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Alfred Zhang
Alfred Zhang

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Stablecoin Settlement: How We Replace 2-3 Day Card Settlement with Seconds

When you tap your Visa card at a cafe, the money doesn't arrive for 2-3 business days. On weekends and holidays, it's even longer.

Our settlement happens in seconds. Here's how.

How Visa Settlement Works

Visa's settlement process:

  1. Authorization (~2 seconds): Issuer approves the transaction
  2. Clearing (~24-48 hours): Transaction data is batched and reconciled
  3. Settlement (~2-3 business days): Actual funds move between banks via ACH/wire

During this 2-3 day window:

  • The merchant doesn't have the money
  • The consumer's bank has put a hold on the funds
  • Multiple intermediaries are reconciling ledgers
  • Each intermediary takes a fee

How OpenPasskey Settlement Works

  1. Tap (~500ms): Card signs transaction with P-256
  2. Verification (~2 seconds): RIP-7212 precompile verifies signature on Base L2
  3. Settlement (~3 seconds): AUD stablecoin transfers to merchant's CREATE2 receiver

Total time: under 6 seconds.

The ClearingVault

Our settlement happens through a ClearingVault smart contract. When a valid card tap is verified:

  1. The ClearingVault checks the P-256 signature (via RIP-7212)
  2. Verifies the transaction hasn't been replayed (nonce check)
  3. Routes AUD stablecoins to the merchant's dedicated receiver address
  4. The receiver is a CREATE2 address, deterministically generated from the merchant's ID

Each merchant gets their own receiver address. Funds are instantly accessible.

Why Stablecoins?

Regulated AUD stablecoins maintain a 1:1 peg with the Australian dollar, backed by AUD reserves held in regulated Australian institutions.

For the merchant, the experience is: tap happens, AUD appears in their account. The fact that settlement happens on-chain is invisible.

The Cost Comparison

Visa OpenPasskey
Settlement time 2-3 business days ~5 seconds
Interchange fee 0.3-0.8% 0%
Scheme fee ~0.05% 0%
On-chain gas N/A <$0.001
Merchant receives 99.2-99.7% ~100%

For Developers

The ClearingVault is a standard Solidity contract deployed on Base. The key innovation is using RIP-7212 to bridge the gap between EMV card cryptography (P-256) and on-chain settlement.

This pattern (physical device signature → on-chain verification → instant settlement) is applicable beyond payments: access control, ticketing, supply chain, identity.


3,200+ users, 20+ Sydney cafes, settling in seconds. OpenPasskey | @OpenPasskey

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