The time capsule
A secret that only opens from a chosen date on, for a will, a handover.
How it works, in plain words
- 1. The capsule wraps your shares
- 2. At the date, drand publishes the beacon
- 3. Shares + beacon = secret reconstructed
Kintaya never takes part in this chain.
The capsule wraps your shares in a time lock. At the chosen date, a public beacon (drand) publishes the value that unlocks it; gathering enough shares plus this beacon is enough to reconstruct.
What it depends on
The capsule opens even if we disappear.
A public randomness network, run by a coalition of around twenty independent organizations: Cloudflare, EPFL, the University of Chile, and others.
The limits, in plain words
Opening assumes the drand network still publishes its beacons at your chosen date. Over years, that is solid; over several decades it becomes a bet on the network's longevity, worth keeping in mind for very long horizons.
Two theoretical routes, both practically out of reach: a secret collusion of a majority of drand's independent organizations; or a quantum computer able to force the lock - a machine that does not exist in 2026, within reach of only a handful of the most powerful states or laboratories, after programs costing billions. Even then, only the opening date would be brought forward; the secret stays protected by the quorum, Shamir and AES-256, resistant to quantum computers.
The offline path
Once the beacon is published at the date, it is public and permanent: you can fetch it through any channel and open the capsule entirely offline.
What is visible
Almost nothing, and never the secret. If you fetch the beacon online when opening, someone intercepting your connection at that exact moment could infer the opening date (the round number), a minor piece of metadata - never the secret, never the people involved. Via the offline path, even that stays invisible.
When to use it
For a handover at a known date: a digital will, a message to open later, a secret entrusted for a specific day.
Going further
The full technical treatment. .