Kukks / Dumplings

A cross platform and open source software to create reproducible CoinJoin statistics from Blockchain data.

Setup & Run

1. Get Git: https://git-scm.com/downloads
2. Get .NET Core SDK: https://www.microsoft.com/net/download
3. Get Bitcoin Knots: https://bitcoinknots.org/
4. Make sure your bitcoin.conf has the following entries: txindex = 1, server = 1, rpcuser = user, rpcpassword = password, listen = 1, rpcworkqueue = 128
5. Run Knots and wait until it's synchronized.
6. git clone https://github.com/nopara73/Dumplings.git
7. cd Dumplings/Dumplings.Cli
8. dotnet run -- sync --rpcuser=user --rpcpassword=password

Usage

1. Run Knots, wait until it's synchronized.
2. cd Dumplings/Dumplings.Cli

1. Synchronization

In order to run other commands and local storage to be up to date you have to synchronize Dumplings. You can synchronize it with the sync command. This will go through the blockchain and find and save transactions that other commands work with.

dotnet run -- sync --rpcuser=user --rpcpassword=password

If you want to resync, then use the resync command.

dotnet run -- resync --rpcuser=user --rpcpassword=password

2. Integrity Checks

After you synchronized you probably want to do some data integrity checks too:

dotnet run -- check --rpcuser=user --rpcpassword=password

3. Creating Statistics

The software can create statistics after it synchronized. Synchronization will create a folder, called Scanner and some files in it:

From these files you can create many kind of statistics quickly or just create the existing statistics. You can download a Scanner folder that's synced up to 2020-05-22 from here.

The expected location of the scanner folder is Dumplings\Dumplings.Cli\bin\Debug\netcoreapp3.1\Scanner on Windows and Dumplings/Dumplings.Cli/Scanner/ on Linux (and probably on OSX.)

After synchronization you can create statistics as follows: dotnet run -- COMMAND --rpcuser=user --rpcpassword=password, where the COMMAND is the command for the statistics you want to create.

Commands & Results

MonthlyVolumes

Total monthly volume of CoinJoin transactions.

FreshBitcoins

Best proxy for user adoption.

How many non-remixed bitcoins get to CoinJoined monthly.

Average count of remixes is a derived metric, which shows how many times a bitcoin participated in mixes in average: total volume/fresh bitcoins.

NeverMixed

Bitcoins those were intended to be mixed, but were not.

• For Wasabi and Otheri, it counts CoinJoin change outputs those have been spent, but not in other CoinJoins. (Note 1: the software does not currently examine if the change is coming from CoinJoined inputs. Note 2: more related metrics and more detailed explanation on Wasabi's inefficiency can be found under the WasabiCjEfficiency repository.)
• For Samuri, it counts TX0 transaction outputs those have been spent, but not in other TX0 or Coinoin transactions.

The following is a derived metric: it's the percentage of nevermixed coins to fresh bitcoins.

CoinJoinIncome

Note: Without sophisticated algorithms it is hard to tell how much income Wasabi makes after it changed its fee address to dynamic calculations, so that's why the data is discontinued at some point.

The next is a derived metric. It's the percentage of monthly income where the total is the fresh bitcoins coming into mix monthly.

PostMixConsolidation

Average number of inputs in the first non-coinjoin transactions after coinjoins.

SmallerThanMinimum

Percentage of inputs those are smaller than the base denomination in Wasabi coinjoins.

FAQ

What does Wasabi, Samuri, Otheri mean?

• Wasabi: Wasabi Wallet ZeroLink CoinJoins.
• Samuri: Samourai Wallet Whirlpool CoinJoins.
• Otheri: Other CoinJoin looking transactions.

What about JoinMarket?

JoinMarket transactions are not obvious to identify with high accuracy solely from Blockchain data. To identify JM transactions one would need to listen to JM orderbook, which is off-chain data, so that is outside the scope of Dumplings. BlockSci made the best known attempt to identify them, which had only a 94% accuracy rate, which included computationally expensive subsetsum problem solving and left out larger JoinMarket transactions. Leaving out larger JM transactions would lead to misleading results and graphs, so I opted to not do that.

In summary: Every JoinMarket transactions are "Other CoinJoin Transactions," but not every "Other CoinJoin Transactions" are JoinMarket transactions.

What about network level privacy?

Not all CoinJoins are created equal. Statistics like this gives the wrong impression that a Samurai CJ is just as good as a Wasabi or a JoinMarket CJ. This is not the case. Just like Blockchain.info's SharedCoin CoinJoins weren't, Samourai CoinJoins aren't trustless either, as these companies know your xpub, from which all your present, past and future Bitcoin addresses can be derived, thus users gain no privacy against these companies and the third parties they share your data with, even if they CoinJoin.