Tried a design problem of Amazon’s sales rank by category feature
2 min readMar 16, 2024
I tried this problem. I could learn some points and summarize them.
My answer
The sample answer
The points I missed are below.
・Sales rank service
I had it in my mind, but I didn’t write it. I should have written it because it has a comparatively big class object, which means it is a feature.
・ObjectStore
Necessary for storing logs of sales.
・Queue
Queue is not necessary. At first, I added it because calculating the rank would take much time. However, the rank is calculated, using logs in the object store. That’s why, queue can be left out.
・Cache
If the service require an availability, it should be included.
However, my answer and the sample answer look similar. I’ll keep improving my design skills!
