Robert Mosolgo

Finding a Browser-Ready File for Sprockets

I like using Sprockets, but sometimes it’s hard to find a file to include in the asset pipeline. Here are some methods I use to find browser-ready JavaScript files.

There are a few good options for getting browser-ready files for JavaScript libraries:

  • Download a file from the project’s website
  • Download a file from the project’s source code repository
  • Download a file from a CDN (npmcdn is great for cases where files are only “compiled” for releases)
  • Build the file yourself, following the project’s documentation

Don’t get a minified version. Sprockets will minify it for us later. In the meantime, the unminified version will help us during development.

From a Website

This is the good ol’ way of getting JavaScript files. Because we still use browsers, you can still download these files.

Here are some examples:

From the Repo

Many projects maintain a browser build in the project’s source. You may have to poke around a bit, but likely places are the project’s root folder, the dist/ folder, or the build/ folder.

As you explore the repo, remember to examine a stable ref, such as a release or a stable branch.

Here are some examples:

From a CDN

CDNJS hosts browser-ready files for many libraries.

Sometimes, an author only compiles browser-ready files for releases to NPM. You can get these files from npmcdn.

Since npmcdn is serving NodeJS projects, employ a similar technique to searching the project repo for a file:

  • Check the “main” file
  • Check the “dist” or “build” directories

Build it from Source

If a pre-built, browser-ready file is not available, you may have to build it yourself! The project’s readme will contain instructions to do so. If it doesn’t … you may want to reconsider adding this dependency! (Even if it’s well-maintained, it’s not a good match for this asset bundling approach.)


Hopefully these will work well for you!

You may have to learn a bit of RequireJS, jspm, Grunt, Browserify, Gulp, Webpack or Rollup along the way. (Ok, probably not Rollup, sadly.) But at least you don’t have to use them day-in and day-out!