Tracers in the Dark

Andy Greenberg's Tracers in the Dark tells the story of how law enforcement and a handful of blockchain analysts discovered that Bitcoin is far from anonymous. Greenberg, a longtime Wired reporter and the author of Sandworm, follows the investigators behind the takedowns of Silk Road and AlphaBay and the case against the Welcome to Video child-abuse site, among others. The book reads like a thriller, but it is built on court records and interviews with the people involved.

Who it's for

Anyone curious about Bitcoin's privacy properties, from newcomers who like narrative nonfiction to long-time users who want to understand what chain analysis really can and cannot do. No technical background is needed: Greenberg explains addresses, clustering and mixers as the story requires.

What it does well

The central insight lands cleanly: a public ledger that records every transaction forever is a gift to investigators. Greenberg shows the heuristics behind chain analysis and the human work of patient detectives, tax agents and a small number of analysts, and he gives the criminals real personalities without glamorizing them. The pacing is excellent, and the book is a useful corrective to the idea that Bitcoin is untraceable.

Where it falls short

The perspective is largely that of the investigators, and the book is relatively uncritical of the tools they use. Questions about the accuracy of chain analysis, the privacy of ordinary users and the power of firms that sit on top of the ledger get only brief attention. Readers interested in the privacy-tools side of the debate will want to pair it with other sources. It is also a book about crime, so it covers little of Bitcoin's monetary or technical case.