Sky is a Python (3.4) library and command-line tool for rapid deployment of cloud infrastructures. It supports DevOps by defining infrastructure as code and orchestrating resource creation and termination.

The command line tool is an application-level interface to Amazon Web Services that leverages the boto library.

Typical use involves the creation of a Python module with one or more functions, then executing them via the sky command-line tool. Below is an example "skyfile" that places an Amazon EC2 instance (a server) within a Virtual Private Cloud (a private network).

from sky.api import create_network, create_instances

@permanent
@infrastructure
def network():
    virtual_network = create_network(network_class='b',
                                     internet_connected=True)
    public_subnets = create_subnets(virtual_network,
                                    zones='us-east-1b',
                                    byte_aligned=True,
                                    public=True)

@ephemeral
@infrastructure(requires=['network'])
def application():
    instances = create_instances(ready.network.virtual_network,
                                 ready.network.public_subnets,
                                 internet_addressable=True,
                                 role='application')

Note that the infrastructure decorator denotes a function as a cloud resource, to be created by the sky command-line tool. This decorator takes an optional requires argument, where requisite infrastructure can be listed.

A special ready Object allows functions to reference infrastructure created earlier in deployment.

Once an infrastructure is defined, it may be deployed to AWS, like so:

$ sky deploy

In addition to use via the sky tool, Sky's components may be imported into other Python code, providing a Pythonic interface to cloud services, such as Amazon Web Serveices.