Interview questions
Real-time systemsMediumSDE-2

In your group chat, users sometimes see messages in different orders, and some see the same message twice after a reconnect. How do you guarantee ordering and no duplicates?

Asked at
Microsoft

Think first

Answer out loud as you would in the room — clarify, give numbers, name the trade-off — then compare with the model answer.

Saved on this device. Create a free account to keep it on every device.

Practise this with Sam

A real mock interview, out loud, with an honest scorecard. Free to start.

Start free