When the user is offline, try send notifications to the user’s mobile device if a new message arrives.īesides the above features, the system should obviously be scalable and highly available.User status: whether you are online or offline.Typing indicator: when typing, the recipient gets notified.Join/leave groups, (add/delete friends not important for Slack).

Group chat: users can participate in group conversations.

Direct messaging: two users can chat with each other.For Slack (or other apps you use), the following features can be expected: Requirementsįirst thing first, we must figure out the exact requirements of the target system. In this article, I want to share with you my design of Slack, which is based on real-life interview feedbacks I received as well as discussions with senior engineers. As new grads/junior SDEa, we are good at implementation, yet designing whole systems is a challenge of its own kind. Personally, I’ve run into this problem a few times by now.

Introductionĭesigning chat applications like Slack or Messenger has always been among the top questions asked by system design interviewers. Ace the System Interview- Design a Chat Application 1.

Multi chat client python