The developers of Ruby on Rails have come up with yet another small but important innovation in the world of Web applications. Way back in release 0.14, they added the ability to freeze rails, which copies all of the system-wide Ruby libraries you might depend on into a directory in the application so that if the packages on the system get upgraded, your applications won’t break. This makes for fatter applications, but vastly reduces the risk that anyone will break your stuff.
In the Java world, developers have been including JAR files in their web application archives for ages. When I write a Java application, every library other than the ones in the Java class library I use is packaged with the application. Now I can easily do the same thing with Rails applications. Someone needs to add write some scripts to bring this functionality to Perl and PHP. applications. I’d love it if it were this easy to bring along your CPAN or PEAR libraries with your application code.