jcoffey-dev 7196f9dda2 Specs: when the source goes out, and who owes the offer
AGPL section 13 starts at the cutover, not at the announcement: the fork is
a modified AGPL program and its users reach it over a network. Settled
today that the source is released after the cutover, with the links live
then, and in the meantime the server's users are the operator's household,
so the people owed an offer and the people holding the repository are the
same people.

Anyone migrating their own server inherits that obligation on their first
day and has no such overlap, so the migration tool says so at the end of a
successful run instead of leaving it to be discovered.
2026-09-19 22:58:30 -07:00
2026-09-18 10:21:56 -07:00
2026-09-18 10:21:56 -07:00
2026-09-18 10:21:56 -07:00

inbuxa

A complete mail and collaboration server, every feature included, under the AGPL


INBUXA is a mail and collaboration server: JMAP, IMAP, POP3, SMTP, CalDAV, CardDAV and WebDAV, in one Rust binary, with ihasmail as its web front end. It is a fork of Stalwart. Project site: inbuxa.org (not up yet).

Stalwart ships some features only in a paid Enterprise Edition: multi-tenancy, masked email, undelete and others. INBUXA ships everything to everybody under the AGPL-3.0, rebuilding those features independently and without using any of Stalwart's Enterprise code.

Status: in development, not released. The fork builds, passes its unit tests, and runs as a working mail server. The Enterprise features are being specified and haven't been rebuilt yet. Don't run it in production.

What's different from Stalwart

  • Every feature, one edition. No license key, no edition checks, no upsell. See docs/spec/SPEC.md §4 for the features being rebuilt, and docs/spec/features/ for each one's specification.
  • Webmail and administration by ihasmail, as a separate service that can run beside the server or elsewhere. Stalwart's own web interface is removed, so there's no web front end on the mail host.
  • Clean-room rebuilds. Enterprise-only code is stripped from every upstream release before it's imported. The rebuilt features are written from specifications that use only public sources (docs/spec/SPEC.md §3).

How the fork is kept

Upstream releases arrive as stripped snapshots, never with upstream's git history, which contains Enterprise code. tools/fork/strip.py builds each snapshot on top of upstream's own ossify.py, then verifies it independently. The report for every import is in docs/fork/strip-reports/. See docs/spec/SPEC.md §2.

Building

cargo build --release -p inbuxa          # the binary is target/release/inbuxa
docker build -t inbuxa .                 # or the container image

Settings are read from INBUXA_* environment variables. An existing Stalwart install's STALWART_* variables still work, with a warning to rename them. New installs keep their data in /var/lib/inbuxa and logs in /var/log/inbuxa. Existing installs keep the paths their configuration already names, so none of their data moves.

License and credits

INBUXA is free software under the GNU Affero General Public License, version 3.

It is a fork of Stalwart, copyright © Stalwart Labs LLC. Upstream's copyright notices are kept on every file they cover. Stalwart's files are dual-licensed AGPL-3.0-only or Stalwart's Enterprise License, and INBUXA takes them under the AGPL-3.0 only. A few of those files also carry code from other projects under MIT or BSD licenses, which stays under those licenses; THIRD-PARTY.md lists it with its notices. "Stalwart" is Stalwart Labs' name. INBUXA isn't affiliated with or endorsed by Stalwart Labs.

The INBUXA mark reuses ihasmail's cat-and-envelope artwork.

S
Description
Imported from github.com during the 2026-09-20 standup (local dir: inbuxa-server)
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