Frontend Interview Experience | Paytm Software Engineer — Frontend | 0–2 years experience

Overview

This document details the interview experience of a frontend engineer candidate (0-2 years of experience) at Paytm. The process assessed the candidate's proficiency in JavaScript, React, problem-solving skills, and understanding of frontend architecture.

Interview Rounds

Round 1: Online Assessment

This round was not detailed extensively but it is implied that basic DSA knowledge will be helpful.

Round 2: Technical Round 1

The initial discussion covered the candidate's background and previous experience. The technical assessment involved:

• A mathematical problem requiring the construction of an input array from an output array of averages.
• Implementation of a custom polyfill for Object.flat, mimicking the functionality of Array.flat.
• Questions on core JavaScript concepts, including event loops, call stacks, and React hooks/functional components.

Round 3: Techno-Managerial

This round began with an in-depth discussion of the candidate's previous projects, product architecture, and challenging scenarios encountered. Following this, the candidate was presented with three problems:

• Designing an API contract for a lexicographically segregated list of cities (similar to a contact list).
• Developing the logic to traverse and render the list of cities from the API.
• Implementing fuzzy search functionality on the frontend (without API calls), including a reset function to clear the search and restore the original list (again, without API calls).

Key Takeaways

• Frontend interviews often require a strong foundation in core JavaScript concepts, including event loops, call stacks, and polyfills.
• Experience with React (or similar frameworks like Angular or Vue) is highly valuable.
• Problem-solving skills, particularly in the context of frontend challenges, are crucial.
• Understanding of API design and data manipulation is essential for frontend roles.
• The ability to articulate previous project experience and architectural decisions is important in techno-managerial rounds.