We've talked a lot about CoinJoins a lot throughout the years in this rag. For those who may need a quick refresher, a CoinJoin is the mixing of UTXOs of the same size in one transaction to obfuscate one's trail throughout the blockchain. Recently, a few idiots who ran a Ponzi scheme attempted to obfuscate their trails throughout Bitcoin's blockchain and pretty much checked off the list of everything you are NOT supposed to do when CoinJoin'ing.
Luckily for us freaks, Twitter user @ErgoBTC rolled up his sleeves and did some analysis of the blockchain to track these idiot thieves and point out where they went wrong.
Something that can never be understated is that Bitcoin's privacy assurances are extremely subpar at the moment. It is possible to transact privately, but it is extremely hard. CoinJoins help a bit, but must be approached tactically. One must consider where their soon-to-be-mixed UTXOs came from, how many UTXOs they are mixing at once using the same service, how many other individuals they are mixing with, where they send the UTXOs post-mix, how they deal with change after spending mixed UTXOs, and co-mingling post-mix UTXOs just to name a few variables. I could go on much longer. The only way to figure out how to do this correctly is to study. ErgoBTC's piece is some great homework.
Peep it. Grow your know.
Bitcoin ripping and Kanye dropping a new album at the same exact time really threw off my productivity. I predict these two forces of nature will only grow closer to each other throughout time.