Protocol
Architecture
A note-based shielded pool on Robinhood Chain, with routing, disclosure and settlement modules around it. What each part does and what it can see.
Status: pre-launch. Noirpay is being built. This page describes the design as specified in the whitepaper; nothing on it is live on Robinhood Chain yet, and details can change before launch. See What's live today.
Overview
Noirpay is a note-based shielded pool (a UTXO-style ledger of encrypted notes, in the tradition of Zcash-style designs) deployed as smart contracts on Robinhood Chain, with modules around it for yield routing, card settlement, payroll batching and controlled disclosure. Zero-knowledge proofs let the contracts verify that a transaction is valid (the notes exist, haven't been spent, and balance) without learning what it contains.
Components
| Component | Role | Sees |
|---|---|---|
| Shielded pool | Holds USDG and stock tokens; records note commitments and nullifiers; verifies proofs | Commitments, nullifiers, proof validity; not amounts, owners or assets |
| Edge screener | Gates shield and unshield on sanctions and risk checks; publishes association sets | Deposit and withdrawal addresses |
| Yield router | Allocates pool capital to Robinhood Chain venues; credits returns pro-rata | Pool-level allocation only |
| Settlement module | Settles card programme batches from the pool | Batch totals |
| Batcher | Builds one-transaction payroll batches | Nothing; runs in the client |
| Disclosure | Viewing keys and attestations, verified against public state | Proof validity |
| Relayer + paymaster | Submits proofs so users don't hold ETH; pays gas | That a proof was submitted |
| Client | Key management, note decryption, proof generation, dashboard, exports | Everything, locally |
A transaction, end to end
- The client selects notes to spend, builds new notes for recipients (and change), and generates a proof that inputs equal outputs, inputs are unspent and owned by the signer.
- The relayer submits the proof. The pool checks it, records the new note commitments, and records the spent notes' nullifiers so they can't be spent again.
- Recipients scan for notes encrypted to their key and add them to their balance.
Where privacy comes from
- Commitments hide note contents; nullifiers prevent double-spends without revealing which note was spent.
- Stealth addresses unlink payments to the same handle.
- Pool-level yield and settlement mean the chain sees the pool act, not the account.
- Time decorrelation and consolidation break timing and amount links between entry and exit.
Where compliance comes from
- Edge screening at shield and unshield.
- Association sets published so withdrawals can prove hygiene.
- Viewing keys and attestations issued by the account holder only.
See Security model for what this does and doesn't protect against.