Technology and Engineering · #18 in series
Backend Engineer interview prep
Top 100 interview questions for Backend Engineer — modeled on real FAANG loops.
100
Questions
10
Topics
20
Free
System Design
10 questions1
How would you design a scalable URL shortening service like bit.ly?
hardsystem
2
Describe how you would design a distributed cache system.
easysystem
3
How would you design a video streaming platform like Netflix?
hardsystem
4
Explain the design considerations for a chat application like WhatsApp.
hardsystem
5
How would you design a file storage system like Dropbox?
hardsystem
6
Describe the architecture of a recommendation system.
easysystem
7
How would you design an online multiplayer game server?
hardsystem
8
What are the key components of designing a search engine?
hardsystem
9
How would you design a notification system?
hardsystem
10
Explain the design of a payment processing system.
hardsystem
Data Structures and Algorithms
10 questions11
How do you reverse a linked list?
mediumconcept
12
Explain how you would detect a cycle in a linked list.
mediumconcept
13
Describe the process of balancing a binary search tree.
easyconcept
14
How would you implement a queue using two stacks?
hardcoding
15
Explain the algorithm for finding the shortest path in a graph.
mediumcoding
16
How do you find the median of a large dataset?
mediumconcept
17
Explain the process of removing duplicates from a sorted array.
mediumconcept
18
How do you merge two sorted linked lists?
mediumconcept
19
Describe an algorithm to find the kth largest element in an array.
easycoding
20
How would you implement an LRU cache?
hardcoding
Databases
10 questions21
Explain the differences between SQL and NoSQL databases.
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22
How would you design a schema for a social media platform?
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23
What are the pros and cons of database normalization?
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24
How do you handle database migrations in a production environment?
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25
Describe how you would implement a full-text search in a database.
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26
What indexing strategies would you use for a large-scale database?
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27
How do you ensure data consistency in distributed databases?
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28
Explain the concept of sharding and its implementation.
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29
How would you design a database to handle time-series data?
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30
What are the key considerations for database backup and recovery?
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Networking
10 questions31
Explain the OSI model and its layers.
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32
How does HTTP differ from HTTPS?
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33
Describe how load balancing works and its importance.
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34
What are the differences between TCP and UDP?
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35
Explain the concept of RESTful APIs and their design principles.
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36
How does DNS resolution work?
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37
Describe the process of establishing a TCP connection.
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38
What is the role of a reverse proxy in a network?
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39
How do you handle network latency in distributed systems?
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40
Explain the concept of WebSockets and their use cases.
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Security
10 questions41
How would you secure a REST API?
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42
Describe the process of implementing OAuth 2.0 in an application.
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43
What are common vulnerabilities in web applications and how do you mitigate them?
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44
Explain the concept of Cross-Site Scripting (XSS) and its prevention.
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45
How do you ensure data encryption in transit and at rest?
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46
What is a man-in-the-middle attack and how do you prevent it?
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47
Describe the importance of input validation in security.
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48
How would you implement role-based access control in a system?
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49
Explain the concept of a secure hash algorithm.
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50
How do you perform security testing on a backend application?
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Performance Optimization
10 questions51
How do you identify and optimize slow database queries?
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52
What techniques would you use to optimize the performance of a web server?
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53
Describe how caching can improve system performance.
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54
How do you handle high load in a backend application?
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55
Explain the concept of rate limiting and its implementation.
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56
How would you optimize the performance of a REST API?
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57
Describe the process of profiling an application for performance bottlenecks.
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58
What are the benefits of using asynchronous processing in a backend application?
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59
How do you optimize memory usage in a backend system?
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60
What strategies would you use to optimize network throughput?
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Cloud Computing
10 questions61
How do you architect an application for cloud deployment?
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62
Explain the differences between IaaS, PaaS, and SaaS.
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63
How do you ensure high availability in a cloud environment?
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64
What are the benefits and challenges of using microservices in the cloud?
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65
How do you manage and monitor cloud resources?
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66
Describe how you would implement auto-scaling in a cloud application.
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67
How do you ensure data security in a cloud environment?
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68
Explain the concept of serverless architecture.
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69
What are the best practices for cloud cost optimization?
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70
How do you migrate an on-premises application to the cloud?
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DevOps and CI/CD
10 questions71
What is Continuous Integration and why is it important?
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72
How do you set up a CI/CD pipeline?
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73
Explain the role of Docker in a DevOps environment.
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74
How do you manage application configuration in different environments?
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75
Describe how you would implement infrastructure as code.
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76
What are the benefits of using containers in application deployment?
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77
How do you ensure application reliability through monitoring?
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78
Explain the concept of blue-green deployment.
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79
How do you handle logging in a distributed system?
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80
What is the role of Kubernetes in a DevOps workflow?
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Problem Solving and Debugging
10 questions81
Describe your approach to troubleshooting a production issue.
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82
How do you handle unexpected failures in a distributed system?
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83
Explain the process of debugging a memory leak in an application.
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84
How do you use logs to diagnose application issues?
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85
Describe a time when you had to solve a complex problem under pressure.
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86
How do you prioritize bugs in a backlog?
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87
What tools do you use for monitoring and debugging applications?
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88
How do you address concurrency issues in a multi-threaded application?
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89
Explain how you manage dependencies in a large codebase.
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90
How do you handle incomplete or ambiguous requirements?
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Behavioral Questions
10 questions91
Describe a challenging project you worked on and how you overcame obstacles.
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92
How do you handle conflicts within a team?
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93
What is your approach to learning new technologies?
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94
Describe a situation where you had to lead a team.
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95
How do you balance multiple priorities in a fast-paced environment?
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96
Explain a time when you received critical feedback and how you handled it.
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97
How do you ensure effective communication in a remote team?
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98
Describe a time when you had to adapt to significant changes in a project.
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99
What motivates you to work as a backend engineer?
🔒
100
How do you approach mentoring junior engineers?
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