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A tool to help developers include the right vendor prefixes in their sites
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CSS Prefix

Just a precursor to this readme: this is just an idea. There are already other tools available, my plan is to add to those tools to help developers.

If this is a daft idea or doesn't have legs, say so. If there's better ways of doing something: say so.


Fork the project, and run:

npm install
node prefix.js [url]

This should output the CSS with retrofitted vendor-prefixes where they were missing. This was about 3 hours work, so if it's shoddy - I do apologise!

The Plan

Plan to build a service for developer to submit a site to that will:

  1. Plug in the missing CSS vendor prefixes
  2. Give a simple yes or no as to whether it's got all the appropriate fallback CSS properties
  3. Provide a simple API for external tools to use

Intended use

First as a red light/green light app with the ability to download updated CSS. For example:

This would return a simple page - with an indicator of whether they're not using an fallback CSS properties.

Also available for plugins to use - with the intention that a developer can use a simple plugin (for firebug, chrome extension, etc):


{ pass: true }

Or if fails:

{ pass: false, detail: [ /* here be properties that fail */ ]}

Extension could then show a bleemin' great RED FAIL icon, or happy face green unicorn riding a tick mark (or something).


  • Process the parsing of markup without blocking further requests (probably using cluster in Node)
  • Parse HTML, CSS, @imports, etc to find all CSS embedded in document (note: I've done this before)
  • Parse CSS to process properties used (either's Zakas' CSS lint parser or Lea Verou's -prefix-free might have this already (no go on Lea's code - spoke to her, and it doesn't include a parser))
  • Have a converter library to go from CSS property to all fallbacks required. Question maybe this could also use a minimum browser support flag - such as supporting IE8 would require filters for opacity...maybe not worth it?
  • Site design - something clear, simple and to the point.
  • Not sure about this - but what about a wall of shame???!

Tool integration

Ideas how to get this baked in to developer's work flow:

  1. TextMate commands
  2. Other editor commands (I'm not a TextMate user - I know, weird, right!?)
  3. Browser extensions (as mentioned above)
  4. Others?


Server side is in Node, using Express to get up and running quickly. It also means that I can pull in the CSS parsers without having to do (too much) conversion.


I'm looking for help in the following areas:

  • UX for web site
  • Design for web site
  • CSS, HTML & JavaScript for web site
  • Testing (once the server is complete)
  • Third party tools (extensions, proof of ideas)
  • Support on server-side JS (though I'll get as far as possibly in as short amount of time as possible first though)
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