Mastodon
Federated microblogging server.
Self-hosted Communication - Social Networks and Forums software
Social Networking and Forum software.
40 apps, ranked by GitHub stars weighted by maintenance health.
Discourse
Advanced forum / community solution based on Ruby and JS.
Flarum
Delightfully simple forums. Next-generation forum software that makes online discussion fun again.
Answer
Knowledge-based community software. You can use it to quickly build your Q&A community for product technical support, customer support, user communication, and more.
NodeBB
Forum software built for the modern web.
Lemmy
Link aggregator for the fediverse (alternative to Reddit).
Misskey
Decentralized app-like microblogging server/SNS for the Fediverse, using the ActivityPub protocol like GNU social and Mastodon.
PixelFed
Ethical photo sharing platform, powered by ActivityPub federation (alternative to Instagram).
HumHub
Flexible kit for private social networks.
remark42
Lightweight and simple comment engine, which doesn't spy on users. It can be embedded into blogs, articles or any other place where readers add comments.
Isso
Lightweight commenting server written in Python and Javascript. It aims to be a drop-in replacement for Disqus.
Redlib
Private alternative front-end to Reddit, with its origins in Libreddit.
Misago
Fully featured modern forum application that is fast, scalable and responsive.
Loomio
Collaborative decision-making tool that makes it easy for anyone to participate in decisions which affect them.
Artalk
Comment system built in Golang, providing a lightweight and highly customizable solution for adding comments to your website.
phpBB
Flat-forum bulletin board software solution that can be used to stay in touch with a group of people or can power your entire website.
Movim
Modern, federated social network based on XMPP, with a fully featured group-chat, subscriptions and microblogging.
diaspora*
Distributed social networking server.
Friendica
Social Communication Server.
Elgg
Powerful social networking engine.
OSSN
Social networking software that allows you to make a social networking website and helps your members build social relationships, with people who share similar professional or personal interests.
MyBB
Free, extensible forum software package.
Scoold
Stack Overflow in a JAR. An enterprise-ready Q&A platform with full-text search, SAML, LDAP integration and social login support.
Simple Machines Forum
Free, professional grade software package that allows you to set up your own online community within minutes.
Enigma 1/2 BBS
Modern, multi-platform BBS engine with unlimited "callers" and legacy DOS door game support.
qpixel
Q&A-based community knowledge-sharing software.
Coral
Better commenting experience from Vox Media.
Talkyard
Create a community, where your users can suggest ideas and get questions answered. And have friendly open-ended discussions and chat (Slack/StackOverflow/Discourse/Reddit/Disqus hybrid).
BuddyPress
Powerful plugin that takes your WordPress.org powered site beyond the blog with social-network features like user profiles, activity streams, user groups, and more.
Hatsu
Bridge that interacts with Fediverse on behalf of your static site.
Habitat
Platform for Local Communities.
Socialhome
Federated and decentralized profile builder and social network engine.
Akkoma
Federated microblogging server with Mastodon, GNU social, and ActivityPub compatibility.
AsmBB
Fast, SQLite-powered forum engine written in ASM.
GoToSocial
ActivityPub federated social network server implementing the Mastodon client API.
Hubzilla
Decentralized identity, privacy, publishing, sharing, cloud storage, and communications/social platform.
Iceshrimp.NET
Federated microblogging server that communicates over ActivityPub.
PieFed
Link aggregator / reddit clone for the fediverse (alternative to Reddit).
Pleroma
Federated microblogging server, Mastodon, GNU social, & ActivityPub compatible.
yarn.social
Twitter™-like Decentralised micro-logging platform. No ads, no tracking, your content, your data.