Doc2Lib SlotWatch, a watcher for Doctolib appointments

In May 2026 I wrote Doc2Lib SlotWatch, a small web app for Doctolib. It watches for appointments that become free and sends the booking link within a minute. The app is the port of an older Google Sheet with Apps Script that has been running for a while. It is a private tool, one instance per person, costs nothing and has no connection to Doctolib.

The screenshot below shows the start view, the list of jobs, here one job for orthopedics in Stuttgart. The app itself is in German.

Doc2Lib SlotWatch, the list of jobs

How a search works

Doctolib is an online booking service for doctor’s appointments. A job names a specialty, a place, a radius and a time window in days. The defaults are 20 km and 14 days. A 30-minute lockout stops repeated messages about the same doctor.

Every minute the app asks Doctolib for the doctors near the place and checks their free slots. When a slot falls into the window, the app sends a message over Telegram. If a mail address is set, it also sends a mail. The message names the doctor, the place and up to five slots, plus a link into the booking.

Inside a job the doctor list shows every doctor Doctolib returned, sorted by distance. Nur diese Ärzte limits the search to the selected doctors, and Gesperrte Ärzte skips the listed ones. The Termine view keeps the hits of the last hour with their booking links, and the Verlauf view lists the runs.

One instance per person

Every person gets a separate worker with a separate database, because appointment searches are health data. The app stores only the jobs, the doctor lists, the hits of the last hour and a three-day log. It needs no Doctolib account and books nothing. On the phone you can put the app on the home screen.

The sheet holds one search in fixed cells. The web app holds several jobs, a doctor list that survives the runs and the history. It is plain JavaScript without a framework and runs as a Cloudflare Worker with a D1 database and a cron trigger every minute.