Question bank.
Every question from the company pages, merged: the most-reported first. Each one links the lessons that teach it and the companies it comes from.
353 questions · ● reported with a source · ○ likely, from their products
- Design a URL ShortenerSystem design · reported at 16● Amazon● Apple● Freshworks● Intuit● JioHotstar● MakeMyTrip● Microsoft● Morgan Stanley● Nykaa● Oracle● Postman● Salesforce● ShareChat● Sprinklr● Urban Company● Walmart Global TechIP-01 · Design a URL Shortener →W01 · BOSS · Design a URL Shortener at Scale →IP-04 · Design a Unique ID Generator →
- Design a Parking LotLow-level design · reported at 13● Amazon● Freshworks● Goldman Sachs● MakeMyTrip● Microsoft● Morgan Stanley● Nykaa● PayPal● Razorpay● Salesforce● Swiggy● Uber● ZohoLLD-01 · Design a Parking Lot →
- Design a Rate LimiterSystem design · reported at 9● Freshworks● Google○ Juspay● LinkedIn● Microsoft● Nykaa● Ola● Oracle● Paytm○ Stripe○ Zerodha● ZomatoIP-02 · Design a Rate Limiter →W01 · DAY 03 · Rate Limiting at Scale →W09 · DAY 05 · Security Architecture →
- Design a News FeedSystem design · reported at 9● Goldman Sachs○ LinkedIn● Meta● Microsoft● PhonePe● Postman● ShareChat● Stripe● Swiggy● Walmart Global TechIP-07 · Design a News Feed →SQ-10 · Twitter/X →W04 · DAY 04 · Feed Caching →
- Design a Distributed Job SchedulerSystem design · reported at 9● Amazon● Atlassian● LinkedIn● Microsoft● Netflix● PhonePe● Postman● Razorpay● SwiggyIP-17 · Design a Distributed Job Scheduler →W02 · DAY 05 · Distributed Cron & Job Scheduling →W05 · DAY 05 · Leader Election and Coordination →
- Design SplitwiseLow-level design · reported at 9● Amazon● Groww● MakeMyTrip● Meesho● Nykaa● PhonePe● Razorpay● ShareChat● SwiggyLLD-06 · Design a Bill-Splitting App (Splitwise) →
- Design a Notification SystemSystem design · reported at 8● Amazon○ Apple○ Atlassian○ CRED● Goldman Sachs● Groww○ Intuit○ LinkedIn○ Meesho● Myntra○ Netflix● Ola● Oracle● Razorpay● ZomatoIP-06 · Design a Notification System →W06 · DAY 01 · Notification Platform — Problem Understanding & High-Level Design →W06 · DAY 02 · Core Notification Flow →
- Design a File Sync ServiceSystem design · reported at 6○ Adobe● Amazon○ Apple● CRED○ Google● JPMorgan Chase● Microsoft● Nykaa● OracleIP-10 · Design a File Sync Service (Dropbox / Google Drive) →SQ-08 · AWS S3 →W05 · DAY 04 · Conflict Resolution →
- Design an Elevator SystemLow-level design · reported at 6● Adobe● Apple● MakeMyTrip● Microsoft● PayPal● SprinklrLLD-04 · Design an Elevator System →
- Design a Payment SystemSystem design · reported at 5● Goldman Sachs○ Intuit○ JPMorgan Chase○ Juspay● Microsoft● Myntra● PayPal○ Paytm○ PhonePe○ Razorpay● ShareChat○ Stripe○ UberIP-20 · Design a Payment System →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →W05 · DAY 01 · Consistency Models →
- Design a Chat SystemSystem design · reported at 5● Amazon● Freshworks● JioHotstar● Meta○ Microsoft○ ShareChat● UberIP-08 · Design a Chat System →SQ-02 · WhatsApp Messaging →
- Design a Ride-Hailing ServiceSystem design · reported at 5● Amazon● CRED● Freshworks● MakeMyTrip○ Ola○ Rapido● UberSQ-09 · Uber →IP-13 · Design a Proximity Service →W01 · DAY 04 · Hot Keys and Skew →
- Design a Web CrawlerSystem design · reported at 5● Atlassian● Freshworks● InMobi● Meta● MicrosoftIP-05 · Design a Web Crawler →W02 · DAY 05 · Distributed Cron & Job Scheduling →W03 · DAY 01 · Queue vs Stream →
- Design an In-Memory Message QueueLow-level design · reported at 5● Adobe● Intuit● Microsoft● Salesforce● UberLLD-08 · Design a Logging Framework (Pub-Sub) →IP-18 · Design a Distributed Message Queue →
- Design an LRU CacheLow-level design · reported at 5● MakeMyTrip● Microsoft● Paytm● Rapido● SprinklrLLD-02 · Design an LRU Cache →IP-11 · Design a Distributed Cache →
- Design Snake and LadderLow-level design · reported at 5● Goldman Sachs● Meesho● Salesforce● Swiggy● Walmart Global Tech
- Design a Real-Time LeaderboardSystem design · reported at 4● Apple● Dream11● Groww● MakeMyTrip○ MetaIP-14 · Design a Real-Time Leaderboard →W01 · DAY 04 · Hot Keys and Skew →
- Design a Ticket Booking SystemSystem design · reported at 4● Flipkart● Morgan Stanley● Paytm● Zoho○ ZomatoSQ-16 · BookMyShow Seat Booking →LLD-05 · Design a Movie Ticket Booking System →SQ-11 · IRCTC Tatkal Ticket Booking System →
- Design a Chess GameLow-level design · reported at 4● Adobe● Apple● Sprinklr● Urban Company
- Design a Logging SystemSystem design · reported at 4● Apple● Freshworks● Google● Walmart Global TechW08 · DAY 01 · Event Ingestion at Scale →W08 · DAY 05 · Query Layer and Optimization →W10 · DAY 02 · Observability →
- Design a Rate Limiter (LLD)Low-level design · reported at 4● Atlassian● PayPal● Postman● RazorpayLLD-03 · Design a Rate Limiter →IP-02 · Design a Rate Limiter →W01 · DAY 03 · Rate Limiting at Scale →
- Design a Vending MachineLow-level design · reported at 4● Amazon● Goldman Sachs● Meesho● Urban CompanyLLD-07 · Design a Vending Machine →
- Design an In-Memory File SystemLow-level design · reported at 4● PayPal● Salesforce● Sprinklr● Zoho
- Design a Food Delivery SystemSystem design · reported at 3● Freshworks● JioHotstar● Ola○ Swiggy○ Uber○ ZomatoSQ-17 · Swiggy Food Delivery →W06 · BOSS · Food Delivery Order System →W03 · BOSS · Event-Driven Food Delivery Order System →
- Design a Video Streaming ServiceSystem design · reported at 3○ Google● Meta○ Netflix● Ola● Oracle○ ShareChatSQ-19 · YouTube Video Platform →SQ-06 · Netflix Streaming →W04 · DAY 05 · Multi-Tier Caching →
- Design a Metrics Monitoring and Alerting SystemSystem design · reported at 3● Dream11● LinkedIn○ Netflix● StripeIP-15 · Design a Metrics Monitoring and Alerting System →W10 · DAY 02 · Observability →W08 · DAY 03 · Data Modeling for Analytics →
- Design a cab booking systemLow-level design · reported at 3● Meesho● Razorpay● SwiggySQ-09 · Uber →IP-13 · Design a Proximity Service →
- Design a Car Rental SystemLow-level design · reported at 3● Adobe● Flipkart● Walmart Global TechLLD-05 · Design a Movie Ticket Booking System →IP-19 · Design a Hotel Reservation System →LLD-01 · Design a Parking Lot →
- Design a Logging FrameworkLow-level design · reported at 3● Morgan Stanley● Razorpay● UberLLD-08 · Design a Logging Framework (Pub-Sub) →
- Design a Movie Ticket Booking System (LLD)Low-level design · reported at 3● JioHotstar● PayPal● Urban CompanyLLD-05 · Design a Movie Ticket Booking System →SQ-16 · BookMyShow Seat Booking →
- Design a Collaborative EditorSystem design · reported at 2○ Adobe○ Atlassian○ Google○ Microsoft● Postman● RazorpaySQ-15 · Figma Multiplayer Editing →SQ-20 · Google Docs Collaboration →W05 · DAY 04 · Conflict Resolution →
- Design a Proximity ServiceSystem design · reported at 2○ Google● Meta○ Ola○ Rapido● Uber○ ZomatoIP-13 · Design a Proximity Service →W01 · DAY 01 · Partitioning Deep-Dive →W01 · DAY 04 · Hot Keys and Skew →
- Design a Stock Exchange / Trading PlatformSystem design · reported at 2● Dream11● InMobi○ Morgan Stanley○ ZerodhaSQ-13 · Zerodha Kite Trading Platform →W05 · DAY 05 · Leader Election and Coordination →W05 · DAY 01 · Consistency Models →
- Design Webhook DeliverySystem design · reported at 2○ Atlassian● Stripe● UberW02 · DAY 04 · Webhook Delivery System →W03 · DAY 04 · Dead Letters and Poison Pills →W02 · DAY 02 · Idempotency in Practice →
- Design a Circuit Breaker (LLD)Low-level design · reported at 2● PayPal● ShareChatW02 · DAY 03 · Circuit Breakers →
- Design a Distributed Message QueueSystem design · reported at 2● Apple● LinkedInIP-18 · Design a Distributed Message Queue →W03 · DAY 01 · Queue vs Stream →W02 · DAY 02 · Idempotency in Practice →
- Design a Doctor Appointment Booking SystemLow-level design · reported at 2● Intuit● SalesforceLLD-05 · Design a Movie Ticket Booking System →IP-19 · Design a Hotel Reservation System →
- Design a Leaderboard (LLD)Low-level design · reported at 2● Intuit● UberIP-14 · Design a Real-Time Leaderboard →
- Design a Library Management SystemLow-level design · reported at 2● Walmart Global Tech● Zoho
- Design a Ludo gameLow-level design · reported at 2● ShareChat● Urban Company
- Design a News Summary App (Inshorts)System design · reported at 2● Goldman Sachs● GoogleIP-07 · Design a News Feed →W04 · DAY 04 · Feed Caching →IP-05 · Design a Web Crawler →
- Design a Snake GameLow-level design · reported at 2● Atlassian● Zomato
- Design a Stock Exchange / Trading PlatformLow-level design · reported at 2● Goldman Sachs● JioHotstarSQ-13 · Zerodha Kite Trading Platform →
- Design a stock exchange order bookLow-level design · reported at 2● Groww● MeeshoSQ-13 · Zerodha Kite Trading Platform →
- Design a Tagging SystemSystem design · reported at 2● Atlassian● SalesforceW09 · DAY 01 · Tenant Isolation Strategies →W07 · DAY 02 · Indexing Pipeline →W01 · DAY 04 · Hot Keys and Skew →
- Design an Image Hosting ServiceSystem design · reported at 2● Google● IntuitSQ-08 · AWS S3 →W04 · DAY 05 · Multi-Tier Caching →SQ-21 · Instagram Feed and Stories →
- Design an IoT Sensor Data PlatformSystem design · reported at 2● Amazon● AppleW08 · DAY 01 · Event Ingestion at Scale →IP-15 · Design a Metrics Monitoring and Alerting System →W03 · DAY 03 · Backpressure and Flow Control →
- Design an Order Management SystemSystem design · reported at 2● Goldman Sachs● Walmart Global TechW03 · BOSS · Event-Driven Food Delivery Order System →W05 · DAY 03 · Saga Orchestration Deep Dive →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →
- Design InstagramSystem design · reported at 2● Oracle● PhonePeSQ-21 · Instagram Feed and Stories →IP-07 · Design a News Feed →
- Design Instagram StoriesSystem design · reported at 2● Goldman Sachs● MetaSQ-21 · Instagram Feed and Stories →W04 · DAY 05 · Multi-Tier Caching →
- Design TwitterSystem design · reported at 2● InMobi● SprinklrSQ-10 · Twitter/X →IP-07 · Design a News Feed →
- Design a Digital WalletSystem design · reported at 1● Dream11○ PayPal○ Paytm○ StripeIP-20 · Design a Payment System →W02 · DAY 02 · Idempotency in Practice →SQ-01 · India's UPI →
- Design Typeahead Search (Autocomplete)System design · reported at 1○ Google○ LinkedIn● Microsoft○ MyntraIP-09 · Design Typeahead Search (Autocomplete) →W07 · DAY 04 · Advanced Search Features →
- Design a Cab Booking App (LLD)Low-level design · reported at 1○ Rapido● Urban CompanySQ-09 · Uber →
- Design a Distributed CacheSystem design · reported at 1● Google○ NetflixIP-11 · Design a Distributed Cache →W04 · DAY 01 · Caching Patterns →W01 · DAY 04 · Hot Keys and Skew →
- Break a Monolithic Shopping App into MicroservicesSystem design · reported at 1● JPMorgan ChaseW03 · BOSS · Event-Driven Food Delivery Order System →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →W03 · DAY 02 · Transactional Outbox →
- Build a Friends Online-Status Service (Machine Coding)Low-level design · reported at 1● PostmanIP-08 · Design a Chat System →W01 · DAY 05 · Session Store Design →
- Build a Real-Time Log Watcher like tail -f (Machine Coding)Low-level design · reported at 1● BrowserStackW03 · DAY 03 · Backpressure and Flow Control →W00 · PART 4 · Networking Fundamentals for System Design →W00 · PART 5 · Operating System Concepts for System Design →
- Build a Simple Key-Value Store like pickleDBLow-level design · reported at 1● PostmanIP-03 · Design a Distributed Key-Value Store →
- Build a Web Service that Controls Browsers (Machine Coding)Low-level design · reported at 1● BrowserStackW00 · PART 5 · Operating System Concepts for System Design →
- Build an In-Memory Pub-Sub like Kafka (Machine Coding)Low-level design · reported at 1● InMobiLLD-08 · Design a Logging Framework (Pub-Sub) →IP-18 · Design a Distributed Message Queue →
- Compute metrics over a time range from an event logLow-level design · reported at 1● CREDIP-15 · Design a Metrics Monitoring and Alerting System →W08 · DAY 03 · Data Modeling for Analytics →
- Debug a system from its log fileConcept · reported at 1● JuspayW10 · DAY 02 · Observability →W10 · DAY 05 · Incident Management →
- Design a Bingo gameLow-level design · reported at 1● Paytm
- Design a Book-Shelf Service like Goodreads (REST APIs)Low-level design · reported at 1● PayPalW04 · DAY 01 · Caching Patterns →
- Design a booking aggregator for movies and cabsSystem design · reported at 1● GrowwSQ-16 · BookMyShow Seat Booking →W10 · DAY 02 · Observability →
- Design a Browser Automation System without SeleniumLow-level design · reported at 1● BrowserStackW00 · PART 4 · Networking Fundamentals for System Design →
- Design a Buy Now Pay Later (BNPL) systemLow-level design · reported at 1● FlipkartIP-20 · Design a Payment System →W02 · DAY 02 · Idempotency in Practice →
- Design a Cache with Configurable Eviction Policy (LLD)Low-level design · reported at 1● PayPalLLD-02 · Design an LRU Cache →IP-11 · Design a Distributed Cache →
- Design a calendarLow-level design · reported at 1● Myntra
- Design a Calendar App like Google CalendarLow-level design · reported at 1● JioHotstarIP-06 · Design a Notification System →
- Design a Calendar App like Google CalendarSystem design · reported at 1● PayPalIP-06 · Design a Notification System →IP-17 · Design a Distributed Job Scheduler →
- Design a Calendar Invite ServiceSystem design · reported at 1● LinkedInIP-06 · Design a Notification System →IP-19 · Design a Hotel Reservation System →
- Design a Call Taxi Booking Application (LLD)Low-level design · reported at 1● ZohoSQ-09 · Uber →
- Design a Carpool Ride-Sharing App (LLD)Low-level design · reported at 1● Urban CompanySQ-09 · Uber →IP-13 · Design a Proximity Service →
- Design a cart and checkout systemLow-level design · reported at 1● MeeshoW02 · DAY 02 · Idempotency in Practice →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →
- Design a Catalog Event Enrichment PipelineSystem design · reported at 1● LinkedInW08 · DAY 01 · Event Ingestion at Scale →W08 · DAY 02 · Streaming vs Batch Processing →
- Design a chess move validatorLow-level design · reported at 1● Groww
- Design a clinic appointment booking systemLow-level design · reported at 1● MeeshoLLD-05 · Design a Movie Ticket Booking System →IP-19 · Design a Hotel Reservation System →
- Design a Collaborative Coding Pad (CoderPad)System design · reported at 1● LinkedInSQ-20 · Google Docs Collaboration →SQ-15 · Figma Multiplayer Editing →
- Design a Collaborative Document Editor (LLD)Low-level design · reported at 1● AmazonSQ-20 · Google Docs Collaboration →W05 · DAY 04 · Conflict Resolution →
- Design a Concurrent Hash MapLow-level design · reported at 1● Walmart Global TechW00 · PART 5 · Operating System Concepts for System Design →W01 · DAY 01 · Partitioning Deep-Dive →
- Design a conference room booking systemLow-level design · reported at 1● FlipkartLLD-05 · Design a Movie Ticket Booking System →IP-19 · Design a Hotel Reservation System →
- Design a Continue-Watching (Resume Video) FeatureSystem design · reported at 1● JioHotstarSQ-06 · Netflix Streaming →W01 · DAY 05 · Session Store Design →
- Design a coupon service for an e-commerce platformSystem design · reported at 1● ShareChatW04 · DAY 01 · Caching Patterns →W02 · DAY 02 · Idempotency in Practice →
- Design a coupon-based discount systemLow-level design · reported at 1● SwiggyW04 · DAY 01 · Caching Patterns →
- Design a Course Registration SystemSystem design · reported at 1● Goldman SachsSQ-11 · IRCTC Tatkal Ticket Booking System →W01 · DAY 04 · Hot Keys and Skew →
- Design a Customer Loyalty Points ProgramLow-level design · reported at 1● AmazonW02 · DAY 02 · Idempotency in Practice →IP-20 · Design a Payment System →
- Design a Customer Support Chatbot for Hotel and Flight BookingsSystem design · reported at 1● MakeMyTripW03 · BOSS · Event-Driven Food Delivery Order System →W02 · DAY 03 · Circuit Breakers →
- Design a Delayed Task SchedulerLow-level design · reported at 1● LinkedInW02 · DAY 05 · Distributed Cron & Job Scheduling →W00 · PART 5 · Operating System Concepts for System Design →
- Design a delivery-partner payout system with offersLow-level design · reported at 1● SwiggyIP-20 · Design a Payment System →
- Design a Distributed Key-Value StoreSystem design · reported at 1● LinkedInIP-03 · Design a Distributed Key-Value Store →W01 · DAY 01 · Partitioning Deep-Dive →W01 · DAY 02 · Replication Trade-offs →
- Design a Document-Sharing ApplicationSystem design · reported at 1● FreshworksIP-10 · Design a File Sync Service (Dropbox / Google Drive) →SQ-08 · AWS S3 →W09 · DAY 05 · Security Architecture →
- Design a Fantasy Sports Platform like Dream11System design · reported at 1● MakeMyTripIP-14 · Design a Real-Time Leaderboard →W02 · BOSS · The Ultimate System Design Interview →W04 · DAY 03 · Thundering Herd →
- Design a Fast-Food Outlet Ordering System like McDonald's (LLD)Low-level design · reported at 1● Nykaa
- Design a feature of a video-call app like Google MeetSystem design · reported at 1● Myntra
- Design a File Management System (LLD)Low-level design · reported at 1● FreshworksW00 · PART 5 · Operating System Concepts for System Design →
- Design a fitness-centre slot booking app like CultLow-level design · reported at 1● MeeshoLLD-05 · Design a Movie Ticket Booking System →
- Design a flight booking system like MakeMyTripSystem design · reported at 1● CREDIP-19 · Design a Hotel Reservation System →SQ-11 · IRCTC Tatkal Ticket Booking System →
- Design a Food Delivery App (LLD)Low-level design · reported at 1● Morgan StanleySQ-17 · Swiggy Food Delivery →W03 · BOSS · Event-Driven Food Delivery Order System →
- Design a hackathon platform with scoring and recommendationsLow-level design · reported at 1● PhonePeIP-14 · Design a Real-Time Leaderboard →
- Design a home-services marketplace like UrbanClapSystem design · reported at 1● FlipkartIP-13 · Design a Proximity Service →SQ-09 · Uber →
- Design a Hospital Appointment System with Patient Priorities (LLD)Low-level design · reported at 1● InMobi
- Design a Jira-like task management toolLow-level design · reported at 1● Flipkart
- Design a Key-Value Store with TransactionsLow-level design · reported at 1● UberIP-03 · Design a Distributed Key-Value Store →W05 · DAY 01 · Consistency Models →
- Design a Keyword Search FeatureSystem design · reported at 1● MetaW07 · DAY 01 · Search Fundamentals & Architecture →W07 · DAY 02 · Indexing Pipeline →
- Design a ledger to store transactions from many servicesSystem design · reported at 1● FlipkartIP-20 · Design a Payment System →W03 · DAY 05 · Audit Log System →W02 · DAY 02 · Idempotency in Practice →
- Design a live cricket score app like Cricbuzz (LLD)Low-level design · reported at 1● ShareChatW04 · DAY 04 · Feed Caching →
- Design a Live Cricket Score App like Cricbuzz (Schema)Low-level design · reported at 1● OracleW04 · DAY 03 · Thundering Herd →W08 · DAY 03 · Data Modeling for Analytics →
- Design a Live Cricket Score ClientSystem design · reported at 1● AdobeW02 · DAY 01 · Timeout Hell →W04 · DAY 01 · Caching Patterns →W03 · DAY 03 · Backpressure and Flow Control →
- Design a load balancerLow-level design · reported at 1● RazorpayW00 · PART 2 · Infrastructure Building Blocks →W02 · DAY 03 · Circuit Breakers →
- Design a Load BalancerSystem design · reported at 1● MetaW00 · PART 2 · Infrastructure Building Blocks →W00 · PART 4 · Networking Fundamentals for System Design →
- Design a Log Scanner that Raises Tickets on ExceptionsSystem design · reported at 1● OracleW10 · DAY 02 · Observability →W08 · DAY 01 · Event Ingestion at Scale →
- Design a Logger Rate LimiterLow-level design · reported at 1● GoogleLLD-03 · Design a Rate Limiter →LLD-08 · Design a Logging Framework (Pub-Sub) →
- Design a malicious URL detection serviceSystem design · reported at 1● PhonePeIP-11 · Design a Distributed Cache →W04 · DAY 01 · Caching Patterns →
- Design a Meeting Slot RecommenderLow-level design · reported at 1● Salesforce
- Design a Memory Management SystemLow-level design · reported at 1● AdobeW00 · PART 5 · Operating System Concepts for System Design →
- Design a message brokerLow-level design · reported at 1● Dream11IP-18 · Design a Distributed Message Queue →LLD-08 · Design a Logging Framework (Pub-Sub) →
- Design a microprocessor with registersLow-level design · reported at 1● CRED
- Design a Multithreaded Job SchedulerLow-level design · reported at 1● UberIP-17 · Design a Distributed Job Scheduler →W02 · DAY 05 · Distributed Cron & Job Scheduling →
- Design a music streaming service like SpotifySystem design · reported at 1● FlipkartSQ-07 · Spotify →W07 · DAY 01 · Search Fundamentals & Architecture →
- Design a Nested Comments System (Machine Coding)Low-level design · reported at 1● Postman
- Design a News AppSystem design · reported at 1● AppleIP-07 · Design a News Feed →W04 · DAY 04 · Feed Caching →W04 · DAY 05 · Multi-Tier Caching →
- Design a Notification SystemLow-level design · reported at 1● AdobeIP-06 · Design a Notification System →W06 · DAY 02 · Core Notification Flow →
- Design a Package Tracking SystemLow-level design · reported at 1● Walmart Global TechW03 · DAY 05 · Audit Log System →IP-06 · Design a Notification System →
- Design a Page Visit CounterSystem design · reported at 1● IntuitW01 · DAY 04 · Hot Keys and Skew →IP-16 · Design an Ad Click Aggregation System →
- Design a paginated transaction-history APISystem design · reported at 1● ZomatoW08 · DAY 05 · Query Layer and Optimization →W01 · DAY 01 · Partitioning Deep-Dive →
- Design a Parking Finder that Shows Free Spaces NearbySystem design · reported at 1● OracleIP-13 · Design a Proximity Service →LLD-01 · Design a Parking Lot →
- Design a Parking Lot System that Uses an AI Number-Plate CameraSystem design · reported at 1● JPMorgan ChaseLLD-01 · Design a Parking Lot →W02 · DAY 01 · Timeout Hell →W03 · DAY 01 · Queue vs Stream →
- Design a Payment Aggregator that Routes for the Best Success RateLow-level design · reported at 1● Urban CompanySQ-18 · Razorpay Payment Gateway →IP-20 · Design a Payment System →W02 · DAY 03 · Circuit Breakers →
- Design a Payment GatewaySystem design · reported at 1● PayPalSQ-18 · Razorpay Payment Gateway →IP-20 · Design a Payment System →W02 · DAY 04 · Webhook Delivery System →
- Design a payment gateway (machine coding)Low-level design · reported at 1● PhonePeSQ-18 · Razorpay Payment Gateway →IP-20 · Design a Payment System →
- Design a payment-method recommendation systemLow-level design · reported at 1● CREDIP-20 · Design a Payment System →SQ-18 · Razorpay Payment Gateway →
- Design a payments risk management serviceSystem design · reported at 1● PaytmW08 · DAY 02 · Streaming vs Batch Processing →W02 · DAY 01 · Timeout Hell →
- Design a peer-to-peer chess gameSystem design · reported at 1● ZomatoW05 · BOSS · Multiplayer Game Matchmaking System →
- Design a pendency system that counts in-flight entitiesLow-level design · reported at 1● PhonePe
- Design a persistent pub-sub queue with ordered deliveryLow-level design · reported at 1● RazorpayIP-18 · Design a Distributed Message Queue →LLD-08 · Design a Logging Framework (Pub-Sub) →
- Design a phonebook appLow-level design · reported at 1● FlipkartIP-09 · Design Typeahead Search (Autocomplete) →
- Design a pipeline that moves stock candle data from cache to SQLSystem design · reported at 1● GrowwW08 · DAY 02 · Streaming vs Batch Processing →W04 · DAY 01 · Caching Patterns →W08 · DAY 03 · Data Modeling for Analytics →
- Design a Point-of-Sale SystemSystem design · reported at 1● AppleW02 · DAY 02 · Idempotency in Practice →W05 · DAY 04 · Conflict Resolution →
- Design a Popularity CounterLow-level design · reported at 1● Walmart Global TechIP-14 · Design a Real-Time Leaderboard →
- Design a prepaid mini walletLow-level design · reported at 1● PhonePeIP-20 · Design a Payment System →W02 · DAY 02 · Idempotency in Practice →
- Design a Railway Ticket Reservation System (LLD)Low-level design · reported at 1● ZohoSQ-11 · IRCTC Tatkal Ticket Booking System →LLD-05 · Design a Movie Ticket Booking System →
- Design a Real-Time Trending Topics ServiceSystem design · reported at 1● GoogleW08 · DAY 02 · Streaming vs Batch Processing →SQ-10 · Twitter/X →IP-16 · Design an Ad Click Aggregation System →
- Design a Recommendation SystemSystem design · reported at 1● SalesforceW08 · DAY 02 · Streaming vs Batch Processing →W04 · DAY 01 · Caching Patterns →
- Design a Recommendation System for a Streaming AppSystem design · reported at 1● JioHotstarSQ-06 · Netflix Streaming →W08 · DAY 02 · Streaming vs Batch Processing →
- Design a Recommendation System for an Online Book StoreSystem design · reported at 1● OracleW08 · DAY 02 · Streaming vs Batch Processing →
- Design a relational database like MySQLSystem design · reported at 1● FlipkartIP-03 · Design a Distributed Key-Value Store →W01 · DAY 02 · Replication Trade-offs →
- Design a Resource Inventory Service for a Cloud ProviderSystem design · reported at 1● OracleW01 · DAY 01 · Partitioning Deep-Dive →W07 · DAY 01 · Search Fundamentals & Architecture →W09 · DAY 01 · Tenant Isolation Strategies →
- Design a Restaurant Discovery FeedSystem design · reported at 1● UberSQ-17 · Swiggy Food Delivery →IP-13 · Design a Proximity Service →W04 · DAY 04 · Feed Caching →
- Design a Restaurant Reservation SystemLow-level design · reported at 1● Goldman SachsIP-19 · Design a Hotel Reservation System →LLD-05 · Design a Movie Ticket Booking System →
- Design a Reusable Library Shared Across Many ServicesLow-level design · reported at 1● JPMorgan ChaseW02 · DAY 03 · Circuit Breakers →W02 · DAY 01 · Timeout Hell →
- Design a reviews and ratings system with moderationSystem design · reported at 1● MyntraW03 · DAY 01 · Queue vs Stream →W04 · DAY 01 · Caching Patterns →
- Design a Round-Robin Reverse ProxyLow-level design · reported at 1● BrowserStackW00 · PART 2 · Infrastructure Building Blocks →IP-02 · Design a Rate Limiter →
- Design a Rules EngineSystem design · reported at 1● SalesforceW09 · BOSS · Design a Multi-Tenant Enterprise SaaS Platform →W04 · DAY 02 · Invalidation Strategies →
- Design a Scalable Secrets Storage ServiceSystem design · reported at 1● PayPalW09 · DAY 05 · Security Architecture →IP-03 · Design a Distributed Key-Value Store →
- Design a Secrets VaultSystem design · reported at 1● AdobeW09 · DAY 05 · Security Architecture →W09 · DAY 01 · Tenant Isolation Strategies →
- Design a Server-Driven Video Feed for a Mobile AppSystem design · reported at 1● RapidoSQ-19 · YouTube Video Platform →W04 · DAY 04 · Feed Caching →
- Design a service that calls an endpoint at a fixed intervalLow-level design · reported at 1● CREDIP-17 · Design a Distributed Job Scheduler →W02 · DAY 05 · Distributed Cron & Job Scheduling →
- Design a Service That Indexes a Social Network's FeedSystem design · reported at 1● GoogleW07 · DAY 02 · Indexing Pipeline →W07 · DAY 01 · Search Fundamentals & Architecture →SQ-10 · Twitter/X →
- Design a Social Media Site and Its DatabaseSystem design · reported at 1● BrowserStackIP-07 · Design a News Feed →SQ-21 · Instagram Feed and Stories →
- Design a social network like Facebook (LLD)Low-level design · reported at 1● MeeshoIP-07 · Design a News Feed →
- Design a Social Network like Instagram or FacebookSystem design · reported at 1● FreshworksIP-07 · Design a News Feed →SQ-21 · Instagram Feed and Stories →W04 · DAY 04 · Feed Caching →
- Design a song recognition service like ShazamSystem design · reported at 1● PhonePe
- Design a Split-and-Merge Task Processing SystemSystem design · reported at 1● Goldman SachsW08 · DAY 02 · Streaming vs Batch Processing →IP-17 · Design a Distributed Job Scheduler →
- Design a sprint plannerLow-level design · reported at 1● Meesho
- Design a stock market tick-stream system for millions of usersSystem design · reported at 1● PaytmSQ-13 · Zerodha Kite Trading Platform →W08 · DAY 01 · Event Ingestion at Scale →W03 · DAY 03 · Backpressure and Flow Control →
- Design a Stock Price Alert SystemSystem design · reported at 1● UberIP-06 · Design a Notification System →W03 · DAY 01 · Queue vs Stream →W06 · DAY 03 · Advanced Features →
- Design a Subscription and Usage-Based Billing CalculatorLow-level design · reported at 1● StripeW08 · DAY 04 · Late-Arriving Data and Correctness →IP-20 · Design a Payment System →
- Design a subscription management systemSystem design · reported at 1● PhonePeSQ-18 · Razorpay Payment Gateway →IP-17 · Design a Distributed Job Scheduler →
- Design a subscriptions platform for recurring paymentsSystem design · reported at 1● RazorpaySQ-18 · Razorpay Payment Gateway →IP-20 · Design a Payment System →IP-17 · Design a Distributed Job Scheduler →
- Design a Support Ticket-Raising Application (LLD)Low-level design · reported at 1● ZohoW09 · BOSS · Design a Multi-Tenant Enterprise SaaS Platform →
- Design a system that assigns drivers to ordersLow-level design · reported at 1● SwiggySQ-17 · Swiggy Food Delivery →IP-13 · Design a Proximity Service →
- Design a Targeted Marketing Campaign EngineSystem design · reported at 1● NykaaW06 · DAY 01 · Notification Platform — Problem Understanding & High-Level Design →W06 · DAY 03 · Advanced Features →W08 · DAY 02 · Streaming vs Batch Processing →
- Design a Task Manager Application (LLD)Low-level design · reported at 1● Zoho
- Design a Task Manager that Evicts the Least Frequent Tasks (LLD)Low-level design · reported at 1● Urban CompanyLLD-02 · Design an LRU Cache →
- Design a Task Scheduler (LLD)Low-level design · reported at 1● OracleIP-17 · Design a Distributed Job Scheduler →W02 · DAY 05 · Distributed Cron & Job Scheduling →
- Design a task tracker with an activity logLow-level design · reported at 1● PhonePeW03 · DAY 05 · Audit Log System →
- Design a thread-safe lock/unlock treeLow-level design · reported at 1● JuspayW05 · DAY 05 · Leader Election and Coordination →W00 · PART 5 · Operating System Concepts for System Design →
- Design a Threaded Comment System like YouTube'sSystem design · reported at 1● JioHotstarSQ-19 · YouTube Video Platform →W04 · DAY 04 · Feed Caching →
- Design a train booking system like IRCTCSystem design · reported at 1● OlaSQ-11 · IRCTC Tatkal Ticket Booking System →LLD-05 · Design a Movie Ticket Booking System →
- Design a train ticket booking systemSystem design · reported at 1● SwiggySQ-11 · IRCTC Tatkal Ticket Booking System →LLD-05 · Design a Movie Ticket Booking System →
- Design a Train Ticket Booking System like IRCTCSystem design · reported at 1● MakeMyTripSQ-11 · IRCTC Tatkal Ticket Booking System →SQ-16 · BookMyShow Seat Booking →
- Design a travel booking service like Cleartrip with premium membershipSystem design · reported at 1● PaytmIP-19 · Design a Hotel Reservation System →W04 · DAY 05 · Multi-Tier Caching →
- Design a Unified User Profile Fed by Many Teams (LLD)Low-level design · reported at 1● JioHotstarW08 · DAY 03 · Data Modeling for Analytics →W08 · DAY 02 · Streaming vs Batch Processing →
- Design a UPI-like payment app (LLD)Low-level design · reported at 1● PaytmSQ-01 · India's UPI →IP-20 · Design a Payment System →
- Design a URL RouterLow-level design · reported at 1● Atlassian
- Design a Voting and Ranking SystemLow-level design · reported at 1● AtlassianIP-14 · Design a Real-Time Leaderboard →
- Design a warehouse management system for InstamartSystem design · reported at 1● SwiggySQ-12 · Blinkit Quick Commerce →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →W03 · DAY 02 · Transactional Outbox →
- Design a Weather App that Aggregates Third-Party ProvidersSystem design · reported at 1● PostmanW04 · DAY 01 · Caching Patterns →W02 · DAY 03 · Circuit Breakers →IP-06 · Design a Notification System →
- Design a Workflow OrchestratorLow-level design · reported at 1● Walmart Global TechW05 · DAY 03 · Saga Orchestration Deep Dive →IP-17 · Design a Distributed Job Scheduler →
- Design a Workflow Service for Cloud Resource ProvisioningSystem design · reported at 1● OracleW05 · DAY 03 · Saga Orchestration Deep Dive →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →
- Design an Ad Frequency Capping SystemSystem design · reported at 1● NetflixW01 · DAY 03 · Rate Limiting at Scale →W08 · DAY 01 · Event Ingestion at Scale →IP-16 · Design an Ad Click Aggregation System →
- Design an Ad Moderation PipelineSystem design · reported at 1● MetaW03 · DAY 04 · Dead Letters and Poison Pills →W03 · DAY 01 · Queue vs Stream →W08 · DAY 02 · Streaming vs Batch Processing →
- Design an ad pacing service for restaurant campaignsSystem design · reported at 1● ZomatoIP-16 · Design an Ad Click Aggregation System →W01 · DAY 03 · Rate Limiting at Scale →
- Design an ad serviceSystem design · reported at 1● MeeshoIP-16 · Design an Ad Click Aggregation System →
- Design an Ad-Playback Analytics PipelineSystem design · reported at 1● JioHotstarW08 · DAY 01 · Event Ingestion at Scale →IP-16 · Design an Ad Click Aggregation System →W08 · BOSS · Real-Time Analytics for Video Streaming Platform →
- Design an Airline Ticket Management SystemLow-level design · reported at 1● FlipkartLLD-05 · Design a Movie Ticket Booking System →SQ-11 · IRCTC Tatkal Ticket Booking System →
- Design an Alerting System (LLD)Low-level design · reported at 1● MakeMyTripIP-15 · Design a Metrics Monitoring and Alerting System →LLD-08 · Design a Logging Framework (Pub-Sub) →
- Design an API that counts orders in the last X minutesSystem design · reported at 1● ZomatoIP-16 · Design an Ad Click Aggregation System →W08 · DAY 02 · Streaming vs Batch Processing →
- Design an app version management systemLow-level design · reported at 1● PhonePeW10 · DAY 03 · Deployment Strategies →
- Design an ATM (LLD)Low-level design · reported at 1● Urban Company
- Design an e-commerce applicationSystem design · reported at 1● GrowwW04 · BOSS · Design a Global E-Commerce Product Catalog System →W03 · BOSS · Event-Driven Food Delivery Order System →
- Design an E-commerce Store (LLD)Low-level design · reported at 1● PayPalW04 · BOSS · Design a Global E-Commerce Product Catalog System →
- Design an E-commerce WebsiteSystem design · reported at 1● IntuitW04 · BOSS · Design a Global E-Commerce Product Catalog System →W03 · BOSS · Event-Driven Food Delivery Order System →
- Design an Employee On-Call Roster System like PagerDuty (LLD)Low-level design · reported at 1● Freshworks
- Design an ETA calculator by vehicle typeLow-level design · reported at 1● Paytm
- Design an In-Memory Cache with TTLLow-level design · reported at 1● NetflixLLD-02 · Design an LRU Cache →W04 · DAY 02 · Invalidation Strategies →
- Design an in-memory databaseLow-level design · reported at 1● CREDIP-03 · Design a Distributed Key-Value Store →
- Design an In-Memory Event Store for Real-Time QueriesLow-level design · reported at 1● AppleLLD-08 · Design a Logging Framework (Pub-Sub) →W08 · DAY 03 · Data Modeling for Analytics →
- Design an In-Memory Key-Value Store with Transactions (LLD)Low-level design · reported at 1● ZohoIP-03 · Design a Distributed Key-Value Store →W05 · DAY 01 · Consistency Models →
- Design an in-memory search engine for blog contentLow-level design · reported at 1● RazorpayW07 · DAY 02 · Indexing Pipeline →W07 · DAY 01 · Search Fundamentals & Architecture →
- Design an in-memory wallet and ledgerLow-level design · reported at 1● GrowwIP-20 · Design a Payment System →W03 · DAY 05 · Audit Log System →
- Design an internal app to track driversSystem design · reported at 1● OlaIP-13 · Design a Proximity Service →SQ-09 · Uber →
- Design an interview slot allocation systemLow-level design · reported at 1● FlipkartLLD-05 · Design a Movie Ticket Booking System →
- Design an intraday auto square-off risk serviceSystem design · reported at 1● GrowwSQ-13 · Zerodha Kite Trading Platform →W08 · DAY 01 · Event Ingestion at Scale →W02 · DAY 02 · Idempotency in Practice →
- Design an inventory management system for InstamartLow-level design · reported at 1● SwiggySQ-12 · Blinkit Quick Commerce →W02 · BOSS · The Ultimate System Design Interview →
- Design an Invoice and Commission SystemSystem design · reported at 1● IntuitIP-20 · Design a Payment System →W08 · DAY 03 · Data Modeling for Analytics →
- Design an Offline-Capable Payment SystemSystem design · reported at 1● AppleIP-20 · Design a Payment System →W05 · DAY 04 · Conflict Resolution →W09 · DAY 05 · Security Architecture →
- Design an Online Auction SystemSystem design · reported at 1● IntuitW01 · DAY 04 · Hot Keys and Skew →W05 · DAY 01 · Consistency Models →IP-14 · Design a Real-Time Leaderboard →
- Design an Online Judge (LeetCode)System design · reported at 1● MetaW03 · DAY 01 · Queue vs Stream →W09 · DAY 02 · Noisy Neighbor Prevention →IP-14 · Design a Real-Time Leaderboard →
- Design an orchestration serviceLow-level design · reported at 1● ShareChatW05 · DAY 03 · Saga Orchestration Deep Dive →
- Design an order and inventory management serviceLow-level design · reported at 1● MeeshoSQ-12 · Blinkit Quick Commerce →W02 · BOSS · The Ultimate System Design Interview →
- Design API monetisation with subscription plansSystem design · reported at 1● GrowwW01 · DAY 03 · Rate Limiting at Scale →W09 · DAY 02 · Noisy Neighbor Prevention →
- Design book searchSystem design · reported at 1● SwiggyW07 · DAY 01 · Search Fundamentals & Architecture →IP-09 · Design Typeahead Search (Autocomplete) →
- Design Browser History (LLD)Low-level design · reported at 1● Zoho
- Design Comments, Likes and FollowsSystem design · reported at 1● SalesforceIP-07 · Design a News Feed →W01 · DAY 04 · Hot Keys and Skew →
- Design Curbside PickupSystem design · reported at 1● Walmart Global TechIP-06 · Design a Notification System →IP-13 · Design a Proximity Service →
- Design DNSSystem design · reported at 1● AppleW00 · PART 4 · Networking Fundamentals for System Design →W04 · DAY 05 · Multi-Tier Caching →
- Design group chat with admin rulesLow-level design · reported at 1● GrowwIP-08 · Design a Chat System →
- Design lineup notifications sent before a match startsSystem design · reported at 1● Dream11IP-06 · Design a Notification System →W06 · DAY 04 · Scale, Reliability & Edge Cases →W01 · DAY 04 · Hot Keys and Skew →
- Design Live CommentsSystem design · reported at 1● MetaIP-08 · Design a Chat System →W04 · DAY 04 · Feed Caching →W03 · DAY 03 · Backpressure and Flow Control →
- Design Microservices for an E-commerce SystemSystem design · reported at 1● Morgan StanleyW03 · BOSS · Event-Driven Food Delivery Order System →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →W04 · BOSS · Design a Global E-Commerce Product Catalog System →
- Design order management and payments for a shipping platform like ShiprocketSystem design · reported at 1● PaytmW03 · BOSS · Event-Driven Food Delivery Order System →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →IP-20 · Design a Payment System →
- Design PastebinSystem design · reported at 1● AmazonIP-12 · Design Pastebin →SQ-08 · AWS S3 →
- Design People You May KnowSystem design · reported at 1● LinkedInW08 · DAY 02 · Streaming vs Batch Processing →W01 · DAY 01 · Partitioning Deep-Dive →
- Design Restaurant Search for a Food Delivery AppLow-level design · reported at 1● SalesforceW07 · DAY 03 · Query Processing & Relevance →SQ-17 · Swiggy Food Delivery →
- Design ride poolingSystem design · reported at 1● OlaSQ-09 · Uber →IP-13 · Design a Proximity Service →
- Design SIP creation and scheduled transactionsLow-level design · reported at 1● GrowwIP-17 · Design a Distributed Job Scheduler →W02 · DAY 02 · Idempotency in Practice →
- Design Stack OverflowLow-level design · reported at 1● SalesforceW07 · DAY 01 · Search Fundamentals & Architecture →W07 · DAY 02 · Indexing Pipeline →
- Design the Database for a Social Media App (LLD)Low-level design · reported at 1● NykaaIP-07 · Design a News Feed →W08 · DAY 03 · Data Modeling for Analytics →
- Design the Database Schema for a Chat SystemLow-level design · reported at 1● MakeMyTripIP-08 · Design a Chat System →SQ-02 · WhatsApp Messaging →
- Design the Database Schema for TwitterSystem design · reported at 1● BrowserStackSQ-10 · Twitter/X →W01 · DAY 01 · Partitioning Deep-Dive →
- Design the microservices for a fashion e-commerce appSystem design · reported at 1● MyntraW04 · BOSS · Design a Global E-Commerce Product Catalog System →W03 · BOSS · Event-Driven Food Delivery Order System →
- Design the schema for delivery partners and ordersSystem design · reported at 1● ZomatoSQ-17 · Swiggy Food Delivery →W06 · BOSS · Food Delivery Order System →
- Design Top-K Frequent Items in a StreamConcept · reported at 1● AdobeIP-16 · Design an Ad Click Aggregation System →W08 · DAY 02 · Streaming vs Batch Processing →
- Design Top-K Trending ArticlesSystem design · reported at 1● LinkedInIP-16 · Design an Ad Click Aggregation System →W08 · DAY 02 · Streaming vs Batch Processing →IP-14 · Design a Real-Time Leaderboard →
- Design Twitter (LLD)Low-level design · reported at 1● IntuitSQ-10 · Twitter/X →IP-07 · Design a News Feed →
- Design Undo for Deleted Collections with a TTLLow-level design · reported at 1● PostmanW09 · DAY 04 · Right to Deletion →
- Design Video View Counts and Watch HistorySystem design · reported at 1● JioHotstarIP-16 · Design an Ad Click Aggregation System →W01 · DAY 04 · Hot Keys and Skew →SQ-19 · YouTube Video Platform →
- Explain Kafka's architecture and componentsConcept · reported at 1● MyntraW03 · DAY 01 · Queue vs Stream →IP-18 · Design a Distributed Message Queue →
- Find the Top K Users Logging In Each Day at Millions of LoginsSystem design · reported at 1● JPMorgan ChaseIP-14 · Design a Real-Time Leaderboard →IP-16 · Design an Ad Click Aggregation System →W01 · DAY 04 · Hot Keys and Skew →
- How do circuit breakers make services resilient?Concept · reported at 1● MyntraW02 · DAY 03 · Circuit Breakers →W02 · DAY 01 · Timeout Hell →
- How do Kafka partitions affect ordering and consumer idempotency?Concept · reported at 1● ZomatoW03 · DAY 01 · Queue vs Stream →W02 · DAY 02 · Idempotency in Practice →
- How do you deprecate a feature while rolling out its replacement to clients?Concept · reported at 1● InMobiW10 · DAY 03 · Deployment Strategies →
- How do you find a performance issue in production?Concept · reported at 1● Morgan StanleyW10 · DAY 02 · Observability →W10 · DAY 05 · Incident Management →
- How do you remove duplicate lines from a 10 GB file with 2 GB of memory?Concept · reported at 1● Morgan StanleyW08 · DAY 02 · Streaming vs Batch Processing →W01 · DAY 01 · Partitioning Deep-Dive →
- How do you send a push notification to one specific device?Concept · reported at 1● RapidoW06 · DAY 02 · Core Notification Flow →IP-06 · Design a Notification System →
- How do you serve 500k records to a browser efficiently?Concept · reported at 1● JPMorgan ChaseW04 · DAY 01 · Caching Patterns →W07 · DAY 05 · Search Operations & Scale →
- How does a hash table work internally, and how do you make it thread-safe?Concept · reported at 1● InMobiW00 · PART 5 · Operating System Concepts for System Design →
- How does a load balancer work?Concept · reported at 1● SprinklrW00 · PART 2 · Infrastructure Building Blocks →W00 · PART 4 · Networking Fundamentals for System Design →
- How does change data capture work?Concept · reported at 1● Dream11W03 · DAY 02 · Transactional Outbox →
- How does consistent hashing work?Concept · reported at 1● FreshworksW01 · DAY 01 · Partitioning Deep-Dive →IP-03 · Design a Distributed Key-Value Store →
- How does OS process scheduling work?Concept · reported at 1● JuspayW00 · PART 5 · Operating System Concepts for System Design →
- How would you count the words in a very large file efficiently?Concept · reported at 1● BrowserStackW08 · DAY 02 · Streaming vs Batch Processing →W00 · PART 5 · Operating System Concepts for System Design →
- How would you find every text file that contains a given word?Concept · reported at 1● SprinklrW07 · DAY 01 · Search Fundamentals & Architecture →W07 · DAY 02 · Indexing Pipeline →
- How would you host a website without any external service?Concept · reported at 1● BrowserStackW00 · PART 4 · Networking Fundamentals for System Design →W00 · PART 2 · Infrastructure Building Blocks →
- How would you prepare your system for the IPL?Concept · reported at 1● Dream11W10 · DAY 04 · Capacity Planning →W10 · DAY 03 · Deployment Strategies →
- How would you send a large sorted stream of numbers efficiently from an API?Concept · reported at 1● Morgan StanleyW00 · PART 4 · Networking Fundamentals for System Design →W03 · DAY 03 · Backpressure and Flow Control →
- Implement a lock without mutexes, semaphores or atomicsConcept · reported at 1● JuspayW00 · PART 5 · Operating System Concepts for System Design →
- Implement a Producer-Consumer QueueLow-level design · reported at 1● Morgan StanleyW03 · DAY 03 · Backpressure and Flow Control →W00 · PART 5 · Operating System Concepts for System Design →
- Implement a Queueing Service as a LibraryLow-level design · reported at 1● JioHotstarIP-18 · Design a Distributed Message Queue →LLD-08 · Design a Logging Framework (Pub-Sub) →
- Implement an In-Memory Cache like Redis in Java (LLD)Low-level design · reported at 1● ZohoLLD-02 · Design an LRU Cache →IP-11 · Design a Distributed Cache →
- Isolation levels and pessimistic vs optimistic lockingConcept · reported at 1● Dream11W05 · DAY 01 · Consistency Models →
- MongoDB or Postgres, and what is the finest grain of concurrency control in a database?Concept · reported at 1● Morgan StanleyW05 · DAY 01 · Consistency Models →W00 · PART 2 · Infrastructure Building Blocks →
- Monolith or microservices, and should each microservice own its database?Concept · reported at 1● RapidoW00 · PART 1 · System Design Fundamentals →W03 · DAY 02 · Transactional Outbox →
- Networking fundamentals deep diveConcept · reported at 1● JuspayW00 · PART 4 · Networking Fundamentals for System Design →
- Parse JSON from a URL and answer count queriesLow-level design · reported at 1● Ola
- Pessimistic vs optimistic locking and transaction isolation levelsConcept · reported at 1● PaytmW05 · DAY 01 · Consistency Models →
- Scale a Monolith to 50x Traffic and Integrate a Prediction ServiceSystem design · reported at 1● JPMorgan ChaseW10 · DAY 04 · Capacity Planning →W04 · DAY 01 · Caching Patterns →W02 · DAY 03 · Circuit Breakers →
- Sharding, SQL vs NoSQL, and ACID vs CAPConcept · reported at 1● PaytmW01 · DAY 01 · Partitioning Deep-Dive →W00 · PART 6 · System Design Terminology & Theory →
- Sort petabytes of data spread across 10,000 disksSystem design · reported at 1● ShareChatW08 · DAY 02 · Streaming vs Batch Processing →W01 · DAY 01 · Partitioning Deep-Dive →
- SQL or NoSQL, and when does an index not help?Concept · reported at 1● RapidoW00 · PART 2 · Infrastructure Building Blocks →W00 · PART 6 · System Design Terminology & Theory →
- What changes when you take a production app beyond one country?Concept · reported at 1● AtlassianW09 · DAY 03 · Data Residency and GDPR →W01 · DAY 02 · Replication Trade-offs →
- What goes wrong in a master-slave setup, and how do you debug it?Concept · reported at 1● InMobiW01 · DAY 02 · Replication Trade-offs →W05 · DAY 05 · Leader Election and Coordination →
- What happens when Kafka consumers lag behind producers?Concept · reported at 1● ZomatoW03 · DAY 03 · Backpressure and Flow Control →W03 · DAY 01 · Queue vs Stream →
- What is horizontal versus vertical scaling?Concept · reported at 1● RapidoW00 · PART 1 · System Design Fundamentals →W10 · DAY 04 · Capacity Planning →
- What problems does consistent hashing leave unsolved?Concept · reported at 1● AtlassianW01 · DAY 01 · Partitioning Deep-Dive →W01 · DAY 04 · Hot Keys and Skew →
- When would you use Kafka versus SNS, and how do you design retries?Concept · reported at 1● NykaaW03 · DAY 01 · Queue vs Stream →W03 · DAY 04 · Dead Letters and Poison Pills →W02 · DAY 01 · Timeout Hell →
- Which database would you choose for large volumes of unstructured data?Concept · reported at 1● JPMorgan ChaseW00 · PART 2 · Infrastructure Building Blocks →W00 · PART 6 · System Design Terminology & Theory →
- Why is Redis fast while being single-threaded?Concept · reported at 1● ZomatoIP-11 · Design a Distributed Cache →W04 · DAY 01 · Caching Patterns →
- Write a Client Library Wrapping the BrowserStack REST APILow-level design · reported at 1● BrowserStackW02 · DAY 01 · Timeout Hell →W02 · DAY 02 · Idempotency in Practice →
- Design an E-commerce Flash SaleSystem design○ Amazon○ CRED○ Flipkart○ Myntra○ Nykaa○ Walmart Global TechW02 · BOSS · The Ultimate System Design Interview →W01 · DAY 04 · Hot Keys and Skew →W04 · DAY 03 · Thundering Herd →
- Design a Multi-Tenant SaaS PlatformSystem design○ Adobe○ Atlassian○ Intuit○ SalesforceW09 · BOSS · Design a Multi-Tenant Enterprise SaaS Platform →W09 · DAY 02 · Noisy Neighbor Prevention →W09 · DAY 01 · Tenant Isolation Strategies →
- Design an Ad Click Aggregation SystemSystem design○ InMobi○ Meta○ ShareChatIP-16 · Design an Ad Click Aggregation System →W08 · DAY 04 · Late-Arriving Data and Correctness →
- Design an e-commerce product catalogue and searchSystem design○ Flipkart○ Meesho○ MyntraW04 · BOSS · Design a Global E-Commerce Product Catalog System →W07 · DAY 01 · Search Fundamentals & Architecture →W07 · DAY 03 · Query Processing & Relevance →
- Design live market-data streaming to millions of clientsSystem design○ Groww○ ZerodhaSQ-13 · Zerodha Kite Trading Platform →W03 · DAY 03 · Backpressure and Flow Control →W08 · DAY 01 · Event Ingestion at Scale →
- Design webhook delivery with retriesSystem design○ Juspay○ RazorpayW02 · DAY 04 · Webhook Delivery System →W03 · DAY 04 · Dead Letters and Poison Pills →
- Design a Captain Wallet and Daily PayoutsSystem design○ RapidoIP-20 · Design a Payment System →W02 · DAY 02 · Idempotency in Practice →W03 · DAY 05 · Audit Log System →
- Design a Card Payment NetworkSystem design○ StripeSQ-04 · Visa/Mastercard Global Payment Network →IP-20 · Design a Payment System →
- Design a card tokenisation vaultSystem design○ JuspayW09 · DAY 05 · Security Architecture →SQ-04 · Visa/Mastercard Global Payment Network →
- Design a Cloud Device Farm that Allocates Real Browsers and Phones to Test SessionsSystem design○ BrowserStackW09 · DAY 02 · Noisy Neighbor Prevention →IP-17 · Design a Distributed Job Scheduler →W01 · DAY 05 · Session Store Design →
- Design a Double-Entry LedgerSystem design○ StripeIP-20 · Design a Payment System →W03 · DAY 05 · Audit Log System →W03 · DAY 02 · Transactional Outbox →
- Design a Hotel Reservation SystemSystem design○ MakeMyTripIP-19 · Design a Hotel Reservation System →W05 · DAY 02 · Distributed Transactions — The Saga Pattern →
- Design a Multi-Tenant CRM PlatformSystem design○ ZohoW09 · BOSS · Design a Multi-Tenant Enterprise SaaS Platform →W09 · DAY 01 · Tenant Isolation Strategies →W09 · DAY 03 · Data Residency and GDPR →
- Design a Multi-Tenant Helpdesk Ticketing SystemSystem design○ FreshworksW09 · BOSS · Design a Multi-Tenant Enterprise SaaS Platform →W09 · DAY 01 · Tenant Isolation Strategies →W09 · DAY 02 · Noisy Neighbor Prevention →
- Design a payment router across multiple gatewaysSystem design○ JuspaySQ-18 · Razorpay Payment Gateway →W02 · DAY 03 · Circuit Breakers →W02 · DAY 01 · Timeout Hell →
- Design a Personalised Lock-Screen Content FeedSystem design○ InMobiIP-07 · Design a News Feed →W04 · DAY 04 · Feed Caching →SQ-21 · Instagram Feed and Stories →
- Design a Product CatalogSystem design○ Walmart Global TechW04 · BOSS · Design a Global E-Commerce Product Catalog System →W04 · DAY 02 · Invalidation Strategies →
- Design a Product Catalog with Search and FiltersSystem design○ NykaaW04 · BOSS · Design a Global E-Commerce Product Catalog System →W07 · DAY 01 · Search Fundamentals & Architecture →W07 · DAY 04 · Advanced Search Features →
- Design a Real-Time Bidding Ad ServerSystem design○ InMobiW02 · DAY 01 · Timeout Hell →W04 · DAY 05 · Multi-Tier Caching →W01 · DAY 04 · Hot Keys and Skew →
- Design a Real-Time Market Data Distribution SystemSystem design○ Morgan StanleyW03 · DAY 01 · Queue vs Stream →W03 · DAY 03 · Backpressure and Flow Control →SQ-13 · Zerodha Kite Trading Platform →
- Design a rewards points ledgerSystem design○ CREDW03 · DAY 05 · Audit Log System →W03 · DAY 02 · Transactional Outbox →
- Design a Scheduled API Monitoring ServiceSystem design○ PostmanIP-17 · Design a Distributed Job Scheduler →IP-15 · Design a Metrics Monitoring and Alerting System →W09 · DAY 02 · Noisy Neighbor Prevention →
- Design a Search EngineSystem design○ GoogleSQ-05 · Google Search →W07 · DAY 03 · Query Processing & Relevance →IP-05 · Design a Web Crawler →
- Design a session store with two-factor loginSystem design○ ZerodhaW01 · DAY 05 · Session Store Design →W09 · DAY 05 · Security Architecture →
- Design a short-video feed like MojSystem design○ ShareChatSQ-21 · Instagram Feed and Stories →SQ-19 · YouTube Video Platform →
- Design a Social Listening Pipeline that Ingests Posts from Many NetworksSystem design○ SprinklrW08 · DAY 01 · Event Ingestion at Scale →W03 · DAY 03 · Backpressure and Flow Control →W07 · DAY 02 · Indexing Pipeline →
- Design a Surge Pricing EngineSystem design○ RapidoW08 · DAY 02 · Streaming vs Batch Processing →SQ-09 · Uber →
- Design a Tamper-Evident Transaction Audit LogSystem design○ JPMorgan ChaseW03 · DAY 05 · Audit Log System →W09 · DAY 05 · Security Architecture →
- Design a Test Logs and Results PipelineSystem design○ BrowserStackW08 · DAY 01 · Event Ingestion at Scale →W10 · DAY 02 · Observability →SQ-08 · AWS S3 →
- Design a Unified Customer-Care Inbox with Agent RoutingSystem design○ SprinklrW09 · BOSS · Design a Multi-Tenant Enterprise SaaS Platform →IP-08 · Design a Chat System →W03 · DAY 01 · Queue vs Stream →
- Design a Video Viewing Analytics PipelineSystem design○ NetflixW08 · BOSS · Real-Time Analytics for Video Streaming Platform →W08 · DAY 02 · Streaming vs Batch Processing →W08 · DAY 04 · Late-Arriving Data and Correctness →
- Design a Web Analytics PipelineSystem design○ AdobeW08 · DAY 01 · Event Ingestion at Scale →W08 · DAY 03 · Data Modeling for Analytics →W08 · DAY 05 · Query Layer and Optimization →
- Design Ad Frequency Capping and Budget PacingSystem design○ InMobiW01 · DAY 03 · Rate Limiting at Scale →IP-16 · Design an Ad Click Aggregation System →
- Design an API GatewaySystem design○ ZerodhaW09 · DAY 05 · Security Architecture →W09 · DAY 02 · Noisy Neighbor Prevention →
- Design an Audit Log SystemSystem design○ Goldman SachsW03 · DAY 05 · Audit Log System →W09 · DAY 05 · Security Architecture →
- Design an Email Service like Zoho MailSystem design○ ZohoW06 · DAY 01 · Notification Platform — Problem Understanding & High-Level Design →W07 · DAY 02 · Indexing Pipeline →IP-10 · Design a File Sync Service (Dropbox / Google Drive) →
- Design an Object Storage ServiceSystem design○ OracleSQ-08 · AWS S3 →IP-03 · Design a Distributed Key-Value Store →W01 · DAY 02 · Replication Trade-offs →
- Design contest joining before the match deadlineSystem design○ Dream11W02 · BOSS · The Ultimate System Design Interview →W01 · DAY 04 · Hot Keys and Skew →W03 · DAY 03 · Backpressure and Flow Control →
- Design credit card bill payments with remindersSystem design○ CREDIP-20 · Design a Payment System →W02 · DAY 02 · Idempotency in Practice →IP-06 · Design a Notification System →
- Design end-of-day reconciliation and contract-note generationSystem design○ ZerodhaW08 · DAY 02 · Streaming vs Batch Processing →W02 · DAY 05 · Distributed Cron & Job Scheduling →W03 · DAY 05 · Audit Log System →
- Design Flight Search with Cached Fares from Many SuppliersSystem design○ MakeMyTripW04 · DAY 02 · Invalidation Strategies →W04 · DAY 05 · Multi-Tier Caching →W02 · DAY 01 · Timeout Hell →
- Design idempotent payment APIsConcept○ JuspayW02 · DAY 02 · Idempotency in Practice →
- Design Inventory Reservation across Warehouses and StoresSystem design○ NykaaW05 · DAY 02 · Distributed Transactions — The Saga Pattern →W03 · DAY 02 · Transactional Outbox →SQ-12 · Blinkit Quick Commerce →
- Design Live Captain Location Tracking and ETASystem design○ RapidoSQ-09 · Uber →W08 · DAY 01 · Event Ingestion at Scale →W03 · DAY 03 · Backpressure and Flow Control →
- Design live score and points updates for millions of usersSystem design○ Dream11W04 · DAY 04 · Feed Caching →W08 · DAY 02 · Streaming vs Batch Processing →
- Design Live Streaming of a Cricket Match to Tens of Millions of ViewersSystem design○ JioHotstarSQ-06 · Netflix Streaming →W04 · DAY 03 · Thundering Herd →W10 · DAY 04 · Capacity Planning →
- Design Live Streaming of a Remote Browser Session to the UserSystem design○ BrowserStackW03 · DAY 03 · Backpressure and Flow Control →W00 · PART 4 · Networking Fundamentals for System Design →
- Design Matching of Home-Service Professionals to BookingsSystem design○ Urban CompanyIP-13 · Design a Proximity Service →SQ-09 · Uber →W05 · DAY 01 · Consistency Models →
- Design order placement that survives the market-open spikeSystem design○ ZerodhaSQ-13 · Zerodha Kite Trading Platform →W01 · DAY 04 · Hot Keys and Skew →W02 · DAY 01 · Timeout Hell →
- Design portfolio and P&L reports over years of tradesSystem design○ ZerodhaW08 · DAY 03 · Data Modeling for Analytics →W08 · DAY 05 · Query Layer and Optimization →W01 · DAY 01 · Partitioning Deep-Dive →
- Design price alerts and good-till-triggered ordersSystem design○ ZerodhaIP-17 · Design a Distributed Job Scheduler →IP-06 · Design a Notification System →
- Design Real-Time Card Fraud DetectionSystem design○ JPMorgan ChaseW08 · DAY 02 · Streaming vs Batch Processing →SQ-04 · Visa/Mastercard Global Payment Network →W02 · DAY 01 · Timeout Hell →
- Design recurring mutual fund SIP ordersSystem design○ ZerodhaIP-17 · Design a Distributed Job Scheduler →W02 · DAY 02 · Idempotency in Practice →
- Design Scheduled Publishing to Social NetworksSystem design○ SprinklrIP-17 · Design a Distributed Job Scheduler →W01 · DAY 03 · Rate Limiting at Scale →W02 · DAY 04 · Webhook Delivery System →
- Design Slot Availability and Booking for Service ProfessionalsSystem design○ Urban CompanyIP-19 · Design a Hotel Reservation System →SQ-16 · BookMyShow Seat Booking →W02 · DAY 02 · Idempotency in Practice →
- Design surge pricingSystem design○ OlaSQ-09 · Uber →W08 · DAY 02 · Streaming vs Batch Processing →
- Design telemetry ingestion for connected electric scootersSystem design○ OlaW08 · DAY 01 · Event Ingestion at Scale →IP-15 · Design a Metrics Monitoring and Alerting System →W08 · DAY 04 · Late-Arriving Data and Correctness →
- Design Workspace Sync for Shared API CollectionsSystem design○ PostmanIP-10 · Design a File Sync Service (Dropbox / Google Drive) →W05 · DAY 04 · Conflict Resolution →
- How do circuit breakers and fallbacks keep a microservice platform up?Concept○ NetflixW02 · DAY 03 · Circuit Breakers →W02 · DAY 01 · Timeout Hell →
- How do idempotency keys make payment API retries safe?Concept○ StripeW02 · DAY 02 · Idempotency in Practice →W02 · DAY 01 · Timeout Hell →
- How would you roll out a change safely across regions?Concept○ NetflixW10 · DAY 03 · Deployment Strategies →W10 · DAY 05 · Incident Management →