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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Consul
Consul makes it simple for services to register themselves and to discover other services via a DNS or HTTP interface. Register external services such as SaaS providers as well
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Fig
A package management tool, similar to Ivy/APT, but language agnostic, faster and works well with both executables and libraries.
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FPM
Effing Package Managers (FPM) is a single tool that can generate rpm, deb, solaris, osx (pkg) and many other packages. It supports multiple inputs (directory, gem, egg, deb, etc) and can produce multiple outputs (rpm, deb, solaris, etc). It relieves the pain out of creating various kinds of packages.
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Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
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Puppet
Puppet is a tool designed to manage the configuration of Unix-like and Microsoft Windows systems declaratively.
linux windows osx open-source config-mgmt ruby
Vagrant Cachier
A Vagrant plugin that helps you reduce the amount of coffee you drink while waiting for boxes to be provisioned by sharing a common package cache among similiar VM instances.
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Veewee
veewee is a great tool for building Virtual Machine images (aka base boxes). It automates most of the steps and allows you to easily create readymade images for VirtualBox/Vagrant, VMWare Fusion, KVM and Parallels. No longer need to shy away from building custom VM images!
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