Backend Engineer Interview Preparation
Prepare for backend engineering interviews with system design, databases, and server-side programming questions.
Key Skills & Technologies
System Design
Database Design
API Development
Microservices
Caching
Scalability
Interview Focus Areas
System architecture and scalability
Database design and optimization
API design and REST principles
Caching strategies
Message queues and async processing
Security and authentication
Top Backend Engineer Coding Questions
Practice these 20 most relevant coding problems for backend engineer interviews.
#1
Recommended
#3594MediumFrequency: 100%
Identify the Largest Outlier in an Array
Hash TableArrayCountingEnumeration
#2
Recommended
#3655MediumFrequency: 100%
Digit Operations to Make Two Integers Equal
GraphMathHeap (Priority Queue)Number TheoryShortest Path
#3
Recommended
#3638HardFrequency: 100%
Minimum Operations to Make Character Frequencies Equal
Hash TableDynamic ProgrammingStringCountingEnumeration
#4
Recommended
#3613MediumFrequency: 100%
Maximize Amount After Two Days of Conversions
GraphArrayStringDepth-First SearchBreadth-First Search
#5
Recommended
#716HardFrequency: 100%
Max Stack
DesignLinked ListStackDoubly-Linked ListOrdered Set
#6
Recommended
#7
Recommended
#532MediumFrequency: 100%
K-diff Pairs in an Array
Hash TableArrayTwo PointersBinary SearchSorting
#8
Recommended
#1423MediumFrequency: 100%
Maximum Number of Occurrences of a Substring
Hash TableStringSliding Window
#9
Recommended
#10
Recommended
#295HardFrequency: 100%
Find Median from Data Stream
DesignTwo PointersSortingHeap (Priority Queue)Data Stream
#11
Recommended
#362MediumFrequency: 100%
Design Hit Counter
DesignArrayBinary SearchQueueData Stream
#12
Recommended
#314MediumFrequency: 97%
Binary Tree Vertical Order Traversal
Hash TableTreeDepth-First SearchBreadth-First SearchSortingBinary Tree
#13
Recommended
#14
Recommended
#15
Recommended
#1790MediumFrequency: 91%
Lowest Common Ancestor of a Binary Tree III
Hash TableTreeTwo PointersBinary Tree
#16
Recommended
#300MediumFrequency: 88%
Longest Increasing Subsequence
Dynamic ProgrammingArrayBinary Search
#17
Recommended
#18
Recommended
#647MediumFrequency: 88%
Palindromic Substrings
Dynamic ProgrammingTwo PointersString
#19
Recommended
#20
Recommended
All Interview Questions
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Topics & Algorithms
Practice by specific algorithm and data structure topics
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