Coinbase Software Engineer Onsite Coding Questions

### Generate Random NFT You need to generate a random NFT dataset. Each NFT is uniquely identified by a string and there are no duplicates. Given an integer n, return a list of n unique NFTs. **Inpu

I felt I tried very hard in the interview but still failed. Maybe I wasn't good enough. I interviewed with the Finhub team. BQ Round: Standard behavioral questions. They asked three questions: conflic

This post was last edited by Anonymous on 2025-9-30 14:56 The following content requires a score higher than 100. You can already view it. Coding 1: Log Filter I didn't finish answering the 3 question

The OA interview experience is here: https://www.1point3acres.com/bbs/thread-1145841-1-1.html The VO interview was with the FinHub team under the platform, a total of 4 rounds, spread over 2 days. Bot

Exactly the same as: https://leetcode.com/discuss/interview-question/1198505/Coinbase-or-Onsite-or-SWE-Reject A way for users to buy and sell stocks match buyers with the lowest seler (<= buyer\'s price) match sellers with the highest buyer (>= seller\'s price) But instead...

LeetCode #528: Random Pick with Weight. Difficulty: Medium. Topics: Array, Math, Binary Search, Prefix Sum, Randomized. Asked at Coinbase in the last 6 months.

LeetCode #588: Design In-Memory File System. Difficulty: Hard. Topics: Hash Table, String, Design, Trie, Sorting. Asked at Coinbase in the last 6 months.

## Problem: Banking System Coding Exercise (Multi-Currency + History Replay Follow-ups) The post mentions a "banking system" problem with follow-ups for multiple currency types and history replay, bu

## Problem: NFT Coding Exercise (Implement Core NFT Operations + Write Tests) The post only states it is an "NFT" problem and that you must write your own tests, but it does not specify required oper

You are given a set of transactions (or blocks) to include in a block. Each transaction has: - `id` - `fee` - `size` - dependencies: some transactions have a parent; selecting a transaction requires s

Implement a jump-boundary / collision-detection function for a Flappy Bird–like game. Given: - The bird’s current position and velocity (or position only) - Obstacles (pipes) with their positions and

## Problem: In-Memory DB Variant — Add User-based locking You are implementing a simplified **in-memory database** storing `key -> record`. This variant introduces **users** and a **lock** mechanism

## Problem: In-Memory DB Variant — Track per-key operation counts and return Top N keys You are implementing a simplified **in-memory database** that stores data as `key -> record`. In this variant,

## Problem: Flappy-Bird-like Autopilot With Coins as Jump Budget You are given a simplified side-scrolling jumping game. You must implement a **policy** that decides whether to `jump` at each time st

## Drone Food Delivery: Simulate “Nearest Forward Station” and Compute Total Distance You need to simulate a drone delivery system that moves a package from position `0` to `target`. All positions li

## Problem You are generating NFT metadata. You are given `K` attribute categories (e.g., `Ears`, `Eyes`, `Hat`), each with a list of candidate values. ### Part A: Generate all combinations Generate

## Problem You are given `N` log lines (strings). Each line follows the format: ``` <timestamp> <thread_id> <level> <message> ``` - `timestamp`: an ISO-8601 time string, e.g. `2024-01-01T10:00:00Z`

Implement an API that supports filtering and pagination. The API should return a data collection based on filter criteria and paginate the results by specified page number and items per page.

Given a collection of items, design a pagination function that displays `k` items per page, and return the list of items on the `n`th page. Assume there may be multiple pagination criteria, you need t

Design and implement a function to perform block mining on a given set of transactions. Each transaction has a unique ID and other necessary attributes. Implement two functionalities: one for independ