theloop
CompaniesRoundsQuestionsSearchProgress
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 GitHub

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

← BlackRock

Senior Full-stack at BlackRock

Full-stackSeniorOffer◆ Commonly asked· 2024

Senior fullstack interview. Pragmatic questions — more real-world than pure puzzles.

The loop · 6 rounds

01

Round 01 · 3 questions

DSA / Coding

Data structures & algorithms on a whiteboard or shared editor.

  • Largest rectangle in histogram.
    SeniorHard◆ Commonly asked
    #stack#monotonic-stack
    PracticeLeetCode↗GeeksforGeeks↗
  • Find minimum in rotated sorted array.
    SeniorMedium◆ Commonly asked
    #binary-search
    PracticeLeetCode↗GeeksforGeeks↗
  • Maximum depth of a binary tree.
    SeniorEasy◆ Commonly asked
    #tree#dfs
    PracticeLeetCode↗GeeksforGeeks↗
02

Round 02 · 2 questions

Machine Coding

Build a working component or service under time pressure.

  • Build an infinite-scrolling list with virtualization.
    SeniorHard◆ Commonly asked
    #react#virtualization#perf
    PracticeGeeksforGeeks↗Search↗
  • Implement a JSON config loader with env overrides.
    SeniorEasy◆ Commonly asked
    #config
    PracticeGeeksforGeeks↗Search↗
03

Round 03 · 2 questions

System Design

High-level architecture of a large-scale system.

  • Design a ticket booking system (inventory + concurrency).
    SeniorHard◆ Commonly asked
    #concurrency#transactions
    PracticeGeeksforGeeks↗Search↗
  • Design a scalable frontend for an infinite feed (data, caching, rendering).
    SeniorHard◆ Commonly asked
    #frontend#virtualization#cache
    PracticeGeeksforGeeks↗Search↗
04

Round 04 · 3 questions

Tech Deep-Dive

Deep questions on your core stack and fundamentals.

  • Explain leader election and consensus (Raft) at a high level.
    SeniorHard◆ Commonly asked
    #distributed#consensus
    PracticeGeeksforGeeks↗Search↗
  • Explain memoization: useMemo, useCallback and React.memo.
    SeniorMedium◆ Commonly asked
    #react#perf
    PracticeGeeksforGeeks↗Search↗
  • What are React keys and why do they matter?
    SeniorEasy◆ Commonly asked
    #react
    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.

  • Why this company, and why this role?
    Senior◆ Commonly asked
    #motivation
  • Tell me about the most impactful project of your career.
    Senior◆ Commonly asked
    #impact#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.