Normativity: Normative (when implemented) Stability: Experimental Status: [PHASE 3 — not yet implemented]
Part of the Colabonate Protocol Specification · ← Back to Protocols
Proximity Proof is the Identity Level 2 verification mechanism. It enables a pubkey to move from Level 1 (self-declared) to Level 2 (peer-attested) without requiring biometric ZK verification (Level 3 / HID). Two independent, previously-verified peers attest — via signed Nostr events — that they met the subject in person.
Level 2 gates participation in medium-value tickets, community mediation panels, and DAO voting in models where 1P1V is unavailable.
A Proximity Proof is a Kind 30026 Nostr event. Two proofs from two different verifier pubkeys, each already at Level 2 or higher, are required to elevate a subject to Level 2.
Minimum required tags (full schema belongs in nostr-events.md § Kind 30026 once this phase ships):
| Tag | Value | Purpose |
|---|---|---|
subject |
subject pubkey (hex) | Who is being attested |
verifier_level |
2 or 3 |
Claimed verifier level at time of signing |
encounter_ts |
Unix timestamp | When the in-person encounter took place |
location_hint |
optional coarse geohash or city | Sybil-pair detection; never precise coordinates |
d |
addressable tag <subject>:<encounter_ts> |
Deduplicates replays |
The subject's identity handler aggregates valid Kind 30026 events; upon observing two from distinct verifiers within a rolling 180-day window, it issues a Kind 30021 (Credential) event elevating the subject to Level 2.
- A single verifier pubkey may issue at most 1 proximity proof per subject per 90 days.
- Two verifier pubkeys that co-attest more than 5 subjects together in 30 days are flagged for DAO review (possible Sybil ring).
- A verifier demoted below Level 2 invalidates their outstanding proximity proofs prospectively (existing Level 2 credentials are not retroactively revoked).
Phase 1 (V1) ships Level 0 (self-declared pubkey) and Level 1 (LNURL-Auth attested). Level 2 requires:
- A stable Level 2+ verifier population (chicken-and-egg — bootstrapped by Foundation DAO members).
- Nostr infrastructure maturity around Kind 30026 relay acceptance and replay protection.
- DAO governance to handle verifier misconduct reports.
None of these are V1 blockers, so the mechanism is specified at the level needed for third-party implementers to plan, but the handler, endpoints, and UI are deferred.
- Identity Protocol — Level 0–3 overview
- Nostr Events § Kind 30026 — event schema (placeholder until this phase ships)
- Nostr Events § Kind 30021 — Credential Event — credential issuance
- DAO Codex — sanction process for misbehaving verifiers
- ADR-010 — Identity Level Model
Part of the Colabonate Protocol Specification · ← Back to Protocols