Archival Journal for Cryptographic Truth · A.D. MMXXVI

Seal a credential.
Prove one fact.
Reveal nothing else.

Zelyo mints credentials as sealed attestations on a scholarly ledger — then lets a holder prove a single fact in zero knowledge. The chain records only an anonymous seal. The rest stays private.

Network
Stellar · Soroban
Proof System
Noir · UltraHonk
Status
Sealed & Live
Proven ✓

Identity Folio No. 73

Data Engineering Certificate

Track
Data Engineering
Issuer
Institute of Distributed Systems
Issued
2026-07-14
Signature
0x244af422…

Status: Active

Sealed 7/14/2026 · revealed track

Prove
Fig. 1 — A sealed credential folio: one fact revealed, everything else private. Plate I · wallet
§ I · The Three Reveals

What the chain sees, and what it never does.

Three properties that make a credential worth sealing — each verifiable on-chain, without exposing the person behind it.

01
visibility_off

Nothing personal on-chain

The ledger records only a nullifier and a bound address — no name, no grade, no course. The proof is the receipt; the data never leaves the holder.

Reveal · On-chain
02
fingerprint

One credential, one registration

A nullifier ties a single proof to a single identity. Reusing it across Sybil attempts is rejected — one seal, one claim, no duplicates.

Reveal · Anti-Sybil
03
verified_user

Selective disclosure

Prove you satisfy a predicate — “track matches,” “grade in range,” “issued before date” — while every other attribute stays strictly private.

Reveal · By request
§ II · The Distillation

From private attributes to a sealed proof.

Credentials enter as leaves in a Merkle tree; the issuer publishes a single root. A holder distills one fact into a proof, sealed and recorded — and the original data is never transmitted.

Fig 1.1 · Distillation
Data
attributes
Hash fn
poseidon2
Proof / Root
sealed ✓

Fig 1.1 — Private attributes converge through a hash function into one sealed, verifiable root.

Zelyo · Prove Console
§ III · Correspondence

Write to the registry.

Questions, integrations, or institutional inquiries — address your correspondence to the keeper of the ledger.

mail

Send us a sealed letter

We answer inquiries about the protocol, issuance, and verification. Expect a considered reply — not an autoresponder.

extension

Carry the seal in your browser

Prove and hold credentials directly from the Zelyo app, or install the Chrome extension to seal and verify on the open web.