Databricks

A recruiter call, an algorithmic coding screen and a hiring manager call, then an onsite of about five one-hour rounds that includes a concurrency round candidates find hardest, followed by references and a hiring committee.

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  Recruiter screen: motivation, background and logisticsBehavioralA short first call with a recruiter: a few standard behavioral questions about your background and why you want the role, then timeline, location and compensation expectations…

  Last asked Sep 2026Were you asked this too?
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  Generalized tic-tac-toe with k in a rowCodingDesign a two-player Tic-Tac-Toe game on a board with n rows and m columns. A player wins by placing k of their own marks consecutively in one line: horizontal, vertical, diagonal…

  Last asked Sep 2026Were you asked this too?
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  Customer revenue with referral credit and bottom-k queryCodingBuild an in-memory system that tracks how much revenue each customer brings in, including revenue from the customers they referred. Customers get integer ids starting at 0, in the…

  Last asked Sep 2026Were you asked this too?
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  Design a Slack-like chat systemSystem designWorkspaces, channels, threads and direct messages with real-time delivery, unread state, search and history, for large companies.

  Last asked Sep 2026Were you asked this too?
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  Design typeahead suggestionsSystem designSuggest completions as the user types into a search box, within tens of milliseconds, ranked by popularity and fresh with trending queries.

  Last asked Sep 2026Were you asked this too?
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  Design a book price aggregatorSystem designShow the current price of a book across many online sellers, keeping prices fresh while respecting each seller's API limits.

  Last asked Sep 2026Were you asked this too?
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  Durable event log writer shared by thousands of threadsCodingMany threads on one server append small opaque records to a single durable log. Design and partly build the writer: how callers hand off records, how writes are batched and…

  Last asked Sep 2026Were you asked this too?
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  Fastest single-mode commute on a city gridCodingYou are planning a commute across a city drawn as a 2D grid of characters: - 'S': your starting point (exactly one). - 'D': your destination (exactly one). - '1' to 'k': a block…

  Last asked Sep 2026Were you asked this too?
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  Key-value store that reports its recent request rateCodingBuild an in-memory key-value store with put and get (delete optional). It must also report how many puts and gets per second it served over a recent stretch of time, say five…

  Last asked Sep 2026Were you asked this too?
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  Ordered IP firewall with CIDR rulesCodingImplement an IPv4 firewall that checks addresses against an ordered list of rules. Each rule is a pair (action, target). action is "ALLOW" or "DENY". target is either a single…

  Last asked Sep 2026Were you asked this too?
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  Build your story bankBehavioralPrepare 8 to 15 real stories, each tagged with the signals it shows (ownership, conflict, failure, ambiguity, influence, impact, mentorship, quality), so that any behavioral…

  Last asked Sep 2026Were you asked this too?
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  Design a single-node in-memory cache with a write-ahead logSystem designDesign an in-memory key-value cache that sits inside one web service. Then make it survive restarts with a write-ahead log, and explain how you would shard it and cut lock…

  Last asked Sep 2026Were you asked this too?
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  Minimum-cost encryption of a directory treeCodingA storage service keeps a filesystem as a tree: Compliance requires every file in the tree to end up encrypted. You can issue two kinds of calls: - encrypt(filepath)

  Last asked Sep 2026Were you asked this too?
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  Path between two nodes of an implicit Fibonacci treeCodingA Fibonacci tree of order k is a binary tree defined recursively: - Orders 0 and 1 are a single node. - For k = 2, the root's left subtree is a Fibonacci tree of order k - 2 and…

  Last asked Sep 2026Were you asked this too?
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  Snapshot set with frozen insertion-order iteratorsCodingImplement SnapshotSet, a set of integers whose iterators are frozen at the moment they are created. - add(value) - bool: insert value. Return False and do nothing if it is already…

  Last asked Sep 2026Were you asked this too?
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  Design a harmful content detection systemML designDetect harmful posts (hate, violence, self-harm, spam) across text and images, with high recall on severe harms and a path to human review.

  Last asked Sep 2026Were you asked this too?
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  First position of any anagram of a pattern in a stringCodingReturn the smallest index at which some rearrangement of a query string appears as a contiguous substring of a text, or -1. Keep a running character count over a fixed-size window…

  Last asked Sep 2026Were you asked this too?
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  Linear regression with hand-written gradient descentCodingFit a one-feature linear regression by gradient descent on mean squared error, without an ML library. Then discuss choosing the learning rate, when to stop, and how to spot a…

  Last asked Sep 2026Were you asked this too?
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  Retrieve tables and notebooks for a data-aware coding agentAI systemAn internal coding agent helps employees write code and answer questions. When someone asks a data question, such as how a metric changed over some period, the agent first has to…

  Last asked Sep 2026Were you asked this too?
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  Design a payment systemSystem designAccept card payments for merchants: authorize, capture, settle with card networks, and reconcile, never charging twice or losing money.

  Last asked Sep 2026Were you asked this too?
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  Design the metadata service of a strongly consistent distributed file systemSystem designDesign the namespace layer for a distributed file system: make directories, list them, put and get files, delete, and walk the tree recursively. A listing must reflect every write…

  Last asked Sep 2026Were you asked this too?
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  Rewrite a SQL query plan treeCodingA query plan is a tree of scan, filter, project and join nodes. Write rewrite rules that make it cheaper, such as moving a filter beneath a join, while the new plan still returns…

  Last asked Sep 2026Were you asked this too?
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  Design retrieval for a coding agent over a code baseAI systemA coding agent is an LLM assistant that works inside a software code base: it reads code, answers questions about it and makes edits. It depends on retrieval to put the right code…

  Last asked Sep 2026Were you asked this too?
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  Primary and secondary circuit breakers with failoverCodingA service reads from a primary backend and can fail over to a secondary backend (for example a leader database and a follower). Put a circuit breaker in front of each backend so…

  Last asked Aug 2026Were you asked this too?
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  Hybrid run-length and bit-packing codecCodingDesign an encoder and a decoder for a list of non-negative integers. The encoder compresses the list into a list of human-readable run strings. The decoder restores the original…

  Last asked Aug 2026Were you asked this too?
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  Remove one point from a cover of integer intervalsCodingYou are given a list of non-overlapping half-open intervals. An interval start, end with start < end covers the integers start, start + 1, ..., end - 1. Reading the intervals in…

  Last asked Aug 2026Were you asked this too?
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  Order service whose database write succeeds but queue publish failsSystem designDesign the order path of an online bookstore. When an order request arrives, the service inserts the order into its database and then publishes a message to a queue (Amazon SQS)…

  Last asked Aug 2026Were you asked this too?
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  Design a collaboratively edited playlistSystem designSeveral people add, remove and reorder songs in the same playlist at once. Scale is not the point: model the ordered list so reorders are cheap and concurrent edits resolve…

  Last asked Jul 2026Were you asked this too?
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  Build a target string from the fewest substrings of a sourceCodingExpress a target string as a concatenation of substrings of a source string, each given by its index range, using as few pieces as possible. Follow-up: after one character of the…

  Last asked May 2026Were you asked this too?
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  Project deep dive: present a project you ledBehavioralPresent a project you led in about 20 minutes: context, your role, the architecture, three hard trade-offs, metrics, cost and return, and what you would change. Then take 25…

  Last asked May 2026Were you asked this too?
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  Uniformly random spanning tree over node groupsCodingYou are given groups, a list of K disjoint, non-empty lists of integer node IDs. Nodes inside a group are already connected to each other; different groups are not connected. You…

  Last asked May 2026Were you asked this too?
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  Lazy array with deferred map and indexOfCodingImplement LazyArray, an integer array that supports deferred mapping. Calls to map are recorded but do not run. The recorded functions run only when a query needs a value…

  Last asked Apr 2026Were you asked this too?
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  Design an order relay service in front of a broker APISystem designClients send buy and sell orders with a deadline to your service, which forwards them to a third-party broker, tracks each order until it fills, and cancels whatever has not…

  Last asked Apr 2026Were you asked this too?
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  Autocomplete data fetching with debounce, retry and cachingCodingThe UI of an autocomplete box is already built; you write only the data-fetching logic behind it. Debounce requests while the user types, retry requests that fail, show only the…

  Last asked Apr 2026Were you asked this too?
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  Design a distributed job schedulerSystem designDesign a service that runs millions of scheduled and on-demand jobs (cron-like and one-off) reliably across a fleet of workers.

  Last asked Apr 2026Were you asked this too?
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  Shortest run-length encoding after deleting k charactersCodingRun-length encoding writes each run of a repeated character as the character followed by the run length when the run is longer than one, so "aaabcc" becomes "a3bc2". Given a…

  Last asked Feb 2026Were you asked this too?
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  Design CRUD APIs backed by asynchronous jobsSystem designDesign a service that exposes create, read, update and delete APIs for a resource, where some operations start long-running work that cannot finish inside the request. Cover the…

  Last asked Jan 2026Were you asked this too?
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  IP range to CIDR blocksCodingGiven a starting IPv4 address and a count n, return the shortest list of CIDR blocks that covers exactly the n consecutive addresses starting there, and no address outside that…

  Last asked Jan 2026Were you asked this too?
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  Design a dependency-aware job schedulerSystem designDesign a job scheduler in which each job is a list of tasks with dependencies between them; a task may start only when every task it depends on has finished. Cover how you…

  Last asked Jan 2026Were you asked this too?
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  Design a digital game store backendSystem designDesign the backend of an online store that sells digital games: players browse a catalog, buy games, and own them afterwards. Focus on the purchase: taking the payment, granting…

  Last asked Dec 2025Were you asked this too?
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  Largest all-ones square and rectangle in a binary matrixCodingGiven a grid of 0s and 1s, return the area of the largest square made only of 1s. Then extend your approach to the largest all-ones rectangle.

  Last asked Nov 2025Were you asked this too?
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  Design a rate limiterSystem designDesign a service that limits how many requests each API client can make. It sits in front of every API endpoint at high traffic.

  Last asked Nov 2025Were you asked this too?
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  Maximum sum of non-adjacent houses, on a line, a circle and a treeCodingEach house holds some value and you cannot take two neighbours. Find the best total for houses in a row, then for houses arranged in a circle, then for houses arranged as a binary…

  Last asked Nov 2025Were you asked this too?
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  Design an ad marketplace between publishers and advertisersSystem designPublishers' pages request ads and advertisers bid to fill them. Design the marketplace: bidding and matching within a tight latency budget, serving the winning ad, and tracking…

  Last asked Nov 2025Were you asked this too?
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  Thread-safe single-machine chat server with channelsCodingBuild an in-process chat system where many clients join channels and post messages that the other members receive. Make it correct under concurrent senders and receivers, and…

  Last asked Oct 2025Were you asked this too?
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  Design UberSystem designRiders request trips, nearby drivers get matched, and both see live location until drop-off, with pricing and payment, for millions of trips a day.

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  Concurrent caching client for byte-range file readsSystem designDesign a client that reads byte ranges of remote files and caches what it has fetched, so a later read of a range it already holds is served locally. Many threads use one client…

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  Diagnose a data pipeline's quality and performance problemsBehavioralAsked in a hiring-manager conversation for a solutions architect role: how do you diagnose a data pipeline whose output has quality problems, or whose runs have become slow? Walk…

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  Design a distributed web crawlerSystem designCrawl billions of web pages politely and repeatedly, deduplicating URLs and content, to feed a search index or a training-data pipeline.

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  Design a GPU scheduling platformAI systemShare a large GPU cluster among research and production teams: queue training and inference jobs, enforce quotas and priorities, place jobs on topology-aware hardware, and preempt…

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  Design a Kafka-like distributed message queueSystem designDesign a durable, partitioned log that producers append to and many consumer groups read at their own pace, surviving broker failures without losing acknowledged messages.

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  Design a RAG system over company docsAI systemEmployees should be able to ask questions about internal documents (Drive, Confluence, Slack, GitHub) and get grounded answers with citations.

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  Design a stock trading platformSystem designUsers place market and limit orders; match them, update balances and positions exactly once, and stream prices in real time.

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  Design a VM bandwidth rate limiterSystem designCap the network bandwidth each virtual machine in a cloud region may use, enforcing per-tenant limits across many hosts without adding latency to packets.

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  Design an S3-like object storage systemSystem designStore trillions of objects of any size with eleven nines of durability, and serve reads and writes over an HTTP API at high throughput.

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  Design DropboxSystem designSync files across a user's devices and shared folders: upload large files reliably, transfer only what changed, and handle conflicting edits.

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  Drop a Tetris piece and clear full rowsCodingImplement a single step of a Tetris-like game. You get three inputs: - background: an H x W grid of 0/1. 1 is an occupied cell, 0 is empty. Row 0 is the top. - block: an h x w…

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  Find bottleneck dependencies in a parallel buildCodingYou are given n build targets numbered 0 to n - 1 and a list of directed edges edges. An edge u, v means target v cannot start building until target u has finished. The graph has…

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