System Design Interview Questions
- 1of 1 vote
AnswersDesign a service that keeps track of mobile users as they check in at different locations. This service will get informed of each check-in in real time (a user/location pair) and must be able to answer the following queries in real time:
- Itcecsa June 27, 2017 in United States
1. Where is user U right now?
2. What users are at location L right now?
The following requirements apply:
1. A user can only be at one location at a time. If user U checks in at location X and then at location Y, they are no longer at location X.
2. A check-in only valid for at most 2 hours. If user U checks in at location X and then does nothing for 2 hours, they are no longer at location X.
The service should have durable enough storage that you can restart it without losing all of your data It should not store everything in memory.
what kind of DB will you use and how data will be organized and any indexes. If storage is spread out over multiple databases(locations), how is that done?
scalability/availability consideration, how will be distribute multiple servers. what happens when the traffic goes 10x all of sudden. What happens if one of the server goes down.| Report Duplicate | Flag | PURGE
AppNexus Software Engineer System Design - 0of 0 votes
Answersdesign an employee swap in swap out system.
- ashishsaraswat.iips June 26, 2017 in India
The system will have a machine which records the swap in and swap out.
The user can also login in a portal where he can check his swap in /swap out time. He can correct his time also.
There will be managers for employee who can check the entry for all the employees which are under them and correct their subordinates timings also
There will be HR who can only view the entries for all the employees.
We have to come up with the HLD and LLD for the system| Report Duplicate | Flag | PURGE
Amazon SDE-2 System Design - 0of 0 votes
AnswersDesign a message board system like Reddit were users can reply with messages on posted topics. How will you handle system scalability.
- ahmedthehack June 23, 2017 in UK for Amazon Video| Report Duplicate | Flag | PURGE
Amazon Software Engineer / Developer System Design - 0of 0 votes
AnswerSay there are 100K users. Each user object has certain details like city, credit score, gender ..etc
- Seeker June 01, 2017 in United States
Say there are 100 Campaigns, Each campaign has an entry criteria, meta data consists of email body / template and a rank.
Goal is to send an campaign email for each user per one day which matches the entry criteria. The email should have highest rank suitable for this user.
Ex entry criteria :- Gender should be Female, Credit score is 700-720 and San Francisco city. Typically the criteria can be combination of several things and involves different operators.
How would you design the system to find best campaign for each user and sends email?| Report Duplicate | Flag | PURGE
CreditKarma Staff Engineer System Design - 1of 1 vote
AnswersThere is a cluster of servers. In this cluster some group of servers are running application A, some group are running B, etc. Each application server produces huge logs and the log file sizes run into GBs. Each minute there are millions of log entries.
- Curious May 09, 2017 in India
You need to design a system that allows you to:
1. Specify the name of the application whose logs you want to search.
2. Search any text that the log message may contain.
3. Search within a time stamp range.
4. Search within the specified log level(s).
The system should be real-time.| Report Duplicate | Flag | PURGE
Amazon SDE-2 System Design - 0of 0 votes
AnswersGiven a large file with sentences and query string, design a system (Class, data structs, functions, etc) and algorithm to return the smallest window (start and end offsets) in the input file where the query words (in any order) are seen in the text file. What is the time complexity?
- Ray May 01, 2017 in United States| Report Duplicate | Flag | PURGE
Google Software Engineer System Design - 0of 0 votes
AnswersDesign a system which takes in latitude and longitude and returns back closest 5 locations.
- Ray March 26, 2017 in United States| Report Duplicate | Flag | PURGE
Facebook Software Engineer System Design - 0of 0 votes
AnswersDesign a conference room booking system for a company which can have offices in multiple cities, each city can have multiple buildings, each building can have multiple floors, each floor can have multiple rooms. Each room can have features like capacitiy, video conferencing available, etc.
- Vineet March 06, 2017 in India| Report Duplicate | Flag | PURGE
Amazon SDE-2 System Design - 0of 0 votes
AnswersDesign a kind of kindle fire application where we can subscribe news channel and read the news from all publishers as a digital format.
- Mihir.bhatt11 February 28, 2017 in United States| Report Duplicate | Flag | PURGE
Amazon SDE-2 System Design - 0of 0 votes
AnswersGiven the newest 100 entries of a person's facebook newsfeed. How would you rank the entries. The (for the user) most important ones should be ranked first. Which features would you use and how do you train/improve your model (machine learning)?
- nn862 February 28, 2017 in United States| Report Duplicate | Flag | PURGE
Facebook Research Scientist System Design - 0of 0 votes
AnswerDesign the architecture for advertisement platform where N number of advertiser can display their ad on M number of websites.
- avi.jasu01 February 22, 2017 in India| Report Duplicate | Flag | PURGE
Amazon Program Manager System Design - 0of 0 votes
AnswersDesign a system for implementation of stock market.
- jkjain.7884 February 17, 2017 in India
Buyer and seller case. stock server will receive buy request and sell request. A sell can be successful when it matches the quantity and price for same stock.
There will be many request for buyer and seller . Need to select the appropriate one.
Which data structure will be used ? how to handle concurrency issue?class diagram?| Report Duplicate | Flag | PURGE
Amazon Dev Lead System Design - 0of 0 votes
AnswersDesign an ATM machine system..
- TechPrep December 20, 2016 in United States| Report Duplicate | Flag | PURGE
Amazon System Design - 0of 0 votes
AnswersI was asked to design a stock ticker system. Stock ticker is simply the shortened name of company and its current stock size. e.g. for Apple - "AAPL" -> "115"
- 256.cool December 14, 2016 in United States
He asked me to design a data structure to store incoming stream of stock tickers. Stream can contain same company more than once but all the values of it had to be stored. I used HashMap<String, List<Integer>>. Then he was adding more functionalities to system I don't exactly remember the questions now but one of them was related to calculating some ratio in constant time. Some of the questions were challenging.| Report Duplicate | Flag | PURGE
Bloomberg LP Software Engineer / Developer System Design - 1of 1 vote
AnswersDesign a service to generate unique 64 bit IDs
- kanukadze October 18, 2016 in United States| Report Duplicate | Flag | PURGE
Amazon Senior Software Development Engineer System Design - 4of 4 votes
AnswersGiven that an external service gives a list of credit cards that have become fraud, design a fraud management system for a shopping website for bookings with fraud credit cards
- mesmerizing.memories123 October 14, 2016| Report Duplicate | Flag | PURGE
Amazon SDE-2 System Design - 0of 0 votes
AnswerYou have a web scraper that pulls car listing from Craiglist and other web sites. Design the system and API for the users to read the data.
- mrsurajpoudel.wordpress.com September 30, 2016 in United States
Follow-up : How will you scale your system?| Report Duplicate | Flag | PURGE
Triplebyte Software Engineer System Design - 0of 0 votes
AnswersDesign a cache for larger objects(>1MB) using memcached. You need to use API provided by memcached(which has constraint of not using more than 1MB of data per key). API are
- mrsurajpoudel.wordpress.com September 30, 2016 in United Statesmemcache.set(key, value) memcache.get(key)
| Report Duplicate | Flag | PURGE
Triplebyte Software Engineer System Design - 2of 2 votes
AnswersDesign a logging system. The system contains multiple application servers which are logging the information to file system. In this scenario, we want to check and alarm in case an exception is thrown in any of the servers. We want a system that checks for appearance of specific words, "Error", "Exception", "Disk Full" etc. in the logs of any of the servers. How would you design this system?
- jay September 17, 2016 in India
What if we want to scale the system in future?| Report Duplicate | Flag | PURGE
Amazon SDE-2 System Design - 2of 2 votes
Answers10000 cameras, 100 hours of video each. 30 fps. Police need to input a plate number and find the path of a suspicious vehicle. (Estimate the size of the video, e.g., blueray disc is 2 hours and 20 GB. No need to scan all of the videos. Estimate the time that a vehicle can be seen between 2 traffic cameras, e.g., 0.3 miles and 30 miles per hour, then select 1 out of 100). Web client, load balancer, servers, db.
- kwangrand July 31, 2016 in United States for Kindle| Report Duplicate | Flag | PURGE
Amazon SDE1 System Design - 0of 0 votes
AnswersThe following is the design question I was asked.
- gopi.komanduri July 26, 2016 in India
Design a dash board.
Should be very realistic.
Should be scalabe .
Should have very less latency .
Can expect millions of updates per second.
Dash board should show :
for each day :
1. city name ,
2.total trips in that city for that day ,
3.total fare it could collect in that city on that day,
4. fare collected from old clients
5. fare collected from new clients (new client is the client who is having his first ride in Uber after registration)
Input : we get two strings s1 , s2.
the format of s1 : trip_id , client_id , city , datetime
the format of s2 : trip_id , fare.
Could you please suggest how to proceed for this kind of question?| Report Duplicate | Flag | PURGE
StartUp Analyst Algorithm Business Question Cache Computer Architecture & Low Level Data Structures Distributed Computing Hash Table Ideas System Design - 1of 1 vote
AnswersHow will you design the news feed feature in Facebook?
- starsgazing June 04, 2016 in United States| Report Duplicate | Flag | PURGE
Amazon Software Development Manager System Design - 0of 0 votes
AnswersIn a customer support system how will predict number of support personnel requird on a given day?
- starsgazing June 04, 2016 in United States| Report Duplicate | Flag | PURGE
Amazon Software Development Manager System Design - 0of 0 votes
AnswersHow will you design the backend of product recommendor (You may also like these carousal) system on amazon.com
- starsgazing June 04, 2016 in United States| Report Duplicate | Flag | PURGE
Amazon Software Development Manager System Design - 0of 0 votes
AnswersYou have a cluster with 100 machines that need time to be synced. The central time server can only handle 10 requests at a time. How will you set this up?
- starsgazing June 04, 2016 in United States| Report Duplicate | Flag | PURGE
Amazon Software Development Manager System Design - 0of 0 votes
AnswersHow would you design search for a music streaming service?
- starsgazing June 04, 2016 in United States| Report Duplicate | Flag | PURGE
Amazon Software Development Manager System Design - 0of 0 votes
AnswersHow do you design a system for very large graphs(does not fit in a single machine)?
- Matt Chad January 31, 2016 in United States| Report Duplicate | Flag | PURGE
Google System Design - 0of 0 votes
AnswersYou have 10^9 user, 10^3 websites that users are subscribed to and 2000 servers. Some users will unsubscribe from certain websites. How would you architect this system to be scalable and performant?
- Ray January 20, 2016 in United States| Report Duplicate | Flag | PURGE
Google SDE1 System Design - 0of 0 votes
AnswersDesign auto complete for booking.com
- Qasim November 12, 2015 in Netherlands| Report Duplicate | Flag | PURGE
Booking.com Software Developer System Design - 0of 0 votes
AnswersDesign a train system which suggests shortest path and transfer needed to reach from source to destination. What can be the optimization.
- hm September 30, 2015 in United States
For example:
A system may have 10 trains from t1 to t10.
There are total 100 stops in the system s1 to s100.
Each train has fixed set of stops. You could allow to change and transfer train of source and destination does not cover using just 1 train.
What all can be APIs, data structure, optimizations scalable option.| Report Duplicate | Flag | PURGE
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