In cluster rehearsal 3, turning outboundMta off on node1's role was
reported applied (x:settingsReload applied: true), yet node1 kept
delivering mail, a report message included, until it was restarted.
The queue and report managers were started at boot only when the
node's role included outboundMta (crates/smtp/src/lib.rs), and the task
manager only when the role had some task type (spawn_task_manager).
After that nothing looked at the role again: a queue manager that was
running kept claiming and delivering, and one that wasn't never
started.
They now start on every node (outside recovery mode) and follow the
role live:
- Queue manager: before each scan it reads the role from the running
settings. Without outboundMta it claims nothing new; deliveries
already running finish and report back as usual, which releases
their locks. When the role comes back (a reload wakes the manager
with ReloadSettings, and it looks again every 30 s regardless) it
logs queue.started and scans the whole queue at once.
- Report scheduler: DMARC and TLS report events are handled only while
the role has outboundMta, as at boot; events arriving without it are
dropped, as they were on a node started without the role.
- Task manager: task_enabled already read the current role on every
scan. It now also runs on nodes whose role has no task type (the
scan returns at once until one is added), a job claimed before a
role change is handed back at once rather than run or held until
its lease lapses, and a settings reload wakes the manager so a role
that gained task types starts claiming them straight away.
Starting the queue manager on every node also drains the queue channel
on nodes without outboundMta. Upstream left that channel unread, so
each message queued there parked a refresh in it, and by the code,
queueing would block once 1024 had piled up (not reproduced here).
A role object edit reaches the nodes that name that role in
INBUXA_ROLE. Moving a node to another role still means changing its
environment, and so a restart. Listener changes in a role still need a
restart too (listeners bind at boot); this change is about tasks and
delivery.
cluster::live_roles::live_role_tests (new; PostgreSQL, two nodes over
one store):
1. A node started with outboundMta delivers and runs a TLS report
task; after its role loses outboundMta and the settings reload, a
new message isn't attempted and a new report task stays pending;
with the role back, both are taken up.
2. A node started with no task type at all gains outboundMta: a
waiting message is attempted and a report task runs.
On main the test fails at step 1 ("delivery attempted without
outboundMta"); with step 1 bypassed, step 2 fails (nothing picked the
message up in 20 s).
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. Documentation: docs.inbuxa.org.
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.
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 aren't read: the server stops at startup and
names each one to rename.
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, modified by Coffey Labs in 2026. Upstream's copyright notices are kept on every file they cover, and every upstream file this fork changed says so in its header, under the notice it came with. 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.