SHSelfHostIndex

Stalwart Mail Server vs isync

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 IS isync IMAP and Maildir mailbox synchronizer
FeatureStalwart Mail Serverisync
CategoryMail ServersMail Servers
LicenseAGPL-3.0GPL-2.0
LanguageRustC
Setup difficultyMediumMedium
Min. RAM512 MB32 MB
Deploymentdocker, binary, bare-metalbinary, source
GitHub stars★ 14,059★ 400
First released20202000
ReplacesMicrosoft Exchange, Google WorkspaceOutlook offline mode

Why pick each one

Choose Stalwart Mail Server if…

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

Choose isync if…

  • Released under the GPL-2.0 license
  • Written in C
  • Tiny footprint — runs in 32 MB RAM
isync details

Frequently asked questions

Is Stalwart Mail Server or isync 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 isync free and open-source?

Yes. Stalwart Mail Server is licensed under AGPL-3.0 and isync under GPL-2.0. Both can be self-hosted at no software cost.

Can I run Stalwart Mail Server and isync with Docker?

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

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