SHSelfHostIndex

Stalwart Mail Server vs Citadel

A side-by-side comparison of two self-hosted apps from related categories — licensing, setup difficulty, resource needs, and what each one replaces.

Not the right match-up?
ST Stalwart Mail Server Modern all-in-one mail server in a single binary VS CI Citadel All-in-one groupware, mail and collaboration server
FeatureStalwart Mail ServerCitadel
CategoryMail ServersGroupware
LicenseAGPL-3.0GPL-3.0
LanguageRustC
Setup difficultyMediumMedium
Min. RAM512 MB512 MB
Deploymentdocker, binary, bare-metalbare-metal, source
GitHub stars★ 14,059★ 100
First released20201987
ReplacesMicrosoft Exchange, Google WorkspaceMicrosoft Exchange, Microsoft 365

Why pick each one

Choose Stalwart Mail Server if…

  • Single modern binary
  • Strong security defaults
Stalwart Mail Server details

Choose Citadel if…

  • Single-package setup
  • Low resource needs
Citadel details

Frequently asked questions

Is Stalwart Mail Server or Citadel better?

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

Are Stalwart Mail Server and Citadel free and open-source?

Yes. Stalwart Mail Server is licensed under AGPL-3.0 and Citadel under GPL-3.0. Both can be self-hosted at no software cost.

Can I run Stalwart Mail Server and Citadel with Docker?

Stalwart Mail Server: yes. Citadel: check the project docs for container support.

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