Whatsapp

This blog is written as per the codekarle system design series. 

FR:

• One to one chat

• Group chat

• Text, images, video

• Read receipt

• Last seen

NFR:

• Low latency

• High availability 

• No lag

• Scale

  • 2 Bil users

  • 1.6 Bil Monthly users

  • 65 Bil msgs/day