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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.
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Showing 2521–2550 of 9403 results
- CoinbaseMediumData ScientistWrite SQL: sum values ≤ each row’s value
This question evaluates proficiency in SQL aggregation, query optimization, and handling duplicate values when computing cumulative sums across rows. It is commonly asked to assess practical ability in the Data Manipulation (SQL/Python) domain to design scalable, efficient queries and demonstrates a focus on practical application of query-design and optimization rather than purely conceptual theory.
Data Manipulation (SQL/Python)Onsite - CollegevineMediumSoftware EngineerFind the Highest-Cost Top-Level Job
This question evaluates the ability to process hierarchical JSON data, aggregate durations across tree-structured job relationships, and reason about robustness and scalability concerns such as malformed input handling and performance for large datasets.
Coding & AlgorithmsTechnical Screen - Color HealthMediumSoftware EngineerBuild and Review an Employee Expense Reimbursement Application
This problem tests your ability to design a simple RESTful API and implement core CRUD operations with server-side validation for an expense tracking system.
Software Engineering FundamentalsTechnical ScreenAPI DesignCRUDValidation - CommureMediumSoftware EngineerDesign Monthly Artist Payouts from Streaming Counts
Design a monthly artist-payout system that turns valid streaming events into reproducible obligations and idempotent external payments. The answer covers event deduplication, period closure, payout versions, timeout ambiguity, outbox delivery, provider reconciliation, late adjustments, and auditable financial state.
System DesignTechnical Screen - CommureHardSoftware EngineerFilter People by Optional Criteria
Implement stable filtering for person records across optional inclusive age and salary bounds plus an optional occupation set. Every enabled criterion must match, disabled bounds use None, and neither the input list nor its records may be mutated.
Coding & AlgorithmsTechnical Screen - CommureMediumSoftware EngineerPresent Your Background and Respond to an AI-Use Concern
This exercise evaluates your ability to provide a structured professional narrative, demonstrate technical depth through project ownership, and maintain poise when confronted with a challenging, ethical, or unexpected behavioral probe.
Behavioral & LeadershipTechnical ScreenBehavioralCommunicationEthics - ComposioMediumSoftware EngineerGenerate a Semantic Dependency Graph from Tool Schemas
Design an algorithm to construct an explainable dependency graph between API tools by matching output and input schemas and identifying unresolved requirements.
Software Engineering FundamentalsOnline AssessmentGraph AlgorithmsData ProcessingSchema Matching - Concentric AiMediumSoftware EngineerCount Students Outside Their Height-Sorted Positions
This problem tests your ability to compare a given array with its sorted version to identify indices where values do not match, assessing your proficiency in sorting and array indexing.
Coding & AlgorithmsOnline AssessmentArraysSortingImplementation - Concentric AiMediumSoftware EngineerMaximize Profit Under a Bitwise-OR Limit
Find a subset of items whose cumulative bitwise OR does not exceed a given limit such that the total profit is maximized.
Coding & AlgorithmsOnline Assessmentbit-manipulationgreedyarrays - Concentric AiMediumSoftware EngineerMinimize Population-Weighted Manhattan Travel Cost
This problem tests the ability to optimize a weighted distance metric by leveraging the independent nature of x and y coordinates in Manhattan geometry.
Coding & AlgorithmsOnline AssessmentArraysSortingMath - ConfluentMediumSoftware EngineerAnswer standard behavioral prompts
This set of behavioral prompts evaluates ownership, leadership, communication, judgment, accountability, resilience, and time-management competencies for software engineers.
Behavioral & LeadershipTechnical Screen - ConfluentMediumSoftware EngineerCheck Whether a Partially Filled 9x9 Sudoku Board Is Valid
A coding problem that asks whether a partially filled 9x9 Sudoku board is consistent, meaning no row, column or 3x3 box repeats a digit among its filled cells. It tests careful bookkeeping of row, column and box membership without attempting to solve the puzzle.
Coding & AlgorithmsOnsite - ConfluentMediumSoftware EngineerDesign RSS Feed and Temporary Mail
This question tests the ability to design a dual-purpose system that handles high-throughput asynchronous feed ingestion and transient, short-lived email alias management.
System DesignOnsiteDistributed SystemsCachingMessage Queues - ConfluentMediumSoftware EngineerDesign a News Feed and Mail Service
This question evaluates a candidate's proficiency in large-scale system design, including distributed ingestion and deduplication, content ranking, API design choices (REST versus RPC), pagination and caching strategies, and techniques for generating and ensuring uniqueness of human-looking disposable email addresses.
System DesignOnsite - ConfluentMediumSoftware EngineerDesign a Podcast Publishing System That Delivers New Episodes to Followers
A system design question about a podcast platform where creators publish episodes and followers see them in a feed. It covers the upload and processing path for audio, building each listener's feed of new episodes, and serving shows whose audiences range from a handful of listeners to millions.
System DesignOnsite - ConfluentHardSoftware EngineerDesign a distributed key-value store at scale
Design a distributed key-value store at scale 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 DesignTechnical Screen - ConfluentHardSoftware EngineerDesign a temporary email service
This question evaluates a candidate's ability to design scalable, highly available, and privacy-focused email ingestion systems, probing competencies in distributed systems, networking (SMTP/MX), storage lifecycle management, rate limiting, security/privacy, and observability.
System DesignTechnical Screen - ConfluentMediumSoftware EngineerDesign an LRU Cache with a Constant-Time Average
Design a fixed-capacity LRU cache whose get, put, and current-value average operations all run in expected constant time. Reason through map and recency-list invariants, running-sum updates, replacement and eviction edge cases, numeric precision, overflow, and tests that catch aggregate or ordering bugs.
Software Engineering FundamentalsOnsite - ConfluentMediumSoftware EngineerDesign an RSS News Feed Service
This question evaluates a candidate's ability to design a scalable RSS news feed service, emphasizing system architecture, relational schema and API design, including database table and index planning, ingestion and serving paths, deduplication/idempotency, and feed generation trade-offs.
System DesignOnsite - ConfluentMediumData ScientistDetermine Tutorial Completion Rate by Variant in 7 Days
This question evaluates a candidate's competency in data manipulation and event-based analytics, focusing on skills such as joining user and event tables, aggregating event data, and computing cohort completion metrics by variant.
Data Manipulation (SQL/Python)Onsite - ConfluentMediumSoftware EngineerDocument Search: Exact Word Match, Non-Adjacent Phrase Match and AND/OR Queries
A progressive coding round that builds search over a collection of documents. It starts with exact whole-word lookup, extends to multi-word queries whose words need not be adjacent, and ends with words combined by AND and OR, testing inverted indexes, set operations and clarifying ambiguous query semantics.
Software Engineering FundamentalsOnsite - ConfluentMediumData ScientistEvaluate Metrics and Randomization for Onboarding Tutorial Change
Evaluate Metrics and Randomization for Onboarding Tutorial Change evaluates metric design, causal reasoning, experiment setup, diagnostics, SQL/statistical checks, and recommendations in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Analytics & ExperimentationOnsite - ConfluentMediumSoftware EngineerExplain Linux Command Execution, Filesystems, and Isolation
Explain what Linux does from shell parsing through process creation, exec, waiting, and exit status, then trace paths, permissions, file descriptors, directories, procfs, and network inspection. Compare containers and virtual machines through their actual isolation boundaries and operational trade-offs.
Software Engineering FundamentalsOnsite - ConfluentHardSoftware EngineerExplain variadic functions
Explain variadic functions evaluates requirements, assumptions, structured reasoning, trade-offs, and verification in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Software Engineering FundamentalsTechnical Screen - ConfluentMediumSoftware EngineerImplement File Tail and Sensor Health
This problem tests your ability to efficiently read the end of a growing file using file pointers and to implement a sliding time-window check for sensor heartbeat events.
Coding & AlgorithmsOnsiteI/OHash MapStreaming - ConfluentMediumSoftware EngineerImplement Tail and Find Monster Cost
This question evaluates competency in efficient file I/O and streaming techniques for implementing tail, and in graph search and shortest-path algorithms with path reconstruction for computing minimum monster cost in a grid.
Coding & AlgorithmsOnsite - ConfluentMediumSoftware EngineerImplement tail -n for a Very Large File
Implement the core of tail -n for a seekable file that may be many gigabytes without scanning it all when the requested suffix is small. Work through backward block reads, chunk boundaries, trailing-newline semantics, bounded memory, binary-versus-text handling, safe decoding, and mutation assumptions.
Software Engineering FundamentalsOnsite - ConfluentMediumSoftware EngineerImplement tail N lines
Confluent software-engineer technical-screen coding question: implement tail(path, N) to print the last N lines of a possibly multi-GB file or an unbounded stream without loading it into memory. It tests a backward block scan for seekable files versus an O(N) ring buffer for non-seekable streams, plus correct handling of \n/\r\n/\r newlines, UTF-8 multibyte characters, missing trailing newlines, and extremely long lines, with follow-ups on tail -f, log rotation/truncation, and the -c last-N-bytes option.
Coding & AlgorithmsTechnical Screen - ConfluentMediumSoftware EngineerMachine Coding: Word Search and Ordered Phrase Search Across a List of Documents
A machine-coding exercise that asks you to build a search component over a list of text documents, first finding the documents that contain a given word and then those where a phrase's words appear in the same sequence. It tests tokenization choices, index design, and handling of repeated words and edge cases.
Software Engineering FundamentalsOnsite - ConfluentMediumSoftware EngineerMatch Argument Type Lists Against Function Signatures with Variadic Parameters
A coding problem about resolving function calls: given a library of function signatures, some variadic in their last parameter, return every function that accepts each queried list of argument types. It tests precise matching rules, indexing signatures for many queries and deterministic output ordering.
Coding & AlgorithmsOnsite
Coinbase
Confluent