Asked to implement a feature in a mobile app that wasn't actually supported by the backend. Feature had 3 possible values in the backend, only 1 and 2 were properly implemented. Below was the backend teams solution to support the third option.

- If the key is missing in API response A, means the user is not allowed access this feature.
- If the key is present in API response A, and missing from API response B, that means it hasn't been set.
- If both are the same value, user has that value.
- It will never be the case that both return option 3.
- If both are different values, one of them being option 3, display option 3.

this ... monstrosity, is in production to this very day.