Berkshelf
A cookbook source structure manager for Chef, similar to Bundler for Ruby. Each Chef cookbook can be structured as an individual entity and can be pulled into your main Chef workflows.
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Supervisor
Supervisor can manage application processes. It can start and stop a group of processes, restart processes if any of them terminate (keep-alive), start multiple instances of the same process (process pooling), automatically manage PID files, and much more! Very useful if you need to manage multiple processes for your application.
linux osx open-source process-mgmt python