Introduction

The physics layer beneath markets

What is GEX Engine

GEX Engine is an options intelligence and market-structure analytics API that computes dealer-positioning estimates, gamma exposure, and market microstructure signals. It provides a research layer for studying the mechanical hedging pressure that can influence equity index market structure.

When market makers sell options to customers, they inherit greek exposures that must be hedged dynamically. The aggregate positioning of these dealers can create observable flow patterns. GEX Engine quantifies this positioning for research, simulation, forecasting, and risk-aware decision support.

Why Dealer Positioning Matters

Dealers collectively hold trillions of dollars in options inventory. Their hedging activity is not speculative -- it is mechanical. When dealers are long gamma, they buy dips and sell rallies, compressing volatility. When they are short gamma, they are forced to sell into falling markets and buy into rising markets, amplifying moves. This is not a theory. It is the plumbing of the market.

GEX Engine translates this structure into decision-support signals for research workflows. Warm-cache computations are designed for low latency, and approved API access can stream results via REST or WebSocket.

Key Capabilities

Five Exposure Types

GEX -- Gamma Exposure per strike. The core metric that determines whether dealers suppress or amplify moves. VEX -- Vanna Exposure. Sensitivity of dealer delta to implied volatility changes. CEX -- Charm Exposure. Time decay of dealer delta, driving predictable end-of-day flows. DEX -- Delta Exposure. Raw directional positioning across strikes. VOX -- Volga Exposure. Second-order volatility sensitivity for tail risk detection.

Regime Detection

Automatic classification of the current gamma environment into positive_gamma, negative_gamma, or neutral regimes. Includes regime strength scoring, CDEX, and amplification factor.

Shadow Gamma

Detection of hidden exposure from exotic options, barrier structures, and structured products that do not appear in standard open interest data. The Gamma Adjustment Factor (GAF) quantifies the magnitude of this hidden positioning.

Hedging Bands

Identification of dormant gamma zones where concentrated dealer positioning activates during price moves. These bands act as dynamic support and resistance levels driven by mechanical hedging flows.

VPIN and Flow Forecast

Volume-Synchronized Probability of Informed Trading (VPIN) for toxicity detection, combined with multi-channel flow forecasting that incorporates gamma, vanna, charm, and shadow gamma components.

Architecture

The engine is built as a 9-layer computation pipeline. Options data flows through dealer positioning models (3 generations of increasing sophistication), greek computation via BSM and SVI volatility surfaces, five exposure aggregation paths, and finally into signal generation. The pipeline is optimized for low-latency warm-cache computation.

Results are available via 29 REST endpoints, 2 WebSocket streams, and a portfolio analysis suite. All endpoints return JSON.

Supported Symbols

GEX Engine supports the major US equity index options: SPX, SPY, QQQ, IWM, NDX, and RUT. These are the most liquid options markets with the densest dealer positioning, making them ideal for gamma exposure analysis.