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A Trigger is a Continua feature that waits for certain events to occur, when they occur the Configuration the trigger is assigned to is executed. A trigger can be setup to execute the Configuration when a check in is made to a specified repository or at a certain period in time.
Under the hood
Unlike some other CI servers like FinalBuilder Server and Hudson, Continua manages the 'getting' of your source code. Primarily this is so that it is quick and safe to use multiple build agents. You don't need to understand how it works under the hood, but it can be helpful if you're wondering why Continua does things in a certain way.
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