System Design Interview Questions

Anonymous - "Functional requirements: (a) location tracking (b) check-in at nearby place (c) view historical checkins with how much time user stayed there (d) Mark checkout when out of proximity (e) analytics - checkins by user at given loc, top n places Out of scope: (a) checkin sharing with followers Non functional: (a) low latency (b) high availability (c) eventual consistency Scale: (a) QPS: 10M DAU * 2 checkins /86400 seconds (b) Yearly Data Volume: 10M* 0.1 KB *365 days HLD: user -> location servic"See full answer

Rahul J. - "Clarifying questions Target geography: USA, all urban areas Form factor: Mobile app, supported on iOS and Android Items to be borrowed: simple appliances like toaster, FMCG products, etc. Target market USA has a population of millions of people People generally need to frequently borrow household items from neighbours in case of emergency (or even otherwise) Internal company assessment Meta's mission is to create communities that help each other. This problem ties in well with t"See full answer

Exponent - "This is a Design a Product question. For this, we'll want to follow the formula for success: Ask clarifying questions Identify user types, behaviors, and pain points State the goal and use cases List current solutions Improvements / net new solutions Evaluate and select solutions Measure Success Summarize Ask clarifying questions The PM interview isn't about your ability to come up with the best solution right away — it's about bein"See full answer

Brandon C. - "We can start by considering the key components: waiters, tables and customers. We'll need a database to store information about waiters, tables and customers, each waiter can have a unique ID and we can track the. number of tables they are servicng. Tables can have attributes like table number, capacity, and current status. Customers can be tracked by their arrival time and party size. we can calculat ethe expected waiting time bu considering the average time a table is occupied and the number o"See full answer

Praveen V. - "to clarify, there is nothing specific about FB email. you expect all functionalities of typical email program like msft/google etc assume there are no restrictions. i.e. not restricted to use within FB only As always, fb has great suite of tools to bring people together and build community. its only natural that if i have fb account why not i have FB email address.... assume its a new product, they we need to acquire and engage users and then think about retention this case..... for any produ"See full answer

A S. - "Clarified with interviewer: How it is used ? user will give facebook page of school as input What is the criteria for declaring school as duplicate ? same name and location used exposed APIs of parent service to create and maintain a inverted index [msg queue+spark]. Duplicate matching service will use elastic search [and filter out input school page]. Elastic will search and return results of school name and geospatial matching ."See full answer

Sangeeta P. - "Since I am residing in Bangalore, I will consider the Bengaluru airport. The airport has 2 terminals. I am going to consider the security scan done at both the terminals for the estimation. Does it include security scans for both international and domestic flights? --> Both The airport crew members and pilots also go through the security scan. So, should I include only them as well or only the passengers in my calculation? --> Only the passengers Number of people going through the security scan"See full answer

Priyanka C. - "Firstly need to check is this service really beneficial or not. And video service provide more realistic perspective about the product so keep it"See full answer

Abdurhman M. - "To determine what predictions to show, our systems look for common queries that match what someone starts to enter into the search box but also consider:"See full answer

Ayo A. - " Broke down the problem in this: Features scope API design Pseudo code for specific components Data model/schema Back-of-the-envelope calculations Reference links Link to whiteboard or diagram such as https://sketchboard.me/new Good luck! Considerations: Content could be potential large Older content should clean from the server URL: Pastebin.com/2324234 Features Scope: user can paste any text content .TXT, .HTML Limit on the amount content compress data and send over"See full answer

Rahul M. - "We should define automated Scheduled Updates for deployment to keep the application up to date."See full answer