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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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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Docker
Docker uses LXC to create and manage native, sandboxed virtual containers. LXC containers acts like a separate OSes, can install their own packages without affecting anything else, and overall have almost the same flexibility of VMs but without any of the virtualization overhead! Docker adds a ton of features, like an elegant configuration file that automates many things (like port forwarding, disk/directory mounting, networking, etc), a way to create and share readymade images that can be distributed as appliances, etc.
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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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LXD
LXD is a next generation system container manager. It offers a user experience similar to virtual machines but using Linux containers instead. It's image based with pre-made images available for a wide number of Linux distributions and is built around a very powerful, yet pretty simple, REST API.
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Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
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Weave
Weave creates a virtual network that connects Docker containers deployed across multiple hosts. Services provided by application containers on the weave network can be made accessible to the outside world, regardless of where those containers are running. Similarly, existing internal systems can be exposed to application containers irrespective of their location.
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