A unique feature of the new BTCPay coinjoin plugin is payment batching in coinjoins. How does it work and why is it important? A thread 🧵👇
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Sending payments directly within a coinjoin provides better privacy and lower fees than sending payments using outputs you received from a coinjoin.
When users make a regular payment, a change output is created unless the sender can add up the exact amount they are trying to pay using the inputs in their wallet. Wasabi Wallet makes this calculation easy by suggesting to pay slightly more or less to avoid creating change. This potential waste can be eliminated if a user is willing to wait for a coinjoin round to be coordinated when making a payment. Batching cuts out the extra step, revealing even less information about their balance to the recipient while saving transaction fees.
By making a payment within a WabiSabi coinjoin, any change amount returned to the sender that would ordinarily be trackable gets broken down into private amounts that match other users in the coinjoin instead. This prevent recipients from knowing that the sender has any additional coins left in their wallet. Single participant transactions can only match this privacy property if their tx doesn’t create any change at all, which requires some amount of luck.
Payments within coinjoins also reduce the total amount of blockspace required for the coins to reach their final destinations, reducing the amount of transaction fees paid. No intermediate outputs are created just to be immediately spent to a new recipient.
Simply having the capability to make payments in a coinjoin improves the privacy for all coinjoin participants, even if the coinjoin doesn’t actually contain any payments. This is because observers trying to track the addresses of users can’t be certain that the outputs belong to the original coinjoin creators, since an output can potentially be sent to a non-participant.
Learn more about the BTCPay coinjoin plugin: https://blog.wasabiwallet.io/wasabiwalletxbtcpayserver/
wasabiwallet / Wasabi Wallet
npub167…8schc
2023-03-06 13:38:25
Author Public Key
npub167hmfzj38hkumks4wxny89797la0sf7wnwfrw4enlmcl82msp0cs78schcPublished at
2023-03-06 13:38:25Event JSON
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"kind": 1,
"tags": [],
"content": "A unique feature of the new BTCPay coinjoin plugin is payment batching in coinjoins. How does it work and why is it important? A thread 🧵👇\n----------------------\n\nSending payments directly within a coinjoin provides better privacy and lower fees than sending payments using outputs you received from a coinjoin.\n\nWhen users make a regular payment, a change output is created unless the sender can add up the exact amount they are trying to pay using the inputs in their wallet. Wasabi Wallet makes this calculation easy by suggesting to pay slightly more or less to avoid creating change. This potential waste can be eliminated if a user is willing to wait for a coinjoin round to be coordinated when making a payment. Batching cuts out the extra step, revealing even less information about their balance to the recipient while saving transaction fees.\n\nBy making a payment within a WabiSabi coinjoin, any change amount returned to the sender that would ordinarily be trackable gets broken down into private amounts that match other users in the coinjoin instead. This prevent recipients from knowing that the sender has any additional coins left in their wallet. Single participant transactions can only match this privacy property if their tx doesn’t create any change at all, which requires some amount of luck.\n\nPayments within coinjoins also reduce the total amount of blockspace required for the coins to reach their final destinations, reducing the amount of transaction fees paid. No intermediate outputs are created just to be immediately spent to a new recipient.\n\nSimply having the capability to make payments in a coinjoin improves the privacy for all coinjoin participants, even if the coinjoin doesn’t actually contain any payments. This is because observers trying to track the addresses of users can’t be certain that the outputs belong to the original coinjoin creators, since an output can potentially be sent to a non-participant.\n\nLearn more about the BTCPay coinjoin plugin: https://blog.wasabiwallet.io/wasabiwalletxbtcpayserver/",
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