The differences between unit tests, integration tests, contract tests, end-to-end tests, and behavior tests-and which type is best to use-are often debated. Principles like "don't mock what you don't own" or "test behavior, not implementation" are often cited in those conversations. But there's one key question we should always ask when writing tests: is this a valuable test?

So let's put those other concepts aside and ask a simple question as we look at some real-world examples: "What is the value of this test?" Answering that can lead to more nuanced questions. Does this test continue to deliver value over time? How much value comes from the act of writing this test? Are there ways to increase the immediate value as well as the long term value?

Join me as we rethink testing-not in terms of types and categories, but in terms of the practical, meaningful value that testing brings to our codebases and our teams.

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Joseph Lavin at 10:58 on 21 May 2025

Nice real world examples.

As someone who eats, sleeps, and breathes automated testing I *loved* Tim's reasonable approach (e.g. "here are the 'rules', but here's where you get *value*".

I was a little concerned when it turned into a Battlesnake tutorial in the back-half, but the examples were extremely relevant and tied back nicely to the first half.

Joshua Stroup at 10:59 on 21 May 2025

Great points to quantify the value of a test. Using Battlesnake to demonstrate was a perfect way to wrap up.

Eric/a Seyden at 11:00 on 21 May 2025

Great foundational material for thinking about tests, their value and solid examples of what makes the test code itself useful to a developer.

Tim presented this talk well, keeping the audience interested and learning. The principles and arguments made were helpful in giving value to tests. The live coding was helpful, but the font was pretty small and hard to read. Overall a great talk.

Great new talk from Tim! I appreciated the novel "testing parallelogram" as an evolution of the "testing pyramid" model, and had many takeaways to improve my thinking around value and prioritization of testing, as well as the emphasis and benefit of leaning into TDD. Also appreciated the practical Battlesnake example to give concrete examples to look at together.

The Test Pyramid was brilliant! I loved the commentary on nomenclature and how we tend to get wrapped up in the “right” framework and test types instead of focusing on what value the tests are bringing (or not).

Dana Luther at 15:23 on 22 May 2025

Loved the testing geometry. The concepts here are really sounds and apply well in practice. Well delivered as always, and I haven’t gone to the QR code but I think yes 100% on teaching the presentation style and on the book. Hopefully I’ll remember to go to the forms but wanted to put it here in case…

s w at 22:26 on 22 May 2025

5 stars. Tim's canva board thing works well. Nice to see the forest from the trees.