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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

← Palo Alto Networks

Mid Frontend at Palo Alto Networks

FrontendMidOutcome unknown◆ Commonly asked· 2023

5-round mid frontend process. Balanced across coding, design, and collaboration.

The loop · 5 rounds

01

Round 01 · 3 questions

DSA / Coding

Data structures & algorithms on a whiteboard or shared editor.

  • Longest palindromic substring.
    MidMedium◆ Commonly asked
    #string#dp
    PracticeLeetCode↗GeeksforGeeks↗
  • Largest rectangle in histogram.
    MidHard◆ Commonly asked
    #stack#monotonic-stack
    PracticeLeetCode↗GeeksforGeeks↗
  • Container with most water.
    MidMedium◆ Commonly asked
    #two-pointers#array
    PracticeLeetCode↗GeeksforGeeks↗
02

Round 02 · 2 questions

Machine Coding

Build a working component or service under time pressure.

  • Build a star-rating component (controlled + accessible).
    MidEasy◆ Commonly asked
    #react#a11y
    PracticeGeeksforGeeks↗Search↗
  • Build a to-do app with filters and localStorage persistence.
    MidEasy◆ 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.

  • Event delegation and how bubbling/capturing work.
    MidEasy◆ Commonly asked
    #dom
    PracticeGeeksforGeeks↗Search↗
  • How does React reconciliation / the diffing algorithm work?
    MidMedium◆ Commonly asked
    #react#fiber
    PracticeGeeksforGeeks↗Search↗
  • What is tree shaking and when does it fail?
    MidMedium◆ Commonly asked
    #bundling
    PracticeGeeksforGeeks↗Search↗
05

Round 05 · 2 questions

Behavioral / HR

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

  • Describe something you shipped that you were not proud of.
    Mid◆ Commonly asked
    #tradeoffs#star
  • Tell me about the most impactful project of your career.
    Mid◆ Commonly asked
    #impact#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.