Crypto Fiat Bridge

crypto-fiat-bridge

Overview

Automated crypto-to-fiat payment pipeline for converting APT holdings to OpenRouter API credits via the PYUSD stablecoin bridge. All operations require explicit approval.

Architecture

APT (Aptos) --[Liquidswap DEX]--> PYUSD0 (Aptos) --[Wormhole Bridge]--> PYUSD (Ethereum) --[Coinbase Commerce]--> OpenRouter

Workflow Steps

1. Check APT Balance

THRESHOLD = 0.5 APT (minimum for gas + fees)

aptos_balance() -> current_apt
IF current_apt < THRESHOLD:
  ABORT "Insufficient APT balance"

2. Execute APT -> PYUSD0 Swap

aptos_swap(
  fromCoin: "APT",
  toCoin: "PYUSD0",
  amount: swap_amount,
  dex: "liquidswap",
  slippage: 0.5
)
-> Returns decision_id for approval

3. Bridge PYUSD0 -> PYUSD

Wormhole bridge transaction:
- Source: Aptos PYUSD0
- Destination: Ethereum PYUSD
- Finality: ~15 minutes

4. Pay OpenRouter via Coinbase Commerce

swapAndTransferUniswapV3Token(
  recipient: OPENROUTER_MERCHANT_ADDRESS,
  token: PYUSD_ADDRESS,
  amount: payment_amount,
  poolFee: 3000
)

MCP Tools Used

• aptos_balance - Check APT/PYUSD0 holdings
• aptos_swap - Execute APT -> PYUSD0 via Liquidswap
• aptos_transfer - Send tokens to bridge address
• aptos_approve - Confirm pending transactions

Security

Approval Requirements

• All transactions use confirmation_mode approval
• No automatic execution of value transfers
• Each step requires explicit aptos_approve(decision_id, approve: true)

Key Management

# Keys accessed ONLY via fnox/age encryption
fnox get aptos-private-key | age -d -i ~/.age/key.txt

NEVER store raw private keys in environment variables, config files, skill definitions, or database tables.

Verification Queries

-- Validate pending transactions
SELECT tx_hash, amount, timestamp
FROM crypto_bridge_transactions
WHERE status = 'pending'
ORDER BY timestamp DESC;

Ledger location: /Users/alice/worldnet/ledger.duckdb