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

← Zeta

Senior Backend at Zeta

BackendSeniorNo offer◆ Commonly asked· 2024

6-round senior backend 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.

  • Word ladder — shortest transformation sequence.
    SeniorHard◆ Commonly asked
    #bfs#graph
    PracticeLeetCode↗GeeksforGeeks↗
  • Kth smallest element in a BST.
    SeniorMedium◆ Commonly asked
    #tree#bst
    PracticeLeetCode↗GeeksforGeeks↗
  • Merge k sorted lists.
    SeniorHard◆ Commonly asked
    #heap#linked-list
    PracticeLeetCode↗GeeksforGeeks↗
02

Round 02 · 2 questions

Machine Coding

Build a working component or service under time pressure.

  • Build a key-value store with TTL expiry.
    SeniorMedium◆ Commonly asked
    #cache#ttl
    PracticeGeeksforGeeks↗Search↗
  • Implement a token-bucket rate limiter as a service.
    SeniorMedium◆ Commonly asked
    #rate-limit
    PracticeGeeksforGeeks↗Search↗
03

Round 03 · 2 questions

System Design

High-level architecture of a large-scale system.

  • Design a feature-flag service.
    SeniorMedium◆ Commonly asked
    #config#rollout
    PracticeGeeksforGeeks↗Search↗
  • Design an analytics / metrics dashboard backend.
    SeniorHard◆ Commonly asked
    #time-series#aggregation
    PracticeGeeksforGeeks↗Search↗
04

Round 04 · 3 questions

Tech Deep-Dive

Deep questions on your core stack and fundamentals.

  • How does a load balancer choose a backend?
    SeniorMedium◆ Commonly asked
    #networking
    PracticeGeeksforGeeks↗Search↗
  • What is a deadlock and how do you avoid one?
    SeniorHard◆ Commonly asked
    #concurrency
    PracticeGeeksforGeeks↗Search↗
  • Explain how a hash index differs from a B-tree index.
    SeniorHard◆ Commonly asked
    #databases#indexing
    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.

  • When did you take ownership of something outside your scope?
    Senior◆ Commonly asked
    #ownership#star
  • Tell me about a time you led without a title.
    Senior◆ Commonly asked
    #leadership#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.