WebSockets

Stream real-time market data without polling. WebSocket connections don't count against your rate limit.

Connection URLs

Exchange	WebSocket URL
Hyperliquid	Public (market data) `wss://api.paperx.co/v1/exchanges/hyperliquid/ws` Private (user data) `wss://api.paperx.co/v1/exchanges/hyperliquid/ws/user?apiKey=YOUR_KEY`
Uniswap	Coming soon

Basic Connection

Python Example

import websocket
import json

def on_message(ws, message):
    data = json.loads(message)
    print(f"Received: {data}")

def on_open(ws):
    # Subscribe to BTC trades
    ws.send(json.dumps({
        "method": "subscribe",
        "subscription": {"type": "trades", "coin": "BTC"}
    }))

ws = websocket.WebSocketApp(
    "wss://api.paperx.co/ws",
    header={"X-API-Key": "pe_your_api_key"},
    on_message=on_message,
    on_open=on_open
)
ws.run_forever()

Public Subscription Types

No authentication required. Perfect for market data dashboards and price alerts.

allMids

All mid prices for every asset (updates ~500ms)

l2Book

Order book depth (requires coin param)

trades

Real-time trades for a coin

candle

OHLCV candles (coin + interval)

activeAssetCtx

Funding, OI, mark/oracle price for a coin

bbo

Best bid/offer stream

Private Subscription Types

Require a valid API key. These channels mirror Hyperliquid 100%.

orderUpdates

Order status changes (open/filled/cancelled)

userFills

Your fills (supports aggregateByTime)

userEvents

All account events (fills, funding, liquidations)

userFunding / userFundings

Funding payments (both singular + plural variants)

webData2 / webData3

Clearinghouse state (legacy + current)

notification

System notifications (margin alerts, billing, etc.)

twapStates

TWAP order status + progress

clearinghouseState

Direct clearinghouse subscription

openOrders

Live snapshot of all open orders

userTwapSliceFills

TWAP slice execution feed

userTwapHistory

Historical TWAP execution summary

userNonFundingLedgerUpdates

Non-funding ledger events

activeAssetData

Per-asset detail (coin + user context)

Best Practices

Implement reconnection logic

WebSocket connections can drop. Always implement automatic reconnection with exponential backoff.

Handle heartbeats

Send periodic pings to keep the connection alive. The server will disconnect idle connections.