Design Twitter - System Design Interview

0:00 - Context
0:24 - Requirements & Goals of the System
1:09 - Functional Requirements
2:16 - Non-Functional Requirements
3:16 - Capacity Estimation
5:37 - Flow of posting a Tweet
6:24 - Building the Newsfeed
8:11 - APIs
9:41 - Delivering a Tweet - Push vs Pull
12:23 - Fanout Service - Deep Dive
16:20 - Building the Newsfeed - Deep Dive
18:11 - Search Service
20:18 - Trending topics
20:48 - Data Partitioning
21:52 - Ranking Tweets at Scale
22:53 - Conclusions

[pietraderdetective]

You delivered amazing amount of knowledge with crystal clear explanation within such short duration..awesome!


Great content Sir!

[ericpuffs]

Really high quality content among all system design channel! You know exactly what you are talking about! But would you increase the volumn for all your future video?

[imichaeli]

Top level content, would love to see more!

[DK-oxze]

Great video. However it's not clear how the pull mechanism will work efficiently when a user is subscribed to lots of celebrities? In that case the server will have to query multiple shards at query time, which is not efficient.

[azharuddin]

Hi, really like your content. The only question I have is that in the cache, does user_id refers to the id of the person who made the tweet? Tell me if I'm getting this right: Whenever a user wants retrieve newsfeed we get ids of all the users that this particular user follows from graph database, then use those ids to pull out the tweet_ids that corresponds to those user_ids (so that we only pull tweets were made by the users that this user is following) from the newsfeed cache, then pull out user info from user cache and finally use tweets_id to pull out tweets data from tweets cache. Is this how it works?

Would really appreciate your reply! I'm really confused about the mapping between tweet_id and user_id, does the user_id refers to the id of the user who made the tweet?

[beopinioned]

It's definitely a very good content

[ritwik]

Can you make more videos on frequently asked system design questions