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Please look through the list to make sure your question isn't already there.Design Instagram
Design a photo-sharing service like Instagram, where users can upload photos to share them with other users.
Payment System
A payment system similar to Stripe or PayPal.
Design a Flash Sale Site
Limited number of items for sale with millions of active buyers fighting for remaining items
Design distributed rate limiter
- Design a horizontally scalable distributed rate limiting solution to prevent facebook's public api abuse
Design "likes" counter
Design a system that tracks the number of “likes” (posts / tweets / photos) at scale.
Design Facebook post privacy functionality
Users have the ability to choose the privacy of their posts (Only me, Friends, Public). If possible, also get into Friends of friends and custom lists.
Design the auto-complete/type-ahead backend
Design the backend for an auto-complete system, like Meta, Google or Amazon.
Design a recommendation system for netflix/prime/Hulu to recommend movie
Design a recommendation system for netflix/prime/Hulu to recommend movies or TV shows
Design CamelCamelCamel
price tracking system
Design Metrics Monitoring and Alerting System
Design meta chess
- Design meta chess. Store all the games and events and player moves. How do you design "undo" if each player can undo their last (or their two last) move(s)? Compute and maintain the scoreboard of billions of players? Top 100 games and winners.
Design Google Calendar
Design a calendar service that people can create events, invite others and suggest meeting rooms
Deep Dive - DynamoDB
Deep Dive - PostgreSQL
Create Key/Value Store
Design distributed message queue
Functional Requirements - Client should be able to create a queue - Producer should be able to send message - Consumers should be able to receive messages - Consumer should be able to delete a message - delete queue.
Design a leaderboard
User's have a list of friends and can see their leaderboard ranking among their friends and among global users. System should scale to millions of users per day.
Deep Dive - Kafka
Deep Dive - Cassandra
Design payment system
Lime Venmo, PayPal
Distributed Logging and analysis
Petabytes of data per second ingestion, petabytes of data per second while querying.
Design a blob store like s3
Recoomendation system in Netflix
Design Spotify
Design a notification service
Notification to other services or notification to users
Design ChatGPT
Deep Drives Apach Flink
Five deep drives of Apach FLink and how to use it, why to use it and compare it with the other tool
Design Google Maps
Design CDN
we have to build content delivery network
Design an E-Commerce System
Design an E-Commerce system with a functionality to handle billion $ sale days.
Deep Dive Elastic Search
Design Booking.com
Hotel booking app like Booking.com, Agoda etc
Design ZooKeeper
Design a Parking Lot
Design GoogleMeet
Online realtime video conferencing tool
Design a Rate Limiter
Design digital wallet
Users can check the wallet balance, add/view transactions and support transfer between accounts.
Design meta chess
- Design meta chess. Store all the games and events and player moves. How do you design "undo" if each player can undo their last (or their two last) move(s)? Compute and maintain the scoreboard of billions of players? Top 100 games and winners.
Design YouTube
Design amazon product/inventory management
Design Status Search
Context: Every user can post something as "status", at any given time, one user can only have one status (vs multiple posts). Build a search system which should enable users to search the statuses.
Design web crawler
Meta twists this question a bit and asks peer to peer approach assuming we have 10,000 phones or machines and use those to crawl the web. No system design course has clearly demonstrated this so far, so I am really interested to see your take Evan.
Design a Single Server Memcached
Might also extend that to cluster level memcached as well.
Transactions deep dive
Can you please explain how transactions work internally. For example how rollback will work in a simple in-memory key value store. Also it will be great if you can touch upon the distributed transactions. Thanks.
Design Live Video Streaming System
Designing a Live Video Streaming System Like ESPN
Tagging System
multiple services would like to store tags Cofluence for page, Jira for tickets and etc with CRUD and things like all pages per tag, dashboards and etc.
Deep Dive - ETCD/Zookeeper
Design Twitter
Design weather app
Design Stock Exchange
A lot of system design for stock exchanges out there focus on distributed systems rather than the requirement of low latency order matching which should be done in memory rather than utilizing queues and what not. Would love your perspective
Design Google News
Any news aggregator service
Design Zoom
wonder how this differs from designing whats app
Deep DIves: Apache Flink
Design a billing system
Design Shopify
Design Shopify, an e-commerce platform where users can easily create and manage isolated web stores with customizable templates, APIs, plugins, and automated hosting. Ensure scalability, security, and efficient monitoring and maintenance.
Design Live Streaming System
Like Hotstar, Youtube or Netflix where millions of users are watching concurrently. How to minimize the live feed latency and scale for sudden spike and drop in traffic. System should be able to handle 50M-100M concurrent users at a time.
Deep Dive MapReduce
MapReduce, Hadoop, HBase, Hive..
Design a food delivery app
A food delivery app like doordash or swiggy or zomato
Design I18N and L10N system
- Build system that helps developers to add new strings in application - Also allow auditing of those string - string should handle pronouns, numbers, format, unit conversion etc.... - manual verification vs ML verification - enable translators
Google photos
Design Slack
Design url shorter system.
Design distributed url shorter systems like tinyurl, linkedin etc.
Job scheduler
- scheduling job - dag scheduling
Design a banking app
Deep Dive: TimeSeries Database
Design Cab Sharing / Ride Sharing App
Multiple (3-4) user can share a cab, it can be either like Uber cab sharing or something like if I am driving from point a to b as a user I post that & anyone willing to travel on same route can pair with me and pay me for the part of ride, quickride
Mock interview to get requirements
This is not an interview question specifically, but with both Evan and Stefan, I think it could be helpful to watch how an interviewee susses out requirements in a mock scenario without having practiced or knowing the problem.
Deep Dive - Spark
Design FIFO Pubsub system
Design a Pubsub system that makes guarantee FIFO delivery. I was asked this question during my interview.
Distribute 6M burgers in 10 minutes.
No one should get more than 1 burger. We should distribute exactly 6M burgers.
Design Proximity Service like Yelp
Deep Dives - Kafka
Deep dive - Zookeeper
Deep Dives - Kubernetes
How to design a Ledger System for Payment Gateway
Asked in Stripe
Design Twitter/ X Trending hashtags
Find top k hastags based on location and category. User can also search for past trending hastags
Design Splunk - Logging and Metrics Monitoring System
Design a Feature Flag System
- Millions of users - Target individual users and % of users - Admin UI - Backend only
Design Machine Learning Platform
Design subscription system
Got asked at Google
Design Online Judge
A online coding judge like Leetcode which hosts coding contests, allows users to test and submit code, tallies scores and maintains a leaderboard
Design a hotel booking system
Design chess game between human and ai
- Determine how points are assigned for every move and how to determine winner/looser/draw state
Distributed high scale telemetry system
Telemetry/Metrics system such as Datadog, Splunk etc
Design google calendar
Focusing on the notification system (users can be in different time zones, each reminder should be sent only once, set reminders with frequency/interval, i.e. once a week, twice a month, etc.)
Design YouTube
Design Advertising Platform for Ad Reporting
1. Analytical Load Serving 2. Data Skewness handling 3. Realtime Reporting
Design WhatsApp
Design a Notification Delivery System.
Something like One signal.
Design Robinhood
- Live stock price updates per second of 7000 tickers - Getting historical data of a stock for a timeframe for displaying the chart. The stock exchange in this case gives all the data points for a stock. For 1 month, all the data points each second
Design a webhook
A webhook can be a POST http endpoint called by an authenticated third party client. The client will call the webhook with a url and a message payload. The webhook should lookup the URL in the internal database registry and send the message to it.
Design Amazon Lockers
1. User can select nearby lockers at checkout. 2. System should generate OTP until used by user to unlock locker.
Design Code Deployment
Global and fast code deployment system.The system take the code. Builds the code into a binary and deploys the code globally in an efficient way. scale and deploy code to application servers all around the world. Addition NF requirements
Deepdive MongoDB
Designing a key value store like Redis
design Chat GPT
Design a multiplayer game matchmaking system
User's should be able to join matches of 12 players. Matching should be as fast as possible while keeping players close together. Players should be matched on their skill level (Win:Loss ratio etc). Should support ~1M players concurrently.
Design Tiktok
short video platform such as Tiktok, youtube shorts, etc.
Design a bidding system
Where users can bid
Design Gmail/Outlook
send and receive an email including attachments, filter and search through emails, and add tags to label emails
Design Google Calendar
google calendar - unique link generation, emphasis on how to store a meeting invite with multiple participants - which is recurring, reads (across globe) and writes - create, update, delete are efficient
Design a typeahead feature
Deep Dive on API design: RestAPI and GraphQL
Design Amazon
E-Commerce checkout!
Blocking IPs from a specific country
We can't serve data to banned IP addresses. This country exposes a web interface - http://security.gov.x/ - that just tells us for any given IP address if it’s banned or not. you have to solve it within two months so no need hot fix but no redesign.
HTTP downloader
Design Peer to Peer Payment System
Like Venmo/Cash app allowing people to send money to other people.
Design a Distributed Job Scheduler for Millions of Tasks in Daily Operation
Recommendation Systems
Video recommendation, Product recommendation etc..
Design Github/Gitlab
Online Bank
Design online banking system
Design Steam
Game creators, can create new games, publish and upload files. Users can search for games, add to cart, buy and download.
Design a reminder service
Users can schedule a onetime or recurring reminder which will send an email / push notification to the user. The reminder should be delivered exactly once within 5 minutes of the time. It should scale to millions of users.
PSP like VISA
Design a payment service provider like VISA.
Design google calendar
Focusing on the notification system (users can set reminders with frequency/interval, i.e. once a week, twice a month, etc.)
Design credit card system
System to process millions of transactions, always validating the customer's limit in every transaction
Deep Dive - Raft v/s Paxos
Design Mint like platform
A personal financial management platform for comprehensive view of finances in secure way.
Flights Aggregator - Skyscanner
deep dive into flink
Design an authentication service
An IdP like Okta that can perform federation and access to cloud-based apps.
Deep Dive - ZooKeeper
Design a time series db
Design a money transfer application
Design a distributed counter
design jenkins
Design CI/CD system such as jenkins.
Deep dive on Elastic Search
Deep Dive - ElasticSearch
Explore Distributed Concurrency Control
Go deeper into concurrency control between multiple instances of a microservice. For example, in the Ticket Master exercise, explore how we could control the concurrency when multiple instances of the Booking microservice tries reservice same ticket
Design Paypal
Deep Dive Cockroach DB
Design an in-memory db
Design a rate limiter
Design whatsapp/messenger
Planet Scale Metrics Ingestion Platform
Backend infrastructure for a metrics platform that scales for several zones/regions across the globe for ingestion and support queries for alerts, and on-demand incident response
We could use a dark mode on this site
Design Distributed Logging/Tracing
A system like jaeger
Design Snapchat
Designing a Music Recognition System like Shazam
system should be able to identify a song by listening to a short audio clip provided by the user. Once identified, the system should return details about the song, including the title, artist, album, and a link to listen to the full track.
Design a Telemetry Sysytem
Like Prometheus. Connect with external apps, record metrics, failures, events and logging.
Design Batch Processing System
Deep Dive: GraphQL
Design ESPN Fantasy Sports
App that allows users to create and join fantasy sports leagues for a variety of sports. Design Gaming app to handle millions of concurrent users, providing real-time updates, league management, and live scoring
Design video sharing website (twitch) copyright video detection
Design a service similar to twitch that flags and deletes copyrighted audio in videos if another user has uploaded it (copyright infringement)
Design a payroll system
For HR type software
Design a price alert system
Design Version Control system
Design a system like github
Tagging service system design
https://leetcode.com/discuss/interview-question/system-design/838025/Design-a-tagging-system-like-tags-used-in-stack-overflow
Design a distributed lock with TTL
design YouTube
Youtube/ Netflix
Design a Fitness app
Tracks biometrics based on geolocation and activity
Secure System Design for existing problems
Would be great to have some examples on how to approach secure system design interviews. Most of these focus on the SWE perspective but would be helpful to refocus around security engineering interviews.
Create a digital wallet
short url system design
system design for generating short urls and routing the short urls
Design a proximity Service
Design Block Storage System .
I was asked this question within Amazon . The question is "Design a block storage system that can reduce the fragmentation of the disk and provide durable storage devices on demand" . Something like AWS Elastic Block Storage.
Design a distributed load balancer
Distributed load balancer optimising for different work loads
Design the Google Doc
Design IAM system
Design Weather App
Design a weather app that would retrieve data from NWS in hourly fashion When a user requests for weather data, he should get the most recent one. <10 stale data is acceptable
Design Tiktok
Design Instagram Live
Design Webhook
Design Reddit
Forum for discussion
Design Recommendation System
Something like Amazon's "Customers who bought this, also bought these N items"
Deign Google Photos
Design AuthN & AuthZ system
LLD Interview Guides
Please make some sort of LLD interview guide.. 1) Can be like the hurry section for system design 2) Or specific problems
gossip protocol deepdive
Design a heat map
Create a system where every driver is sending their location in real time, plot a heatmap showing the number of drivers in particular location in last 20 minutes, consider 1 minute bucket.
Design a donation app
Should be a limited event for donation. Participants should be able to donate to different companies. Show donation received so far. You can add constraints as needed.
Web Crawler
Design a webcrawler
Job Scheduling
Design a scalable job schedulable that can schedule jobs in a perodic mannner
Design a centralized notification system
A social media app sends multiple notification to users. Different notifications are owned by different teams. Create a system which will be used by various team to send notifications immediately or in future.
Design Coding Contest Platform
photo sharing app like Instagram
Design what database to choose
This is more kind of an overview. Can you guys make a video on what database needs to be chosen for different type of use cases.
Design Youtube
Design Youtube for upload, search and view features
Design Robinhood
Robinhood - how it gives real time stock data and handles market crashes
Sports Live Streaming
Streaming sports matches to millions of users in real time.
Gmail
Design Google sheets
Design Venmo/Paypal
Fintech being on the rise, design a system like venmo or paypal that makes it easy for users to send/receive money to/from each other. Staff/Senior: After you've implemented the system, discuss the security implementation you would consider.
Design Shopify
Design a chat app
Design a chat app that support instant messaging (1-1, group chat).
Design a file system
Design a file system that can store 100s of PB of data. It offers POSIX semantics.
Design a hotel reservation system
Hotel reservation system question has some nuances. It can be as simple as a single hotel reservation to all the way up to a hotel chain reservation. This is different from Booking.com, as that site doesn't handle the actual reservation itself.
Deep dive data warehouses
Deep Dives - Zookeeper
Design Robinhood/Stock trading platform
System that can be more as an orchestrator between client and stock exchange for real-time prices. Also, execute trade with the lowest possible latency similar problem that hfts trying to solve to make the highest profit.
Tag service
Design Food Deloivery App
Design food delivery app like UberEats, Doordash
Design Realtime analytics dashboard
Design LinkedIn
Design e-wallet
Deep Dive - Zookeeper
E commerce
SQL vs NoSQL
During the design which DB is best suited for the particular requirement and why ? Pros/Cons of it
Deep Dive - Neo4J / Graph Database
Google Maps
Design Facebook Live
Design a service to host a live streaming platform which can be used by anyone to broadcast live video to millions of users.
Deep Dive PostGIS (Postgres) & Geo Hashing (Redis) for Proximity Searches
Deep dive should cover quadtrees and base32 encoding used by PostGIS and redis.
Memcached vs Redis vs VoltDB
Dive deep into the choice of cache
Design a Rate Limiter
Design rate limiter puts a limit on the number of requests coming from a client/device to a service and throttles requests that cross the predefined limit.
Design alerting system
Design a system for the alerting which checks if the alert condition is being met. Scale can be across 1000s of services, each having 5 APIs, each API having 10 alerts (like reliability, failure counts, latency both percentiles and average) on avg.
Stock Price Alerts System
Design a system where a user can have X favorite stocks and has subscribed to their changes. Users will set some rules for price drop/ price rise above a threshold or % value and if the rule is satisfied then we have to send notification to the user
a feed aggregator
Create a feed aggregator that collects all social media into one combined feed
Deep Dives
Kafka vs RMQ when to choose
Design HTTP Resourcer/Downloader
Invetory tracking/management system
Deep Dive - What happens when you search google.com
A deep dive into the flow of how DNS are converted to IP and common networking related data.
Desing Location based Restaurant Recommendation
observability tool like datadog
Design Facebook i18n
Design stackoverflow
Design a Q&A platform like StackOveflow where users can ask questions, provide answers, upvote content, and earn reputation points
recommender system
Machine learning approach for folks interested in ML system design.
Design Quora/Reddit
Design a distributed auto increment id generator(should be ascending order)
Design wikipedia
Design Whatsapp or Facebook Messenger
Design IFTTT
Design a messaging queue like Kafka
Design ACL like Notion
In Notion ACL can be implemented on individuals, group of individuals as well as on pages where if a user has access to parent page then the user also has access to all the child/nested page.
sentry.io
Design a sentry.io like system
Continuous Integration System
Design amazon locker
Design of Amazon Product Review System
Design of Amazon product review system, write and read part especially during sale periods
Design real-time livescore sport
Like SofaScore, where Users can watch what is happening real time in a particular match. Taking care of important matches like World Cup Final or Super Bowl with inputs flowing manually or automatic from stadiums
Views and likes of a post in twitter(X)
Design a scalable system to handle the millions of views and likes of post in twitter. We should be able to scale for both read and write
Design Zillow
Phising detection system
Design a phising detection system
Phising detection system
Design a phising detection system
Online Stock brokerage
Design a telemetric service
All the services that are deployed in a organization can send their such as cpu/memory/ etc. These information can also be used by alerting/alarming service to alarm
Design Block Storage System .
I was asked this question within Amazon . The question is "Design a block storage system that can reduce the fragmentation of the disk and provide durable storage devices on demand" . Something like AWS Elastic Block Storage.
Design an ad serving system
Design a real time ad serving system for digital ads
Design a HighFrequency Trading Platform
Design a Marketplace System
Design multiplayer chess with leaderboard
Multiplayer chess system design - similar to chess.com, competition, leaderboard, etc.
Design Snapchat
main requirements : 1. sending of snap to one another/group 2. stories 3. snap score
Compiler
https://www.reddit.com/r/leetcode/s/9u0xAKryPI
Design Zoom
Design Common Components
Basically multiple design questions that explain how to design MQs or Blob Stores or Rate Limiters or Load Balancers...etc common components we would use in product design questions
Design ChatGPT
design LLm model using prompts. Emphasize on Scalability availability and how model should be trained
Design Instagram Story
Distributed File Transfer System
- Get one large file to thousands of servers in short time - System design specifically focused for Production Engineering role at Meta
Production Engineer System Design
- Design Problems asked in production engineering role - Doing OS upgrade in scale, automation etc
Design BrowserStack
Executing UI tests in multiple browser instances concurrently.
Metrics Monitoring and Alerting system
Metrics Monitoring and Alerting system
design a instagram
Upload, view posts able to send images and videos
Distributed counter
It has many use cases like: 1. Count of unique concurrent users logged in to a system 2. Count of a particular doc opened by user. 3. Count of likes on a post. The count value should be near real time.
Collabarative text edit like GoogleDoc
- collabarative text edit - simple styling - different type of clients
Design a real-time fraud detection system
Design a system that extracts transactional data, apply complex transformations (e.g. anomaly detection, pattern matching), and load results into a monitoring or alerting system in near real-time.
Design GitHub
Repositories' version control system
google maps
Design TrueCaller
Design like .mint app
Centralized System for Authorization
Design a central Authorization system that's capable of handling any combination of user(s)/entity/column level restriction centrally (similar to Google’s Zanzibar)
stock exchange
Design Reels
Design a Machine Learning System to prevent sales of guns through ads
There are not many staff level solutions for MLSD out there.
Design a Google Calendar
Design Stock Exchange
Instead of Broker App, design a Stock Exchange including Matching methodology.
Design S3 Blob Storage
Design online multiplayer game
Deep Dive Kinesis
Find shortes path between 2 users on linkedin.
Given 2 user IDs of users on linkedin. Find shortest path between the two. Assume that the shortest path won't be more than 4. This is similar to 1 degree 2 degree and 3 degree connection in linkedin.
Design logger
Design a Parking lot
Design a system to store images for FB and instagram that would require 100
Design perplexity
design hotel reservation system
Design CI/CD
Design Kafka
Design a Blob Store Lile AWS S3
Citi Bike
Design a bike sharing service like Citi Bike which could include the maintenance and docking stations
Design Zookeeper service
Design an eCommerce system like Amazon
Design backend of food delivery app like Doordash
design kubernetes
Design Zookeeper
Design OneNote/Google Keep
Sync notes across different clients Live editing & collaboration
Design a poker game
You're an online Casino offering some subset of gambling games to a large set of users. How would you design a system to support a wide variety of users, protect against fraudulent activity, and handle different types of regulatory constraints?
Design Datadog or equivalent
design an audit/event logging system
similar to pg_stat in postres. users should be able to find tables/columns used in time period. system should tell which columns/tables have not been used in time period t.
Design Just the UX and APIs for Newsfeed
Design Instagram Stories
Challenges in this particular problem: - Ephemeral - Ordering stories(latest first) - Paging for clients
Design authentication-authorization requests pipelines
System design - scale authentication-authorization requests pipelines for third-party vendors
Design FB Internationalisation System
You have an app and you want to design an i18n system for them. When the user changes languages, all the strings have to change to that specific language.
Design News Aggregator :
1. Fetch news Articles from multiple news publishers 2. Generate custom news feed for Users based on their interests and the publishers they follow
Design Event Tracking System like Amplitude
Create a scalable system for collecting, processing, and visualizing user event data. Include SDKs, reliable ingestion, efficient storage, querying, chart rendering, observability, error handling, and scalability.
Design a System for Event Processing and Querying
Build system to ingest, process, and store events (e.g., clicks). Support queries like histograms of clicks/hour over 24 hours. Ensure low latency, high availability, and design an SDK to handle server unreachability and traffic spikes.
Real-Time Data Processing Pipeline
Design a system to process real-time user activity logs (e.g., clickstreams, app interactions) and provide analytics in near real-time
Deep Dives: Apache Pulsar
Design Kubernetes
Design a container orchestration system for automating software scaling
Design a Large-Scale Image Rating Platform
Design a system where users rate images from a pool of 1M+ images. Each image needs configurable minimum ratings, no duplicates allowed. Focus on rating distribution, cost efficiency, scalability, and reliability. Handle spam prevention.
Deep Dive - ScyllaDB
Design Venmo
Can we talk about event sourcing and how does it fit in to a money transfer system, like Venmo. Users can transfer money between each other, and a delay payment, like scheduled payment.
Design Coursera
Deep Dive: Consensus Algorithms
Look into raft, paxos, multi-paxos, etc . Bonus if things like distributed transactions can be covered along with it.
Design Tik Tok / Instagram Reels
TRANSIT CENTER : MANAGEMENT
Design ATM
Basic ATM functionalities: Withdraw cash and update balance Deposit cash and update balance Check balance Deposit check and update balance Change PIN Update email, mobile number
Embedded system design for wifi team
My background is wifi. I would like to know about some system design ideas about the embedded system design.
Design Shazam
Design Machine Learning Systems
Design Gmail/Outlook
Email service
We list products and want to calculate sales and see top products sold ever
these are open ended questions which are asked
Design Cloudwatch
Instant web search
Design an instant web search engine like G Instant.
Design an IDE
Build a coding platform like intelliJ or Xcode that offers CI/CD, code editor, deployment automation tools, simulator, and supports multiple coding languages
Suggestion for Azure alternatives
I appreciate the valuable content, especially with AWS. It would be incredibly helpful if Azure equivalents were also included. This would support folks working with Azure and create a more well-rounded resource for all. Thank you for considering!
Design an HTTP interpreter for a web browser
Design a distributed linked list.
S3 Deep Dive
Would be nice to have a S3 Deep Dive, especially how to use S3 for object storage and use it at scale.
localization system
-Design a system that provides a localization feature for Facebook - the user creates a post in a language and has the option to translate that to other languages of his choice.
Discuss Queues
Apart from Kafka, it would be good to have deep dives on Rabbit MQ/Redis Pub/Sub, Amazon SQS etc
Deep dive - CDN
Design GoogleMeet
Online realtime video conferencing tool
Design Amazon
IoT Cloud
Large-scale infra for handling, collecting minimum 10 million devices data. For example building Connected Cars system using MQTT, Kafka, etc. Like any kind of devices can be registered and push the data to this cloud. Examples HiveMQ, EMQX, VerneMQ.
Design reddit
HTTP concepts relevant to system design
HTTP is a broad topic with plenty of content available. But, we see it dropped in guides on HelloInterview: where to put sensitive data? When to use headers? When to use PATCH?
Design a RAG application
Deep Dive - S3
A deep dive into a Blob store like S3 would be great. Pre-signed URLs, CDN via Cloudfront, ACLs, cold storage etc.
Design an event scheduler
Design a system for managing patient appointment scheduling, allowing for complex booking options (e.g., recurring appointments, multiple provider types, flexible cancellation policies)
Deep Dive - Mongo DB
slack
Design Twitch
Live streaming platform
Design an AI Agent
An artificial intelligence (AI) agent, or a system that can autonomously perform tasks on behalf of a user or another system.
Klarna System Design
Design Stadia like gaming service with top player leaderboards
Imagine that Youtube team would like to start advertising games before video begins. The ad will allow you play for 2 minutes and offer a link to purchase a game after that + leaderboards. Can you succeed where Google failed?
Design a location based service like Yelp
Get active events
System has handlers set_start(id, ts) and set_finish(id, ts). Incoming data via these endpoints are quite high. The finish event can come before the start event. What's the optimal way to calculate getActiveEvents(ts)?
Design Global Counter
Design youtube shorts
Design a therapy booking platform
like betterhelp or growtherapy
Design a build service for multi region cloud
Design Street View in Google Map
Design youtube likes
Users see likes on videos with low latency
design online Pong Game
players can join, and need to be matched with someone else who is online
Design a virtual agent
Design a virtual agent (retail/commerce/etc) which interacts with customers from a web or any other interface to understand the customer's questions and respond based on the company's or org's knowledge repository and any off the shelf LLMs (RAG)
Design Talent assessment platform & a resume screening/tracking system
Design Talent assessment platform like hirevue and a resume screening/tracking platform.
Design a Reminder application
Design a Traffic Light Control System for a city
Typo
Handling Big Data and Real-Time Web Apps: You have an applications dealing with large volumes of data, especially unstructured data, or applications requiring real-time data processing and analytics. an applications is wrong
Below looks not right. Could you confirm
Message Ordering: However, some queues (like Kafka) allow for more complex ordering guarantees, such as ordering based on a specified priority or time.
Design a hotel aggregator system where user can book a room
Design a social media application for introverts.
Design a ledger system
common question for fin tech, design a ledger system can record money movement and account balance.
Design Stripe/Plaid
Open AI
Internal company tool
placed in charge of a large application - runs in a single data center - all stored there and all processing serving and traffic is done there -multi data store -multi app server - serving diff portions of app design tool to monitor performance
Design code coverage tool
Design a centralized video update management system
Design a centralized video update management system that integrates with mu
Design figjam with multiplayer support
Figjam with comments and comment replies, with real time updates
Design a Bookkeeping System for Tracking Personal or Business Financial Tra
A bookkeeping system is used to record and manage financial transactions, such as income, expenses, and transfers. It helps individuals or businesses keep track of their financial activities, generate reports, and ensure accurate financial management
Designing a URL Shortening service like TinyURL
Design a Connector between Tiktok to its vendor like Amazon/Shopify
Design a Currency Converter
Distributed Key Generation Service
A system to support idempotency transactions.
Design VirusTotal
Users can upload file(s) to be scanned by multiple anti-virus engines and metadata scripts. Provide results close to real-time as possible. Scale to millions of users.
Stock Broking System
- Frequent update stock price which will reflects on Millions of end users - Order execution partially or fully - Event base order executions like Stop loss
Ebay Auction Site
Highly consistent, low latency and scalable system
design payload
Design LRU Cache
Design Live video streaming platform
System like hotstar which streams worldcup matches for 10 M users concurrently
Design notification system
How would you 90M followers of a celebrity that they are going live
Design Instagram story
Design Online Multiplayer Gaming Platform
Design Skype/Facetime
Design a service for the video call or conferencing between 2 or more users.
Design a zero-downtime data migration system
Intrigued by the logical replication section in the PostgreSQL deep dive, it would be interesting to see how data migrations are done at scale.
Design an online multiplayer game system
Design a voting system
users can cast multiple votes, latest vote counts. High accuracy vs low latency(real time) design
Metrics Agrregation system
Design a Logging System
Create an logging system with Application and Processing server
Design Fandango
Design backend for Fandango which provides functionality to book tickets with multiple providers. How do you manage locking?
Design TikTok
Design Alexa
Design clubhouse
Design a service to host audio conferencing between people for a scheduled event.
Design Message Broker like Kafka
Design a proximity Service
Design a counter service
Spotify
Design a sports betting Platform
Like Kalshi/Polymarket/BET 365
Design chess
Design Instagram Stories
Similar to designing something like a Facebook News Feed, but this time with handling photo uploads, story curation, and timing out / expiring of stories after some specified time.
Design a mobile image search client
Design a memcache
Design a cash/points back e-commerce aggregator system
Like LINE Shopping, Shopback
Weather app
Data modelling for system design
Writeup/ video on how to properly create a data model for your system
Design weather app
Design a vulnerability scanning platform
design a platform that we can updload different sources (binary, image, sbom, and container) to be scanned and generate vulnerabilit report to triage vulnerabilities to related teams.
Design online multiplayer game
Pastebin
How do you handle localization
Currently, on the server side, we have the below logic to handle localization. How do you scale up this switch title case "en-US" return "Welcome to Facebook"
Design card balance notification system
If balance drops below threshold notify user
Design fraud detection service
Design skyscanner
Given a service that returns flight deals for the last 7 days, design a system that surfaces relevant flight data to a user and notifies the user when there’s a new flight that matches their criteria
Distributed Job Scheduler - Kindly make it public
Design a logistic management system
Design a logistic management system like UPS, focusing on package CRUD, routing and tracking.
Telemetry Service
Process data from IOT
Design Facebook Status Update & Search
User is able set a status. 1 Status only per user. Design a third party api that can do a search on the status update.
discord
Design "Find My iPhone"
Functional Req: To be able to report my location To be able to see the location Max allowed lag 30 seconds Worldwide system 1B daily requests Follow up: "can you do (and should you) it with web sockets?" "dive deep into the DB design choices"
design chatbot
Design Fuzzy search feature
Design Amazon price notification system
Design Capcut
Design a video editing/manipulating service
Github Actions
Design a system like Github Actions which can run tests/actions in a scalable/configurable way.
Design chess.com or lichess.org
Design a system similar to chess.com (or lichess.com), which supports online chess games between users.
Design Waze
Design a real-time navigation system like Waze that provides optimal route planning by considering live traffic conditions, user reports, and GPS data.
Design Moovit (Transportation App)
Design a real-time public transportation app like Moovit that provides users with the best routes by combining static schedules and live GPS data, including multimodal transport (buses, trains, metro, etc.).
Design Moovit (Transportation App)
Design a real-time public transportation app like Moovit that provides users with the best routes by combining static schedules and live GPS data, including multimodal transport (buses, trains, metro, etc.).
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