I ehm. Don’t think so… I could be wrong tho

Not yet, at least I am not aware of such key rotation tech nostr today.

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Nsecbunker lets you manage your private keys through delegated child keys. I am running my bunker on a start-os server. It's a heavy lift currently and not all clients support nsecbunker login flow. More info here: https://www.nobsbitcoin.com/nsecbunker-announced/