Bitcoin Forum

We have seen these different approaches done to anonymize transactions in the past. But as they begin creating it, we also mostly see the developers having difficulties of reaching their goals, and the project usually fades and are left unfinished.

Let us hope this project will not be another form of masternode system.

http://media.coindesk.com/uploads/2017/05/marble-jar-300x185.jpg

Running such a system on ethereum opens up the possibility of both leveraging the platform's smart contract functionality and eliminating the need for a trusted third party to handle the mixing, as is currently the case with bitcoin mixers.

As the zcoin post explained:

"Unlike Coinjoin and its variants, it also does not require a central server to process such mixing, does not require you to trust any third parties and does not require other users to provide liquidity for a mixing transaction."

Read in full http://www.coindesk.com/a-decentralized-coin-mixer-for-ethereum-zcoin-is-working-on-it/

if I understand it right this needs smart contracts availability so rootstock is the way to go forward with the implemetation of it for a decentralized mixer for Bitcoin.

https://zcoin.io/zcoin-implement-zero-knowledge-proofs-ethereum/