pkt on Nostr: NIP-3 specifies how to use OpenTimestamps to timestamp events, proving they existed ...
NIP-3 specifies how to use OpenTimestamps to timestamp events, proving they existed prior to a point in time: https://github.com/nostr-protocol/nips/blob/master/03.md
But it may also be useful to prove events were created _after_ a point in time. The easiest way to do that would be to add a tag with a recent block hash to every event you create.
But it may also be useful to prove events were created _after_ a point in time. The easiest way to do that would be to add a tag with a recent block hash to every event you create.