Datomic as-of and since, in practice

 Considering we have a simple Datomic database, where we do 3 transactions:

First we add an app. Then we add a chat "c1" in that app. Then we add another chat "c2" in the same app.

Looking at the transaction history:

Now we can pull, at the different times of the transactions, using as-of meaning we'll only see the results as they were at that time:

But another interesting thing, is seeing the changes since a particular time using since (think you're asking only for changes since a particular time):