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devcon 5 / a trustless ethereum mixer using zero knowledge signalling

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A trustless Ethereum mixer using zero-knowledge signalling

Duration: 00:19:08

Speaker: Barry Whitehat, Kobi Gurkan, Wei Jie Koh

Type: Breakout

Expertise: intermediate

Event: Devcon

Date: Invalid Date

Since Ethereum transactions are fully visible on-chain, it is possible to trace value transfers and surveil users' financial activity. This state of affairs deprives users of privacy beyond mere pseudonymity. Some workarounds, like using a centralised exchange wallet or a custodial mixing service, however, introduce a high degree of counterparty risk. The Ethereum ecosystem needs a noncustodial mixer which works through strong cryptography, rather than blind trust. To solve this, we present a trustless mixer for Ether and ERC20 tokens. It builds upon Semaphore, a zero-knowledge signalling system by Barry WhiteHat and Kobi Gurkan. Additionally, it employs a burn relay registry which incentivises third parties to pay gas fees on behalf of mixer users. In this presentation, I will show a high-level architectural overview of the mixer, dive into its underlying zero-knowledge circuits, and discuss other applications of zero-knowledge signalling.

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Privacytechnical
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