Latest News: Added Improving Multisig Custody with Request & Response (2/28/24).

“The use of advanced cryptographic tools to improve the care, maintenance, control, and protection of digital assets.”

Our goals:

  1. Raise the bar on best practices for digital-asset custodianship by building a greater understanding of different custody use cases, risk models, and adversary analyses.
  2. Prepare for newer custody technologies that break older models for custodianship.

#SmartCustody is a project of Blockchain Commons, who advocates for the creation of open, interoperable, secure & compassionate digital infrastructure to enable people to control their own digital destiny and to maintain their human dignity online.

The Book

#SmartCustody supports our shared blockchain infrastructure, improving the security of cryptocurrencies, identity wallets, and other digital assets. The first edition of our book on the topic is now out, covering the topic in 186 pages. Thanks to our early patrons, this first edition is free: you can download a PDF or you can get a hardcopy from Lulu at cost.

#SmartCustody Contents

I. Risk Modeling
II. Cold Storage Self-Custody Scenario
III. Adversaries
IV. Digital Custodianship Responsibilities
V. The Frank Family Fund Example

Download the Book
Order a Print Copy

We are also preparing to work on the second edition of the book, which will dramatically expand the content and include new hardware wallets, a multisignature scenario, and information on fidicuary multisigs. You can help us realize this new edition by becoming a sponsor, either as a recurring patron at GitHub or by supporting #SmartCustody with Bitcoins through our BTCPay. Let us know that it’s #SmartCustody that interests you!

The Articles

In advance of the new edition of the book, we are also researching and publishing other articles on #SmartCustody, which can all be found at our Smart Custody Repo. These articles focus on some of the newer technologies, which allow even better #SmartCustody.

New Scenario

A new scenario on multisigs will be the heart of a new book.


Multisigs help ensure the resilience of #SmartCustody by eliminating single points of failure and single points of compromise.

SSKR Shares

Shamir’s Secret Sharing and other sharding schemes attack resilience from a different direction while maintaining your independence. They allow you to backup your cryptography seeds in a safe, distributed manner.


Timelocks are the next generation #SmartCustody solution, creating ways to retrieve digital assets if a seed (or even a principal!) is no longer available.

Also see our experimental mori-cli app for a real usage of Timelocks.

Case Studies

A look at how manufactured hardware devices and released software apps meet #SmartCustody and Gordian ideals.

Future Releases & Mailing List

Keep apprised of our work on #SmartCustody, the next edition of the book, and other releases of best-practices and other educational documents through our email newsletter:

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