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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
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- 546
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- 11
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Showing 1321–1350 of 2810 results
- J.P. MorganMediumSoftware EngineerReview a PR for thread-safe request handling
This problem tests your ability to identify race conditions and thread-safety issues in a concurrent service and suggests robust design patterns for handling shared resources.
Software Engineering FundamentalsTechnical ScreenConcurrencyThread-SafetyDesign Patterns - J.P. MorganMediumSoftware EngineerReview concurrent code quality
This question tests your ability to identify thread-safety issues, improper synchronization, and architectural code smells within a multi-threaded data processing class.
Software Engineering FundamentalsTechnical ScreenConcurrencyJavaThread-Safety - Jane StreetMediumSoftware EngineerBottom-Insertion Connect Game: Detect the First k-in-a-Row Winner
This question evaluates simulation and algorithmic problem-solving skills, focusing on state maintenance for an unbounded grid, efficient detection of k-in-a-row runs in rows and columns, and handling column-wise shifts that can produce simultaneous winners.
Coding & AlgorithmsTechnical Screen - Jane StreetHardSoftware EngineerDecode an Encrypted Paragraph Tree
This question evaluates skills in string parsing, tree serialization/deserialization, and bijective substitution cipher handling, assessing competency in parsing nested structures, character mapping, and traversal within the Coding & Algorithms domain.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumSoftware EngineerDesign Exchange and Instrument Abstractions for Quote Arbitrage
Design an in-memory cross-exchange quote aggregator and arbitrage detector that identifies profitable, actionable price discrepancies while handling invalid spreads, quote staleness, and order sizing.
Software Engineering FundamentalsTechnical ScreenLow-Level DesignTrading SystemsData Structures - Jane StreetMediumSoftware EngineerEvaluate Expressions with Strictly Positive Integer Intermediate Results
Evaluate arithmetic expressions with a supplied decomposition helper, rejecting nonpositive or fractional intermediate results and preserving exact integer division.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumSoftware EngineerImplement a Circular Buffer
Implement a fixed-capacity circular buffer (ring buffer) supporting constant-time FIFO operations using wraparound indexing.
Coding & AlgorithmsTechnical ScreenData StructuresQueueArray - Jane StreetHardSoftware EngineerOptimal Stopping with Square-Number Ruin
Analyze an optimal stopping game where a player rolls a fair six-sided die to accumulate points but busts if the running sum hits a positive perfect square. Tests dynamic programming, renewal theory intuition, and rigorous edge-case analysis under uncertain stopping boundaries.
Statistics & MathTechnical Screenprobabilityoptimal-stoppingdynamic-programming - Jane StreetHardSoftware EngineerOptimize a Two-Box Place-or-Take Game
Analyze and optimize a 100-turn, two-box stochastic game with capacity constraints and opaque states. Derive the optimal decision policy, examine boundary/edge cases, and evaluate how the strategy changes when core assumptions are relaxed.
Statistics & MathTechnical ScreenProbabilityDynamic ProgrammingMarkov Decision Process - Jane StreetMediumSoftware EngineerPayout-Split Formula Where Every Step Is a Whole Positive Share
Write a parser and evaluator for arithmetic formulas that describe splitting a prize pool into whole-unit shares, where every intermediate computed amount must be a positive whole number or the entire formula is rejected. Tests recursive-descent parsing combined with evaluation rules where a single bad step invalidates the whole result.
Coding & AlgorithmsTechnical Screenparsingrecursionarithmetic - Jane StreetMediumSoftware EngineerProcess One Million Quote Updates per Second
Design a low-latency market data processing engine capable of ingesting 1,000,000 quote updates per second across multiple exchanges, maintaining global best bids and asks, and triggering immediate cross-venue arbitrage alerts.
System DesignTechnical ScreenLow LatencyConcurrencyTrading Systems - Jane StreetHardSoftware EngineerReach a Target Using Each Number At Most Once
This question evaluates the ability to construct arithmetic expressions from a multiset of numbers and reason about combinatorial search, operator composition, parenthesization, and exact rational arithmetic under constraints.
Coding & AlgorithmsTechnical Screen - Jane StreetHardSoftware EngineerSnake Game: Minimum Moves to Reach the Apple
This question evaluates proficiency in state-space modeling, constrained grid pathfinding, and dynamic collision handling, testing skills in shortest-path reasoning and movement legality within the Coding & Algorithms domain; the level of abstraction is practical application of algorithmic techniques to simulate evolving game states rather than purely theoretical analysis. It is commonly asked in technical interviews because it requires reasoning about evolving constraints and reachable states, demonstrating an applicant's ability to model complex movement rules and perform effective search under limited grid and body-size constraints.
Coding & AlgorithmsTechnical Screen - Jane StreetEasySoftware EngineerStack Machine Interpreter with Typed Int and String Values
This question evaluates understanding of stack-machine semantics, runtime type representation and preservation of distinct integer versus string values, plus handling mixed-type ADD behavior and output semantics.
Coding & AlgorithmsTechnical Screen - Jane StreetMediumSoftware EngineerTurning Interview Code into a Reusable Library or API
This question evaluates a candidate's skills in software design and engineering practices, including modularization, API and library interface design, documentation and typing, robustness and error handling, testing, packaging, versioning, and state/transport considerations.
Software Engineering FundamentalsTechnical Screen - Jane StreetMediumSoftware EngineerWrite an Interpreter for a Small Language with Load, Store and Arithmetic
Practice writing an interpreter for a small language with load, store and integer arithmetic instructions, using an assumed stack-based specification. It tests parsing source text into instructions, executing them with correct operand order, and reporting errors such as stack underflow, undefined variables and division by zero.
Software Engineering FundamentalsTechnical Screen - Jump TradingHardSoftware EngineerAccelerate Tree-Model Inference
Design an end-to-end strategy to accelerate inference latency and throughput for an existing gradient-boosted decision tree (GBDT) model in a low-latency trading environment while preserving exact prediction fidelity. Address feature engineering constraints, low-level execution optimizations, verification of numerical equivalence, and production drift monitoring.
Machine LearningTechnical ScreenTree ModelsInference OptimizationLow-Latency Systems - Jump TradingEasySoftware EngineerDesign Stack Evaluators and Low-Latency Memory Primitives
This question tests your understanding of low-latency systems programming, focusing on thread-safe memory management, cache locality, and efficient expression parsing.
Software Engineering FundamentalsTechnical ScreenC++ConcurrencyLow-Latency - Jump TradingHardSoftware EngineerDesign a Compact Columnar File Format
Design an append-friendly, compact columnar file format optimized for fast analytical scans over tabular financial market data (e.g., tick feeds or order book snapshots). Define the on-disk binary layout, reader/writer abstractions, serialization rules, and operational trade-offs.
Software Engineering FundamentalsTechnical Screensystems-designfile-formatscolumnar-storage - Jump TradingMediumSoftware EngineerExplain C++ vector, unordered_map, and virtual functions
Explain C++ vector, unordered_map, and virtual functions 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 & AlgorithmsTechnical Screen - Jump TradingEasySoftware EngineerFind the Largest Equivalence Class of Fractions
This problem tests your ability to handle numerical equivalence using canonical representations to avoid floating-point precision issues.
Statistics & MathTechnical ScreenMathHash MapNumber Theory - Jump TradingEasySoftware EngineerLargest Subset With Positive Bitwise AND
This problem tests your understanding of bitwise operations and greedy array partitioning to maximize the size of a subset that results in a non-zero bitwise AND.
Coding & AlgorithmsTechnical ScreenBit ManipulationGreedyArrays - KaratMediumSoftware EngineerJoin tables to map userId to name
This question evaluates a candidate's skills in relational data joining, data integration, and numeric reconciliation for mapping userId to customerName across multiple tables.
Coding & AlgorithmsTechnical Screen - KaratMediumSoftware EngineerValidate password and list rule violations
This question evaluates string-processing and input-validation skills, including case-insensitive substring detection, character class checks, pattern matching for special symbols, and handling edge cases like consecutive character limits.
Coding & AlgorithmsTechnical Screen - KikoffEasySoftware EngineerBuild a Robust Log Parser and Prefix-Operator Search
Implement a log parser and query engine that converts raw server log lines into structured records and supports filtering via prefix-operator tokens.
Software Engineering FundamentalsTechnical ScreenString ParsingData StructuresSoftware Architecture - KikoffMediumSoftware EngineerParse CSV and format transactions
This question evaluates a candidate's ability to parse and format structured transactional data, emphasizing CSV parsing, trimming whitespace, numeric formatting to two decimal places, and preserving input row order.
Data Manipulation (SQL/Python)Technical Screen - KikoffEasySoftware EngineerValidate a Third-Party Identity Payload
Implement a pipeline that validates a third-party identity verification response against schema requirements and business rules while returning sanitized failure reason codes.
Software Engineering FundamentalsTechnical ScreenData ValidationPythonClean Code - LatentHardSoftware EngineerAdd Status, Pharmacist Worklists, and Digests to Prior Authorization
Design an event-driven prior authorization platform supporting real-time status tracking, prioritized pharmacist worklists, and scheduled email digests powered by asynchronous payer integrations.
System DesignTechnical ScreenEvent-DrivenHealthcareDistributed Systems - LayerzeroMediumSoftware EngineerChoose a Safe Polling Strategy for Delayed Records
Evaluate whether delayed arrivals can support a fixed polling interval that always yields exactly one new record. Use worst-case reasoning, then define a practical live contract covering observation limits, warm-up, buffering, cursors, deduplication, retries, out-of-order data, and multiple pollers.
Software Engineering FundamentalsTechnical Screen - Lead BankMediumSoftware EngineerImplement Stock Price Query APIs
This question evaluates skills in time-series data modeling, API and data-structure design, transactional (atomic) batch updates, concurrency control, and date/time parsing for stock price records.
Coding & AlgorithmsTechnical Screen
J.P. Morgan
Jane Street