Replying to Avatar sommerfeld

Coinjoin is not about protecting the source of the utxos but the destination.

It hides your spending.

If you have 100% no-kyc (good for you, you absolutely should), and spend 1 btc on a car, use that change and spend 1M on a gun, the person you bought the car from can figure out you bought a gun.
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Diacone Frost 1y ago

Isn't that a payjoin?

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Diacone Frost 1y ago

*payjoin csse

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sommerfeld 1y ago

A payjoin is just a special kind of coinjoin done with the merchant. The merchant obviously knows how to unmix it, so it does not protect you from him specifically.

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Diacone Frost 1y ago

I'm sorry but I don't see the "obviously" part. can you help me to understand that?

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sommerfeld 1y ago

Sure thing. If you participate in a 2 person coinjoin, you can "obviously" unmix it since you know what inputs and outputs are yours (the remaining ones are form the other participant).

So if you use payjoin with a merchant, you gain privacy from 3rd parties (chain analysis, criminals, IRS, etc) but you gain no privacy from that merchant itself, since he also is participating in the coinjoin.

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Diacone Frost 1y ago

payjoin with two people is funny.

but I get it. the problem is when there is a change. then you have to mix it. Or you only spend in payjoin mixes. Or am I missing something?

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Diacone Frost 1y ago

omg. probably the same thing 😂