System requirements

Functional:

Needs to return urls

Non-Functional:

Urls should be pretty

Capacity estimation

Probably pretty big

API design

Retrieve url

Database design

See diagram

High-level design

A lot of components

Request flows

No idea

Detailed component design

That is asking a lot

Trade offs/Tech choices

No trade offs

Failure scenarios/bottlenecks

It just works

Future improvements

Maybe spend more than 30 seconds on it