SOGo 6 - September News

September 29, 2025

Dear SOGo community,

Dear Community, it is with great pleasure to share with you news about SOGo 6, the complete refactor of SOGo 5. A lot of progress has been made and communications like this one will be more frequent.

SOGo 6

If you miss the announcement back in February at the FOSDEM, the next big version of SOGo will be a completely new webmail. Indeed, the current design and technology of SOGo 5 make its maintenance, updates, and the addition of new features increasingly difficult over time. SOGo 6 is made from scratch and will cover all the functionalities of SOGo 5 and more. Still open-source and free, under GPL license.

What to expect with the first SOGo 6 release

The goal of the first SOGo 6 release is to cover all SOGo 5 functionalities and be ready to get new features. Let’s review all of this!

Techno and design

• SOGo 5 was using AngularJS and Objective-c. SOGo 6 now uses Python for its backend and Reactsjs for its frontend.
• The frontend and backend are now completely separated.
• The backend uses Flask and will serve a RESTful API.

Basic modules

• As for SOGo 5, SOGo 6 manages mails, calendars and address books

Mail interfacing

• SOGo 6 reads mail server (imap) and manages filtering (sieve) and outgoing mail (smtp).

Desktop software interfacing (outlook, thunderbird…)

• SOGo 6 still is a caldav/cardav server.
• For performance and troubleshooting reasons, support for ActiveSync will be removed and replaced by another Microsoft protocol: MAPI over http

User resource and SSO

• SOGo 6 reads the same user source, ldap or sql.
• SOGo 6 manages the same SSO: openid, saml2, cas.

Admin tool

• SOGo 5 was using a CLI command sogo-tool. SOGo 6 drops that to have a proper admin API.

New things

• SOGo 6 embarks a new process called Agent. It runs a tasks queues, using Celery and Redis, the new cache system. This agent will allow new features and tasks planification like : scheduling the sending of a mail or having a few seconds to cancel a sending.
• A brand new configuration system. Instead of a long sogo.conf file, SOGo 6 now has a proper admin interface to configure it.
• Multi-domains management has been reviewed to make it easy.

Migration from SOGO 5

Even though the SOGo 6 application is completely new, migration from SOGo 5 will be supported and will be carried out as smoothly as possible.

• The cache server Memcached is replaced by Redis
• SOGo’s database - for calendar, address books, user’s preferences… - has changed with SOGo 6. Table’s has been completely redone and PostgreSQL is required. Scripts to move data from your old database to your new database will be provided
• SOGo’s configuration has completely been redone. Only a few core parameters needs to be in ENV or a file. All the others one are stored in the database and are accessible through a brand new Admin interface. Except those core parameters, admin users will be able to import their old sogo.conf file on the admin interface and SOGo 6 will configure it automatically. Apart from this, all the others services stay as they are!

And SOGo 5?

As announced, only patches and bugfixes are done for the current SOGo 5. The 5.12.4 is on its way.

See you very soon!

SOGo Team