#messaging

6 messaging interview questions, asked at Google, Anthropic, Waymo. Last asked Oct 2026.

One-on-one chat system with presence and offline queueSystem designDesign direct messaging for single-device users: delivery, presence, offline-recipient queueing, session storage, and the choice of message bus. Group chat is explicitly out of…
Last asked Oct 2026
Design reliable command delivery between autonomous vehicles and the cloudSystem designDesign how commands are sent between the cloud and a fleet of autonomous vehicles (and acknowledgements back), so a command is delivered and acted on exactly as intended even with…
Last asked Aug 2026
Design customer support with handoff from virtual agent to humanSystem designUsers chat with a virtual agent and can be escalated to a human support agent. Design the system with the focus on the handoff: how the conversation's context goes with it, who…
Last asked Jul 2026
Design a replay system for publish-subscribeSystem designPublishers send messages to subscribers through a pub-sub system. Design a replay feature that lets a subscriber receive past messages again from a chosen point. Cover how…
Last asked Mar 2026
Design a high-throughput publish-subscribe event systemSystem designProducers publish events on topics and many subscribers receive the events they subscribed to. Design it for very high throughput: subscription management, fan-out, delivery…
Last asked Sep 2025
Design school-to-guardian messaging with acknowledgmentsSystem designA school sends messages (announcements, alerts, notes about a student) to parents and guardians, who must acknowledge important ones. Design delivery over several channels…
Last asked Sep 2025