Stripe Coding Interview Questions

A multi-part integration task set in a real GitHub repository (cloned locally). Candidates work through 3–5 sequential sub-problems, each building on the…

Given an order object (containing a destination country and a list of items with product name and quantity) and a shipping cost…

Implement a subscription email notification system. You are given two primary inputs: 1. send_schedule (dict/map): Maps event keys to email subject/title strings.…

You are given a cloned repository of a modified version of the Mako Python template engine. The repository contains several pre-planted bugs.…

You are given a single multi-line string representing a CSV dataset. Each row contains 6 comma-separated columns: col1, col2, col3, col4, col5,…

You are given a payment record (as a comma-separated string, e.g. 'payment-id, amount, memo/paying-off-text [, invoice-id]') and a list of invoice records…

You are given a list of transactions in CSV format with columns: account_name, timestamp, currency, amount. Each row represents a credit (positive…

You are given a bitmap lookup table (a dictionary/map) where each key is a character (e.g., 'J') and the value is a…

You are given a list of merchant records, where each merchant is a dict/object with fields: id, name, email, phone (some variants…

Implement a rule parser/engine that evaluates a list of decision rules against input transaction data to determine whether a transaction should be…

Implement a function route_requests(numTargets, maxConnectionsPerTarget, requests) that simulates a load balancer for a notebook platform running multiple Jupyter target servers. Targets are…

You are given a CSV-formatted string representing a list of payment transactions. Each row contains fields such as: id, reference, amount, currency,…

A multi-part integration problem (typically 3–5 parts) in which the candidate must write code against a real, provided codebase to perform payment/invoice…

Build a simplified request routing system for a globally distributed cloud service provider (e.g., a global payment processing platform). The system processes…

Given a sequence of API requests stored in a JSON log file, replay each request and validate that the actual HTTP responses…

You are given a repository implementing a custom HTTP requests library (similar in spirit to Python's requests). Two test cases are failing,…

You are given an unfamiliar open-source YAML parsing library (SnakeYAML in Java/Python, or yaml-cpp in C++) with one or more failing tests.…

Candidates are given a real-world JSON parsing library codebase (most commonly Moshi or Jackson-core, in Java) and a set of failing test…

Given a list of time-sorted transaction log entries, each containing a timestamp, merchant_id, status_code (error code), and count, design an incident monitoring…

Design a risk scoring system that computes a final risk score for each merchant based on a list of transactions, a parallel…

You are given a 3D array where each row (first dimension) represents a production step (or factory type), and each element within…

You are given a card data string where the first two digits encode the length of the following field, which contains an…

You are given a list of input strings, each representing a shipping route in the format '{source}:{target}:{method}:{cost}' (e.g., 'US:UK:UPS:10'). Implement a series…

Given a list of user API usage records — each containing a user ID, input token count, output token count, and a…

Implement a function joinDataSet(fieldName, customerFile, processorFile, skipUnmatched) that merges two CSV-like datasets. Inputs: - fieldName (String): the column name to join on…

You are given a string of currency exchange rate pairs, e.g., "AUD:USD:0.7,AUD:JPY:100,USD:CAD:1.2" (or equivalently pairs like a:b=1:1.5, b:c=1:1.5). The problem is delivered…

You are given two inputs: (1) a list of worker names, and (2) a list of tasks, where each task is a…

Build a frontend form UI component for passport number validation. You are given a country-format object (e.g., { USA: "LLDDDD", Canada: "AALLDDDD"…

You are given a list of unordered CSV records describing tasks and subtasks. Each record has the format: <timestamp>,task,<task_id>,<task_name> <timestamp>,subtask,<subtask_id>,<parent_id>,<task_name> Example input:…

Given a tabular dataset (e.g., transaction records with fields like id, date, card type, amount), open a Jupyter notebook and use the…

Implement a multi-part payment card validation system using the Luhn algorithm for Stripe. Card Networks: - VISA: 16 digits, starts with 4…

You are given a weekly timeline of 10080 minutes (minute 0 = Monday 00:00, minute 10079 = Sunday 23:59). All intervals are…

You are given a web-based VS Code environment (or similar IDE with debugger support) and a Python ML codebase with three planted…

You are given an array of transaction objects with the shape { name: string, amount: number }[]. Implement a frontend UI in…

A multi-part coding problem involving contact matching and consolidation using email domains. Input must be read from stdin. Part 1: Given a…

A 60-minute coding interview (≈45 min coding) structured as four sequential, unlockable parts simulating a fraud-detection pipeline that reads transaction data from…

You are given two data structures: 1. accounts: a list of dicts, each with accountId (string) and parent (string or None), forming…

Given a string with hierarchical delimiters — '/' separates major parts and '.' separates minor parts — compress each segment by keeping…

Given a user's preferred language list and a system's supported language list, implement a series of progressively more complex matching functions: Part…

Implement an AccountScheduler class that manages a set of accounts and their availability based on locked_until timestamps. Inputs: - accounts: a list…

Given a stream of card transaction records, each containing fields: id, date, card_type, and amount — produce output records with the same…

You are given a list of payments to process, each with a specified currency and amount, along with a balance map showing…

You are given a list of user accounts in a credit card company's system (each account has some balance or outstanding amount)…

Stripe accepts payments on behalf of merchants. Payments begin as Authorization Requests representing an intent to transfer funds from a user's credit…

Given a real dataset, implement an end-to-end ML solution for two regression tasks simultaneously. Key challenge: one task has negative label values…

Given an arbitrary date-time range [start_date, end_date] and a weekly recurring working_hours configuration table (mapping each day-of-week to its working start/end times),…

A multi-part coding problem (P1, P2, P3) involving stores and time-based penalties. Each part builds on the previous with increasing difficulty. The…

Design a rate limiter that supports two operations: 1. hit(key, timestamp) — Record one access by a given key (e.g., an API…

HackerRank-based online assessment (no webcam required) for a Stripe PhD New Grad MLE role, consisting of three parts: (1) Several multiple-choice questions…

Given a 6-digit BIN (Bank Identification Number) string and an array of card number range strings, produce a complete sorted list of…

A multi-part fraud detection problem. The prompt was posted only as images, which are not recorded; the parts below are reconstructed from…

A multi-part command-parsing OA problem simulating a payment system. You are given a sequence of commands that must be parsed and executed…

Given a collection of JSON objects (conceptually imported from CSV data), complete a 3-part coding test within 60 minutes. Part 1: From…

Given a set of entities/merchants, each with shared attributes, group them into clusters where two entities belong to the same cluster if…

Given a Git repository, use JGit to compare two branches and extract the list of files that changed between them. Then, cross-reference…

Given a tabular dataset of shape ~(thousands of rows) × (tens of columns), implement a neural network (using PyTorch or a similar…

Given a set of customer transaction data tables containing numerical features, categorical (string) features, randomly generated features, and missing values, build a…

Given a repository implementing a failsafe/retry policy library (candidates are told they can Google the open-source 'failsafe' library for context), identify and…

Given a simplified/modified fork of the Preact repository (a lightweight React-like frontend framework), identify and fix a bug within the codebase. The…

A bug-squash coding round conducted in Ruby using the RSpec testing framework. Stripe takes the open-source RSpec library as a baseline and…