Gemini WebSockets - Graylayer

Upstream: wss://wsapi.fast.gemini.com

Connect

wscat -c "wss://gateway.graylayer.tech/ws/gemini?api_key=your_key"

After connecting, subscribe to symbols following the Gemini WebSocket API:

{
  "type": "subscribe",
  "subscriptions": [
    {"name": "l2", "symbols": ["BTCUSD", "ETHUSD"]}
  ]
}

Prediction market streams

Subscribe to prediction market symbols to receive real-time updates:

{
  "type": "subscribe",
  "subscriptions": [
    {"name": "l2", "symbols": ["TRUMPWIN"]}
  ]
}

Refer to the Gemini WebSocket docs for the full list of subscription types and event formats.

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