Mozilla Frontend Engineer Interview Questions
& Process
Real candidates share what happened, how many rounds they had,
and how the experience turned out.
Based on 5 interview experiences · FREE TO READ
Candidate interview experiences
First-hand accounts from people who interviewed at Mozilla.
Mozilla
Frontend Engineer
Mid Difficult Negative experience No offer 5 rounds
Interview process
Recruiter call Phone screen Technical screen Onsite Panel
Interview formats
Behavioral Technical Coding Other
It started with a recruiter screen, then a behavioural interview, followed by a 4 round loop. The loop included another behavioural interview, a technical interview with pair programming, a conversational technical interview, and a code review. I think I did well in all but one. They mentioned they wanted to hire quickly, but I didn't hear back for 2.5 weeks after the last round. It was unfortunate not to get any feedback after spending so much time talking with them.
Confirmed questions1 question
- Could you write an async function that takes an array of async functions (providers), each returning an array and a promise, and logs the results in ascending order based on position?
Mozilla
Front End Engineer
Entry Average Neutral experience No offer 3 rounds
Interview process
Take home Recruiter call Technical screen
Interview formats
Coding Behavioral
I got an email with a hacker rank coding challenge, then a phone screen, and then another email. I finished the coding challenge by the end of the week. A few days later, they called for a follow-up and asked some background questions. A couple more days passed and I got an email saying my hacker rank score wasn't high enough. I asked for more specific feedback, but the recruiter didn't respond. It seemed odd to have a phone screen after failing the coding challenge, but it didn't take up too much of my time.
Confirmed questions2 questions
- Could you build a basic interface using HTML and CSS?
- Please add functionality to a TODO snippet using vanilla JavaScript, specifically for adding and deleting todos.
Mozilla
Front-End Developer
Entry Difficult Positive experience No offer 2 rounds
Interview process
Take home Phone screen
Interview formats
Coding
I applied for the front-end developer role on Mozilla careers and the next day got an email with a link to a HackerRank Code challenge. They promised a phone interview would be scheduled after passing the challenge. The challenge required more programming languages than what was listed on the job description, which was unexpected. The results were emailed a few days after finishing the test.
Confirmed questions2 questions
- The HackerRank Code challenge included 5 multiple choice questions that weren't too difficult.
- The HackerRank Code challenge also had 2 code questions that were a bit difficult.
Mozilla Frontend Engineer Interview Questions
Quoted word for word from Mozilla interview reports.
“Please add functionality to a TODO snippet using vanilla JavaScript, specifically for adding and deleting todos.”
Read reports →“Can you create tabs using HTML, CSS, and JS?”
Read reports →“Could you write an async function that takes an array of async functions (providers), each returning an array and a promise, and logs the results in ascending order based on position?”
Read reports →“The HackerRank Code challenge also had 2 code questions that were a bit difficult.”
Read reports →“Could you build a basic interface using HTML and CSS?”
Read report →“The HackerRank Code challenge included 5 multiple choice questions that weren't too difficult.”
Read report →“Can you share an instance where you devised a clever solution to a challenge you encountered?”
Read report →Formats, difficulty and experience
Across all 5 Mozilla interview reports.