Citadel
PulseGate's liveness check found it on 14 Oct 2026; it has been in the index since 30 Jun 2026. How this is checked
Citadel is an open source groupware platform designed to provide email, collaboration, and content management capabilities. It is intended for deployment on a user's own hardware or in the cloud, offering organizations and individuals a way to set up a comprehensive communication and collaboration environment quickly. The system is built around a "rooms" based architecture, which serves as a unifying metaphor for its various features and is highlighted as a distinctive…
Inferred · not functionally tested
Overview
6 featuresPurpose: Providing a self-hosted, open-source solution for email, collaboration, and groupware needs.
Inferred · not functionally tested
Audience: IT administrators and organizations seeking open-source groupware
Inferred · not functionally tested
Functions: collaboration
Inferred · not functionally tested
Interfaces: API: unknown · MCP: unknown · CLI: unknown · Self-hosting: indicated (inferred, not tested)
Recorded constraints: pricing: open_source · license: Open Source · platforms: WEB · deployment: browser, windows, linux, macos, self_hosted
Constraint provenance is unknown; confirm requirements with the publisher.
Record sources: citadel.org. These links do not verify the individual claims.
In the Email & inbox space, Citadel takes a focused approach. Inferred · not functionally tested: It focuses on providing a self-hosted, open-source solution for email, collaboration, and groupware needs. Inferred · not functionally tested: It is built as an open-source project for IT administrators and organizations seeking open-source groupware. Basis unknown · not verified: Citadel is open source under the Open Source license. Basis unknown · not verified: Citadel is available on the web, Windows, Linux, and macOS, and it can be self-hosted.
citadel.org team builds and maintains Citadel. Inferred · not functionally tested: Among its 6 catalogued features are email, calendar, and contacts.
Summary written by a language model from the project’s public pages.
Tasks: Inferred · not functionally tested
- Calendar
- Contacts
- Forums
- Instant messaging
- Wiki
Topics: Inferred · not functionally tested
Built with & integrations
Trust & compliance
Indexing history
1What PulseGate has recorded for this listing
Frequently asked questions about Citadel
- What is Citadel?
- Inferred · not functionally tested: Citadel focuses on providing a self-hosted, open-source solution for email, collaboration, and groupware needs. It is catalogued under Email & inbox on PulseGate.
- Who is Citadel for?
- Inferred · not functionally tested: Citadel is an open-source project built for IT administrators and organizations seeking open-source groupware.
- Is Citadel free?
- Basis unknown · not verified: Yes — Citadel is open source under the Open Source license and free to use.
- What platforms does Citadel run on?
- Basis unknown · not verified: Citadel runs on the web, Windows, Linux, and macOS. It can also be self-hosted.
- Is Citadel still active?
- PulseGate's liveness check found it on 14 Oct 2026.
- What projects are similar to Citadel?
- Similar projects tracked by PulseGate include citadel-archive, Citadel App, and Citadel.citadel-archiveCitadel AppCitadel
- Who makes Citadel?
- Citadel is developed by citadel.org team.
- Is Citadel open source?
- Basis unknown · not verified: Yes — Citadel is open source under the Open Source license.
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