Boxstarter
Repeatable, reboot resilient windows environment installations made easy using Chocolatey packages. When its time to repave either bare metal or virtualized instances, locally or on a remote machine, Boxstarter can automate both trivial and highly complex installations. Compatible with all Windows versions from Windows 7/2008 R2 forward.
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Chocolatey
Chocolatey is like apt-get for Windows. It can install packages and dependencies over the command line.
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FAI
Fully Automatic Installation (FAI) is a tool for mass unattended deployment of Linux. You can take one or more virgin PCs, turn on the power, and after a few minutes, the systems are installed and completely configured.
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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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Phabricator
Phabricator is an open source collection of development and code management, including code reviews and audits, browsing repositories, tracking bugs, etc
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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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