Deloitte

Deloitte

Multinational professional services network with offices in over 150 countries.

4 Rounds ~21 Days Medium
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The Interview Loop

Recruiter Screen (30 min)

Standard fit check, behavioral questions, and resume overview.

Technical Loop (3-4 Rounds)

Deep dive into domain knowledge, coding, and system design.

Interview Question Bank

Backend Engineer • Behavioral • medium

Tell me about a time you had to push back on a client's technical request because it wasn't feasible or would introduce too much technical debt.

#Client Management #Communication #Negotiation
Practice
Backend Engineer • Behavioral • easy

Describe a situation where you had to explain a complex technical concept to a non-technical stakeholder or client.

#Stakeholder Management #Empathy #Clarity
Practice
Backend Engineer • Behavioral • medium

Tell me about a time you had a disagreement with a team member on a technical approach. How did you resolve it?

#Conflict Resolution #Teamwork #Collaboration
Practice
Backend Engineer • Behavioral • medium

Describe a time when a project requirement changed drastically midway through the sprint. How did you handle it?

#Agile #Flexibility #Prioritization
Practice
Backend Engineer • Behavioral • medium

Tell me about a time you found a critical bug in production. What was your step-by-step approach to resolving it?

#Incident Management #Debugging #Accountability
Practice
Backend Engineer • Behavioral • medium

How do you prioritize tasks when working on multiple client deliverables with conflicting deadlines?

#Organization #Prioritization #Communication
Practice
Backend Engineer • Behavioral • easy

Describe a time you went above and beyond to deliver value to a client.

#Initiative #Customer Focus #Value Creation
Practice
Backend Engineer • Behavioral • medium

Tell me about a time you had to learn a new technology stack quickly for a project.

#Adaptability #Self-Motivation #Learning Agility
Practice
Backend Engineer • Behavioral • medium

How do you ensure code quality and maintainability in a fast-paced consulting environment where deadlines are tight?

#Best Practices #Code Review #Testing
Practice
Backend Engineer • Behavioral • medium

Give an example of a time you identified a process improvement within your engineering team and successfully implemented it.

#Process Improvement #Initiative #Mentorship
Practice
Backend Engineer • Coding • easy

Given an array of integers nums and an integer target, return indices of the two numbers such that they add up to target. You may assume that each input would have exactly one solution, and you may not use the same element twice.

#Arrays #Hash Map
Practice
Backend Engineer • Coding • easy

Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

#Strings #Stack
Practice
Backend Engineer • Coding • medium

Given an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the non-overlapping intervals that cover all the intervals in the input.

#Arrays #Sorting
Practice
Backend Engineer • Coding • medium

Given an integer array nums and an integer k, return the k most frequent elements. You may return the answer in any order.

#Hash Map #Heap #Bucket Sort
Practice
Backend Engineer • Coding • medium

Given a binary search tree (BST), find the lowest common ancestor (LCA) node of two given nodes in the BST.

#Trees #Binary Search Tree #Recursion
Practice
Backend Engineer • Coding • medium

Write a SQL query to report the nth highest salary from the Employee table. If there is no nth highest salary, the query should report null.

#Database #Window Functions #Subqueries
Practice
Backend Engineer • Coding • medium

Write a SQL query to find employees who have the highest salary in each of the departments.

#Database #Joins #Group By
Practice
Backend Engineer • Coding • medium

Write a SQL query to find all overlapping date ranges for client project assignments in the Projects table.

#Database #Self Join #Date Functions
Practice
Backend Engineer • Coding • easy

Write a SQL query to delete all duplicate email entries in a table named Person, keeping only unique emails based on its smallest Id.

#Database #DELETE #Self Join
Practice
Backend Engineer • Coding • medium

Write a query to calculate the cumulative sum of revenue per month for a given client over the past year.

#Database #Window Functions #Aggregations
Practice
Backend Engineer • System Design • hard

Design a scalable REST API for a financial reporting dashboard used by enterprise clients. The data is updated nightly but queried heavily during business hours.

#API Design #Caching #Database Read Replicas
Practice
Backend Engineer • System Design • medium

Design a URL shortener service (like bit.ly). Focus on the database schema and the URL generation algorithm.

#Hashing #Database Design #Scalability
Practice
Backend Engineer • System Design • hard

Design a distributed rate limiter for a public-facing API to prevent abuse and enforce client-tier quotas.

#Distributed Systems #Algorithms #Redis
Practice
Backend Engineer • System Design • hard

How would you design a system to process and ingest millions of daily transaction records from various retail clients in different formats?

#Data Ingestion #ETL #Event-Driven Architecture
Practice
Backend Engineer • System Design • medium

Design a notification system that sends emails, SMS, and push notifications to users based on system events.

#Microservices #Asynchronous Processing #Third-party Integrations
Practice
Backend Engineer • Technical • medium

Explain the difference between Monolithic and Microservices architectures. What are the trade-offs, and when would you recommend one over the other to a client?

#Microservices #System Architecture #Consulting
Practice
Backend Engineer • Technical • medium

How does Spring Boot auto-configuration work under the hood? How would you disable a specific auto-configuration class?

#Java #Spring Boot #Annotations
Practice
Backend Engineer • Technical • hard

Explain ACID properties. How do you maintain transactional integrity in a distributed microservices architecture?

#Transactions #Distributed Systems #Saga Pattern #Two-Phase Commit
Practice
Backend Engineer • Technical • medium

Describe the differences between REST and GraphQL. When would you choose one over the other for a new enterprise client project?

#REST #GraphQL #Web Services
Practice
Backend Engineer • Technical • medium

How do you handle authentication and authorization in a microservices ecosystem?

#OAuth2 #JWT #API Gateway #Microservices
Practice
Backend Engineer • Technical • medium

What is the N+1 query problem in ORMs like Hibernate or Entity Framework, and how do you resolve it?

#ORM #Performance Optimization #SQL
Practice
Backend Engineer • Technical • easy

Explain the concepts of Dependency Injection and Inversion of Control. Why are they important in modern backend development?

#Software Design #Testing #Decoupling
Practice
Backend Engineer • Technical • hard

How would you optimize a slow-performing API endpoint that aggregates data from multiple downstream services?

#Concurrency #Caching #API Design #Asynchronous Processing
Practice
Backend Engineer • Technical • medium

Describe your experience with CI/CD. What are the key stages you would include in a deployment pipeline for a backend service?

#CI/CD #Testing #Deployment
Practice
Backend Engineer • Technical • hard

What are the differences between RabbitMQ and Apache Kafka? In what client scenario would you use Kafka over RabbitMQ?

#Message Brokers #Event Streaming #Kafka #RabbitMQ
Practice

Difficulty Radar

Based on recent AI-sourced data.

Meet Your Interviewers

The "Standard" Interviewer

Senior Engineer

Focuses on core competencies, system constraints, and clear communication.

Simulate

Unwritten Rules

Think Out Loud

Always explain your thought process before writing code or drawing architecture.

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