funman300
397d46f174
The "4-byte header" that precedes every response class name in .rdata, which cost six failed class-to-deserializer resolutions before anyone noticed the offset, is not a length prefix or a refcount. It is the string RS4:. The full literal is RS4:FutXServerResponse, and searching for the bare class name lands four bytes in. Verified directly on three classes: FutDestroyMatchServerResponse name@0x18021d694 header = b'RS4:' FutGetDraftCurrentStateServerResponse name@0x180224204 header = b'RS4:' FutStickerBookStats2ServerResponse name@0x1802220cc header = b'RS4:' Found by a verification agent that had been instructed to distrust the rule. It did, and came back with the reason rather than the offset. A magic constant you have to remember is a rule you will eventually get wrong; a prefix you can read is not. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01VUT92pz6RWKih9dSr8ZpxW
OpenFUT
Offline Ultimate Team — like SPT, but for FIFA 23.
OpenFUT replaces EA's retired FUT servers with a fully offline, single-player backend. You own FIFA 23 legitimately. You just want to keep playing after EA shut down the servers.
Repositories
| Repo | Purpose |
|---|---|
openfut-core |
Game-independent offline FUT backend |
openfut-bridge |
FIFA 23 integration layer + reverse-engineering proxy |
Architecture
FIFA 23 client
│
▼
┌─────────────────┐
│ openfut-bridge │ ← intercepts FUT traffic, maps routes, logs unknown
└────────┬────────┘
│
▼
┌─────────────────┐
│ openfut-core │ ← offline FUT backend: profiles, packs, squads, SBCs
└─────────────────┘
│
▼
SQLite database
Core is game-independent. It speaks a clean REST API and knows nothing about FIFA 23 internals.
Bridge is FIFA-specific. It speaks FIFA 23's wire protocol and translates it into Core API calls. Bridge is where all reverse engineering work happens.
Current Status
| Feature | Status |
|---|---|
| Local profiles + clubs | ✅ Working |
| Coin system | ✅ Working |
| Pack generator | ✅ Working |
| Card collection | ✅ Working |
| Squad builder | ✅ Working |
| Objectives engine | ✅ Working |
| SBC engine | ✅ Working |
| Match rewards | ✅ Working |
| NPC transfer market | ✅ Working |
| Statistics | ✅ Working |
| FIFA 23 integration | 🔴 Reverse engineering in progress |
| Chemistry calculation | 🟡 In progress |
| Full Draft mode | 🟡 In progress |
| Squad Battles AI generator | 🟡 In progress |
| Objectives claim flow | 🟡 In progress |
Running
# Start the offline backend
cd openfut-core
cargo run
# Start the proxy (for traffic capture / FIFA integration)
cd openfut-bridge
cargo run
Core listens on http://127.0.0.1:8080 by default.
Bridge listens on http://127.0.0.1:8443 by default.
Design Principles
- Offline-first. No EA account required. No internet connection needed.
- Single-player only. This is not a multiplayer server emulator.
- Data-driven. All cards, packs, SBCs, and objectives are JSON files. Everything is moddable.
- Clean architecture. Core has zero knowledge of FIFA 23. Bridge has zero game logic.
- No copyrighted assets. No real player images, no EA trademarks in data files.
Disclaimer
This project is not affiliated with EA Sports. You must own FIFA 23 legitimately to use this software. This project does not bypass any ownership verification and is intended only to restore offline playability of a game whose online services have been retired.