Instrumental
Instrumental is a real-time, high-scale application and server monitoring tool with intelligent alerts, a powerful query language, and free development accounts.
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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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SaltStack
Salt is a powerful and different approach to infrastructure management, by focusing on high speed communications between large number of systems, and can perform orchestration, remote code execution and much more.
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