CoreOS
CoreOS is an extremely lightweight base OS for Docker. It installs just a kernel, systemd and docker, and then you use Docker to pull in any service that you want. Can be used as a base OS when running your own PaaS with Docker, or other kind of deployments.
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Fabric8
fabric8 is an end to end development platform spanning ideation to production for the creation of cloud native applications and microservices
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Netboot.xyz
Netboot.xyz is a preconfigured iPXE bootloader that completely eliminates the need for large ISO files for a vast range of operating systems.
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r10k
r10k provides a general purpose toolset for deploying Puppet environments and modules. It implements the Puppetfile format and provides a native implementation of Puppet dynamic environments.
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Review Board
Review Board is a feature packed code review tool for multiple SCM systems (like git, bzr, cvs, subversion, etc).
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RocketGit
Free (as in speech and as in beer) software (AGPLv3+) for hosting Git® projects, both public and private.
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