Clypr

Built with a team for the WCHL Hackathon, where it placed 3rd nationally. dApps have no good way to reach their users: they either ask for an email or phone number, which leaks identity, or build separate integrations for email, Telegram, Discord and the rest.

With Clypr, a user claims a @handle, signs in with Internet Identity — no passwords — and links the channels they want to be reached on, such as email, Telegram or webhooks. Their own rules decide what gets through: allow, block or route, filtered by sender dApp, conditions and priority.

Any dApp calls one public endpoint, notifyAlias("@handle", …). The rule engine runs on-chain and stores a receipt, then an off-chain bridge delivers the message to the real channel. Users never give their contact details to the app, and developers integrate a single API.