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added link to an article about test-driven development.
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- Something that was working last week, or in the most recent build, is not working at all today.
- Users are doing things with the app that you didn't expect them to do, like putting lines of code in a text entry field, and things are blowing up everywhere.
+The main defense you have against buggy code and a failed development project is testing. Test early, test often...consider trying out <a href="https://en.wikipedia.org/wiki/Test-driven_development" target="_blank">Test Driven Development</a>.
+
+Over time we will add pointers to general testing guides, and tips and tricks more specific to Apache Royale. Keep checking back, or consider contributing your own insights.
+
## Unit tests
Apache Royale includes the [RoyaleUnit](testing/royaleunit.html) library for unit testing.
