jcoffey-dev
bfda639d73
John, 2026-09-19: the fork takes a copy of the config rather than pointing at the old one, and /opt/stalwart goes away once the migration is confirmed. That turns step 4's store path from a free choice into a constraint. The step said an existing install keeps whatever its configuration names, which is true of the server and no longer true of this migration: nothing the fork runs on may sit under a directory that is going to be deleted. Worth checking before starting rather than after removing. Removing it strands nothing else. ACME account keys and issued certificates are written to the registry, inside the store, so they came across with the copy; /opt/stalwart holds the old binary, its config and its data and nothing the fork reads. What it does end is the rollback, so the new section says when. The rollback stops being one within hours anyway — after mail has flowed, going back means losing what arrived since — so the real question is how long to keep a cold copy of the pre-cutover state. The gate is the first certificate renewal, which is the one check in "The first week" whose failure would send anyone back; forcing a renewal closes it in a day rather than ninety. Archive the store off-host before removing the directory.
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, anddocs/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.