NOSTR
Privacy on Relays
Your internet protocol (IP) address is exposed to the relays you connect to. If you want to improve your privacy, consider utilizing a service that masks your IP address (e.g. a VPN) from trackers online.
The relay also learns which public keys you are requesting, meaning your public key will be tied to your IP address.
Relays have all your data in raw text. They know your IP, your name, your location (guessed from IP), your pub key, all your contacts, and other relays, and can read every action you do (post, like, boost, quote, report, etc) with the exception of Private Zaps and Private DMs.
DM Privacy
While the content of direct messages (DMs) is only visible to you, and your DM nostr counterparty, everyone can see that and when you and your counterparty are DM-ing each other.
https://github.com/vitorpamplona/