Already have an ONLYOFFICE connector?

Keep the connector. Change the editor behind it.

Nextcloud, Mattermost, ownCloud, Seafile, Alfresco, Moodle, Confluence, Jira, Redmine and many more ship a connector for ONLYOFFICE Docs: an administrator enters a server address and a secret, and files open in the browser. The SumOffice compatibility server answers that same API. Point the connector at it, and .docx opens in SumDoc, .xlsx / .xlsm / .xlsb in SumSheet and .pptx in SumSlide — every save goes back to your system as a new version. Nothing in your system is patched.

What you get

Three steps

1. Run the server

docker pull hissih/sumoffice-compat:2026.4.0.6
# the kit's docker-compose.yml runs the server and the three editors behind one port
JWT_SECRET=$(openssl rand -hex 24) docker compose up -d
docker compose exec compat node /app/compat-doctor.mjs --server http://127.0.0.1:8080 --secret "$JWT_SECRET"

The doctor runs exactly what connectors run when you press Save in their settings: the health check, the signed version command, the refusal of an unsigned one, and a test conversion with the result downloaded. Four green checks, and your system will accept the address.

2. Enter the address and the secret in your connector

Open the ONLYOFFICE settings of your system — the place where the document server address used to be. Enter the compatibility server’s https address and the same secret, then save: the connector checks the connection itself. Nothing else changes; accounts, permissions and versions stay in your system.

3. Open a file

Click the usual open button in your system. A .docx opens in SumDoc, an .xlsx, .xlsm or .xlsb in SumSheet, a .pptx in SumSlide — right inside the system’s page. Every save goes back to the system as a new version of the file.

Put the server under the same site as your system — cloud.example.com and office.example.com — and serve it over https: the editors run inside your system’s page and need a secure, first-party context there.

Systems

Tested live: Nextcloud, Mattermost, Seafile CE, ownCloud and Moodle — opening, editing and saving; see the records below. Every other system in the table is compatible through the ONLYOFFICE interface — we will check it on your own stand within one day.

* Cloud services call the document server from the internet: the compatibility server needs a public https address for them.

Record: Mattermost

Mattermost 11.11.1 Team Edition with the ONLYOFFICE plugin 2.3.0, unmodified. Plugin settings: the server address, the shared secret, and the plugin’s default JWT header AuthorizationJWT. A DOCX attachment in a channel opens in SumDoc; a sign-off line is typed and saved; the plugin confirms the save under the attachment, and the file in Mattermost carries the line. The same with a PPTX attachment in SumSlide.

Record: Nextcloud

Nextcloud 35.0.1 with the ONLYOFFICE app 10.2.1 from the app store, configured the standard way. The app’s own connection check passes (“version 8.3.1.1 is successfully connected”). A DOCX opened from Files in SumDoc and an XLSX in SumSheet: typed, saved, and a new file version appears in Nextcloud with the edit inside it. Prefer Nextcloud’s own Office app? That path is measured too — Excel and Word in Nextcloud.

Record: Seafile CE

Seafile CE 14 — tested on 18 October 2026: Word, Excel, PowerPoint and macro-enabled Excel files open, are edited and saved; macros are preserved.

Seafile CE 14.0 with its built-in ONLYOFFICE integration, configured the standard way. A .docx, an .xlsx, a .pptx and an .xlsm were opened from a library, edited, saved back to Seafile, downloaded again and opened in Microsoft Office — the edit is inside each file. In the .xlsm the VBA project is byte-identical to the original after the save (same SHA-256).

Record: ownCloud

ownCloud 10.15 — Word, Excel and PowerPoint files open, are edited, saved and open again with the edit inside.

ownCloud 10.15.3 Community with the ONLYOFFICE app 10.0.0 from ownCloud Market, unmodified, configured the standard way; the app’s own check says “successfully connected”. A .docx in SumDoc, an .xlsx in SumSheet and a .pptx in the presentations editor were opened from Files, edited, saved, closed and opened again: every save is a new file version in ownCloud with the edit inside it, and the reopened file is the saved one. Server release 2026.4.0.6 also hands the save back straight away when ownCloud opened the editor twice and the first window never connected — before, such a save reached ownCloud only after 20 minutes of idle time.

Record: Moodle

Moodle 5.3 — Word, Excel and PowerPoint files open from a course, are edited, saved and open again with the edit inside.

Moodle 5.3 with the ONLYOFFICE activity module 6.1.0 from the Moodle plugins directory, unmodified. Saving the module settings runs its own check (health check, version, a test conversion), and it passes. A course with three activities: a .docx in SumDoc, an .xlsx in SumSheet, a .pptx in the presentations editor — each opened from the activity, edited, saved, closed and opened again; the edit is inside the file in Moodle’s own file storage. Macro-enabled workbooks (.xlsm) the Moodle module itself opens for viewing only. Server release 2026.4.0.6 adds a fix for Moodle sites that the server reaches by an internal address: Moodle answers such requests with a redirect to its public address, and files now download and saves arrive. Setting it up in Moodle →