jcoffey-dev
efe0b01bac
Two decisions §2 implied but never settled. §2.4 said no "Stalwart" in UI text; §2.6 requires the startup banner, the JMAP implementation string and OpenTelemetry's service.version to name the base. Taken literally, the first would strip exactly what the second exists to keep. Version and build metadata are now exempt, with the distinction written down: §2.4's first bullet governs identity, the new one governs provenance. A second bullet covers material outside the product. The name appears with its trademark attribution; the fork relationship is stated once in the provenance or license section; the migration path names the server it migrates from, because an operator searching for it has to find it. The base version stays out of taglines, page titles and social previews, where it reads as a source identifier rather than a fact. No comparison in either direction: what INBUXA offers is stated on its own terms. §2.6 said the base drops out of the version string "when it happens", which left someone judging the moment. The trigger is now the first release that isn't a rebase on an upstream tag. Because the reason for publishing the base is one-way store conversion, and that outlives the string, the amendment routes it to the upgrade documentation rather than letting it go. §8 no longer asks whether the fork follows upstream's version numbers. §2.6 answered that on 2026-09-18: it has its own.
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.