We tend to contrast automated and manual testing, but really, they should support each other. The key is to define what our testing objectives are, then build the solution needed to achieve them—probably a combination of manual and automated testing. We should not let the method become more important than the results.

There's a recent trend in having generalists on the software team—there are no developers or testers, only "team members." The idea of the two roles learning from each other is a good one, but it's usually a one-way street: Testers learn to write production code or test tooling, but no one focuses on deep testing.

If you have to replace a complex existing data system in production, decisions about when and whether to go live should be treated with gravity and care. One process that can help keep you honest is developing checklists that describe very clearly what is expected to be accomplished and verified at each milestone.