I do this with a side project, except it's SQLite databases on s3 buckets -- that's about as easy as it gets and doesn't require nearly as much of the configuration overhead that Aurora does.
I wouldn't trust it for write concurrency but it's been great for my use case (reads are multiple orders of magnitude more frequent than writes; and the writes can be queued), I'm using s3sqlite for this from the Zappa project: https://github.com/Miserlou/zappa-django-utils/blob/master/z....
How about performance? How much time to read from the database?