Chef
Configuration management tool which uses a pure-Ruby, domain-specific language (DSL) for writing system configuration recipes. Supports Linux, UNIX, Windows, and AIX as first-class citizens for management.
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ConDep
ConDep is a open source infrastructure configuration and deployment DSL (Domain Specific Language) specifically targeted to (but not limited to) the Windows Server platform. If your familiar with tools like Chef and Puppet, ConDep does very much the same, but with native support for Windows.
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Djangy
An open source cloud hosting service for Python/Django web applications. Its like an open source Heroku for python/django
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FastForward
Flexible operating-system event and metric forwarding agent. Receives input and forwards output using plugins.
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Fog
The Ruby Cloud API library. Provides a Ruby API for interacting and managing many cloud providers, such as spinning up new instances, terminating old ones, attaching storage, etc. Currently supports more than 20 providers, including EC2, Rackspace, Brightbox, etc.
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jclouds
A Java Library for controlling cloud resources, with various plugins for many popular cloud providers.
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KairosDB
KairosDB is a fast distributed scalable time series database written on top of Cassandra. RESTful JSON-based query/results. Includes flot-based visualization.
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Apache Libcloud
Python library for interacting with many of the popular cloud service providers using a unified API.
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PowerShell Desired State Configuration
DSC is a new management platform in Windows PowerShell that enables deploying and managing configuration data for software services and managing the environment in which these services run.
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Pulumi
Create, deploy, and manage Cloud Native infrastructure, as real code. A single toolset for infrastructure, managed services, containers, and serverless environments on any cloud infrastructure. You get all the benefits of real programming languages; IDEs, abstractions and reuse thanks to functions, classes, and packages, debugging, testability, and more
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Puppet
Puppet is a tool designed to manage the configuration of Unix-like and Microsoft Windows systems declaratively.
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SaltStack
Salt is a powerful and different approach to infrastructure management, by focusing on high speed communications between large number of systems, and can perform orchestration, remote code execution and much more.
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