• PHP 5.1 or higher (5.2 or higher recommended)
  • With SSL support
• MySQL 3.2 or higher (4.1 or higher recommended)
• Apache web server with mod_php
• Any *nix-like system. Windows works for testing and tryout, but it is not recommended for production use.
• PHP SOAP extension (for PayPal Website Payments Pro)
• Either PHP CUrl extension or PHP SSL-enabled streams

Optional, but recommended

• GD and the GD PHP extension
• Apache mod_rewrite