Skedz is an offline-first Progressive Web App (PWA) for viewing, filtering and personalizing conference schedules.
It was created during the 39C3 congress as an open source experiment to explore whether a fully client-side, self-managed schedule app can work reliably without any backend server.
Skedz is inspired by Calendify schedules, but runs completely locally on the user’s device.
| Format | Extensions | Description |
|---|---|---|
| JSON (schedule.json) | .json |
JSON format used by Frab, Pretalx, and others |
| XML (schedule.xml) | .xml |
XML format used by Frab, Pretalx, Pentabarf, and others |
| XCal | .xcal, .xcs |
XML-based iCalendar format |
| iCal | .ical, .ics |
Standard iCalendar format |
- PWA: https://app.skedz.org
- Project website: https://skedz.org
If not available yet, install Node.js (LTS version recommended), npm, and git. For example, on Debian/Ubuntu:
sudo apt update
sudo apt install nodejs npm gitThen clone the repository:
git clone https://github.com/ysorge/skedz.git
cd skedz
npm installStart a local development server with hot reload:
npm run devOpen the URL shown by Vite (usually http://localhost:5173).
Build the production version including service worker support:
npm run build
npm run previewThen open the preview URL (typically http://localhost:4173).
You can install the app from the browser menu ("Install app").
Note: Opening the built files directly via file:// will not work correctly because service workers require HTTP.
- Load frab-compatible
schedule.jsonendpoints (e.g. congress Fahrplan) - Platform-independent PWA (mobile & desktop)
- Offline-first: schedules and personal choices are stored locally
- Grouped-by-day session list ordered by time
- Filters: track, day, room, type, language, search term
- Timezone handling: view schedule in event timezone or convert to device timezone
- Multiple view modes: compact table, detailed list
- Like sessions to build your own schedule
- Session detail screens with full description
- Local notifications for liked sessions (local reminders)
- Export of liked sessions (iCal/JSON/CSV)
The app shell is cached by the service worker. Schedules are stored in an IndexedDB after loading from URL or importing a file. On next launch (even offline), the cached schedule loads instantly.
You can share a schedule by adding a ?url= parameter to the app URL. This automatically loads the schedule from the specified endpoint. Example:
https://app.skedz.org/?url=https://api.events.ccc.de/congress/2025/schedule.json
This is useful for sharing schedules with others or bookmarking schedules.
Some schedule endpoints don't allow browser access due to CORS (Cross-Origin Resource Sharing) restrictions. If loading fails with a CORS error, you have two options:
- Download and import manually: Download the schedule file and import it via "Import file".
- Use a CORS proxy: Deploy the companion Skedz CORS Proxy or use another CORS proxy and use it to access CORS-protected schedules.
Example with CORS proxy (here hosted at https://cors.skedz.org):
https://app.skedz.org/?url=https://cors.skedz.org/https://fosdem.org/2026/schedule/xml
The proxy adds the necessary CORS headers and includes a domain whitelist for security.
Skedz is intentionally hackable. Ports, integrations, and other side projects are welcome.
A webxdc port to use Skedz inside chats (Delta Chat). View conference schedules and share liked sessions with everyone in the chat.
- App on webxdc.org: https://webxdc.org/apps/#link2xt-skedz
- Source code: https://codeberg.org/link2xt/skedz
- Delta Chat: https://delta.chat/
Community project by link2xt.
Skedz is a community-driven, open source side project. The focus is robustness, offline usability and transparency — not feature parity with native apps. Contributions, feedback and issues are very welcome.
Pull requests are welcome! Please open an issue first to discuss what you would like to change.
GNU Affero General Public License v3.0 (AGPL-3.0). See LICENSE for details.
Skedz was created by Yves Sorge during 39C3.