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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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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