Software Engineer System Design Interview Questions
Practice 1,082 real System Design interview questions for Software Engineer roles. From companies including Meta, OpenAI, Amazon, Anthropic, Google.
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Design delayed job scheduler (LLD)
Design a Delayed Job Scheduler (Low-Level Design) Design a service that schedules a job to execute X seconds in the future with second-level accuracy....
Design cart management lifecycle service
Scenario You are designing the backend for an on-demand delivery app (restaurants and grocery). Users can create a cart, modify items from multiple de...
Design a thread-safe bounded queue
Design a Thread-Safe Bounded MPMC Queue with Timeouts and Fairness Context You are building a reusable, in-memory, bounded queue that supports multipl...
Determine identical files ignoring metadata
Question How would you determine whether two files contain identical bytes while ignoring all filesystem metadata? Propose and justify a hashing-based...
Design a supermarket checkout system
Design the software for a supermarket checkout system. A grocery store has multiple checkout lanes operated by cashiers, and the design should also be...
Design in-memory database API
Design an In-Memory Database: Insert, Query, and Indexing Design and implement a minimal, single-process, in-memory database intended to be embedded i...
Design in-memory DB with TTL and backup
Question Design and implement an in-memory, versioned key → (field → value) database that supports per-field TTL, time-travel reads, lexicographically...
Design a Multi-Provider Financial Dashboard
Design a financial dashboard that shows account balances, stock holdings, cryptocurrency holdings, and derived portfolio metrics. Data arrives from mu...
Design a Merchant Ledger Service
This question evaluates system design skills related to modeling monetary values, transactional integrity, idempotency, auditability, concurrency cont...
Design a High-Availability Load Balancer
This question evaluates knowledge of distributed systems and load balancing principles, covering high-availability architecture for HTTP/HTTPS traffic...
Design a user behavior monitoring system
System Design: User Behavior Monitoring System You are asked to design a monitoring/analytics system that collects user behavior events from clients (...
Design cloud storage system
Design cloud storage system In-Memory Cloud Storage: Design and Implement You are asked to design and implement an in-memory cloud storage system that...
Design product catalog service
Design product catalog service Design a product catalog service for a large e-commerce / grocery platform. The catalog must support a hierarchical cat...
Design a Global Calendar Service
Design a calendar system for users in multiple time zones. The system should support: - creating, updating, deleting, and viewing calendar events - on...
Design Internal Chat and Re-engagement Emails
Design an internal chat system for an event marketplace company. Requirements: - Employees can send and receive one-to-one messages in real time. - Cl...
Design paginated list UI and pagination API
Scenario You are building a web page that displays a list of items (e.g., posts, products, or users). The list must be paginated, and users can click ...
Design a distributed tree node counter
Design a distributed tree node counter Distributed Tree Node Count with Two Messages You are given an N-ary tree of machines (one process per node). E...
How Would You Optimize a Program
You are given an existing program that produces correct results but is too slow in production. Describe a structured plan to optimize it. Your answer ...
Design authorization and audit logging systems
This question evaluates competency in designing secure authorization and audit logging systems, including access-control models (RBAC/ABAC/hybrid), po...
Design an encrypted log collection system
This question evaluates competence in distributed systems design, secure transport and storage, encryption and key management, scalability, and observ...