user96549: I am writing a hardened Bitcoin node guide and I don’t fully understand the implications of pruning.
My understanding is that when one has a full copy of the blockchain, the node itself doesn’t reveal much about one’s UTXOs given everyone’s transactions are stored on the node (I believe same applies when using electrs).
Does pruning change something from a privacy perspective?

user48884: No. The privacy benefit is not because there is a local copy of the full blockchain but rather because full nodes receive and verify all blocks and transactions. This allows full nodes to determine what transactions belong to any wallets it is managing without having to ask anyone else for those transactions specifically. They receive everything, and so can filter what is needed from there. Whether that data is stored does not matter. The relevant transactions are stored in their respective wallets.
Pruning just affects how blocks are stored on disk. It is a node operation detail and not related to the wallet. Nodes with pruning enabled still receive and verify all blocks and transactions, and so any wallets being managed by the node will learn of their transactions. Blocks are still written to the disk - they just end up getting deleted eventually rather than staying permanently.

96549: <p>I am writing a hardened Bitcoin node guide and I don’t fully understand the implications of pruning.</p>
<p>My understanding is that when one has a full copy of the blockchain, the node itself doesn’t reveal much about one’s UTXOs given everyone’s transactions are stored on the node (I believe same applies when using electrs).</p>
<p>Does pruning change something from a privacy perspective?</p>
 48884: <p>No. The privacy benefit is not because there is a local copy of the full blockchain but rather because full nodes receive and verify all blocks and transactions. This allows full nodes to determine what transactions belong to any wallets it is managing without having to ask anyone else for those transactions specifically. They receive everything, and so can filter what is needed from there. Whether that data is stored does not matter. The relevant transactions are stored in their respective wallets.</p>
<p>Pruning just affects how blocks are stored on disk. It is a node operation detail and not related to the wallet. Nodes with pruning enabled still receive and verify all blocks and transactions, and so any wallets being managed by the node will learn of their transactions. Blocks are still written to the disk - they just end up getting deleted eventually rather than staying permanently.</p>
