Open Source Software for Self-Hosted
Dokku
Dokku is a free and open-source project that helps you build and manage the lifecycle of applications. With Dokku developers can setup their own PaaS (Platform-as-a-Service) in a matter of minutes. Dokku provides extra plugins which can be used to manage database, and tools needed for your application. If you need to server your application over HTTPS, Dokku got you covered as well, with the help of Let's Encrypts free TLS certificates.
RedwoodJS
RedwoodJS is a free and open-source fullstack JavaScript framework for the JAM stack. The framework is highly opinionated and utilize the best practises for building fullstack web applications with React, GraphQL, Prisma and relational databases. Redwood is designed to be deployable completely to the Edge via CDNs and serverless functions distributed everywhere. The structure and tools provided by RedwoodJS let's you get up and running quickly, so that you can see your application go from idea to reality.
Elgg
Elgg is an award-winning open source social networking engine that provides a robust framework on which to build all kinds of social environments, from a campus wide social network for your university, school or college or an internal collaborative platform for your organization through to a brand-building communications tool for your company and its clients.
Diaspora
Diaspora is a privacy-aware, distributed, open source social network developed by the Diaspora Foundation. The social network is built up of distributed pods, that can be self-hosted by anyone. However, to join the Dispora, you can simply chose an already hosted pod on the network. Members can share and discuss content with others, and label content with hashtags, allowing them to easily follow certain topics that they are interested in. Diaspora also supports @mentions and re-shares of posts, features which all adds up to an intricate communication and sharing system, distributed across the globe.
Formik
Formik is a free and open-source library for building forms with React. The library improves on the otherwise verbose process of creating forms in React by minimizing the need for repetition and eliminating the cumbersome process of keeping track of values, errors, visited fields and orchestrating validation and error handling.
Saaze
An all-inclusive, flat-file CMS for simple and fast content management. While regular content management systems like WordPress are great, the complexity of running sush a site can easily become a burden. They also have a larger attack vector due to popularity and the fact that they utilize a relation database mangement system to serve and manage the content. Saaze is fundamentally different, the flat-file architecture of Saaze makes hosting content for the web easy to manage, secure and fast to load.
Nextcloud
With Nextcloud, users can host their own secure cloud solution for file storage, collaboration and communication for enterprise or personal purposes. Nextcloud gives you full control over your own data and where and how you host it. The software can be hosted on-premise or on any VPS or cloud instance provided by third-party web hosts. If you value privacy and security, Nextcloud might be the right choice for you. Nextcloud is both free and open source and developed in an open, transparent and trustworthy manner.
VuePress
VuePress is a free and open-source Vue-powered Static Site Generator or SSG for short. VuePress utilize the power and simplicity of Markdown files to generate content. Which allow the creator to focus on their writing, instead of formatting HTML. With VuePress, developers can harnes the power of Vue components in a simplified build step using Vue + webpack.
Restyaboard
Restyaboard is an open source kanban board part of the Restya platform. Restyaboard can be extended using a simple Greasemonkey like approach offering offers countless way to expand--widgets, user scripts and user styles. It also provides integration and workflow automation using over 500 apps and third-party services via Zapier.
Apache HAWQ
Apache HAWQ is an open-source elastic query engine, MPP and analytical database for enterprises. Apache HAWQ combines exceptional MPP-based analytics performance, robust ANSI SQL compliance, Hadoop ecosystem integration and manageability, and flexible data-store format support.