Pubky Invites: A Reputation-Gated Onboarding Flow for New Users

Following up with the Synonym Marketing Hackathon, we have Pubky Invites, one of the most interesting projects, created by Mathew, James, and Tomos. It’s a new onboarding route that lets existing Pubky users mint shareable invite codes from inside the app, gated on their own activity instead of sats or SMS. The flow works end-to-end on staging and is waiting on a final spam-resistance call before it ships into the main app.

Core Idea: Distribution Through Trust

Joining Pubky.app has historically required one of three things: a small Lightning payment, a phone number for SMS verification, or asking someone for an invitation code. All of them work. None of them are particularly friction-free, but Pubky does give 1GB free storage, so some control is needed.

Pubky Invites adds a fourth route. Existing users with enough activity can mint invite codes from inside the Pubky app and pass them to friends, so new users arrive through someone they already trust.

How Pubky Invites Works

The flow lives inside the Pubky app:

• User clicks the Request an invite button
• The backend checks eligibility based on the user’s activity (post cadence, interactions, trust signals from the indexer)
• If eligible, an invite code is minted and presented as a QR, a copy-able link, or an OS share-sheet action
• The recipient scans or clicks the code and lands directly in onboarding and profile creation, with no code to type in

Underneath the eligibility check, the project uses a novel proof of session pattern. The Pubky app writes a secret to the user’s Homeserver, then includes the same secret in the request to Homegate. Homegate verifies the request by reading the Homeserver, since only the legitimate user could have written that value. No extra signing keys, no extra trust layer.

The hackathon demo uses a simple placeholder eligibility rule (post count above a threshold). The production version could use harder-to-fake signals such as social-graph reputation and interactions with already-trusted users.

What Changes With Invites

Pubky Invites turns existing users into the primary distribution channel for new ones. Every network that has grown organically has had this moment: existing members start vouching for new arrivals, and the marginal cost of acquisition drops to near zero.

The mechanic also tilts the network toward trusted growth. A new user arrives connected to someone with a real history on Pubky, rather than out of the cold, which makes the early experience less empty and the moderation surface easier to manage.

All projects in this series were built during a two-day marketing hackathon. They are experimental, and may or may not become actual products.

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