Thunderbird Appointment vs EteSync

A side-by-side comparison of two self-hosted calendar & contacts options — licensing, setup difficulty, resource needs, and what each one replaces.

Not the right match-up?
FeatureThunderbird AppointmentEteSync
CategoryCalendar & ContactsCalendar & Contacts
LicenseMPL-2.0AGPL-3.0
LanguagePythonPython
Setup difficultyMediumMedium
Min. RAM512 MB256 MB
Deploymentdocker, sourcedocker, bare-metal
GitHub stars★ 547★ 1,765
First released20232017
ReplacesCalendly, DoodleGoogle Calendar, iCloud

Why pick each one

Choose Thunderbird Appointment if…

  • Released under the MPL-2.0 license
  • First-class Docker support for quick deployment
  • Written in Python
  • Lightweight — runs in 512 MB RAM
Thunderbird Appointment details

Choose EteSync if…

  • Released under the AGPL-3.0 license
  • First-class Docker support for quick deployment
  • Active community (1.8k GitHub stars)
  • Written in Python
EteSync details

Frequently asked questions

Is Thunderbird Appointment or EteSync better?

Neither is universally better. EteSync has the larger community; both share a medium setup difficulty, so the decision comes down to features and licensing.

Are Thunderbird Appointment and EteSync free and open-source?

Yes. Thunderbird Appointment is licensed under MPL-2.0 and EteSync under AGPL-3.0. Both can be self-hosted at no software cost.

Can I run Thunderbird Appointment and EteSync with Docker?

Thunderbird Appointment: yes. EteSync: yes.

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