Free Software for Self-Hosted
Rocket.Chat
A free, unlimited and open-source chat software. Rocket.Chat have set out to be a replacement for email, HipChat & Slack and is provided as Software-as-a-Service (SaaS) or a self-hosted community edition. Rocket.Chat is feature packed and can be used for video conferencing, file sharing, voice messages and more. The software integrates with third-party services like GitHub, GitLab, JIRA, and Confluence and provides an API that can be used for authentication and integration across these services.
BuddyCloud
Buddycloud is an open source project that helps developers add chat, video and social features to their app without being locked into a proprietary solution. With BuddyCloud it's easy to build communities that facilitates rich communication. The open-source toolset is written in Java and is designed to scale well and save you your team time, when building an online community.
Yii Framework
Yii is a fast, secure, and efficient framework written in PHP. The framework is flexible yet pragmatic and works right out of the box with resanable defaults. With the Yii framework you can write more code in less time with simple with a powerful APIs and that include terminal commands for code generation for quick skaffolding. Yii is released as free and open source software under the liberal MIT License.
Symfony
Symfony is a reusable set of standalone, decoupled and cohesive PHP components that solve common web development problems. Instead of using these low-level components, you can use the ready-to-be-used Symfony full-stack web framework, which is based on these components, or you can create your very own framework. Symfony is released as a free and open source framework under the MIT License.
IPFS
The InterPlanetary File System or IPFS for short is a distributed hypermedia protocol designed to be the new permanent web. IPFS uses peer-to-peer to distribute the network across machines and the globe. IPFS combines decentralized technologies like Git, BitTorrent, Kademlia and SFS to build what they think could be the new internet, or a subsystem of it.
Sails.js
Sails.js is a JavaScript framework that makes it easy to build custom, enterprise-grade Node.js apps. It is designed to resemble the MVC architecture from frameworks like Ruby on Rails, but with support for the more modern, data-oriented style of web app development. The framework is suited for building applications with realtime features.
Wekan
Wekan is a free and open soure, web-based, kanban tool that can be self-hosted. With Wekan you can maintain personal todo lists, keep an itinerary for you next trip with your friends or collaborate with your team on large scale projects. The Kanban experience provided by Wekan makes it super easy to get a broad overview of your project and how you and your team can move it forward.
Scrapy
Scrapy is a fast and powerful web scraping library written in Python. The framework makes it easy to crawl and extract structured data from the web services. Scrapy can be used for a wide range of purposes, ranging from data mining to service monitoring. Scrapy is maintained by Zyte and is released as free and open source software.
SparkleShare
SparkleShare is a free and open-source cloud storage and file synchronization software. By default SparkleShare uses Git as a storage backend and creates a special folder on your computer that you can add remotely hosted folders (directories). Projects in this folder will automatically stay synced with the host and its peers. When someone add, remove or edit files within a project, syncronization happens across peers. SparkleShare can be used with hosted services such as GitHub, but can also be hosted on your own server for more control.