Open365: A Self-Hosted Office Stack That Tried to Do It All
There was a time when Open365 looked like the dream stack — email, document editing, file sync, calendar, and contacts, all in one place, all open source. No licenses, no subscriptions. Just spin it up and go. That was the pitch.
The project didn’t stick around long. But it left behind something interesting — a blueprint for building a full-featured, self-hosted collaboration suite from open components. For teams that want to host everything themselves, even today, that blueprint can still be useful.
What Was Inside the Stack
| Part of the System | What It Handled |
| LibreOffice Online | Edit Word, Excel, and PowerPoint docs straight from the browser. |
| KMail Webmail | Integrated email with filters, IMAP support, and folders. |
| OwnCloud Backend | Sync, store, and share files across users and devices. |
| Calendar & Contacts | Manage scheduling with CalDAV, store contacts with CardDAV. |
| Cross-Platform Sync Client | Keep files up-to-date on Windows, macOS, and Linux. |
| Docker Deployment Option | Run the whole thing in containers, if preferred. |
Why Some Still Talk About It
Even though Open365 isn’t maintained anymore, it nailed a few things:
– It wasn’t just document editing — it pulled in real email and calendars.
– It let users work entirely in-browser, or sync files to local folders.
– Unlike many open alternatives, it aimed for feature parity with Office 365.
– It bundled everything in one login, one dashboard — no jumping between tools.
Rebuilding Something Like It Today
Open365 itself is gone. But a similar stack can still be put together — with more effort. Here’s roughly how sysadmins recreate the idea:
Setup Overview
1. File Storage & Sync — Use Nextcloud or ownCloud. Both offer user management, file sharing, and sync clients.
2. Document Editing — Plug in Collabora Online (for LibreOffice compatibility) or OnlyOffice Docs.
3. Email Services — Set up Postfix (SMTP) and Dovecot (IMAP) with a webmail client like Roundcube or Rainloop.
4. Calendars and Contacts — Most Nextcloud forks already have these built-in, using CalDAV/CardDAV protocols.
5. Access Control and SSL — Use Nginx or Apache as reverse proxy, apply HTTPS with Let’s Encrypt, configure user auth (LDAP or Nextcloud SSO).
6. Packaging It All Together — Some forks or community bundles include prebuilt docker-compose.yml files. Otherwise, expect to stitch things together manually.
System Requirements
– 2+ vCPUs, 4–8 GB RAM minimum
– 20+ GB storage (scales with user data)
– Linux server (Ubuntu/Debian preferred)
– Moderate experience with Docker, mail servers, and reverse proxies
What to Watch Out For
– High Resource Demand: Real-time document editing (especially LibreOffice-based) is not lightweight.
– No Centralized Updates: You’re managing and securing each part individually.
– Discontinued Project: Open365 proper is unmaintained. You’ll be relying on replacements and forks.
– Integration Complexity: If you want a unified experience, you’ll need to do some glue work.
Still Worth It?
If the goal is to own your full collaboration stack — no vendor, no cloud, full control — then yes, it’s still worth considering a setup like Open365. Not as a turnkey install, but as a concept.
Some IT teams use parts of it in production, especially for internal teams or privacy-sensitive use cases. Just don’t expect plug-and-play.
