qID

qID is an open-source identity and sign-in system built on post-quantum cryptography. A user's qID keys are the same post-quantum signature keys used on the BTX blockchain, a property the project describes as "byte-exact to the chain." qID ships inside the bonuz wallet and PQ Wallet applications and is documented at qid.dev.

#Design

Most sign-in systems rest on passwords or on classical public-key cryptography such as RSA and ECDSA, schemes that a sufficiently large quantum computer running Shor's algorithm could break. qID instead anchors identity in post-quantum signature keys of the kinds standardized by NIST and required by BTX consensus, ML-DSA and SLH-DSA. Authenticating to a service means producing a signature over a challenge that the service verifies against the user's qID public key; no shared secret is stored by the service.

The defining design choice is that identity keys are byte-exact to the chain: the key material that identifies a user is the same kind of key material, in the same encoding, that signs BTX transactions. This removes the need to bootstrap a separate identity infrastructure. A wallet that can sign a BTX transaction can also prove an identity, and verification logic can be shared with node and explorer software rather than reimplemented.

#Distribution and openness

qID is open source. It is not a standalone application; it ships inside wallets, specifically bonuz wallet on iOS and Android and PQ Wallet on desktop. The wallet holds the keys and performs signing, and services verify the resulting signatures. Because the verification side is open, integrating services do not depend on a proprietary component to check sign-ins.

#Relation to qID Connect

qID Connect is a connection layer, in development as of July 2026, that carries sign-in and approval requests between BTX applications and wallets. The division of labor is that qID defines the identity and its signatures, while qID Connect defines how an application reaches the user's wallet to request them.

#Limitations

As with any key-based identity system, control of the key is control of the identity. Key loss and key theft are therefore the primary user-facing risks, and they sit with the wallet that stores the key rather than with the qID protocol itself. Post-quantum signatures are also larger than the classical signatures used in most existing sign-in flows, which increases the size of authentication messages.