Stripe

A recruiter call, a coding screen in a real project editor, then an onsite of four or five rounds: one or two practical coding sessions (fixing bugs, integrating an API, building on a skeleton), a payments-flavored system design, a hiring-manager conversation and a values round. References are checked closely before an offer.

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  Fix planted bugs in an open-source library from its failing testsCodingYou get a checkout of a real open-source library (a template engine, an HTTP client or a parser) with a few bugs planted in it. Run the test suite, follow the failures into code…

  Last asked Oct 2026Were you asked this too?
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  Split-tender payments with gift cards, surcharges and refundsCodingAt a retail point of sale one purchase can be paid with several methods, for example part on a gift card and the rest on a credit card (a split-tender transaction). Write the code…

  Last asked Oct 2026Were you asked this too?
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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 Oct 2026Were you asked this too?
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  Merchant onboarding CSV validatorCodingMerchants submit their business details as rows of a simple CSV. Before a merchant can accept payments, every row must pass a set of checks. Write validaterecords(data…

  Last asked Oct 2026Were you asked this too?
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  Build a transaction rule engine with an AI assistantCodingWith an AI coding assistant built into the editor, implement a rule engine that reads allow and block conditions and applies them to a list of transactions. You are graded on how…

  Last asked Oct 2026Were you asked this too?
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  Design a feature flag serviceSystem designLet teams turn features on for a percentage of users or specific accounts, with changes reaching every service within seconds and no per-request network call.

  Last asked Oct 2026Were you asked this too?
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  Route requests to the nearest healthy data centerCodingBuild a router that processes commands: register a data center with its latitude, longitude and capacity, mark data centers up or down, report the great-circle distance between…

  Last asked Sep 2026Were you asked this too?
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  Rebuild a task tree from parent-child records and print itCodingYou get a list of task records, each naming a task and its parent. Rebuild the hierarchy of tasks and subtasks and print it as a text tree with connector characters, in the exact…

  Last asked Sep 2026Were you asked this too?
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  Draw routes on map images fetched from an HTTP APICodingRead a JSON file of places and routes, call a remote map service to download the matching map images, then mark the places and draw lines between them on the images. The task…

  Last asked Sep 2026Were you asked this too?
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  Match payments to invoices by memo and amountCodingA billing system has to match incoming payments to open invoices. Both arrive as comma-separated strings. - Invoice: invoiceid,amount,duedate. The amount is an integer in cents…

  Last asked Sep 2026Were you asked this too?
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  Monthly AI token billing with plan switchingCodingYou are building the monthly invoice step for a chat-based AI product that charges by token usage. Each chat session produces one record, given as a comma-separated string with…

  Last asked Sep 2026Were you asked this too?
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  Deployment windows in a recurring weekCodingDeployments are planned on a recurring week measured in minutes, from 0 to 10,079, and the same schedule repeats every week. Teams declare windows in which deployment is allowed…

  Last asked Sep 2026Were you asked this too?
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  Hiring-manager round on impact and collaborationBehavioralA behavioral round on past project impact, work with non-engineering partners, mentorship, and roadmap influence. Distinct from the values-focused culture round.

  Last asked Sep 2026Were you asked this too?
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  Hotel stay email schedule with booking changesCodingA hotel wants to send each guest a set of emails around their stay. Write the code that produces the full email schedule. Input - reservations: a list of objects with guestname…

  Last asked Sep 2026Were you asked this too?
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  Financial account ledger with acceptance, limits and settlementCodingImplement processledger(commands), which handles commands in order: set up accounts, request deposits and query balances. Return the query answers as one comma-separated string…

  Last asked Sep 2026Were you asked this too?
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  Iterating on a product after shipping its MVPBehavioralHave you built a minimum viable product and then had to keep improving it? Walk through it: how you scoped the first version, what you learned once people used it, how you decided…

  Last asked Sep 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 Sep 2026Were you asked this too?
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  Reconcile bank account balances across two datasetsCoding1. From a list of balance records for bank accounts, return the latest balance of an account, in the output format the tests expect. 2. A second dataset is added. Reconcile the…

  Last asked Aug 2026Were you asked this too?
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  Design a payments ledgerSystem designDesign the double-entry ledger behind a payments API: money movements must never be lost or applied twice.

  Last asked Aug 2026Were you asked this too?
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  Design an idempotent double-entry ledger serviceSystem designDesign a ledger service that records money movements for merchants as double-entry transactions and answers balance and history queries. Cover the data model, making writes…

  Last asked Aug 2026Were you asked this too?
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  Design a metrics monitoring systemSystem designCollect metrics from every host and service, store them as time series, power dashboards over months of data, and alert when thresholds are crossed.

  Last asked Aug 2026Were you asked this too?
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  Payment command parser and state machineCodingBuild the parser and the object-oriented state machine behind a payment command interface. Every command line has the same fixed number of positions, with empty strings in the…

  Last asked Aug 2026Were you asked this too?
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  Build a React interface against an undocumented APICodingWith an AI coding assistant available, build a React interface on top of an API that has no documentation. Work out the endpoints and the shape of their data by exploring them…

  Last asked Jun 2026Were you asked this too?
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  Estimate and break down an ambiguous projectBehavioralDescribe a project that started out vague. How did you break it into pieces and estimate it, how close did the estimate come, and what did you do when it slipped? A good answer…

  Last asked Jun 2026Were you asked this too?
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  Design a superhero dispatch systemSystem designDesign a system that sends superheroes to incidents across a city. An incident is reported with its location; the system finds an available hero nearby, assigns them and tracks…

  Last asked May 2026Were you asked this too?
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  Design a payment fraud detection systemML designScore every card payment for fraud within tens of milliseconds, balancing blocked fraud against declined good customers, with labels that arrive weeks later.

  Last asked May 2026Were you asked this too?
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  Account balances from a transaction logCodingA payments system receives a log of transactions and must turn it into account statements. Each log entry is a string with four comma-separated fields: - transactionid: a unique…

  Last asked May 2026Were you asked this too?
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  Assign code reviewers from the files changed between branchesCodingWrite a program that compares two branches of a Git repository (the reported version used the JGit library in Java), collects the files that changed, and assigns reviewers using a…

  Last asked Apr 2026Were you asked this too?
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  Multitask regression with targets on different scalesML designAn ML coding exercise that follows a fraud-detection design discussion. Instead of a classification label, the model has two regression targets: one takes only negative values…

  Last asked Apr 2026Were you asked this too?
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  Factory network cost with stage-to-stage transportCodingA company is planning a chain of factories. Each factory has several candidate options, and you must pick exactly one option for every factory. The interview comes in parts; each…

  Last asked Apr 2026Were you asked this too?
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  Transaction fees from a CSV of paymentsCodingYou get payment transactions as a CSV string. Compute the fee for each one and the total fees per user. The rate depends on the payment type and provider and on the transaction's…

  Last asked Apr 2026Were you asked this too?
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  Inner join of two CSV datasetsCodingTwo systems export CSV data that you need to combine. Implement: Each dataset is a list of lines. The first line is a header of comma-separated column names. Every other line is a…

  Last asked Apr 2026Were you asked this too?
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  Render, compress and invert a bitmap fontCodingA bitmap font is given as strings of 0 and 1 bits, one bitmap per character. 1. Render each character as a grid of text, with . for a 0 bit and another character for a 1 bit. 2…

  Last asked Feb 2026Were you asked this too?
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  Sticky load balancer for long-lived connectionsCodingSimulate a load balancer that routes long-lived WebSocket connections to several Jupyter servers. Process a sequence of requests such as CONNECT, DISCONNECT and SHUTDOWN: place…

  Last asked Feb 2026Were you asked this too?
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  Cheapest flights within K stopsCodingGiven flights as (from, to, price), a source, a destination and an integer k, return the cheapest price from the source to the destination using at most k stops, or -1 if there is…

  Last asked Feb 2026Were you asked this too?
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  Settle group debts with the fewest transfersCodingA group of people owe each other money, given as transfers (from, to, amount). Return the smallest number of transfers that brings every person's balance to zero.

  Last asked Feb 2026Were you asked this too?
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  Card authorization report with fraud rulesCodingA payment platform receives authorization requests: a card holder's intent to pay a merchant. Write a function that decides each request and returns a report. Each request is a…

  Last asked Jan 2026Were you asked this too?
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  Shipping cost with tiered pricingCodingAn order names a country and the products and quantities in it, and a pricing table gives the shipping cost of each product for each country. 1. Compute the order's total shipping…

  Last asked Jan 2026Were you asked this too?
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  Alert trigger and resolve events from merchant error logsCodingYou get transaction logs with timestamp, merchantid, statuscode and count. For each (merchantid, statuscode) pair, emit a TRIGGER event when that error's count over a recent time…

  Last asked Jan 2026Were you asked this too?
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  Free 30-minute time slotsCodingGiven the busy intervals in a day, return every available 30-minute slot.

  Last asked Jan 2026Were you asked this too?
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  Link similar user records by weighted field matchesCodingA data-quality team wants to find user profiles that probably belong to the same person. You get records, a 2D list of strings. The first row is a header of field names, and one…

  Last asked Jan 2026Were you asked this too?
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  Resolve user roles across an account hierarchyCodingAccounts form a hierarchy, and users are given roles on accounts. Given the hierarchy and the role assignments, work out the roles a user has on a given account, including roles…

  Last asked Jan 2026Were you asked this too?
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  Least-loaded task assignment with worker specialtiesCodingTasks arrive in a fixed order and must be handed out to a team of workers so that the work stays balanced. Each task has a unique integer id, a positive integer duration, and (in…

  Last asked Jan 2026Were you asked this too?
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  Design a webhook delivery systemSystem designDeliver event notifications to customers' HTTP endpoints at least once, with retries and backoff, signing, ordering where it matters, and isolation from slow endpoints.

  Last asked Dec 2025Were you asked this too?
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  Account scheduler with locking and LRU selectionCodingBuild a scheduler that hands out accounts from a pool to callers. An account that is handed out is locked until it is released, and when several accounts are free the scheduler…

  Last asked Dec 2025Were you asked this too?
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  Sliding-window request rate limiterCodingImplement a rate limiter that accepts at most limit requests in any window of ttl milliseconds. - allow(timestamp) is called once per incoming request. timestamp is in…

  Last asked Dec 2025Were you asked this too?
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  Design an account takeover detection systemML designSpot logins and account changes made by someone other than the owner, scoring each event in real time and choosing to allow, challenge or block.

  Last asked Oct 2025Were you asked this too?
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  Card number validation with the Luhn checkCodingImplement a payment-card validator. Check a card number with the Luhn checksum and work out its network from its prefix and length. Later parts recover card numbers with missing…

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  Best currency conversion rate across exchange quotesCodingYou run a currency desk. You are given a list of quotes (from, to, rate): one unit of from buys rate units of to. A quote works only in the direction given; the reverse is…

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  Multi-step form in ReactCodingBuild a three-step form: step 1 collects the user's basic details, step 2 their address, and step 3 shows everything for confirmation and submits. Support validation on each step…

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  Searchable transaction list that highlights the largestCodingBuild a small interface in three steps: 1. Render a list of transactions given as {name: string, amount: number}. 2. Highlight the name of the transaction with the largest amount…

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  Passport number form with per-country formatsCodingYou get a map from country to passport number format, for example {USA: "LLDDDD", Canada: "AALLDDDD"}, where L must be a letter, D a digit and A either one. 1. Build the layout: a…

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  Cloud usage bill from regional hourly ratesCodingYou are writing the billing step for a cloud platform. A customer's usage report says which region they ran in and how many hours they used each service. A pricing table gives the…

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  Design a customer churn prediction systemML designPredict which business customers will stop using the product in the next 30 days, so account teams can act in time.

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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.

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  Design a merchant lending systemSystem designOffer business loans to merchants based on their payment history, then repay automatically by withholding a share of each day's sales.

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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.

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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.

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  Design an access management systemSystem designDecide who can do what to which resource across many services: roles, groups, fine-grained permissions, fast checks on every request, and auditable changes.

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  Match applicant skills and versions to a job's requirementsCodingAn applicant tracking system screens candidates by the skills they list. Each applicant gives one comma-separated string of skills, strongest first. A job posting gives a…

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  Server load scores from a day of requestsCodingA load balancer team wants a daily stress report for its server fleet. You get three inputs for one day: - servers: lines serverid,basescore. Every server starts at its integer…

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  Shipping route cost pathsCodingA parcel carrier publishes its shipping routes as a list of strings. Each string has the form source:target:method:cost: - source and target are country codes. A route ships one…

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  Tell me about a time you disagreed with your teamBehavioralDescribe a real disagreement about a technical decision: what was at stake, what you did, and how it ended.

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