Design DoorDash
Take a food order, get a restaurant to cook it and a courier to arrive just as it is ready, and keep three parties in sync across millions of orders a day.
One question on this site is reported in Instacart software engineer interviews. Each has a full reference design (requirements, back-of-envelope numbers, components, user flows and deep dives with interviewer follow-ups). Each one can be walked through turn by turn and then sat as a mock. Patterns covered: state-machine, dispatch, eta-prediction, location-tracking, marketplace.
Attribution comes from public interview guides and candidate reports, not from Instacart. It indicates where a question has been asked, nothing more.
Take a food order, get a restaurant to cook it and a courier to arrive just as it is ready, and keep three parties in sync across millions of orders a day.
Large-company loops run 45 to 60 minutes, expect numbers, and spend most of the time on deep dives. Walk through a question to see how a strong candidate paces the hour, sit the same question as a mock until you can produce the requirements, the estimates and the design without looking, then read the interview framework guide for how to structure the hour. The other questions on the site teach patterns that show up in Instacart interviews under different names.