Orderbook (Beta)

⚠️ Beta — new features in progress. The Orderbook API is under active development. Endpoints, payload shapes, market identifiers, and semantics may change without notice. Treat it as preview; don't build production-critical flows on it yet.

The Subfrost Orderbook API is a live read + stream surface over the off-chain PSBT order books that settle on Bitcoin via alkanes. It gives you real-time snapshots (REST) and a firehose (WebSocket) of open orders across two sources:

• orbitals — orbital NFT ↔ DIESEL listings and offers (module / collection markets)
• lending — pre-signed loan-offer PSBTs, creditor/debitor (asset-pair markets)

Subfrost is the source of truth for the underlying orders; this API is a low-latency, read-optimized replica, so a delta you receive on the WebSocket is always durably queryable via REST.

Base URL

Every orderbook endpoint lives under your API key:

https://mainnet.subfrost.io/v4/{api_key}/orderbook

Authentication is the same as the rest of the platform — the API key is a path segment (see Authentication). Reads accept any active key; the CDC ingest endpoint requires an admin key.

Market model

Markets are addressed by a single flat topic string:

<source>:<network>:<scope>:<key>

Pair topics are directional — loanId_collateralId — and are not sorted. Colons inside the key (alkane ids like 2:0) are part of the topic; treat the whole topic as an opaque string.

Every order carries the full set of topics it belongs to, so a single subscription (e.g. a pair) receives exactly the orders in that market, and the whole-book topic receives everything.

The order envelope

All orders — orbitals and lending, listings and offers — are normalized into one shape:

{
  "source": "lending",
  "id": "clx…",
  "network": "mainnet",
  "kind": "offer",
  "marketKey": "lending:mainnet:pair:2:0_32:0",
  "topics": ["lending:mainnet:book:*", "lending:mainnet:loan-token:2:0", "lending:mainnet:pair:2:0_32:0"],
  "side": "creditor",
  "makerAddress": "bc1q…",
  "status": "open",
  "price": "1200",
  "priceUnit": "apr-bp",
  "assets": [
    { "role": "loan", "tokenId": "2:0", "amountRaw": "1000000" },
    { "role": "collateral", "tokenId": "32:0", "amountRaw": "5" }
  ],
  "psbt": "cHNidP8B…",
  "createdAt": 1784592000000000,
  "updatedAt": 1784592000000000,
  "ext": { "aprBp": "1200", "durationBlocks": "144" }
}

Next: REST endpoints · WebSocket firehose.