I really like simple tools like this. Well done; I can see lots of uses for this, especially with the Serverless/Jamstack surge.

I love the idea of Hashing and read/write keys mentioned in this comment: https://news.ycombinator.com/user?id=miki123211

I also like the idea of batch requests so you can pul multiple keys at once, or set multiple keys at once. It seems better for everyone.

My only concern is that a small portion of users will undoubtedly try to abuse this with high volumes or large objects, or both.

Have you published any limits on value key size, value size, read/write limits for keys etc? It might be worth thinking about now before you have to shutdown users or shutdown the service due to cost.

Congrats again!