# geoWrite 2.1: source that rebuilds the original binaries

> Reverse-engineered cc65 source for geoWrite 2.1, the GEOS word processor, in English and German. The README says a standard compile generates binaries identical to the English and German geoWrite 2.1 distribution binaries. The orig tree holds the collected original versions.

- Type: Case study
- Targets: Binary
- Category: Independent reconstruction cases
- Relationship: Independent reconstruction project
- Sources reviewed: 2026-11-04
- Added to the catalog: 2026-11-09
- Original resource: <https://github.com/mist64/geowrite>
- Primary source: <https://github.com/mist64/geowrite/blob/640f1aba3a68c096c56fafc81b55772db391de35/README.md>
- Catalog page: <https://awesomerea.org/resources/geowrite-21-case/>
- Record JSON: <https://awesomerea.org/resources/geowrite-21-case/record.json>
- Chinese version: [简体中文](https://awesomerea.org/zh/resources/geowrite-21-case/index.md)

## Requirements & limits

- Requires make, cc65 and Python for protected-code encryption. make builds the English version; LOCALE=de make builds the German version. The orig/ directory contains the original binaries.
- A standard compile rebuilds the GEOS-bundled English and German geoWrite 2.1 binaries byte for byte; source comments remain incomplete.
- The README places new reverse-engineered work in the public domain, requests credit and asks users to respect the underlying GEOS license. The repository root has no LICENSE file.

## Primary sources

1. <https://github.com/mist64/geowrite/blob/640f1aba3a68c096c56fafc81b55772db391de35/README.md>
2. <https://github.com/mist64/geowrite/blob/640f1aba3a68c096c56fafc81b55772db391de35/Makefile>
3. <https://github.com/mist64/geowrite/tree/640f1aba3a68c096c56fafc81b55772db391de35/orig>

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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.