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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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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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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Apache Libcloud
Python library for interacting with many of the popular cloud service providers using a unified API.
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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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Supervisor
Supervisor can manage application processes. It can start and stop a group of processes, restart processes if any of them terminate (keep-alive), start multiple instances of the same process (process pooling), automatically manage PID files, and much more! Very useful if you need to manage multiple processes for your application.
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Vaurien
A Chaos Monkey for TCP, it randomly disconnects or stalls TCP connections in your application to test application tolerance and high availability. Makes sure you correctly handle these unexpected events
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