Minify is a PHP5 app that helps you follow several of Yahoo!'s Rules for High Performance Web Sites.

It combines multiple CSS or Javascript files, removes unnecessary whitespace and comments, and serves them with gzip encoding and optimal client-side cache headers.

Before
After

The stats above are from a brief walkthrough which shows how easy it is to set up Minify on an existing site. It eliminated 5 HTTP requests and reduced JS/CSS bandwidth by 70%.

The design is somewhat similar to Yahoo's Combo Handler Service, except that Minify can combine any local JS/CSS files you need for your page.

Minify integrated into other Projects/Plugins

• WordPress: WP-Minify
• WordPress: W3 Total Cache
• Zend Framework: View helpers for links/scripts
• Yii: minscript Extension

News

2011-07-05 Minify's active code branch has moved. Now accepting pull requests!

2010-07-08 2.1.4 beta out. Lots of new stuff.

2010-05-24 Minify integrated into Moodle 2.0

2009-09-23 New CookBook (improving performance and more configuration) and other new wiki pages.

2009-06-30 Minify 2.1.3 released, fixing some CSS and HTTP bugs (notably improving caching in webkit browsers). See History for more details.

Features

• Combines and minifies multiple CSS or JavaScript files into a single download
• Uses an enhanced port of Douglas Crockford's JSMin library and custom classes to minify CSS and HTML
• Caches server-side (files/apc/memcache) to avoid doing unnecessary work
• Responds with an HTTP 304 (Not Modified) response when the browser has an up-to-date cache copy
• Most modules are lazy-loaded as needed (304 responses use minimal code)
• Automatically rewrites relative URIs in combined CSS files to point to valid locations
• With caching enabled, Minify is capable of handling hundreds of requests per second on a moderately powerful server.
• Content-Encoding: gzip, based on request headers. Caching allows it so serve gzipped files faster than Apache's mod_deflate option!
• Test cases for most components
• Easy integration of 3rd-party minifiers
• Separate utility classes for HTTP encoding and cache control

Requirements

• PHP 5.1.6.
• The commonly installed zlib extension is recommended for HTTP encoding functionality.
• Version 1.0.1 required PHP 5.2.1+.

Installation

See the UserGuide.

Support List

PHP5 Component Classes

Minify is based on several PHP5 classes that may be useful in other projects (all BSD licensed).

Warnings

• Minify is designed for efficiency, but, for very high traffic sites, Minify may serve files slower than your HTTPd due to the CGI overhead of PHP. See the FAQ and CookBook for more info.
• If you combine a lot of CSS, watch out for IE's 4096 selectors-per-file limit. This bug has been verified in IE versions 6 through 8 (so far).

Problem Domain

Pages that refer to multiple CSS or JavaScript files often suffer from slower page loads, due to the browser requesting each file individually. Many browsers also are limited to a few simultaneous requests per domain. The wait for a series of requests and the transfer of unoptimized files can dramatically reduce the client-side performance of your site.

Here are some of Yahoo!'s best practices that are addressed by the use of Minify.

• Make Fewer HTTP Requests
• Add an Expires or a Cache-Control Header
• Gzip Components
• Minify JavaScript and CSS
• Configure ETags
• Keep Components under 25K

Acknowledgments

Minify was inspired by jscsscomp by Maxim Martynyuk and by the article 'Supercharged JavaScript' by Patrick Hunlock.

The JSMin library used for JavaScript minification was originally written by Douglas Crockford and was ported to PHP by Ryan Grove specifically for use in Minify.

You may contact Steve Clay (steve@mrclay.org) or Ryan (ryan@wonko.com) if you're interested in joining the project.