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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

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Mid Frontend at Jar

FrontendMidWithdrew◆ Commonly asked· 2025

A mid frontend loop. Fast-paced; expect follow-ups that push on depth.

The loop · 5 rounds

01

Round 01 · 3 questions

DSA / Coding

Data structures & algorithms on a whiteboard or shared editor.

  • Invert a binary tree.
    MidEasy◆ Commonly asked
    #tree
    PracticeLeetCode↗GeeksforGeeks↗
  • LRU cache with O(1) get and put.
    MidMedium◆ Commonly asked
    #hashmap#linked-list
    PracticeLeetCode↗GeeksforGeeks↗
  • Regular expression matching.
    MidHard◆ Commonly asked
    #dp#string
    PracticeLeetCode↗GeeksforGeeks↗
02

Round 02 · 2 questions

Machine Coding

Build a working component or service under time pressure.

  • Build a virtualized chat window that loads older messages.
    MidHard◆ Commonly asked
    #react#virtualization
    PracticeGeeksforGeeks↗Search↗
  • Build a "Wordle" clone with keyboard input.
    MidMedium◆ Commonly asked
    #react#state
    PracticeGeeksforGeeks↗Search↗
03

Round 03 · 1 question

Low-Level Design

Object-oriented / low-level design of a focused module.

  • Design a client-side router.
    MidMedium◆ Commonly asked
    #oop#routing
    PracticeGeeksforGeeks↗Search↗
04

Round 04 · 3 questions

Tech Deep-Dive

Deep questions on your core stack and fundamentals.

  • Explain CORS and how a preflight request works.
    MidMedium◆ Commonly asked
    #browser#security
    PracticeGeeksforGeeks↗Search↗
  • How do you implement dark mode without a flash?
    MidMedium◆ Commonly asked
    #css#ssr
    PracticeGeeksforGeeks↗Search↗
  • localStorage vs sessionStorage vs cookies — when to use each?
    MidEasy◆ Commonly asked
    #browser
    PracticeGeeksforGeeks↗Search↗
05

Round 05 · 2 questions

Behavioral / HR

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

  • When did you have to make a decision with incomplete data?
    Mid◆ Commonly asked
    #judgment#star
  • Tell me about a time you failed and what you learned.
    Mid◆ Commonly asked
    #growth#star

Practice each round across every company

  • DSA / Coding
  • Machine Coding
  • Low-Level Design
  • Tech Deep-Dive
  • 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.