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Atomicwork SDE 1 Frontend Interview Experience

August 28, 20252 min read

Recently, I went through the interview process for an SDE 1 Frontend role at Atomicwork.

This experience was different from my other interviews because I didn’t clear the process, but it ended up teaching me a lot about frontend fundamentals.

About Me

I’m a frontend-leaning full-stack developer, currently working as a Founding Engineer at CredHive, where we build credit reporting and monitoring solutions for Indian companies and MSMEs.

My core strengths are React, TypeScript, and building highly interactive UI systems.

Interview Process Overview

  1. Recruiter Call
  2. Vanilla JavaScript Machine Coding Round

Recruiter Call

This was a standard screening round.

Questions

  • Current compensation
  • Notice period
  • Current role and responsibilities
  • Why looking for a change

Nothing unusual here — mainly checking alignment.

Round 2: Vanilla JavaScript Machine Coding

Problem

Build a progress bar that fills over a given amount of time.

Requirements

  • The progress bar should fill smoothly from 0 → 100
  • It should complete in a given duration (e.g., 5 seconds)
  • Should handle start / stop behavior
  • Clean and efficient implementation

My Approach

I tried implementing it using setInterval, updating the width of the progress bar over time.

While I was able to get something working, I struggled with:

  • Clearing intervals properly
  • Managing multiple timers
  • Handling edge cases

Where I Got Stuck

The interviewer went deeper into:

  • setTimeout vs setInterval
  • clearTimeout and clearInterval
  • Memory leaks
  • Browser timing APIs

I realized that I didn’t have a strong understanding of Web APIs and the event loop.

Because of that, I wasn’t able to confidently explain or improve my solution.

Result

I was not able to clear this round.

Biggest Learning

This interview made one thing very clear:

Strong UI skills alone are not enough — you need solid JavaScript fundamentals.

I was comfortable with React and building UI, but when it came to core JavaScript and browser APIs, I had gaps.

What I Did After This

After this interview, I spent time strengthening my fundamentals.

1. Web APIs

  • setTimeout, setInterval
  • clearTimeout, clearInterval
  • RequestAnimationFrame
  • Event loop