Documentation

Keys & recovery

Subter is self-sovereign: your identity is controlled by keys only you hold. That is its strength — no company can impersonate, freeze, or read you — and it puts recovery squarely in your hands.

Read this first

Subter cannot recover your keys — there is no password reset for them. If you lose your key material with no backup, that identity is gone for good. Back it up before you rely on it.

What your keys are

Two keys, one identity

An encryption key (for messages) and a signing key (for your identity). Your fingerprint — the id others use — is derived from them.

They live on your device

Generated and stored by the app, in your device’s secure storage. Subter only ever receives public keys and signatures — never a private key.

Enrollment proves control

You bind your keys to your fingerprint by proving you hold them (opening and signing a challenge) — not by uploading anything secret.

Back up your keys

The app can export your key material to a backup file. Treat it like the master key to your identity:

Store it somewhere you control and won’t lose — ideally more than one place (a password manager, an encrypted drive).
Keep it secret. Anyone with your backup can act as you. Never paste it into a website or send it to anyone — including Subter. No Subter page ever asks for a private key.
Back up before you publish anything you care about, and again if the app tells you your keys changed.

Restoring on a new device

Import your backup into the app on the new device. Because it holds the same keys, re-enrolling is a no-op that restores the same identity — same fingerprint, same handle, same published document. Nothing is reassigned and nothing breaks.

If a key is compromised

Key rotation— moving your identity to a fresh signing key while keeping the same fingerprint and history — is on the way. Every identity already carries the commitment that makes rotation possible, so today’s identities will be able to rotate when it ships. Until then, the best protection is a safe backup and a secure device.