Thank you, great info!
It will be interesting to see a prod deployment of cashu from a high-throughput wallet service like wallet of Satoshi; geo-redundancy with high write through put db like dynamodb or Cassandra.
Discussion
I'm pretty sure that the mint I've built uses less resources than an ordinary table with transaction logs. We also started thinking about this from the beginning and implemented key rotation, which enables you to drop the db altogether every couple of months or years, after the rotation is finished.
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