This document discusses DevCloud, a virtual appliance that provides a working CloudStack environment for development and testing purposes. It can be used to try CloudStack in an isolated sandbox, develop CloudStack locally and deploy new versions to DevCloud, or develop and run CloudStack locally using DevCloud as Xen hosts. The steps to install and configure DevCloud in VirtualBox are provided, which include downloading the DevCloud virtual appliance, importing it into VirtualBox, starting the VM, and checking out and deploying the latest CloudStack code. Ways to contribute to the CloudStack community are also listed, such as participating in discussions, reporting bugs, reviewing code, helping with documentation, and contributing code fixes and features.