Self-hosted / open sourceScheduling & BookingHeadquarters: DE

Baïkal: sovereignty score and 8 European alternatives

Baïkal is a lightweight CalDAV and CardDAV server for calendars and contacts. It offers a web interface for managing users, address books and calendars, and works with clients such as iOS, macOS, DAVx5 on Android and Mozilla Thunderbird. Data can be stored in MySQL, PostgreSQL or SQLite, and the server runs on a basic PHP-capable web server. An unofficial Docker installation is also documented.

Baïkal is developed by fruux GmbH in Münster, Germany, together with Net Gusto and other contributors, and is released under the GNU GPL v3 licence. Organisations install and run the software on their own server, and the project's pages describe no vendor-hosted service. For a European organisation this makes it a self-hosted alternative to cloud calendar services from non-European providers, provided the organisation operates and secures the server itself.

See the 8 European alternatives ↓Assess your stack with Baïkal pre-selected

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Sovereignty score

94 / 1000 = high exposure
100 = sovereign

Jurisdiction SOV-2100
Headquartered in the EU: European law applies
Data residency SOV-3100
EU-only hosting
Cryptographic key sovereignty SOV-390
Self-hostable: encryption keys under your own control
Freedom from lock-in SOV-680
Open source: low switching costs
Source & runtime sovereignty SOV-4 · SOV-6100
Source code auditable, forkable and self-hostable

SOV codes: the matching objective in the European Commission's Cloud Sovereignty Framework. Official source

How the score is calculated

Facts and evidence

Last checked October 12, 2026

Headquarters	DE (EU)Verified by hand
Sovereignty model	Open-source, distributedVerified by hand
Data hosting	EUVerified by hand
Open-source	YesVerified by hand
GDPR-compliant	NoVendor-stated
Category	Scheduling & Booking
Type	Product
Website	sabre.io ↗

How we verify · Something wrong? Suggest a correction

Top EU-based & GDPR-compliant alternatives to Baïkal

The European alternatives to Baïkal come from our knowledge base of over 7,800 vendors. We only list vendors headquartered in the EU or the EEA; fully European-owned vendors rank before vendors with a foreign owner. For each alternative you see the country, the open-source status and a short description.

Score per alternative: 0 = high exposure, 100 = sovereign

57 European Scheduling & Booking vendors are in the catalogue. View the whole category · Submit an alternative · View category on the map

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Why digital sovereignty matters with Baïkal

Baïkal is headquartered in DE and therefore falls under European law: the GDPR, NIS2 and the Data Act. No foreign legislation can compel access to your data.

Data is hosted exclusively in the EU, so Baïkal scores best on data residency.

Baïkal is open source. You can audit the source code, self-host the software and keep the encryption keys under your own control. Switching is easier because data and software are not tied to a single party.

What this means for your organisation depends on your whole stack and context. The free assessment weighs Baïkal together with your other vendors and gives a total score, a heatmap and the main risk drivers.

Frequently asked questions

What is the best European alternative to Baïkal?

It depends on your use case. Strong EU alternatives to Baïkal include Agendize, aleno and Billetto. On this page you can compare 8 EU alternatives by jurisdiction, data residency and open-source status.

Are there open-source alternatives to Baïkal?

Our list of EU alternatives to Baïkal is mostly commercial options. Browse the category on the map for open-source choices.

Is Baïkal GDPR-compliant and where is the data hosted?

Baïkal is headquartered in DE (EU) and hosts data in EU. It is also open-source, so you can self-host it. That makes Baïkal an EU-sovereign choice in its own right; the EU alternatives on this page are comparable European tools.

Details and sources

Verified by handHeadquarters, owner, hosting locations and licence have been checked by us against public sources. Free of charge and for every vendor, not a paid label. Nothing in this knowledge base is taken over automatically. Last checked on October 12, 2026.

Sources

Public sources used in the latest check of this record.

Compliance evidence

The links below point to the vendor's own public documents. We only record what we found: a missing link means "not found publicly", not "not compliant".

No public compliance evidence has been recorded for this vendor yet. Do you know its DPA or subprocessor list? Something wrong? Suggest a correction

Digital sovereignty in Scheduling & Booking

Scheduling & Booking: Appointment scheduling, online booking systems and calendar management. In this category the choice of vendor determines who has legal access to your data, where that data lives and how easily you can switch later.

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