# OpenSpy Core: reconstructing GameSpy online services

> OpenSpy Core reconstructs GameSpy online services as separate processes communicating through HTTP, AMQP, and Redis. Its QR service handles ASCII V1 and binary V2 formats, while server browsing supports legacy and enctypex variants. Other implemented services cover NAT negotiation, presence, account search, game statistics, chat, and selected EA FESL traffic.

- Type: Case study
- Targets: Protocol
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-06
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/openspy/openspy-core>
- Primary source: <https://github.com/openspy/openspy-core/blob/221c6a7931914362a04ffe6f374957eff2fe1bac/README.md>
- Catalog page: <https://awesomerea.org/resources/openspy-core-case/>
- Record JSON: <https://awesomerea.org/resources/openspy-core-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/openspy-core-case/index.md)

## Requirements & limits

- **Prerequisites:** Running requires Redis and RabbitMQ; openspy-web-backend is recommended for the full setup.
- **Prerequisites:** Building on Debian-based systems requires the listed native libraries and CMake.
- **Limits:** Server browsing does not support enctype 1, map loop, or player search; FESL currently supports BF2142.
- **License:** No licence file in the repository.

## Primary sources

1. <https://github.com/openspy/openspy-core/blob/221c6a7931914362a04ffe6f374957eff2fe1bac/README.md>
2. <https://github.com/openspy/openspy-core/blob/221c6a7931914362a04ffe6f374957eff2fe1bac/DESIGN.md>

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## About this entry

The description was reviewed against primary sources.
Original editorial content: MIT. Linked projects, papers and assets retain their own rights and licenses.