SHSelfHostIndex

Stalwart Mail Server vs smtp4dev

A side-by-side comparison of two self-hosted mail servers options — 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 SM smtp4dev Fake SMTP server for development email testing
FeatureStalwart Mail Serversmtp4dev
CategoryMail ServersMail Servers
LicenseAGPL-3.0GPL-3.0
LanguageRustC#
Setup difficultyMediumEasy
Min. RAM512 MB128 MB
Deploymentdocker, binary, bare-metaldocker, binary
GitHub stars★ 14,059★ 3,941
First released20202015
ReplacesMicrosoft Exchange, Google WorkspaceMailtrap

Why pick each one

Choose Stalwart Mail Server if…

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

Choose smtp4dev if…

  • Easy local testing
  • Cross-platform
smtp4dev details

Frequently asked questions

Is Stalwart Mail Server or smtp4dev better?

Neither is universally better. Stalwart Mail Server has the larger community, while smtp4dev is simpler to set up (easy difficulty). Choose based on the comparison table above and your own setup.

Are Stalwart Mail Server and smtp4dev free and open-source?

Yes. Stalwart Mail Server is licensed under AGPL-3.0 and smtp4dev under GPL-3.0. Both can be self-hosted at no software cost.

Can I run Stalwart Mail Server and smtp4dev with Docker?

Stalwart Mail Server: yes. smtp4dev: yes.

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