Self-Hosted Calender System for Scheduling Appointments based on Timeslots, similar to 'Calendly'

Question

Is there a free, open source appointment scheduling-system similar to Calendly where I can predetermine timeslots for others to choose?

And if one person selected a timeslot, then that timeslot is visible as reserved or blocked for others.

I would like to have a self-hosted alternative to Calendly, perhaps based on PHP/MySQL.

I already tried Easy!Appointments, but a "dependency hell" (via NodeJS / npm) made me download an additional 32.000 documents (!), which in turn led to errors during the more-than-an-hour-long FTP upload, which ultimately meant that I could not use it.

Answer 1

Another system to look at is BookedScheduler. This link is for the last open source version, as it has now become a SaaS. It will probably have more than you require, but if configured properly can do the job. Also see a demo here