Hello @nathanbrown, that is a very good question ! That is indeed one of the thing I would to to archive.
In fact the API call is only executing a request on SteemSQL and returning the result in JSON format.
I had to use the API since SteemSQL now requires a paid account.
Like I said, this is on the list for future developments, I think it could be archived by using another source which would be public to execute the same query (probably not in SQL) and fetch the same data in a efficient way (not sure querying the blockchain directly would be efficient enough).
I would be really interested if you have lead I could follow on this.
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