Free Software for JavaScript
Snowpack
Snowpack enables frontend developers to enjoy a lightning-fast development experience. It's modern build tool that replaces heavier, more complex bundlers like Webpack or Parcel in your development workflow. Snowpack leverages JavaScript's native module system to increase performance and never builds the same file twice. Allowing you to enjoy a near instant hot module reload and refresh no matter how big your project grows. Snowpack supports JSX, TypeScript, React, Preact, CSS Modules and much more, while also provding an extensive plugin catalog with support for almost any technology in the JavaScript eco-system.
SvelteKit
SvelteKit is a free and open-source framework used to create SSR, Static and Serverless web applications with Svelte. SvelteKit aims to replace Sapper and in the process unify the eco-system and have a single way to start building apps with Svelte. This will simplify on-boarding, and reduce maintenance and support burden for the core developers. SvelteKit fully embraces the serverless paradigm and has support for all the major serverless providers. Under the hood, SvelteKit uses Snowpack in development and compiles and hot reloads your code near instantly, making it an extremely pleasant developer experience.
Deployd
Deployd is a free and open-source web development tool for Node.js that makes building APIs simple by providing important ready-made functionality out-of-the-box. Features provided by Deployd can demands of complex applications and can be further customized with JavaScript Events.
Svelte
Svelte introduces a radical new approach to building user interfaces with JavaScript. It is a compile-based component framework that builds efficient code that updates the DOM. Where most traditional frontend JavaScript framework does most of their work in the browser, Svelte includes that work in the compilation process when you build your app. This creates a smaller app which ultimately leads to faster load times and a better experience for the end-user.
TiddlyWiki
TiddlyWiki is a personal wiki and a non-linear notebook that provides an interactive way to manipulate and structure data for web consumption. The free and open source application is written as an SPA (Single Page Application) with JavaScript by Jermolene. TiddlyWiki is designed from the ground up to easy to customize and re-shape depending on your use-case, while also providing tools that can be used to split up and reuse content.
Vue.js
Vue.js is a free and open-source intuitive and composable MVVM framework for building interactive UIs with JavaScript. The library was first created and released by Evan You back in 2014, and saw a meteoric rise in the open-souce community. Possibly due to the accessible nature of the project and the library itself. With Vue.js you can get started by simply importing the script via CDN, and start building. Today, Vue.js is used in a multitude of web applications and powers interactive interfaces for people to enjoy across the globe.
TypeScript
TypeScript is a free and open-source programming language created by Microsoft. The language is a strict syntactical superset of JavaScript and redefines the way developer writes JavaScript-based web applications and software by adding optional static typing in the mix. TypeScript is designed specifically for development of large-scale applications with a need to transcompile into JavaScript.
Next.js
Next.js is a free an open-source JavaScript framework for building production grade React web applications that scale. World's leading companies use the framework to buil both static and dynamic websites and web applications.
Pika.dev
Pika.dev is a front-end package manager that aims to make the web 90% faster by using ES module syntax (ESM). With Pika.dev youi can find modern, web-ready packages on npm and deliver them as smaller JavaScript bundles.