Release Notes 2026.06.1

The release notes highlight the most important changes – feel free to check out the detailed logs at GitHub.

grommunio 2026.06.1 is the largest release to date. Over a year of work reaches across the whole stack — from the C++ mail engine up to the boot ISO — with the guiding principle unchanged: you stay in charge of your own infrastructure. Mail, calendars, files, meetings, identities and, new in this release, your AI, all run on hardware you control, with nothing forced through someone else’s cloud.

Highlights

• grommunio AI — an assistant inside grommunio Web, with your choice of model and where it runs (cloud or fully local).
• gromox — a lighter, faster engine: per-mailbox information-store workers, IMAP4rev2 (RFC 9051), a much-expanded EWS, and a from-scratch Offline Address Book.
• Shared mailboxes on mobile — grommunio-sync now does impersonation over Exchange ActiveSync.
• Rebuilt admin — the Admin Web interface is now fully TypeScript, with per-domain DKIM key generation from the UI.
• A refreshed suite — Meet (managed TURN relay), Files (new generation), Archive 1.4, Keycloak 26.6.4 and Desk 1.2.
• A fresh platform — the whole appliance rebuilt on openSUSE Leap 16.0, plus native Debian/Ubuntu .deb packages for the entire stack.

grommunio AI

The headline addition is grommunio AI, an assistant that lives inside grommunio Web. It can summarise a single mail or a whole thread, translate messages, and help you write — draft a reply, adjust its length or tone, fix the grammar. Smart Actions turn a mail into a meeting invitation, a task, a contact or a reply; each opens a pre-filled dialog, and nothing happens until you click.

What sets it apart is that you decide which model runs it, and where. grommunio AI speaks both the OpenAI-compatible and Anthropic API standards, which between them cover:

• free cloud tiers — Google Gemini (the shipped default), Groq and OpenRouter
• commercial APIs — OpenAI, Anthropic/Claude, Mistral, Azure OpenAI and the rest
• local models you host yourself — Ollama, LM Studio, vLLM, llama.cpp or LocalAI

Point it at a local Ollama setup and nothing leaves the building — no key, no outbound call, no third party reading your mail. Privacy was built to match: the plugin ships switched off; an admin must enable it, after which every user still opts in individually; all calls happen on the server and the API key stays in the server config where the browser never sees it. The one caveat: pointed at a cloud provider, the text you are working on does go to that provider — which is exactly why the local, nothing-leaves option is a one-line change away.

gromox: a lighter, faster engine

• Lower memory — the information store can split itself up, running a small worker process per mailbox under a lightweight director instead of one ever-growing process. Joined by a heap reaper that returns unused memory on a schedule, tighter IMAP-daemon limits, a shorter idle-cache timeout and a stack of plugged leaks, the result is simple: the server holds onto less memory, so more mailboxes fit on the same box.
• IMAP4rev2 (RFC 9051) — gromox is now one of the few open-source groupware servers to implement it: advertised behind the ENABLE handshake, with ESEARCH, LIST-EXTENDED, server-side MOVE, saved search results, UTF-8 mailbox names and the cleaner status/response codes.
• Exchange Web Services — greatly expanded: tasks, calendar occurrences with proper timezones, real delegate management with permission levels, and the full meeting workflow (invitations, cancellations, responses, and a server-side processor that keeps the organiser’s calendar in step), plus streaming notifications and room/people lookups.
• Offline Address Book — a brand-new, from-scratch implementation of Microsoft’s OAB format and its LZX compression, built and served by gromox itself, with no Microsoft code in it.
• Better body rendering — HTML/RTF/plain-text conversion can hand off to Pandoc and Chawan for higher fidelity, and the in-house RTF reader was overhauled for CJK text, right-to-left scripts and nested tables.
• Notable fixes — Outlook no longer loses appointments when opening a shared calendar; Outlook 2010 can log in again under OpenSSL 3; AutoDiscover stopped advertising a non-existent OWA endpoint (which had quietly broken Thunderbird setup); recurring meetings keep their timezones straight. The import and export tools were also renamed gromox-import and gromox-export.

grommunio Web

Besides being the new home of grommunio AI, the web client kept getting polished where it counts — composing, S/MIME, search and theming — the steady work that keeps it the most capable open-source Exchange web client around.

Shared mailboxes on mobile, at last

grommunio-sync now supports impersonation over Exchange ActiveSync, so a shared or functional mailbox can be put on a phone with full rights, signing in with your own account — something Exchange and Microsoft 365 do not offer over ActiveSync. gromox’s AutoDiscover understands the combined sharedmailbox!user login and enforces it server-side, checking both who you are and whether you hold owner rights on the target, so the phone is set up straight against the shared store. As a safety net, a remote wipe on an impersonated session is dialled back to account-only, so nobody wipes a personal device by accident.

A rebuilt admin, and DKIM out of the box

• The Admin Web interface has been rebuilt in TypeScript — the whole codebase moved over, file by file, to a strictly-typed setup with no JavaScript left behind, for fewer runtime surprises and a console that is far easier to work on and contribute to.
• DKIM is now handled for you: generate a per-domain signing key right from the Admin UI and grommunio hands back the public record to paste into DNS — no more fishing around with rspamadm and openssl. This release also sorted out default and anonymous permissions on public folders and tightened several directory-integration paths. Once your records are published, grommunio’s existing DNS health check confirms whether SPF, DKIM, DMARC, MX and the rest line up.

The rest of the suite

• grommunio Meet — a big refresh, including a central managed STUN/TURN relay (turn.grommun.io) for self-hosters who can’t run their own, with a fallback over port 443 that looks like ordinary HTTPS and nearly always gets through; the whole Jitsi stack moved to a current build on JDK 17, and lobby and breakout rooms are on by default. You can still point it at your own coturn.
• grommunio Files — up a full generation: fresher, faster and more secure, with built-in collaborative in-browser editing of office documents, grommunio branding and single sign-on, and in-place self-upgrade of older installs. The self-hosted answer to OneDrive and SharePoint.
• grommunio Keycloak — moved to Keycloak 26.6.4, the identity provider behind single sign-on across Web, Admin, Files and Meet from one grommunio login; its configuration now lives under /etc, so settings survive upgrades.
• grommunio Archive 1.4 — overhauled for the Leap 16.0 / PHP 8 base and running as a regular service: a web interface for searching and reviewing mail, full-text search underneath, and an SMTP listener that copies messages as they pass through — on top of archiving and retention rules, legal hold, deduplication, fingerprinting and verification, tagging, export/restore, audit logs, direct IMAP import, and bulk import from sources like Google Workspace and Microsoft 365.
• grommunio Desk 1.2 — spell checking from your system languages, server-view zoom with reset, a right-click context menu (spelling suggestions, copy/paste), isolated per-server sessions, editable server names and a reload option, clearer title-bar icons, automatic settings migration on an updated Electron base, and assorted fixes (URL validation, macOS shortcuts, the server-view loading state, dialog buttons).
• grommunio DAV — can now publish the company Global Address List as a read-only CardDAV address book, and remembers per-folder CalDAV/CardDAV settings, so calendar colours and ordering set in Apple Calendar finally stick. grommunio Index 1.6 made server-side full-text search more configurable and steadier under load.

A fresh platform: openSUSE Leap 16.0

The whole appliance was rebuilt on openSUSE Leap 16.0 — a current, maintained base with a newer kernel, toolchain and crypto stack. And it is not only the VM image: every guided install target moved to 16.0 — the VMware/OVA appliance, the install ISO, the offline all-in-one ISO for air-gapped sites, and the container/compose stack (now Leap 16.0 with MariaDB 11 and de-privileged). Networking switched to systemd-networkd, and grommunio-setup is now safe to re-run, so roles can be added or removed on a live system without a clean reinstall — on both 15.6 and 16.0.

Debian, properly this time

With 2026.06.1 there are native .deb packages for the whole stack — the gromox engine and every front-end — built the proper Debian way. The setup tooling learned to work out what it is running on and do the right thing: write apt sources, import signing keys into the keyring, and drive apt on Debian 13 and Ubuntu 24.04 and 26.04 LTS, right next to openSUSE and RHEL. The packages are reaching general availability deliberately, one component at a time and with selected partners first, so each one is proven before it goes out to everyone.

Documentation, rebuilt

docs.grommunio.com has been rebuilt from the ground up on a modern static-site stack, with fast search across every page and a clean split into User, Administration and Development sections. New material includes a high-availability clustering guide, a Kerberos single sign-on walkthrough for transparent domain-joined Outlook logins, a fuller Exchange-to-grommunio migration guide, and a rewritten container chapter for Leap 16.0.

Supported Distributions

As of 2026.06.1, grommunio supports installation and operation on:

• openSUSE Leap 16.0 / SLES 16 (appliance base)
• Debian 13
• Ubuntu 26.04 LTS

Update

Existing installations update through the usual grommunio update process; see Updating grommunio.

Acknowledgements

A big thank-you to the customers and partners whose feedback shaped this release, and to everyone who builds grommunio out in the open. Join the discussion in the grommunio community.