Mid Backend at Capital One

BackendMidNo offer◆ Commonly asked· 2023

Mid backend interview. Balanced across coding, design, and collaboration.

The loop · 5 rounds

Round 01 · 3 questions

DSA / Coding

Data structures & algorithms on a whiteboard or shared editor.

Maximum subarray (Kadane).
MidMedium◆ Commonly asked
#array#dp
PracticeLeetCode GeeksforGeeks
Word break.
MidMedium◆ Commonly asked
#dp#string
PracticeLeetCode GeeksforGeeks
Two Sum — return indices of numbers adding to a target.
MidEasy◆ Commonly asked
#array#hashmap
PracticeLeetCode GeeksforGeeks

Round 02 · 2 questions

Machine Coding

Build a working component or service under time pressure.

Build a webhook receiver with signature verification.
MidMedium◆ Commonly asked
#security#api
PracticeGeeksforGeeks Search
Build an in-memory pub/sub with topic subscriptions.
MidMedium◆ Commonly asked
#pub-sub
PracticeGeeksforGeeks Search

Round 03 · 1 question

Low-Level Design

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

Design a chess game (pieces, moves, board).
MidHard◆ Commonly asked
#oop
PracticeGeeksforGeeks Search

Round 04 · 3 questions

Tech Deep-Dive

Deep questions on your core stack and fundamentals.

Explain database indexing and when a query uses one.
MidMedium◆ Commonly asked
#databases#indexing
PracticeGeeksforGeeks Search
Message queues vs pub/sub — when to use each.
MidMedium◆ Commonly asked
#messaging
PracticeGeeksforGeeks Search
How does HTTPS/TLS establish a secure connection?
MidMedium◆ Commonly asked
#networking#security
PracticeGeeksforGeeks Search

Round 05 · 2 questions

Behavioral / HR

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

A time you influenced a decision without authority.
Mid◆ Commonly asked
#influence#star
Describe a time you disagreed with a teammate. How did it resolve?
Mid◆ Commonly asked
#conflict#star

◆ This experience is composed from commonly reported questions for this role and level. Real, individually-shared interviews will be layered in over time.