Market Data

Real-time crypto prices — REST + a streaming WebSocket.

Rach Market Data gives you the top 250 coins by market cap and live USD prices, served from Rach’s edge cache (no external quota is burned per request). Use the REST API for snapshots and the WebSocket for real-time ticks.

Market Data lives at a different base path than the other Payments services: https://api.rach.finance/v1/market/ (note: no /api/v1). It uses your Payments X-API-Key; only the health check is public.

REST

List coins

curl "https://api.rach.finance/v1/market/coins?page=1&limit=50" \
  -H "X-API-Key: $RACH_KEY"

Response

{
  "as_of": 1751584800,
  "total": 250,
  "page": 1,
  "limit": 50,
  "coins": [
    { "symbol": "BTC", "name": "Bitcoin", "price": "62409.00", "rank": "1", "pct_24h": "2.15" }
  ]
}

Batch prices

Up to 100 symbols in one call:

curl "https://api.rach.finance/v1/market/prices?symbols=btc,eth,sol,usdc" \
  -H "X-API-Key: $RACH_KEY"

Response

{ "prices": { "btc": 62409.00, "eth": 1756.68, "sol": 148.32, "usdc": 1.00 } }

Fetch a single coin / asset

Two ways, depending on how much you need — pass the lowercase symbol as the path parameter.

Just the value — lightweight, for tickers and totals:

cURL

curl "https://api.rach.finance/v1/market/prices/eth" \
  -H "X-API-Key: $RACH_KEY"

Response

{ "symbol": "eth", "price": 1756.68 }

Full detail — price plus rank, 24h change, name and freshness:

curl "https://api.rach.finance/v1/market/coins/btc" -H "X-API-Key: $RACH_KEY"

Response

{
  "coin_id": "bitcoin",
  "symbol": "BTC",
  "name": "Bitcoin",
  "price": "62409.00",
  "rank": "1",
  "pct_24h": "2.15",
  "last_updated": "2026-07-04T01:00:00.000Z"
}

GET /v1/market/prices/{symbol} returns the price as a number; GET /v1/market/coins/{symbol} returns every field as strings. A 404 means the symbol isn’t tracked.

Health (public)

curl "https://api.rach.finance/v1/market/health"
# { "status": "ok", "fresh": true }   — 503 with "fresh": false if the cache is stale

The full REST schemas are in the Payments API reference under Market Data.

WebSocket

Connect for real-time price ticks. Browser WebSocket clients can’t set headers, so the API key is passed in the query string:

wss://api.rach.finance/v1/market/ws?key=<api-key>

Messages

Client → server

{ "op": "subscribe", "symbols": ["btc", "eth"] }
{ "op": "subscribe", "symbols": ["*"] }
{ "op": "ping" }

Server → client

{ "op": "snapshot", "as_of": 1751584800, "coins": [ /* CoinMarket objects */ ] }
{ "op": "tick", "as_of": 1751585100, "changes": [
    { "symbol": "btc", "price": 62800.00, "pct_24h": 2.5, "direction": "raise" },
    { "symbol": "eth", "price": 1740.00, "pct_24h": -0.8, "direction": "fall" }
]}
{ "op": "pong" }

On connect you receive a snapshot of your subscribed symbols, then tick messages as prices change (direction is raise or fall). Send { "op": "ping" } to keep the connection alive; the server replies pong.

Example

Browser / Node (ws)

const ws = new WebSocket("wss://api.rach.finance/v1/market/ws?key=" + RACH_KEY);

ws.onopen = () => {
  ws.send(JSON.stringify({ op: "subscribe", symbols: ["btc", "eth"] }));
};

ws.onmessage = (e) => {
  const msg = JSON.parse(e.data);
  if (msg.op === "snapshot") console.log("snapshot", msg.coins);
  if (msg.op === "tick") for (const c of msg.changes) console.log(c.symbol, c.price, c.direction);
};

// keep-alive
setInterval(() => ws.send(JSON.stringify({ op: "ping" })), 30000);

Limits

10 concurrent WebSocket connections per merchant. Slow consumers have individual ticks dropped (they are not disconnected), so always render the latest tick and don’t assume you receive every one.