# Murmelbahn: decoding GraviTrax course files

> Murmelbahn decodes GraviTrax course data obtained through the Ravensburger app API and presents course details and bills of materials in a web app. The author used ImHex to work out changing file formats and includes a schema and parser for recent course versions.

- Type: Case study
- Targets: App
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-08
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/lfrancke/murmelbahn>
- Primary source: <https://github.com/lfrancke/murmelbahn/blob/8d7974a5d67b1387032fd475b9a8de6b8a567544/README.md>
- Catalog page: <https://awesomerea.org/resources/murmelbahn-case/>
- Record JSON: <https://awesomerea.org/resources/murmelbahn-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/murmelbahn-case/index.md)

## Requirements & limits

- **Prerequisites:** The documented build uses Rust, a frontend npm build, and a PostgreSQL DATABASE_URL.
- **Limits:** Course parsing covers the latest three format generations, dating from after 2020.
- **License:** Apache-2.0.

## Primary sources

1. <https://github.com/lfrancke/murmelbahn/blob/8d7974a5d67b1387032fd475b9a8de6b8a567544/README.md>
2. <https://github.com/lfrancke/murmelbahn/blob/8d7974a5d67b1387032fd475b9a8de6b8a567544/CHANGELOG.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.