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# HushDEX
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HushDEX forked from the Subatomic Decentralized App (dapp) and we focus purely
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on privacy coin swaps, and specifically, shielded swaps between Zcash Protocol
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coins. These are called z-swaps.
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## Z-swap example
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Alice has 1 ZEC and wants to trade it for 5 HUSH, since she hears HushChat is
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pretty awesome and ZEC just goes down in price, always. We represent this in
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a diagram like this
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Alice (ZEC) <> Bob (HUSH)
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HushDEX is only concerns with Sapling shielded addresses (zaddrs) which start
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with `zs1`. Even though ZEC supports Sprout addresses (which start with `zc`),
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they cannot be used on HushDEX. Sprout is unsupported on HushDEX.
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So Alice must make sure her ZEC is in a Sapling zaddr, and then she can use
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HushDEX on her computer, to z-swap with Bob, in a decentralized way, with
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no centralized service. The system is not completely trustless, users must
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trust the developers and miners on the relevant chains to not do nefarious
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things. There is no central authority to decide who gets to do what, it's
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peer-to-peer like BitTorrent or Tor.
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## Privacy Features of Z-Swaps
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* No KYC
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* We will not feed the identity theft industry any more free data
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* No IP address limiting
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* It is trivial to pay for an IP address from any country in the world
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* Alice's blockchain address never appears in public data
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* Bob's blockchain address never appears in public data
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* Consequently, Alice and Bob's address cannot be searched for on an explorer
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* Since you can't see the address of any transaction, you cannot infer if
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the same address appears as sender or receiver in many transactions.
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* The amount of the transaction, how much ZEC and how much HUSH, is unknown
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* It could be pennies or millions
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* The exchange rate of the transaction never appears on the blockchain
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* The exchange rate will be leaked to the network p2p layer, but it is never
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recorded in blockchain history. If you are not there to record it, it is gone.
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* Realistically, it's simple to run a malicious node which records all exchange rates
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and so we assume an adversary does this
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* Since the exchange rate of ZEC/HUSH is already public data, this is not considered valuable
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information leakage. We are leaking the differential of CEX ZEC/HUSH exchange ratio to
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this DEX's ratio.
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* Adversaries watching all possible public data can infer exchange ratios but no amounts
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or addresses, which is considered a massive blow against blockchain analysis.
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