Node.js

Node.js SDK

The official Node.js SDK for GEX Engine. Built with TypeScript from the ground up, providing complete type safety, async/await support, and built-in WebSocket streaming. Works in Node.js 18+ and modern edge runtimes.

Installation

npm install @gexengine/sdk

Or with yarn or pnpm:

yarn add @gexengine/sdk
# or
pnpm add @gexengine/sdk

Initialization

import { GEXClient } from "@gexengine/sdk";

const client = new GEXClient({ apiKey: "YOUR_API_KEY" });

// Or use an environment variable (recommended)
// GEX_API_KEY=your_key
const client = new GEXClient(); // reads from GEX_API_KEY

Fetching Data

Gamma Exposure

const gex = await client.gex("SPX");

console.log("Total GEX:", gex.data.total_gex.toLocaleString());
console.log("Net GEX:", gex.data.net_gex.toLocaleString());
console.log("Spot:", gex.meta.spot);

Streaming

const stream = client.stream("SPX", {
  channels: ["gex", "signals", "regime"],
});

stream.on("gex", (data) => {
  console.log("Total GEX:", data.total_gex.toLocaleString());
});

stream.on("regime", (data) => {
  console.log("Regime:", data.regime, "Strength:", data.strength);
});

stream.on("error", (err) => {
  console.error("Stream error:", err.message);
});

// Clean up when done
// stream.close();

Portfolio Analysis

const result = await client.portfolio.analyze({
  positions: [
    { symbol: "SPX", quantity: 10, type: "call", strike: 6000, expiry: "2026-03-21" },
    { symbol: "SPX", quantity: -5, type: "put", strike: 5800, expiry: "2026-03-21" },
  ],
});

console.log("Portfolio GEX:", result.data.total_gex);
console.log("Net Delta:", result.data.net_delta);
console.log("Regime Alignment:", result.data.regime_alignment);

Error Handling

import { GEXClient, GEXError, RateLimitError } from "@gexengine/sdk";

try {
  const gex = await client.gex("SPX");
} catch (err) {
  if (err instanceof RateLimitError) {
    console.log(`Rate limited. Retry after ${err.retryAfter}s`);
  } else if (err instanceof GEXError) {
    console.log(`API error ${err.statusCode}: ${err.detail}`);
  }
}

TypeScript Types

All response types are exported and can be used for type-safe integration:

import type { GEXResponse, RegimeResponse, LevelsResponse } from "@gexengine/sdk";

function handleGex(gex: GEXResponse) {
  // Full autocomplete and type checking
  const totalGex: number = gex.data.total_gex;
  const spot: number = gex.meta.spot;
}