BOSH is a project that unifies release engineering, deployment, and lifecycle management of small and large-scale cloud software.
BOSH can provision and deploy software over hundreds of VMs.
It also performs monitoring, failure recovery, and software updates with zero-to-minimal downtime.
While BOSH was developed to deploy Cloud Foundry PaaS, it can also be used to deploy almost any other software (Hadoop, for instance).
BOSH is particularly well-suited for large distributed systems.
In addition BOSH supports multiple Infrastructure as a Service (IaaS) providers like VMware vSphere, vCloud Director, Amazon Web Services EC2, and OpenStack.
There is a Cloud Provider Interface (CPI) that enables users to extend BOSH to support additional IaaS providers such as Google Compute Engine and Apache CloudStack.