Carbon-Forum - A high performance open-source forum software written in PHP

•    PHP

A high performance open-source forum software written in PHP.

Spectrum - Simple, powerful online communities

•    Javascript

Spectrum aims to be the best platform to build any kind of community online by combining the best of web 2.0 forums and real-time chat apps. With best-in-class moderation tooling, a single platform for all your communities, threaded conversations by default, community health monitoring (and much more to come), we think that we will be able to help more people start and grow the best online communities.

Forem - For empowering community

•    Ruby

Forem is open source software for building communities. Communities for your peers, customers, fanbases, families, friends, and any other time and space where people need to come together to be part of a collective. dev.to (or just DEV) is hosted by Forem. It is a community of software developers who write articles, take part in discussions, and build their professional profiles.

Helpy - Modern Mobile-First Helpdesk Application Built in Ruby

•    Ruby

A modern, open-source and multi-lingual helpdesk, including email tickets, knowledgebase and forums. All your customer communications in one place, accessible from anywhere. Its features include multi-lingual knowledgebase, community discussions and private tickets integrated with email and lot more.

Vanilla forums - customizable discussion forum with mobile support

•    PHP

Vanilla is a powerful community publishing platform, and it comes with a great set of features. It has add-ons to embed your vanilla forums in to any of the site with single line of code. User will be allowed to login with their Facebook, Twitter, Google and OpenID account.

mvcforum - MVCForum is a fully featured responsive and themeable ASP

•    Javascript

MVCForum is a fully featured and themeable enterprise level ASP.NET MVC 5 discussion board/forum. The software has features similar to that seen on StackOverFlow plus LOTS more (See list below). Along with MVC it’s built using Unity & Entity Framework 6 code first and is super easy to extend and add your own features.

Misago - Full featured forum application standing on shoulders of Django

•    Python

Misago aims to be complete, featured and modern forum solution that has no fear to say 'NO' to common and outdated opinions about how forum software should be made and what it should do.

Symphony - A modern community (forum/BBS/SNS/blog) platform written in Java

•    Java

Symphony is a modern community platform. It implements a content oriented discussion forum. It includes a social network for users to share, make friends, and play games. It has the ability to aggregate independent bloggers, to build and share quality resources.

Aether - peer-to-peer network of independent, self-moderated communities

•    Go

Aether is a peer-to-peer network of independent, self-moderated communities. It is a Open source, self-governing communities with auditable moderation and mod elections. Aether is private by default, so that you can choose to be fully private, or fully public yourself. Most people use pseudonyms, though you can use your real name, or company.

Chatter - Simple Laravel Forum Package

•    PHP

The Chatter package allows you to easily create a Laravel forum from any existing or new Laravel application.

frontend-playbook - The Frontend Playbook

This repo contains The Frontend Playbook. It details how we run software development and how we make web and mobile products together. It's filled with things we've learned based on our own experience and study of others' experiences. The main motivator for this playbook is not to document a list of guidelines, but rather to create an opportunity to collaborate on them, and to gain consensus.

goyoubbs - goyoubbs is an open source web forum built on Golang, fasthttp and leveldb.

•    Go

goyoubbs is an open source web forum built on Golang, fasthttp and leveldb. Download source code and build.

Active Forums for DotNetNuke CMS

•    DotNet

Active Forums for DotNetNuke CMS

Comments App - A real-time, markdown-enabled comment engine powered by leveldb with oauth support

•    Javascript

A real-time comment engine with support for anonymous or authenticated posts.

NoNonsenseForum - A free, open source, PHP-based simple discussion forum

•    PHP

A free, open source, PHP-based simple discussion forum. It favours removing barriers to conversation rather than massaging egos. Download Here: https://github.com/Kroc/NoNonsenseForum/archive/master.zip

yii2-podium - Yii 2 forum module project

•    PHP

This extension allows you to add forum to your app.Follow instructions at Podium wiki.

Elkarte - ElkArte Forum. A free, open source, PHP-based discussion forum.

•    PHP

This is the ElkArte repository.ElkArte is a modern, free, powerful community building forum software. It is completely free and licensed with an open source BSD 3-clause license.

refire-forum - Serverless discussion forum built with React, Redux and Firebase

•    Javascript

Serverless discussion forum built with React, Redux and Firebase using refire and refire-app.Base UI components are from excellent Elemental UI.

converse - Experimental discussion forum built with Maki.

•    Javascript

A prototype discussion forum built on Maki.

flowchat - A live updating, threaded discussion platform with range voting.

•    Java

FlowChat is an open-source, self-hostable, live-updating discussion platform, featuring communities, discussions with threaded conversations, and voting.It can act as an alternative to forums, as a private team communication platform(like slack), a content creation platform(like reddit), or a voting/polling platform like referendum.