The three aspects that generally differentiate what a Test Engineer does day-to-day depend on the following:

Individual’s Strengths & Interests:
Everyone is different and every TE has different passions, strengths and areas of expertise. Thankfully, Google’s a big enough company that many different areas of testing are available, and we gravitate to testing products we like. All TEs start with core competencies in testing, coding, and algorithms. How a TE applies this knowledge varies.

The Type of Product:
Desktop, web app or mobile? Frontend or backend? The technologies that our products use and run on create a lot of variation in what and how we test.

The Product’s History / Lifecycle:
Early concept products don’t resemble those that exist in production. And the amount of testing that a product already has will determine what testing the TE is focused on. We work creating a test roadmap that parallels the product’s development cycle and addresses any testing gaps.

If you still want to know what the day in the life of a Test Engineer entails, we’ll never be able to give you a general answer for that. Instead I suggest that you check out what Alan Faulkner is doing or ask the next Google Test Engineer you meet.

Interested in joining the ranks of Test Engineers (or Software Engineers in Test)? Check out http://goo.gl/2RDKj

About the Contributors:
Albert Drona has been at Google for 5 years and is currently working on Google Maps for Mobile.
Jatin Shah has been at Google for 9 months on Google+.
Mohammad Khan has been at Google for 7 years and is currently working on Google+ releases.
About the Author:
Yvette Nameth has been at Google for 5 years and is currently working on Google Maps rendering.