Market data (/perps) - Murmo API

The /perps namespace streams live market snapshots for perpetual markets. You subscribe per symbol and receive market_tick pushes, throttled to at most ~4 per second per symbol.

Event	Direction	Payload	Returns
`subscribe_market`	client → server	`{ symbol: "BTC" }`	`{ ok: true }`
`unsubscribe_market`	client → server	`{ symbol: "BTC" }`	`{ ok: true }`
`market_tick`	server → client	`PerpMarketSnapshot`	—
`connected`	server → client	`{ userId }`	—
`error`	server → client	`{ message }`	—

Example

import { io } from "socket.io-client";

const socket = io("wss://api.alpha-labs.trade/perps", {
  transports: ["websocket"],
  auth: { token: process.env.MURMO_API_KEY },
});

socket.on("connected", () => {
  socket.emit("subscribe_market", { symbol: "BTC" });
  socket.emit("subscribe_market", { symbol: "SOL" });
});

socket.on("market_tick", (snap) => {
  console.log(snap.symbol, snap.markPriceUsd, snap.fundingRatePercentage);
});

// later
socket.emit("unsubscribe_market", { symbol: "SOL" });

`market_tick` payload

{
  "symbol": "BTC",
  "markPriceUsd": 68250.5,
  "midPriceUsd": 68249.0,
  "oraclePriceUsd": 68251.2,
  "fundingRatePercentage": 0.0042,
  "openInterestBaseLots": 1820345,
  "volume24hUsd": 91234567.8,
  "prevDayPriceUsd": 67010.0,
  "receivedAt": "2026-06-02T19:00:00.000Z"
}

Field	Type	Notes
`symbol`	string	Market symbol.
`markPriceUsd`	number	Mark price (USD).
`midPriceUsd`	number \| null	Mid price (USD).
`oraclePriceUsd`	number	Oracle price (USD).
`fundingRatePercentage`	number	Funding rate per funding interval.
`openInterestBaseLots`	number	Open interest in base lots.
`volume24hUsd`	number	24h notional volume (USD).
`prevDayPriceUsd`	number	Price 24h ago (for % change).
`receivedAt`	string (date-time)	When the snapshot was captured.

Unlike the REST API, the market_tick stream sends numeric price/funding/volume fields, not decimal strings — it’s optimized for low-latency streaming. For values you’ll do exact money math on (entry sizing, accounting), read prices from GET /api/v1/perps/markets, which returns the full-precision decimal-string contract.

Subscriptions are per symbol. Subscribe only to the markets you’re tracking to minimize traffic; ticks are already throttled to ~4/sec/symbol.