Building block
Identity
One identity per person, split across their own devices. No login screen, no password database.
An identity is a self-certifying cryptographic key, a DID, created on a device rather than issued by a server. The master key is never held whole: it is split across a person's own devices using the FROST threshold signature scheme from the moment it exists, and re-split whenever a device is added or removed. Recovery runs on a backed-up recovery phrase, and a deliberate key rotation is recorded as a real event in the identity's history.
What a person notices
There is no sign-up form. The identity is created once, on a device the person already owns, and it just works from there. Unlocking uses biometrics by default, with a password the person does need to remember.
Adding a laptop or a second phone to the same identity does not feel like creating a new account. It feels like adding a device to something that was already theirs.
If every device is lost, the identity is not automatically gone. A person who wrote down their recovery phrase beforehand can get back in, and the system can tell them plainly whether they actually saved one.
A person can deliberately replace their own key, for example after a scare or a clean start, and that change becomes part of the identity's own history rather than a quiet swap nobody can see.
What you get as a developer
An identity is a self-certifying cryptographic key, a DID, rather than a record some server issues and hands back to you on request. Nothing central has to be up for the identity to be real.
The key is never whole
From the moment an identity exists, its master key is split across the person's own devices using a threshold scheme (FROST). No single device ever holds the complete secret, including the very first one.
Growing the identity re-splits it
When a device is added, the key is re-shared across every current device. The key is never reassembled on one machine to do this, and it stays split across the whole set afterward.
Recovery is honest about its own state
If someone loses all their devices, the only way back in is a recovery phrase they backed up in advance. The identity keeps track of whether that backup actually happened, instead of assuming it did.
Rotation is a real event
A person can rotate their master key on purpose. That rotation is recorded in the identity's own history as something that happened, not hidden as an implementation detail.
Local-first: there is no server holding the identity or deciding whether it is valid. Any device that is part of the identity can verify it on its own.
How it connects
Devices
The identity's key lives split across a person's devices. Adding or removing a device is what triggers the re-split described above.
Contacts & friendships
Every pseudonym a contact sees is derived from this identity. Nobody meets the raw identity directly in a relationship; they meet a pseudonym computed from it.
Trust graph
The identity is the node other people's trust attaches to. Everything the trust graph tracks about a person points back to this one key.
Vault
Recovery material, including the phrase that can rebuild a lost identity, lives in the vault rather than inside the identity record itself.