7 self-hosted Microsoft Yammer alternatives

Apache Answer is a modern open-source Q&A platform for teams to build knowledge bases, forums, and help centers.

15.6k stars1.3k forksApache-2.0last commit 17 Jul 2026Actively maintained

NodeBB is a modern forum platform with real-time discussions, built-in chat, SSO options, plugins, and flexible theming, backed by Redis, MongoDB, or PostgreSQL.

15.2k stars3k forksGPL-3.0last commit 27 Jul 2026Actively maintained

Open-source intranet and enterprise social network for communication, collaboration, and knowledge sharing with a modular, extensible design.

6.7k stars1.7k forkslast commit 22 Jul 2026Actively maintained

Loomio is a collaborative decision-making tool for group discussions, proposals, and polls, helping teams make transparent decisions asynchronously with a clear record.

2.6k stars703 forksAGPL-3.0last commit 27 Jul 2026Actively maintained

Elgg is a modular open source platform for building social networks and collaborative communities with plugin-based extensions.

1.7k stars667 forkslast commit 10 Jul 2026Actively maintained

MyBB is a PHP-based, open-source forum platform with plugins, themes, moderation tools, private messaging and multi-database support.

1.2k stars439 forksLGPL-3.0last commit 27 Jul 2026Actively maintained

Mbin is a federated content aggregator offering voting, discussion and microblogging via ActivityPub. A community-focused fork of kbin, built with PHP and Symfony.

425 stars32 forksAGPL-3.0last commit 28 Jul 2026Actively maintained