A popular approach used with Agile development is the idea of Continuous Integration and/or Continuous Delivery. The terms are interchangeable but the approach typically consists of a source code repository and the ability to deploy code to its appropriate home. For example, a development team might check-in code changes during the day and an automated build process (based on a set of rules) checks-out the code, compiles it and deploys it within an application server.
Because of the frequency of deployment, successful component testing relies heavily on test automation. This is incorporated into the build process to ensure deployed code functions correctly by executing a series of tests against it and reporting the result.