Front End Interviews — Definitive Overview and Preparation Guide

Front End Interviews are notoriously hard to prepare for. There are many possible interview formats and there isn't a standardized structure across the industry for evaluating front end engineers. Some companies use the same interview process for Front End Engineers as they do for generalist Software Engineers while some companies (e.g. Google and Amazon) do a mix where they have both general software engineering rounds and front end domain-specific rounds.

In recent years, the industry is gradually shifting away from asking front end interview candidates to solve data structures and algorithms (DSA) questions. Instead, candidates will have to implement common front end library functions and/or build practical UI components/apps which tests their understanding of practical and relevant front end concepts. This is an encouraging trend because unlike most DSA questions, front end interview questions are highly relevant to a front end engineer's day-to-day responsibilities and is a more accurate assessment.

However, many existing software engineering interview resources are geared towards general software engineering roles instead of Front End Engineers which is a much smaller and niche field; you can barely find any resources on Front End System Design. These factors combined with the breadth of possible domain topics makes preparing for front end interviews a long, tedious, and tough process.

Fear not! GreatFrontEnd aims to be the best resource for Front End Engineers to ace their front end interviews by being a one-stop platform to equip Front End Engineers with the necessary knowledge and practice. On GreatFrontEnd, readers can:

1. Learn how to create an awesome resume tailored for Front End Engineering job listings.
2. Learn important front end concepts and techniques that apply to all question types.
3. Prepare for the most common front end interview question types (coding, system design, quiz, behavioral).
4. Practice questions across the most common front end interview formats along with high quality solutions written by ex-FAANG Senior Engineers.
5. Browse suggested study plans and adopt a structured preparation approach.

Prepare an Awesome Resume​

Your resume is the first opportunity to make an impression on potential employers and is crucial for getting shortlisted at your dream companies.

If you are facing difficulties getting interviews for jobs you apply to despite having the necessary qualifications, it could be because of your resume. Even highly qualified candidates may not know how to effectively present their accomplishments in their resume and therefore may not get shortlisted. It is important to remember that being underqualified is not always the reason for not being selected; sometimes it is simply a matter of poor presentation and not including the important content. Once you have made it through the resume screening process, your past achievements are secondary and your technical skills become paramount, which can be learned and improved upon. Hence getting your foot in the door by submitting a great resume that represents you well is extremely important.

While there are existing resources on how to make a good Software Engineering resume such as the Tech Interview Handbook and FAANG Tech Leads' Resume Handbook, they are general and not specific to Front End Engineers. We have written some tips on how to tailor your resume for Front End Engineering positions.

Prepare by Question Types​

There are many different formats a front end interview loop can be conducted and each company does things differently. To be efficient in your preparation, you should find out the different interview stages of the companies you are interviewing with, the various rounds within each stage, and the question types you will be asked in each round.

Each question format has its own challenges and quirks. We'll introduce you to the various formats and you can read the dedicated pages for each type if you'd like to find out more.

Coding Questions​

Coding questions will involve writing code (duh!). However, the code you will be required to write and the platforms you will write the code on can vary wildly. You could be asked about:

1. Algorithmic Coding: Solve tricky algorithmic questions that evaluates your understanding of data structures, algorithms and time complexity. Read about Algorithmic Coding Interviews.
2. JavaScript Coding: Implement functions or data structures in JavaScript that are related to front end domain and commonly used during front end development. Read about JavaScript Coding Interviews.
3. User Interface Coding: Build user interfaces (components, widgets, apps) using HTML, CSS, and JavaScript, sometimes even using JavaScript frameworks. Read about User Interface Coding Interviews.

Companies are trending towards using domain-specific coding questions and less on testing about algorithms and data structures as the former is more relevant for evaluating the core skills needed for front end engineering work.

System Design Questions​

System Design interviews are highly open-ended interviews that involve coming up with a software system design to solve a vague problem or scenario. Candidates will have to break down a system into smaller components, draw architecture diagrams, design APIs, dive into certain parts of the system and discuss tradeoffs in order to succeed.

System design interviews are usually only given to senior level candidates and the required systems can be one of the following types and examples:

1. Distributed systems: Twitter back end, URL shortener
2. Client applications: Newsfeed, Photo sharing applications
3. Complex user interface components: Autocomplete, Dropdown menu, Modal

Most of the time, Front End Engineers will be asked to design client applications and complex user interface components as those products are more relevant to front end engineering.

Read more about Front End System Design

Quiz Questions​

Quiz questions, also known as trivia questions, are short questions meant to test your understanding of the domain. Each question shouldn't take more than a minute or two to answer.

There usually wouldn't be entire interview rounds just asking you quiz questions, but they could be sprung onto you in the middle of other interview rounds.

Read more about Quiz Questions.

Behavioral Questions/Interviews​

In behavioral interviews, interviewer asks questions about your past behaviors and experiences in order to evaluate your suitability for the job and maturity level.

The idea behind behavioral interviews is that past behaviors and experiences are good indicators of how someone will behave in the future, so the interviewer will ask questions that are designed to get you to describe specific situations you have faced and how you have dealt with them in order to get a better understanding about you beyond your technical capabilities.

Behavioral interviews is a large topic on its own and we have written an entire guidebook on it.

Typical Hiring Process​

Most companies will have a process resembling:

1. Initial screen
   • Recruiter call (Quiz questions may be asked)
   • Autograded online assessments or take home projects
2. Phone screen
   • Coding (Implementing algorithms, JavaScript functions, or building user interfaces)
3. Full loop
   • Coding round (Implementing algorithms, JavaScript functions, or building user interfaces)
   • System design round
   • Behavioral round

The surest way to know what to expect is to ask the company recruiter about their interview process for the role. Good companies will even prepare a detailed document to explain each stage of the interview process along with resources to guide the candidates to prepare for the interviews. For big companies that see a large volume of applicants, there's a good chance that some candidates who have interviewed with them will share their experience on platforms like Glassdoor, Blind, and Reddit.

You must know what question types to expect in interviews, otherwise you'll be flying blind and not be able to prepare effectively.

Round-Type Matrix​

The following matrix shows the relevance/likelihood of each question type during each interview round. It's possible that an interview round can include questions from different question types.

Question Types Asked by Companies​

Here's a summary of the question types asked by the top US companies.

Question Type Legend

• Quiz: Closed ended quiz/trivia-style question.
• Algorithms: Implement a function that solves an algorithmic problem. It is usually not front end domain specific.
• JavaScript: Implement a function/class in JavaScript that is related to the front end domain.
• UI: Build a user interface using HTML/CSS/JavaScript. Some companies allow you to use a framework of your choice while some only allow Vanilla JS/certain frameworks.
• System Design: Design a system and discuss the architecture and its components.
• Behavioral: Discuss specific your experience working with others and how you handled difficult scenarios.

Study and Practice​

Read on to find out how to prepare for the following front end interview formats/questions types:

• Coding Questions
  • Algorithmic Questions
  • JavaScript Questions
  • User Interface Questions
• System Design Questions
• Quiz Questions