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Software Engineer Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
- 9403
- Questions
- 546
- Companies
- 11
- Topics
- 8
- Languages
Showing 1411–1440 of 5874 results
- ChimeHardSoftware EngineerDesign mobile check deposit system
This question evaluates a candidate's ability to design end-to-end, production-grade mobile check deposit systems, assessing competencies in system architecture, distributed systems, security and fraud prevention, regulatory compliance (Reg CC, Check 21), data durability, and operational observability.
System DesignOnsite - ChimeEasySoftware EngineerExplain sync/async, Go concurrency, SQL vs NoSQL
This question evaluates understanding of execution models (synchronous vs asynchronous and blocking vs non-blocking), Go concurrency patterns (goroutines, channels versus shared-memory with locks), and database paradigms (SQL vs NoSQL) relevant to backend engineering.
Software Engineering FundamentalsTechnical Screen - ChimeMediumSoftware EngineerImplement single-tab browser history navigation
This question evaluates understanding of data structures, stateful API behavior, amortized time complexity, set membership tracking, and edge-case handling for implementing browser-like history navigation in the coding & algorithms domain.
Coding & AlgorithmsTechnical Screen - ChimeMediumSoftware EngineerSimulate toppling board game outcome
This question evaluates a candidate's ability to implement a discrete board-game simulation, including state management, turn-based ownership semantics, stack-based piece handling, capture mechanics, and game termination detection.
Coding & AlgorithmsOnsite - CibcEasySoftware EngineerSelf-Introduction, Why This Role, Two Strengths and a Weakness, and a Java Self-Rating
A recruiter screen for a software engineer role asks for a self-introduction, the reason you want this role, two strengths and one weakness, and a self-rating of your Java skill backed by the courses you took. Tests concise self-presentation, honest calibration, and one coherent story across short answers.
Behavioral & LeadershipHR Screen - CircleMediumSoftware EngineerDescribe pair-programming challenge under time pressure
Describe pair-programming challenge under time pressure evaluates behavioral evidence, ownership, communication, trade-offs, and measurable outcomes in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Behavioral & LeadershipOnline Assessment - CircleHardSoftware EngineerDesign banking payment scheduling system
This interview question evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer for Design banking payment scheduling system states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnline Assessment - CircleHardSoftware EngineerDesign flight-price search service
Design flight-price search service evaluates requirements, scale assumptions, API/data design, architecture, trade-offs, failure modes, and rollout in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignOnline Assessment - CircleHardSoftware EngineerDesign in-memory DB with TTL and backup
A Circle software-engineer take-home: design a versioned in-memory key→(field→value) database with per-field TTL, append-only history and delete tombstones, lexicographically ordered scan and scanPrefix (correct even with special characters), and snapshot backup/restore counters. It exercises data modeling, time-travel visibility semantics, ordered indexing, garbage collection, and per-operation complexity trade-offs.
System DesignOnline Assessment - CircleHardSoftware EngineerImplement Recipe Storage CRUD
This question evaluates the ability to design and implement in-memory data structures and APIs for CRUD operations, covering skills such as ID generation and parsing, string handling for case-insensitive uniqueness constraints, data modeling, and preserving original value casing.
Coding & AlgorithmsTechnical Screen - CircleMediumSoftware EngineerImplement a simplified multi-level banking system
Implement a simplified multi-level banking system evaluates algorithm design, data structures, correctness, complexity, edge cases, and implementation details in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Coding & AlgorithmsOnline Assessment - CircleMediumSoftware EngineerImplement cheapest itinerary with date filters
This question evaluates proficiency in graph algorithms and constrained pathfinding, including handling date filters for initial departures, time-ordered connections, cycle avoidance, and quantitative complexity analysis.
Coding & AlgorithmsOnline Assessment - CircleMediumSoftware EngineerIn-Memory Bank System With Top-N Activity Ranking and Expiring Pending Transfers
Implement an in-memory banking class in stages: create accounts, deposit and pay, rank the top n accounts by transaction activity, and support transfers that hold funds until the recipient accepts within a time window or they are refunded. Tests state modeling, validation, and timestamp-driven expiry.
Software Engineering FundamentalsTechnical Screen - CircleMediumSoftware EngineerTrace and reduce redundant curl requests
A practical curl interview question on tracing and reducing redundant HTTP requests: instrumenting a curl-based client, finding duplicate calls, and cutting request volume. Includes a full worked solution.
System DesignOnline Assessment - CircleMediumSoftware EngineerWrite PostgreSQL updates with date filters
This question evaluates competency in PostgreSQL data manipulation, covering updates with correct timestamp handling, upserts with conflict resolution, date-range selection using timestamptz, and index design plus performance analysis with EXPLAIN ANALYZE.
Data Manipulation (SQL/Python)Online Assessment - CiscoEasySoftware EngineerDescribe How You Drove an Improvement to a Team's QA Workflow
A behavioral question for a software QA role asking how the candidate drives improvements to a team's testing and release workflow. It looks for a concrete, evidence-based example that shows root-cause diagnosis, a piloted change, stakeholder buy-in, and measured results.
Behavioral & LeadershipOnsite - CiscoEasySoftware EngineerDoes a Successful Ping Mean Port 443 Is Reachable? Diagnosing Server Connectivity
A networking fundamentals question asking whether a successful ping to a server proves that port 443 on it is accessible, and how to check the port directly. It tests the difference between ICMP and TCP, the role of firewalls and listening services, and practical connectivity troubleshooting with command-line tools.
Software Engineering FundamentalsOnsite - CiscoEasySoftware EngineerExplain BGP: Sessions, Route Exchange, and Best-Path Selection
A networking fundamentals question asking the candidate to explain the Border Gateway Protocol: why it exists, how peers form sessions and exchange routes, how a router selects the best path, and how BGP differs from interior protocols such as OSPF. It also probes troubleshooting and testing.
Software Engineering FundamentalsOnsite - CiscoHardSoftware EngineerFormalize a Minimum-Trip Transport Puzzle with Horses and Ladders
Model a horses-and-ladders transport puzzle by clarifying legal moves, tracking resource state, and proving a minimum-trip plan is optimal.
Statistics & MathTechnical Screen - CiscoEasySoftware EngineerImplement a Python To-Do Task Manager Class with CRUD and Status Rules
A Python coding question asking for a to-do task manager class with create, read, update, and delete operations, where every task has a status of new, pending, or resolved. It tests data modeling, input validation, status transition rules, error handling for missing tasks, and testable class design.
Software Engineering FundamentalsOnsite - CiscoHardSoftware EngineerImplement an LFU Cache
This problem tests your ability to design a data structure that supports O(1) insertions and lookups while managing cache eviction based on access frequency and recency.
Coding & AlgorithmsTechnical ScreenHash TableLinked ListDesign - CiscoEasySoftware EngineerLongest Substring Without Repeated Characters
This problem tests string manipulation, hash map usage, and the sliding window technique to find a specific substring based on unique character constraints.
Coding & AlgorithmsTechnical ScreenSliding WindowStringsHash Map - CiscoEasySoftware EngineerPython Multiple Inheritance: Which Parent Method Runs When Names Collide
A Python fundamentals question about multiple inheritance in which two parent classes define a method with the same name and a child class inherits from both. It tests the method resolution order, C3 linearization, how super() follows that order, and when composition is the better design.
Software Engineering FundamentalsOnsite - CiscoEasySoftware EngineerPython and pytest Fundamentals: Fixtures, Decorators, and Generators
A three-part Python and pytest fundamentals question covering how fixtures are injected, scoped, torn down, and shared; how decorators work and how to write one that preserves metadata; and how generators produce values lazily. It tests core language mechanics used in test automation.
Software Engineering FundamentalsOnsite - CiscoEasySoftware EngineerReason About C Pointer and Array Declarations
This question tests the ability to parse complex C declarations and understand memory layout, pointer arithmetic, and the differences between pointers and arrays.
Software Engineering FundamentalsTechnical ScreenCPointersMemory - CiscoMediumSoftware EngineerSolve max-subarray, min-unique, and grid-jump
This question evaluates array algorithms and algorithmic problem-solving skills, specifically contiguous-sum optimization (greedy/DP reasoning), frequency counting and memory-constrained selection for unique minima, and grid traversal simulation with boundary and visit-state management.
Coding & AlgorithmsOnline Assessment - CiscoEasySoftware EngineerTesting a New Feature: Planning Test Cases and Handling Flaky Tests
A two-part QA question on how to test a new feature and plan its test cases, and how to find, diagnose, and prevent flaky automated tests. It evaluates requirement analysis, test design techniques, risk-based prioritization, test levels, release exit criteria, and keeping a test suite trustworthy.
Software Engineering FundamentalsOnsite - CitadelHardSoftware EngineerBuild models for housing and wind power prediction
This question evaluates ML system design and applied modeling competencies, including data assumptions, preprocessing, feature engineering, model selection, validation strategies, temporal leakage handling, and end-to-end pipeline construction for a binary housing-affordability classifier and a time-series regression for wind-farm power prediction.
ML System DesignOnline Assessment - CitadelMediumSoftware EngineerChoose 200 of a Million Records to Label, Improving on Uniform Random Sampling
Tests the ability to define data informativeness under extreme budget constraints (selecting 200 out of 1,000,000 records) and design a scalable, one-shot sampling strategy that outperforms uniform random sampling in coverage and diversity.
Statistics & MathTechnical ScreenActive LearningSamplingClustering - CitadelMediumSoftware EngineerCompute BBO and NBBO from order data
This question evaluates a candidate's skill in designing efficient data structures and algorithms for aggregating and querying order-book data, including computing best bid/ask prices and summing quantities at those prices.
Coding & AlgorithmsTechnical Screen
Chime
Circle
Citadel