theloop
CompaniesRoundsQuestionsSearchProgress
Frontend prep↗
theloop

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

View source

Browse

CompaniesSearchAll rounds

Rounds

Online AssessmentDSA / CodingMachine CodingLow-Level Design

Contribute

Share an interviewReport an issueStar on GitHubFrontend interview prep ↗

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

← LaunchDarkly

Senior Frontend at LaunchDarkly

FrontendSeniorOutcome unknown◆ Commonly asked· 2025

Senior frontend interview. Coding-heavy early, design and behavioral later.

The loop · 6 rounds

01

Round 01 · 3 questions

DSA / Coding

Data structures & algorithms on a whiteboard or shared editor.

  • Word break.
    SeniorMedium◆ Commonly asked
    #dp#string
    PracticeLeetCode↗GeeksforGeeks↗
  • Course Schedule II.
    SeniorMedium◆ Commonly asked
    #graph#topo-sort
    PracticeLeetCode↗GeeksforGeeks↗
  • Binary tree level order traversal.
    SeniorMedium◆ Commonly asked
    #tree#bfs
    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.
    SeniorHard◆ Commonly asked
    #react#virtualization
    PracticeGeeksforGeeks↗Search↗
  • Build a nested checkbox tree with indeterminate state.
    SeniorHard◆ Commonly asked
    #react#recursion
    PracticeGeeksforGeeks↗Search↗
03

Round 03 · 2 questions

System Design

High-level architecture of a large-scale system.

  • Design an online code judge / evaluator.
    SeniorHard◆ Commonly asked
    #sandboxing#queues
    PracticeGeeksforGeeks↗Search↗
  • Design a chat application like WhatsApp.
    SeniorHard◆ Commonly asked
    #websocket#fanout#storage
    PracticeGeeksforGeeks↗Search↗
04

Round 04 · 3 questions

Tech Deep-Dive

Deep questions on your core stack and fundamentals.

  • Explain hydration and the cost of client vs server rendering.
    SeniorHard◆ Commonly asked
    #ssr#perf
    PracticeGeeksforGeeks↗Search↗
  • Explain the difference between == and === and coercion.
    SeniorEasy◆ Commonly asked
    #javascript
    PracticeGeeksforGeeks↗Search↗
  • Explain prototypal inheritance.
    SeniorMedium◆ Commonly asked
    #javascript
    PracticeGeeksforGeeks↗Search↗
05

Round 05 · 1 question

Hiring Manager

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

  • How do you run an incident and the postmortem after?
    Senior◆ Commonly asked
    #reliability#process
06

Round 06 · 2 questions

Behavioral / HR

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

  • When did you change your mind after seeing new evidence?
    Senior◆ Commonly asked
    #judgment#star
  • When did you take ownership of something outside your scope?
    Senior◆ Commonly asked
    #ownership#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.