NIP-0A - Contact List v2

0A.md

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+NIP-0A
+======
+
+Contact List v2
+---------------
+
+This is an early draft, I'll flesh out details after discussion.
+
+Event tags would look like this:
+
+```
+    ["contact", "<pubkey1>", "in", "<timestamp1>"]
+    ["contact", "<pubkey2>", "out", "<timestamp2>"]
+```
+
+Note that they are not 'p' tags, they don't need delivery to the person's INBOX.
+But maybe they should be searchable to people can count their "followers".
+
+When you add a person, you find their entry and change the last two fields to "in" and the current timestamp.
+
+When you remove a person, you find their entry and change the last two fields to "out" and the current timestamp.
+
+When merging two events, you accept the entry with the largest timestamp.
+
+Note that we have to keep the "out" entries in case we later get an "in" entry dated earlier, we can
+ignore such an add.
+
+This is functionally implements a Last-Write-Wins Element Set, which is a conflict-free replicated data set
+with eventual consistency.