Open‑source documentation and tooling for Star Stable Online’s proprietary file formats.
Fast. Minimal. Developer‑friendly.
PS: This project is developed in my free time — usually when I’m bored enough to open Ghidra and reverse‑engineer Star Stable Online’s internal logic, or when I need more tool coverage for my own private modding utilities for the game.
If something breaks, please open an issue… or even better, submit a PR!
SSO Formats Core is an open‑source initiative to fully document, parse, and manipulate the proprietary file formats used by Star Stable Online and the underlying PXEngine.
The goals are simple:
- Make these formats easy to understand
- Provide clean, well‑documented reference implementations
- Keep everything fast enough for real‑time tooling
- Ensure the project remains fully open‑source and accessible
Whether you're building modding tools, research utilities, or simply exploring how the game stores its data, this project aims to be the definitive reference.
- UTF‑8 keys
- UTF‑16LE values
- Caesar‑style obfuscation
- Full specification included
- C and Python reference implementations
- CRC32 validation
- File size + path metadata
- Used by PXEngine to verify shipped assets
- Fully documented structure
More formats will be added as they are researched and verified.
- Clean C API for maximum performance
- Python bindings for rapid tooling
- Zero external dependencies
- Little‑endian optimized (matching PXEngine’s design)
- Memory‑safe wrappers for easy integration
- Readable specifications for each file type
- Fast parsing (targeting ~100ns to ~300ns per entry in C depending on hardware)
Each file format includes:
- A full technical specification
- Struct layouts
- Parsing flow
- Notes on unknown or reserved fields
- Reference code for reading/writing
- Examples and test files (when available)
All documentation lives in the docs/ directory.