Source code

Version 8.2 · Last updated 22 October 2026

1. The app is free software

The Relocat app is free software. Its source code is licensed to everyone under the GNU General Public License, version 3 or (at your option) any later version (GPL-3.0-or-later). You are free to use, study, modify and share it under that licence’s terms.

The app is distributed through app stores and is combined with a few proprietary platform SDKs, such as Google Play services and Firebase. On its own, the GNU GPL may not allow either. So we grant additional permissions under section 7 of the GNU GPL for exactly those two things. They are in the file LICENSE-EXCEPTIONS next to the licence. They add to your rights; they take none away.

“The app” means the application you install on your device and the browser session interface. Both are built from the same source code.

The public repository is being prepared and will be linked here when it is published. Until then, the source code of the app is available on request, at no charge. Write to privacy@relocat.org. Source that is available only on request does not meet the free-and-open-source-software definition used by the EU Cyber Resilience Act (Regulation (EU) 2024/2847); the public repository will.

Where the EU Cyber Resilience Act (Regulation (EU) 2024/2847) applies to us, we do not claim the regime it provides for open-source software stewards.

2. The Rights Map

The Rights Map at relocat.org/map runs in your browser. The code that runs it there is free software under the same licence as the app, GPL-3.0-or-later, and needs no additional permissions. The script and style files your browser loads from https://relocat.org/static/public/rights_map/ are served unminified, each with a licence header: they are the source. The licence text is at https://relocat.org/static/public/rights_map/LICENSE.txt.

The tooling that builds the map’s geographic data, and the tests for the map, are free software under the same licence. They are not yet published; they are available on request, at no charge. Write to privacy@relocat.org.

The rules the map applies are data, not code. They are the file https://relocat.org/static/public/rights_map/data/rules.v1.json, licensed to everyone under the Creative Commons Attribution 4.0 International licence (CC BY 4.0). If you reuse them, credit “Relocat Rights Map rules data (relocat.org/map)”.

The map’s figures on German naturalisation authorities are the file https://relocat.org/static/public/rights_map/data/authorities.de.v1.json. Our compilation is licensed to everyone under the same CC BY 4.0 licence. If you reuse it, credit “Relocat Rights Map authority data (relocat.org/map)”. Each figure names its source and date. The licence covers our compilation, not the wording of the sources it cites.

The map’s geographic data comes from Natural Earth and GeoNames; their credits are on the map page. The German district boundaries come from the Federal Agency for Cartography and Geodesy: © BKG (2026) dl-de/by-2-0, Datenquellen: https://sgx.geodatenzentrum.de/web_public/gdz/datenquellen/datenquellen_vg_nuts.pdf. Data changed: we simplified and reprojected the geometry.

3. The server

The server software that runs the hosted Service is ours. We do not publish its source code, and we do not license it to anyone. It is a trade secret. The Terms of Service give you the right to use the Service; they give no rights in the software behind it. The Rights Map’s browser code, described in section 2, is the one part of relocat.org we serve under a free licence; the rest of the server software remains ours.

You do not need to trust the server to trust the Service. Your device encrypts your files, their names and the information you record about them before they leave your device, with keys derived from secrets we never hold. That encryption happens in the app, whose source code you can read, so you can check it. The server stores the encrypted items it receives and cannot read them. The Privacy Policy and the Terms of Service list what the server does see.

Up to and including version 7 of this page, we said that the server’s source code was available on request. That offer ends when version 8 of the Terms of Service takes effect; the Terms of Service page shows that date. A request we receive before that date is honoured for the revision running when we receive it, under the licence version 7 named. From that date the server’s source code is not available.

4. Protocol and documentation

The app and the server talk over a defined protocol. We intend to publish a specification of that protocol, under its own licence, so that anyone can check what leaves your device and what the server can see without reading the server’s code. A public protocol specification will be linked here when it is published.

5. Trademarks

“Relocat” is a registered trademark of Ruslan Zykun. The word mark is registered with the European Union Intellectual Property Office for the European Union and, through the Madrid system of the World Intellectual Property Organization, designated for the United States of America. The Relocat icon is our mark too; it is not registered.

The GNU GPL licenses the copyright in the app’s code. It does not license the marks. You may refer to the app by its name, say that something works with it, and say that your software is based on it. You may pass on our official builds, unaltered, under our name and icon. If you distribute a build that you compiled yourself, modified or not, you must present it under your own name, your own icon and your own application identifiers. The trademark policy that comes with the source code, TRADEMARKS.md, sets this out in full.

6. Reporting a vulnerability

To report a security vulnerability in the app or in the Service, see our Security page. Reading the app’s source code is the fastest way to check a suspicion before you report it.

7. Version

Version 8.2 (October 2026): Editorial. Section 2 adds the licence of the map’s German authority data (CC BY 4.0, our compilation only) and the credit for the German district boundaries (© BKG, dl-de/by-2-0, data changed). No change to any licence or to the status of the server.

Version 8.1 (October 2026): Editorial. Adds section 2 on the Rights Map: its browser code is free software under the GNU General Public License version 3 or later, the unminified files served from relocat.org/static/public/rights_map/ are its source, the build tooling and tests are available on request, and the rules data is licensed under CC BY 4.0. Section 3 notes that this browser code is the one part of relocat.org served under a free licence. The later sections are renumbered. No change to the licence of the app or to the status of the server.

Version 8 (October 2026): Rewritten. Version 7 said that both the server and the app were free software under the licence this page’s old address, /agpl/, is named after — version 3 or later of the GNU General Public License in its form for software offered over a network — and that the complete source of the server was available on request. No copy of the server’s source was ever handed to anyone under that licence, and nobody asked for one. Version 8 says that the app is free software under the GNU General Public License version 3 or later, with additional permissions for app-store distribution and platform SDKs, and that the server software is ours and is not published. The offer of the server’s source on request ends when version 8 of the Terms of Service takes effect; a request received before that date is honoured under the licence version 7 named. The sections on network use and on a separate licence for organisations are removed. Version 7’s sentence that source available only on request does not meet the Cyber Resilience Act’s free-and-open-source-software definition is kept, in the paragraph that offers source on request. The trademark section records the registrations. This page moved from /agpl/ to /source/; the old address redirects here.

Version 7 (September 2026): No substantive change to the licence, network-use or trademark sections. Added a sentence on the consequence of not yet publishing a public mirror under the EU Cyber Resilience Act’s free-and-open-source-software definition, and a cross-reference to the Security page for vulnerability reports.