I discovered Dotdeb a few months ago and decided to make a quick documentation to install the repository. But before, here is the official explaination of what is the repository made for :
Dotdeb is a repository containing packages to turn your Debian boxes into powerful, stable and up-to-date LAMP servers :
Nginx PHP 5.4 and 5.3, useful PHP extensions : APC, imagick, Pinba, xcache, Xdebug, XHprof… MySQL 5.
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