A book by Wasim Ahmad
W H O H O L D S THE KEY?
An everyday guide to cryptography, passwords, crypto wallets, and navigating the technology that protects your privacy in the modern world.
Coming 2026 · 18 chapters · No math required
The book
You used cryptography fifty times before breakfast.
You unlocked your phone with your face. Paid for coffee with a tap. Sent a message that promised it was “end-to-end encrypted.” Every one of those moments ran on cryptography — the technology that protects your digital life, and the technology most people understand the least.
In Who Holds the Key?, technologist Wasim Ahmad explains, in plain English, the simple ideas behind the locks your life runs on. Through true stories and real-world examples — including the $1.5 billion theft where nobody stole the keys: the screen lied — he shows how encryption, digital signatures, passkeys, secure hardware, and cryptographic keys work, and why understanding them has become an essential life skill.
Built on four plain ideas and one master question — the one on the cover — the book runs from WhatsApp and Apple Pay to Bitcoin, AI, and quantum computing. No math. No jargon. No paranoia.
You don’t need to become a cryptographer. But by the time you finish this book, you’ll think like one.
Questions it answers
Every chapter opens with a question ordinary people ask — and closes with an answer you can act on the same afternoon.
Inside the book
About the author
Wasim Ahmad has spent decades where this book lives: at the exact point where deep, difficult technology meets everyday people.
It started early. As a schoolboy in Britain in the 1970s, he was among the first children to learn Prolog, the artificial intelligence language. He went on to the University of Sussex to study Mathematical Physics, then switched to Physics and French so he could spend a year in Paris — an early sign of a career that would keep crossing between the technical and the human. After university, he was an astronaut candidate with the Juno Project, but was too young to be allowed into space.
In the 1990s he joined Synon, the British startup whose software-based code generation won the Queen’s Award for Technology, moving with the company to Marin County, California. Then came the chapter that runs through the heart of Who Holds the Key?: as a founding member of Voltage Security, a Stanford University spinout, he launched the first commercial email encryption built on Identity-Based Encryption — the first genuine breakthrough in public-key cryptography in thirty years — working alongside some of the world’s most renowned cryptographers, including Stanford’s Dan Boneh. When catastrophic breaches hit the payments industry, he helped launch end-to-end protection for the world’s payment systems using format-preserving encryption, the elegant technique readers meet in Chapter 4.
His crypto journey began with AlphaPoint, working with the founding team that launched some of the world’s first cryptocurrency trading exchanges. He then joined Vault12, the pioneer of crypto inheritance, where the mathematics of Adi Shamir’s Secret Sharing — the scheme at the center of this book’s chapters on backup and inheritance — became a product that lets people pass their digital assets safely to the ones they love.
Most recently, he has been lobbying hard in both the United States and the United Kingdom — engaging with the SEC, CFTC and the FCA — to evolve the laws and regulations governing crypto, so that everyday people can access these technologies safely and confidently.
The pattern across all of it is the same one that drives this book: taking complex technology and formidable algorithms, and shaping them into solutions that ordinary people can trust, understand, and use.
Wasim lives in London and New York.