ConfigCat
ConfigCat is a feature flags as a service. It gives you a web based dashboard to manage your feature flags + SDKs to integrate those feature flags into your applications. ConfigCat enables you to use the same feature flags in your mobile apps, websites and server-side applications. It offers all features for free. You get an enterprise-ready SLA with the pricing plans.
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Hubot
Hubot is a chat bot that can be configured to do a variety of tasks. Apart from usual CI stuff like deploying, it can be interestingly configured to do different workflows like posting images, translating languages and integrating with Google Maps, and being a bot, it can be configured to ask questions like what is the current deployed version, etc.
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Pallet
A tool to provision and maintain servers across various cloud platforms as well as virtual machine platforms, without any dependencies. Provides cloud and operating system independence.
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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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Rex
A agent-less server orchestration tool built on Perl
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