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Interview questions from top companies, mapped to the exact round they show up in. Prep for what you will actually face.

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Online AssessmentDSA / CodingMachine CodingLow-Level Design

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The Loop aggregates publicly shared interview experiences and curated commonly-asked questions, each labeled with its source. Not affiliated with any company listed.

CC BY-NC 4.0 · © 2026

← Niantic

Senior Frontend at Niantic

FrontendSeniorOutcome unknown◆ Commonly asked· 2023

6-round senior frontend process. Fast-paced; expect follow-ups that push on depth.

The loop · 6 rounds

01

Round 01 · 3 questions

DSA / Coding

Data structures & algorithms on a whiteboard or shared editor.

  • Diameter of a binary tree.
    SeniorEasy◆ Commonly asked
    #tree#dfs
    PracticeLeetCode↗GeeksforGeeks↗
  • Kth smallest element in a BST.
    SeniorMedium◆ Commonly asked
    #tree#bst
    PracticeLeetCode↗GeeksforGeeks↗
  • LRU cache with O(1) get and put.
    SeniorMedium◆ Commonly asked
    #hashmap#linked-list
    PracticeLeetCode↗GeeksforGeeks↗
02

Round 02 · 2 questions

Machine Coding

Build a working component or service under time pressure.

  • Build a "connect four" game with win detection.
    SeniorMedium◆ Commonly asked
    #react#state
    PracticeGeeksforGeeks↗Search↗
  • Build a countdown timer with pause and resume.
    SeniorEasy◆ Commonly asked
    #react#state
    PracticeGeeksforGeeks↗Search↗
03

Round 03 · 2 questions

System Design

High-level architecture of a large-scale system.

  • Design a component/design-system architecture for many teams.
    SeniorMedium◆ Commonly asked
    #frontend#design-system
    PracticeGeeksforGeeks↗Search↗
  • Design an object storage service like S3.
    SeniorHard◆ Commonly asked
    #storage#scale
    PracticeGeeksforGeeks↗Search↗
04

Round 04 · 3 questions

Tech Deep-Dive

Deep questions on your core stack and fundamentals.

  • Difference between CSS Grid and Flexbox — when to use each.
    SeniorEasy◆ Commonly asked
    #css#layout
    PracticeGeeksforGeeks↗Search↗
  • What causes layout thrashing and how do you avoid it?
    SeniorHard◆ Commonly asked
    #perf#dom
    PracticeGeeksforGeeks↗Search↗
  • Explain server components vs client components.
    SeniorHard◆ Commonly asked
    #react#ssr
    PracticeGeeksforGeeks↗Search↗
05

Round 05 · 1 question

Hiring Manager

Scope, ownership, and role-fit discussion with the manager.

  • What does a great engineering culture look like to you?
    Senior◆ Commonly asked
    #values
06

Round 06 · 2 questions

Behavioral / HR

Values, collaboration, and past-experience (STAR) questions.

  • Tell me about a time you disagreed and committed.
    Senior◆ Commonly asked
    #teamwork#star
  • Describe a conflict with your manager and the outcome.
    Senior◆ Commonly asked
    #conflict#star

Practice each round across every company

  • DSA / Coding
  • Machine Coding
  • System Design
  • Tech Deep-Dive
  • Hiring Manager
  • Behavioral / HR

◆ This experience is composed from commonly reported questions for this role and level. Real, individually-shared interviews will be layered in over time.