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There's some nitpicky bits (like how "utils.py contains two utility functions" is then followed by _three_ bullet points :P ) but one big one that jumped out was using "zrank" to get the new score.

That's not going to return the right value most of the time - for instance, in the example from the docs at https://redis.io/docs/data-types/sorted-sets/ has this:

    zrank hackers "Anita Borg" is 4

but "Anita Borg"'s score is 1949. The operation you likely wanted was "zscore".

It would be straightforward to check this, either manually or in an automated test - simulate hitting "/api/abc/" once and "/api/xyz/" three times. The result of 3 of the 4 requests will be wrong:

    for /api/abc/: will have count=0 because /api/abc/ is the only entry in the sorted set
    first one for /api/xyz/ will have count=1 because /api/abc/ sorts before /api/xyz/ and they both have a score of 1
    second one for /api/xyz/ will have count=1 because /api/xyz/ has a higher score than /api/abc/
    third one for /api/xyz/ will have count=1 because that's still true

Now, it's true that the assignment didn't say anything about what the service should return: you might have done better on this assignment by returning HTTP 204 and an empty body.

IMO when a "super senior / staff engineer" chooses to write code, they should write WORKING CODE and verify that that's true.

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docker exec -it flask poetry run http localhost:5000/api/abc/ docker exec -it flask poetry run http localhost:5000/api/xyz/ docker exec -it flask poetry run http localhost:5000/api/xyz/ docker exec -it flask poetry run http localhost:5000/api/xyz/

# - pipeline insures that the zincrby and zrank call happen atomically and prevents race conditions. # - zincrby increments the score on the string, zrank fetches the new score pipeline = redis.pipeline() pipeline.zincrby(URL_PATH_COUNT_DATA_STRUCTURE, 1, path) pipeline.zrank(URL_PATH_COUNT_DATA_STRUCTURE, path, ) data = await pipeline.execute() # returns the path and current count that was just made. return {"path": path, "count": int(data[0])}

- Why is there a pipeline here at all? - Why is it zranking? - Did the comment go stale and the candidate just has poor attention to detail? - Is the comment the candidate telling me that they don't know how zrank works and they don't know how pipeline works? - Why is the comment lying to me? - Does this super senior engineer think "insure" and "ensure" are the same word?