Software Engineering Fundamentals Interview Questions
Practice the exact questions companies are asking right now.
Explain KV cache in Transformer inference
Question In Transformer-based language model inference, what is a key-value (KV) cache? Explain: - What gets cached (tensors, shapes at a high level) ...
Generate a ride map image via POST API
You are given a local JSON file ride-simple.json containing a recorded bike ride as an ordered list of GPS points. Assume the file format is: `json { ...
Explain container image flow in CI/CD
Scenario Walk through what happens in a typical CI/CD pipeline that builds and deploys a containerized service. Questions 1. During CI, how is a conta...
Explain virtual machines and concurrency basics
Topics Answer at a senior-engineer depth. Use diagrams or step-by-step reasoning as needed. 1) Virtual machines (VMs) - What is a VM and what problem ...
Explain how to understand a large codebase fast
You are given an unfamiliar, large codebase with many classes and modules. You may use an IDE (jump-to-definition, find usages, call hierarchy) and AI...
Write SQL for top spender and non-spenders
SQL Questions Assume the following schema: - users(user_id, created_at, ...) - transactions(txn_id, user_id, amount, txn_ts) - amount is a positive ...
Design a social network with snapshots
You are asked to design and implement an in-memory SocialNetwork class that supports users following each other and creating snapshots of the follow g...
Design CSV upload endpoint with GPT classification
You are building a backend service that needs to process two CSV files and then call an external GPT-like API for classification. Requirements 1. HTTP...
Explain how to make robust HTTP API calls
SWE Fundamentals: Making Robust HTTP Calls (Client/Service) You need to integrate with an external HTTP API (could be an internal microservice or a th...
Design a multithreaded event logger
Design a multithreaded in-memory event logger for a server application. Requirements: - Many worker threads running in the process need to log events ...
Debug a slow concurrent network server under load
Scenario You are on-call for a high-throughput network service (e.g., a TCP/HTTP server). Under load, users report: - Throughput suddenly drops - p99 ...
Fix race condition in concurrent deposit
Concurrent bank account debugging (thread safety) You are given a simple BankAccount object that is used concurrently from multiple threads. Two depos...
Design an object-oriented poker game
Design the object-oriented architecture for a command-line poker game. Requirements (clarify and state assumptions) Assume a standard 52-card deck (no...
Explain Runnable vs Callable and thread-safe Singleton
Concurrency & Design Patterns (Java) 1. In Java concurrency, what is the difference between Runnable and Callable? - When would you choose one over...
Explain inheritance, polymorphism, constructors, destructors
OOP fundamentals Answer the following concept questions and provide a small example where requested: 1. Inheritance vs. polymorphism - Explain what...
Optimize a core kernel for throughput
You are given a mocked “core kernel” function (similar in spirit to a GPU kernel / tight compute loop) that is functionally correct but slow. Task - O...
Debug and harden a driver-selection component
Debugging Exercise: “Pick Dasher” You are given a small codebase for selecting a dasher (driver) using a heap/priority-queue–like structure. The curre...
Design a jigsaw puzzle (OOD)
Object-Oriented Design: Jigsaw Puzzle Design an object-oriented model for a jigsaw puzzle game. Requirements - The puzzle consists of a set of pieces ...
Design article voting and flip-tracking system
Design an object-oriented "Article System" that supports voting and query operations. You need to design the data model and core APIs (including metho...
Choose lock granularity for concurrent storage
You are implementing a component inside a storage engine that is accessed concurrently (e.g., an in-memory index, metadata cache, or block map). Discu...