Free Software for JavaScript
Hexo
A fast, simple & powerful blog framework and static site generator powered by Node.js. With Hexo, you can quicly build static websites and blogs that generates at an increaible speed. Hexo generates hundreds of files per seconds and quickly builds and push your website to deployment, with a single command. You can have your site up and running in minutes on well known hosts and platforms like GitHub Pages, Heroku, Digital Ocean and other platforms. The framework support all features of GitHub Flavored Markdown and most Octopress plugins by default. Hexo is released free and open-source under the MIT License.
Apache Cordova
Apache Cordova is a mobile application development framework that enables developers to build hybrid web applications for mobile devices using CSS3, HTML5, and JavaScript. Instead of relying on platform-specific APIs, Apache Cordova allows you to build your application once, and ship anywhere.
KeystoneJS
KeystoneJS is an open source JavaScript & Node.js framework that make build database-driven websites and web applications. Under the hood, KeystoneJS uses the express.js web server framework, and a MongoDB database via the mongoose object modelling framework.
Total.js
Total.js is a free and open-source framework for Node.js platform written in pure JavaScript. The framework share many similarities with other giants like PHP's Laravel, Python's Django and ASP.NET MVC. Developers use Total.js to build modern web, desktop and IoT applications.
Koa
Koa is a free and open-source, expressive HTTP middleware framework for Node.js. Koa provides a great developer experience that makes writing web applications and APIs more enjoyable. Koa's middleware stack flows in a stack-like manner, allowing you to perform actions downstream then filter and manipulate the response upstream. Only methods that are common to nearly all HTTP servers are integrated directly into Koa's small codebase. This includes things like content negotiation, normalization of node inconsistencies, redirection, and a few others.
Gatsby
Gatsby is a free and open source framework and site generator that helps developers to build blazing fast websites and apps. The framework is based on React and include a plugin ecosystem that can be used to extend the capabilities of Gatsby. With Gatsby you can pull data from headless CMSs, SaaS services, APIs, databases, even your file system with the help of GraphQL. If you are looking to build a fast website that scales with time, Gatsby might your best pick.
Electron
Electron is a framework that lets you build cross-platform desktop apps with JavaScript, HTML, and CSS. It takes care of the hard parts of building native software, so that you can focus on the core purpose of your application.
React Hook Form
React Hook Form is a tiny form library without any dependencies. With the library it's simple to create React-based, performant, flexible and extensible forms with proper validation. React Hook Form is built with performance and DX in mind and embraces native form validation with simple integration to various UI libraries. Allowing developers to crete tiny size forms without dependancy, that follows HTML standards for validation. React Hook Form also provides resolvers support for third-party validation libraries like Yup, Zod, Superstruct, Joi or your custom sulotions.
Wiki.js
With Wiki.js you can run a blazing fast Wiki built with performance in mind. Wiki.js is an extensible, free and open source Wiki software written in JavaScript. Wiki.js brings a modern approach to documentation and Wiki writing, it provides a simple to use WYSIWYG editor, a Markdown editor and a visual builder to please all types of workflows. All content moderation is also tracked on a Wiki.js-powered site, which means that you can an revert to a previous state or recover a deleted page at any time and get a broad overview of content evolution. Allowing you to visually compare two versions of the same page to see exactly what changed. Wiki.js runs on virtually any platform and is compatible with either PostgreSQL, MySQL, MariaDB, MS SQL Server or SQLite.
Webpack
Webpack is an open-source module bundler for JavaScript. Its main purpose is to bundle JavaScript files for usage in a browser, yet it is also capable of transforming, bundling, or packaging just about any resource or asset. It can transform front-end assets like HTML, CSS, and images where corresponding loaders ar included and takes modules with dependencies and generates static assets representing those modules.