Multi-Currency

1. Enable Multiple Chains

So far we've used testnet4. But Bitcoin has multiple networks, and your pod can accept deposits from any of them:

jss start --pay --pay-cost 1 --pay-token PODS --pay-rate 10 \
  --pay-chains "tbtc3,tbtc4"

The --pay-chains flag tells JSS which chains to accept. Each chain has its own mempool API for verification:

2. Deposit on Two Chains

The TXO URI prefix tells the server which chain to verify against:

# Deposit testnet4 sats
curl -X POST http://localhost:4443/pay/.deposit \
  -H "Authorization: Nostr $NIP98_TOKEN" \
  -d "txo:tbtc4:abc123...789:0"

# Deposit testnet3 sats
curl -X POST http://localhost:4443/pay/.deposit \
  -H "Authorization: Nostr $NIP98_TOKEN" \
  -d "txo:tbtc3:def456...012:1"

3. Check Your Balances

curl -H "Authorization: Nostr $NIP98_TOKEN" \
  http://localhost:4443/pay/.balance

{
  "did": "did:nostr:5e7617...45af",
  "balance": 0,
  "cost": 1,
  "unit": "sat",
  "balances": {
    "tbtc3": 285444,
    "tbtc4": 572393
  }
}

Two currencies, one account, one key. Each tracked separately in the webledger.

4. Peer-to-Peer Trading

With multiple currencies, you can trade. The secondary market uses sell orders:

# Alice creates a sell order: 1000 tbtc3 for 500 tbtc4
curl -X POST http://localhost:4443/pay/.sell \
  -H "Authorization: Nostr $ALICE_NIP98" \
  -H "Content-Type: application/json" \
  -d '{"sell": "tbtc3", "amount": 1000, "price": 500, "want": "tbtc4"}'

# Bob fills the order
curl -X POST http://localhost:4443/pay/.swap \
  -H "Authorization: Nostr $BOB_NIP98" \
  -H "Content-Type: application/json" \
  -d '{"orderId": "..."}'

The pod acts as escrow. It holds Alice's tbtc3 until Bob pays the tbtc4. When the swap completes, both balances update atomically. No trust between Alice and Bob — the pod enforces the trade.