Summary: Nunchuk is a Bitcoin-only multisig custody stack built around collaborative recovery and inheritance. The inheritance-key and timelock design are the point. The rest is support, advisor coordination, and policy packaging around that core.
What it does:
Provides multisignature Bitcoin wallets for individuals, families, groups, and advisors, with onboarding aimed at making complex multisig setups usable on mobile and desktop
Centers inheritance planning as a core wallet design choice by introducing a dedicated inheritance key and timelock-based activation for heirs or trustees
Supports autonomous on-chain inheritance plans where wallet rules change after the timelock expires and the beneficiary can claim funds without Nunchuk’s continued involvement
Offers collaborative-custody and advisor-facing flows through products like Byzantine, where clients retain control while an advisor holds a backup key
Includes operational safety features such as cloud-backed wallet configuration, assisted recovery, emergency lock-down, personal-full-node pairing, spending limits, and configurable co-signing delays for the platform key
Maintains a public developer and automation surface through its GitHub org, CLI, platform-policy tooling, and agent-skills repo for AI-agent integrations
Key claims:
The homepage frames Nunchuk as “the first Bitcoin inheritance solution designed to outlive the company that created it,” emphasizing non-custodial, zero-KYC inheritance design
The platform page says Nunchuk was built to make multisig easier and to create “an easy way for Bitcoiners to pass on their wealth,” with inheritance treated as an essential element rather than an afterthought
The inheritance page explicitly says “We can’t move your bitcoin” and explains that after the timelock expires the wallet rules change on-chain, removing the platform key and empowering the beneficiary or trustee
The platform materials reveal a layered operational model: platform-key spending limits, co-signing delays, assisted recovery, encrypted messaging, and personal-node support
The GitHub org and CLI show that Nunchuk is not only an end-user wallet app; it also exposes wallet-management, miniscript, policy, and automation tooling, including agent-facing skills
Whitepaper: No canonical standalone Nunchuk whitepaper or litepaper surfaced in this pass. The strongest current sources of truth are the official site, platform and inheritance pages, FAQ/support surface, sitemap-discoverable product pages, and the public GitHub organization plus CLI repo; see ../whitepapers/nunchuk-primary-sources-2026-04-28.md.
Read Nunchuk as the inheritance-heavy collaborative-custody branch: more service-mediated than Revault, more explicit about long-lived family and advisor recovery than ordinary multisig wallet notes.