Ansible
A versatile orchestration engine that can automate systems and apps. Instead of a custom scripting language or code, it is very simple and shell based. It is also agent-less, so you can just start using it right away and get things done
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Assimilation System Management Suite
The Assimilation Suite discovers systems, services, network connections, configuration and dependencies, IP and MAC addresses. This all goes into a continually updated graph-based configuration management database (CMDB). This is then compared and scored against best practices, services and servers are monitored - all with near-zero configuration - in a way that scales to hundreds of thousands of servers. It also provides visualization tools, APIs for sending alerts to humans and other systems, and a variety of canned reports (queries) to aid in securing and managing systems, hooking into ChatOps, and creating plans for triaging your security issues
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bugsnag
Monitor everything you're building.
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Buildbot
Buildbot is an open-source framework for automating software build, test, and release processes. It differs from other CI tools in that it is more of a betteries included Framework, rather than a tool, and can hence be grown to meet your own needs. One of the reasons it is used in many high profile open source projects like Chromium, Firefox, Webkit, Python, etc.
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