Thread by @ODELL

1/6 A lot of confusion due to the wasabi team putting out vague tweets about blacklisting rather than a proper statement and this poorly written block article below that is being shared widely.

- coinjoin is not a mixing service, it is a type of collaborative bitcoin transaction

2/6

- a coinjoin is a native bitcoin send transaction that includes multiple users in a non custodial transaction that attempts to break the probability analysis chain surveillance firms use
- there are multiple software implementations that can construct coinjoin transactions

3/6

- wasabi is one of these software implementations
- it relies on a centralized coordinator that builds transactions and is accessed via Tor
- coordinator cannot link inputs with outputs, without an active attack (see #6), but can prevent inputs from participating in rounds

4/6

- wasabi defaults to a coordinator that is run by a company called zkSNACKs
- this coordinator is now blacklisting certain utxos from participating in coinjoin rounds
- anyone can run a competing coordinator that does not do this blacklisting and users can switch to it

5/6

- samourai whirlpool and chaincase also use a centralized coordinator model
- their coordinators are not blacklisting utxos
- there are coinjoin tools that do not use centralized coordinators, including samourai stonewall, stowaway, and joinmarket

6/6

- centralized coordinator models do not have sybil resistance against the coordinator themselves
- this means that if they choose to actively flood rounds with bitcoin they can potentially link inputs and outputs
- more info here:

https://twitter.com/ODELL/status/1297977489424371714