System Design Interview Questions

Yag S. - "I studied Exponent's TinyURL system design video. My interviewer was asking many detailed questions on API design, schema, as well as data required to store. I found system design questions are bit high level instead of depth. I think should have detail design of API, schema and some additional flavors."See full answer

Kai W. - "The user awakes Alexa by saying the "Alexa word" Device starts recording audio from the user, and streaming it to the Alexa Cloud Service The recorded audio stream is sent to the ASR (Automatic Speech Recognition) system ASR returns the words and the order of the words in the audio stream, and sends this information to NLU (Natural Language Understanding) NLU returns the intent of the audio stream, and sends it to Alexa Skill If the intent triggers a "play" directive (e.g. turn"See full answer

Sri A. - "Mission: to help users buy and sell products from groups. If we think about the value here, users want to join groups that sell/buy products of interest (young moms or vinyl), or location of interest, or trust, or some other factor - either from other users or SMBs. User Actions: create groups, join groups, active in groups - make posts to sell or show interest in buying (like, commenting, sharing or ideally transacting) deeper engagement - sharing , saving , searching more based on wh"See full answer

James H. - "I broke the vehicles down by regions in the world. Designed a wireless api interface to sync with a database backend that linked to google maps through another service and api."See full answer

Ramesh Y. - "Clarification - is it Uber that is building the feature? Answer: Yes Assuming if Uber is the one building this feature, I would start with if and how does the feature help Uber's mission and north star metrics. Uber's mission is to provide reliable transportation around the world and the primary metric that i can think on a high level is Number of rides , Number of drivers and from business revenue perspective revenue per ride, revenue per rider and driver. I picked revenue per ride because it"See full answer

Bini T. - "I understand this is more focused on ML. However, I have a system question. If users allow us to access their location, or they send location via text box, could we use CDNs for the search without hitting our database? We only query the database when we have zero information on location. Other questions: does embedding always guarantee information on location? Do we discharge the user images after we return a prediction? I heard the feedback that we should keep it for future learning. What would"See full answer

Vishal B. - "Design an elevator for the blind Clarification Questions A person who is not able to see at all or a person who can partially see? - completely blind Are we we focusing on the people who are visually impaired but, no other physically challenge? - Yes Goal Company already have the elevator products and now company is trying to enter into new market space. Users Blind users with some assistance - we are not focused on these people as they already have some a"See full answer

Aditya O. - "Why is it answered like a Product Design Question? Shouldn't this be a strategy type answer analyzing the pros/cons of the service etc.?"See full answer

Ven E. - "I saw this question in one of my interviews."See full answer

Istvan K. - "Thanks you for sharing insight about the app which I would liek to summarize in 2 structures: functional 2 technical requirement. Requirements: Functional requirement: Able to share messages, siles , and other content like photos, sounds Create groups for conversaion Size: 500 million users, 50m DAU -> 500M active chats daily Files not stored in the system but is can be shared.. Integaration with other APPs Technical requirement: Availability: Can you help me to understand the a"See full answer

Rjj - "I tried solving this question and here is the recorded video for the entire solution - https://youtu.be/G_LIbTp58XA Feel free to comment here or on the video for further discussion."See full answer

Rashmi T. - "It depends on how computers are distributed. Are they located within same network (behind same switch or router) or distributed across globally? Also, it depends upon if there are any security related encryption or decryption algorithms being executed. Similarly, there are so many factors involved in it. However, if a system is highly responsive then this time might be less than 1 second. For example, any google search responds in less than 1 sec. It is an interesting question and I am eager t"See full answer

Satyajit G. - "It might not be a good idea to predict stock prices only based on reddit comments. You could create a signal from reddit comments that can indicate "social media interest" and feed it into a ML system (along with other features) that predicts prices. Collecting good data to train the model and evaluating it correctly are going to be huge challenges."See full answer

Abdurhman M. - "Start your stream Use the Post tab to: Choose where to post your live broadcast. Write a description. Select a camera, mic and screen (if screen sharing). Add a title for your live broadcast (optional). Select the primary language of the stream. ... Once everything is set, select Go Live."See full answer

Gk K. - " can we use blomfilters to check existing usernames? and if both are creating at a time, like both are choosing some abcd , here system checks whether user with that name exists or not. so while checking , it will add an entry on redis (example) with this name as key and obtain lock using some distributed lock. , it will lock on that name. (like seat booking in bookmyshow) with some TTL value. so this check will happen once user enters his interest username and also while submit .. 2 times che"See full answer

Claudia S. - "What is a "cache controller"? With no more details it's difficult to tell what this question is about."See full answer

Abhi R. - "TCP server/client to facilitate high throughput of incoming metrics.(This is the standard used in the industry by Datadog etc). NoSQL or timeseries database for storing metrics. Timeseries databases are better for aggregating metrics in a given time period. REST API for serving metrics data to visualization frontend."See full answer