### What is Snowpack?
**Snowpack is a modern, lightweight toolchain for web application development.** Traditional dev bundlers like webpack or Parcel need to rebuild & rebundle entire chunks of your application every time you save a single file. This introduces lag between changing a file and seeing those changes reflected in the browser, sometimes as slow as several seconds.
Snowpack solves this problem by serving your application **unbundled in development.** Any time you change a file, Snowpack never rebuilds more than a single file. There's no bundling to speak of, just a few milliseconds of single-file rebuilding and then an instant update in the browser via HMR. We call this new approach **O(1) Build Tooling.** You can read more about it in our [Snowpack 2.0 Release Post.](https://www.snowpack.dev/posts/2020-05-26-snowpack-2-0-release/)
When you're ready to deploy your web application to users, you can add back a traditional bundler like Webpack or Parcel. With Snowpack you get bundled & optimized production performance without sacrificing dev speed by adding an unnecessary bundler,
### Key Features
- A dev environment that starts up in **50ms or less.**
- Changes are reflected [instantly in the browser.](https://www.snowpack.dev/posts/2020-05-26-snowpack-2-0-release/#hot-module-replacement)
- Integrates your favorite bundler for [production-optimized builds.](https://www.snowpack.dev/posts/2020-05-26-snowpack-2-0-release/#snowpack-build)
- Out-of-the-box support for [TypeScript, JSX, CSS Modules and more.](https://www.snowpack.dev/posts/2020-05-26-snowpack-2-0-release/#features)
- Connect your favorite tools with custom [build scripts](https://www.snowpack.dev/posts/2020-05-26-snowpack-2-0-release/#build-scripts) & [third-party plugins.](https://www.snowpack.dev/posts/2020-05-26-snowpack-2-0-release/#build-plugins)
**💁 More info at the official [Snowpack website ➞](https://snowpack.dev)**