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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.
- 9403
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- 546
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- 11
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- 8
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Showing 2701–2730 of 9403 results
- DatabricksHardSoftware EngineerDesign a Hierarchical File System
This question tests the ability to design a distributed file system namespace capable of handling millions of files and directories with strong consistency and high availability.
System DesignOnsiteDistributed SystemsMetadataScalability - DatabricksHardSoftware EngineerDesign a KV store with QPS API
This question tests the ability to design a distributed key-value store architecture that incorporates observability, specifically tracking per-key or per-prefix Queries Per Second (QPS) metrics in real-time.
System DesignTechnical ScreenDistributed SystemsObservabilityCaching - DatabricksHardSoftware EngineerDesign a Key-Value Store with Hit Counting
Design a concurrent, in-memory key-value store that tracks read-access frequency using a sliding-window hit counter per key while keeping memory footprint bounded.
Software Engineering FundamentalsOnsiteconcurrencysliding-windowsystem-design - DatabricksMediumSoftware EngineerDesign a Shared, Crash-Safe Telemetry Buffer for Thousands of Worker Threads
Design a single, thread-shared component that lets up to 4,000 worker threads inside one process append small telemetry records to one local file, durably and without a disk sync per call. Tests group-commit concurrency design, a crash-safe on-disk record format, and backpressure reasoning.
System DesignOnsiteconcurrencydurabilitysystem-design - DatabricksMediumSoftware EngineerDesign a Slack-Like Messaging System
Tests your ability to architect a scalable, real-time messaging platform like Slack, focusing on connection handling, fan-out delivery, channel message ordering, and presence management.
System DesignOnsiteDistributed SystemsWebSocketsPub/Sub - DatabricksMediumSoftware EngineerDesign a Thread-Safe Buffered Writer with a Background Flush Thread
Tests the ability to design a high-throughput, thread-safe buffering system that decouples client write operations from high-latency storage I/O using concurrent synchronization, backpressure, and background worker threads.
System DesignOnsiteConcurrencyMultithreadingI/O - DatabricksMediumSoftware EngineerDesign a Visa-Style Card Payment Processing System
Design a Visa-style card payment system, choosing between the card network and a merchant-side scope. Tests real-time authorization routing to issuers, idempotent handling of retries and reversals, clearing and settlement with an auditable ledger, fraud checks, and multi-region availability.
System DesignOnsite - DatabricksHardSoftware EngineerDesign a Visa-like payment processing system
This problem tests your ability to design a high-throughput, fault-tolerant transaction processing system that guarantees data integrity across distributed services.
System DesignTechnical ScreenDistributed SystemsConsistencyPayments - DatabricksHardSoftware EngineerDesign a Write-Ahead Log Writer with Batch Writes
Design and implement a concurrent write-ahead log (WAL) engine featuring group commit, monotonic sequence assignment, torn-tail crash recovery, and explicit durability promises.
Software Engineering FundamentalsOnsitestorage-enginesconcurrencysystems-programming - DatabricksHardSoftware EngineerDesign a digital game shop backend
This question tests your ability to design a distributed, fault-tolerant transaction processing system for a digital storefront, focusing on data consistency and concurrency control.
System DesignOnsiteDistributed SystemsConcurrencyDatabase - DatabricksMediumSoftware EngineerDesign a generic key-value store
This question evaluates a software engineer's ability to design a clean, type-safe API for a generic key-value store, covering data modeling, interface design, and extensibility. It tests practical software design skills including generics, error handling, concurrency, and the ability to evolve an in-memory prototype into a persistent implementation without breaking callers.
System DesignTechnical Screen - DatabricksHardSoftware EngineerDesign a key-value store
This question evaluates understanding of durable storage and crash-consistency, including on-disk data layout, filesystem durability semantics, concurrency control, and performance trade-offs for single-node embeddable key–value engines.
System DesignOnsite - DatabricksMediumSoftware EngineerDesign a multithreaded event logger
This problem tests your ability to design a thread-safe, high-throughput logging system that balances memory efficiency with I/O performance under concurrent load.
Software Engineering FundamentalsOnsiteConcurrencyMultithreadingDesign Patterns - DatabricksMediumSoftware EngineerDesign a rolling event tracker with ranges
This question evaluates understanding of time-series data structures and streaming counters, testing algorithm design, space/time complexity analysis, correctness across edge cases, and handling of large-scale event tracking.
Coding & AlgorithmsTechnical Screen - DatabricksHardSoftware EngineerDesign a single-node persistent in-memory cache
This question evaluates a candidate's skills in single-node cache design, including in-memory key/value storage, eviction policy management (e.g., LRU), durability considerations, concurrency control, and techniques for reducing contention such as sharding or striping.
System DesignTechnical Screen - DatabricksMediumSoftware EngineerDesign a stock order manager
Design an equity Order Management System (OMS) that manages order lifecycles, ensures idempotent broker interactions, and guarantees state reconciliation under distributed failures.
System DesignTechnical Screensystem-designdistributed-systemsfintech - DatabricksHardSoftware EngineerDesign a thread-safe bounded queue
This question evaluates skills in concurrent programming, synchronization primitives, and designing thread-safe bounded data structures that support blocking operations with timeouts, fairness, and backpressure.
System DesignHR Screen - DatabricksMediumSoftware EngineerDesign an IP filter using CIDR rules
This question evaluates understanding of IP addressing and CIDR notation, bit-level conversion between prefixes and integer ranges, and the design of scalable data structures and algorithms for prefix/range queries, rule priority handling, and rule-set operations (allow/deny semantics).
Coding & AlgorithmsTechnical Screen - DatabricksMediumSoftware EngineerDesign an Online Book Seller Platform
Design an end-to-end e-commerce platform for selling books, balancing read-heavy catalog exploration with strictly consistent inventory reservation and fault-tolerant checkout workflows.
System DesignOnsiteE-CommerceDistributed SystemsTransactions - DatabricksHardSoftware EngineerDesign an Online Bookstore
This problem tests your ability to design a distributed e-commerce platform by focusing on consistency models for inventory, scalable search architecture, and robust order processing.
System DesignOnsiteMicroservicesDistributed SystemsConsistency - DatabricksMediumSoftware EngineerDesign an efficient Tic-Tac-Toe engine
This question evaluates a candidate's understanding of efficient algorithm design and minimal state management for a Tic-Tac-Toe engine on an n x n board, including constraints such as O(1) time per move and O(n) space.
Coding & AlgorithmsOnsite - DatabricksMediumSoftware EngineerDesign an n x n Tic-Tac-Toe Game
This problem tests your ability to design an efficient class to manage game state, focusing on constant-time win condition checking using auxiliary data structures.
Coding & AlgorithmsOnsiteObject-Oriented DesignData StructuresOptimization - DatabricksMediumSoftware EngineerDesign an online bookstore: DB insert succeeds but SQS publish fails, and duplicate messages
System design question about an online bookstore whose order service inserts orders into a database and then publishes messages to Amazon SQS. Probes what should happen when the insert succeeds but the publish fails, how to keep the database and queue consistent across crashes, and how consumers avoid duplicate processing under at-least-once delivery.
System DesignTechnical Screen - DatabricksMediumSoftware EngineerDesign bookstore and chat messaging systems
This question tests the ability to design two distinct systems: a reliable transactional e-commerce inventory service and a low-latency real-time chat application, focusing on appropriate database choices and communication protocols.
System DesignOnsiteDistributed SystemsDatabasesReal-time - DatabricksHardSoftware EngineerDesign concurrent range-aware file caching client
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 concurrent range-aware file caching client states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
System DesignHR Screen - DatabricksMediumMachine Learning EngineerDetect Harmful Content in LLM Prompts and Responses
Design a machine learning system that detects harmful content in prompts sent to, and responses produced by, a large language model. Tests policy-driven framing, labeling and adversarial data, layered classifiers under latency limits, per-category evaluation, streaming checks and monitoring.
ML System DesignOnsite - DatabricksMediumSoftware EngineerDetect a K-in-a-Row Win on a Rectangular Board
Implement an efficient win-detection function that checks whether a newly placed token forms at least k consecutive matching tokens along any linear axis on a rectangular grid.
Coding & AlgorithmsOnsiteArraysMatrixGame Theory - DatabricksHardSoftware EngineerDetermine allow/deny for an IP via CIDR rules
This problem tests your ability to efficiently manage and query hierarchical IP address ranges, requiring knowledge of bitwise operations and data structures for range matching.
Coding & AlgorithmsTechnical ScreenBit ManipulationTrieNetworking - DatabricksMediumData EngineerDiagnose data quality and pipeline performance issues
Diagnose data quality and pipeline performance issues 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 & LeadershipTechnical Screen - DatabricksHardSoftware EngineerDiscuss Motivation, Feedback, and Technical Disagreement
This interview module evaluates engineering motivation, individual technical ownership, constructive receipt of critical feedback, and principled conflict resolution during technical disagreements.
Behavioral & LeadershipOnsiteBehavioralLeadershipConflict Resolution
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