deLinZK
ETHFORALL · 2023CREDENTIAL · private
employer: Covalent
tenure: 2y 4m
ZK CIRCUIT
VERIFIED · public
employed: …
employer: █████
Anyone can claim a job title with no way to verify it — and background checks are slow, invasive, and still offer no cryptographic guarantee.
deLinZK replaces trust-me credentials with mathematically unforgeable ones. Using Polygon ID and the Iden3 framework, a verified organization issues a Verifiable Credential encoding an employee's tenure. When the employee applies on the integrated job board, they generate a zero-knowledge proof of employment — revealing no underlying personal data. Built at ETHForAll Online VIII.
After admin verification, an org issues a Verifiable Credential to an employee's identity wallet. On the job board, the employee generates a zero-knowledge proof that proves employment without revealing data. Redis manages real-time state across the WebSocket and REST layers; ZK proofs replace JWTs entirely.
VET
admin confirms the org is legitimate
Next.js
ISSUE
credential of tenure to the identity wallet
Polygon ID · Iden3
PROVE
zk proof of employment on the job board
zero-knowledge
VERIFY
checked, no personal data revealed
Redis · Supabase
Polygon ID imposes a 15-digit integer limit on credential attributes — encoding employment tenure into one field was a real puzzle. I solved it with SHAKE-128 hashing, converting to hex then decimal radix to produce compact, uniquely deterministic 48-bit values:
15-digit constraint
the hard limit on credential attributes
SHAKE-128 encoding
hash → hex → decimal radix → 48-bit values that fit
zk-only auth
JWTs replaced entirely by proofs; email is for comms only
org verification
issuers vetted before they can vouch