colleagues. Understanding your role within a team and how your work connects to the bigger picture. Showing humility and willingness to help others.
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Frequently Asked Frontend Developer Interview Questions
Sample Answer
// dispatch
document.dispatchEvent(new CustomEvent('filter:change', { detail: { q:'a' } }));
// listen
const onFilter = e => { /*...*/ };
document.addEventListener('filter:change', onFilter);
// cleanup
document.removeEventListener('filter:change', onFilter);const bus = { subs: {}, on(k,f){(this.subs[k]=this.subs[k]||[]).push(f); return ()=>this.off(k,f)}, emit(k,p){(this.subs[k]||[]).forEach(f=>f(p))}, off(k,f){this.subs[k]=this.subs[k].filter(x=>x!==f)} };const AppContext = createContext();
function Provider({children}){ const [state,set]=useState({filter:null}); return <AppContext.Provider value={{state,set}}>{children}</AppContext.Provider>}
function useApp(){ return useContext(AppContext); }Sample Answer
import React, { useReducer } from 'react';
const initialState = { count: 0 };
function reducer(state, action) {
switch (action.type) {
case 'increment':
return { count: state.count + 1 };
case 'decrement':
return { count: state.count - 1 };
case 'increment-by':
return { count: state.count + (action.payload || 0) };
case 'reset':
return initialState;
default:
throw new Error('Unknown action: ' + action.type);
}
}
export default function Counter() {
const [state, dispatch] = useReducer(reducer, initialState);
return (
<div>
<p>Count: {state.count}</p>
<button onClick={() => dispatch({ type: 'decrement' })}>-</button>
<button onClick={() => dispatch({ type: 'increment' })}>+</button>
<button onClick={() => dispatch({ type: 'increment-by', payload: 5 })}>
+5
</button>
<button onClick={() => dispatch({ type: 'reset' })}>Reset</button>
</div>
);
}Sample Answer
Sample Answer
// App.jsx
import React, { useState } from 'react';
import ExpensiveChild from './ExpensiveChild';
export default function App(){
const [count, setCount] = useState(0);
return (
<div>
<button onClick={() => setCount(c => c + 1)}>Inc {count}</button>
{/* inline arrow creates new fn each render */}
<ExpensiveChild onAction={() => console.log('action')} />
</div>
);
}
// ExpensiveChild.jsx
import React, { useRef } from 'react';
export default function ExpensiveChild({ onAction }){
const renders = useRef(0);
// simulate expensive work
for(let i=0;i<5e6;i++){}
renders.current++;
console.log('ExpensiveChild renders:', renders.current);
return <button onClick={onAction}>Child</button>;
}import React, { useState, useCallback } from 'react';
import ExpensiveChild from './ExpensiveChild';
export default function App(){
const [count, setCount] = useState(0);
const onAction = useCallback(() => console.log('action'), []); // stable identity
return (
<div>
<button onClick={() => setCount(c => c + 1)}>Inc {count}</button>
<ExpensiveChild onAction={onAction} />
</div>
);
}const t0 = performance.now(); clickNtimes(5); const t1 = performance.now();
console.log('duration ms', t1-t0);Sample Answer
Sample Answer
// returns array pi of length m
function buildPrefix(P) {
const m = P.length;
const pi = new Array(m).fill(0);
let k = 0; // length of current longest prefix-suffix
for (let i = 1; i < m; i++) {
while (k > 0 && P[k] !== P[i]) {
k = pi[k - 1]; // fallback
}
if (P[k] === P[i]) k++;
pi[i] = k;
}
return pi;
}Sample Answer
Sample Answer
function createWidget(container) {
const el = document.createElement('div');
el.className = 'widget';
const handler = () => console.log(el.textContent);
el.addEventListener('click', handler);
container.appendChild(el);
// later:
// el.removeEventListener('click', handler);
// el.remove();
}el.addEventListener('click', function (e) {
console.log(e.currentTarget.textContent);
});container.addEventListener('click', (e) => {
const w = e.target.closest('.widget');
if (w) console.log(w.textContent);
});Sample Answer
import { useEffect, useRef } from 'react';
function useLatest(fn) {
const ref = useRef(fn);
useEffect(() => { ref.current = fn; }, [fn]);
return ref;
}
function MyComponent({ socket, someProp }) {
const handleEvent = (event) => {
// uses latest someProp safely because we update the ref
console.log('current prop:', someProp, 'event:', event);
};
const latestHandlerRef = useLatest(handleEvent);
useEffect(() => {
// subscribe once
const wrapper = (event) => {
// delegate to latest handler implementation
latestHandlerRef.current(event);
};
socket.on('message', wrapper);
return () => { socket.off('message', wrapper); };
}, [socket, latestHandlerRef]); // socket may change; ref is stable
}Sample Answer
// Example: focus trap on open
const previous = document.activeElement;
modal.setAttribute('aria-modal', 'true');
modal.setAttribute('role', 'dialog');
modal.querySelector('[data-autofocus]')?.focus();
// on close: previous.focus();Recommended Additional Resources
- Frontend Interview Handbook (frontendinterviewhandbook.com) - Comprehensive guide with JavaScript, HTML/CSS, system design, and quiz preparation specifically for frontend developer interviews
- GreatFrontEnd (greatfrontend.com) - Interactive platform with curated frontend coding and UI component practice questions from real FAANG interviews with detailed solutions
- LeetCode - Practice coding problems; focus on Easy to Medium difficulty for Junior level preparation, particularly arrays, strings, and basic algorithms
- MDN Web Docs (developer.mozilla.org) - Authoritative reference for JavaScript, HTML, CSS, Web APIs, and browser features; use for deepening fundamental knowledge
- JavaScript.info - Excellent free resource for understanding JavaScript fundamentals, async operations, closures, prototypes, and DOM manipulation with interactive examples
- CSS-Tricks - In-depth articles and guides on CSS techniques, Flexbox, Grid, responsive design, and modern CSS patterns
- Cracking the Coding Interview by Gayle Laakmann McDowell - Classic reference book for understanding interview preparation strategies and problem-solving approaches
- You Don't Know JS Series by Kyle Simpson - In-depth JavaScript book series for deeply understanding scope, closures, the this keyword, async operations, and JavaScript internals
- React Official Documentation (react.dev) - Primary resource for learning React, hooks, component patterns, and best practices from the React team
- Egghead.io - Video courses on React, JavaScript fundamentals, and web development from experienced instructors
- Frontend Masters (frontendmasters.com) - High-quality video courses on frontend technologies and best practices from industry experts and framework creators
- CodePen & CodeSandbox - Online editors for practicing component building and running code without setting up local development environments
- GeeksforGeeks Frontend Interview Questions - Curated lists of frontend interview questions organized by difficulty level with explanations
- Meta Engineering Blog, Google Developers Blog, Amazon Tech - Company-specific technical blogs to understand technical priorities, innovations, and engineering culture
- Figma, Adobe XD - Understanding design tools to better collaborate with designers and implement designs pixel-accurately
- Web Accessibility by WAI (w3.org/WAI) - Comprehensive guides on web accessibility principles and WCAG standards to build inclusive applications
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