Nordic Testing Days 2026

People who practice test-driven development (TDD) often describe it as a powerful approach. And while they make a convincing case, nothing beats experiencing it for yourself. So that's exactly what we'll do in this workshop.


We'll start with a brief explanation of TDD's red-green-refactor cycle. Red: write a test for the next bit of functionality you want to add. Green: write the code needed to make the test pass. Refactor: improve the code and the tests. Next, it's time to put that cycle into practice implementing a fairly simple algorithm. There's very little setup needed, so you can do this in any programming language you like.


In the last part of the workshop you'll share you experiences and your code. We'll reflect on those as a group, drawing lessons from it. And we'll discuss how the red-green-refactor cycle applies, even when you're writing something that's not unit testable, like test automation.


Please complete the setup of this workshop beforehand, by following the instructions in the "Setup for the kata"-section of the workshop repo: https://codeberg.org/joeposaurus/counterstring-codekata#setup-for-the-kata. The absolute minimum setup you need to do, is make sure you're able to write code and tests in a programming languague of your choice.


Key takeaways:

1. TDD lets you take small steps with feedback at every step. 
2. TDD lets you discover the right implementation as you go.    
3. The ideas of TDD still apply when you're writing test automation.

Every automation engineer knows the "Maintenance Tax." We spend hours fixing fragile XPaths and CSS selectors just to verify if a button is visible or a chart is correct. In fact, our internal code analysis shows that assertion logic is typically five times (5x) larger in code size than action logic, consuming up to three months of dedicated maintenance effort every year.In this session, I introduce ViTO (Visual Testing Oracle), a production-deployed framework that ends the era of DOM-dependent verification. By leveraging multimodal Generative AI (GenAI), ViTO "sees" the application exactly like a human does.I will share our industrial experience of decoupling verification from the underlying code, resulting in a 50% reduction in our assertion codebase. You will see how we replaced thousands of lines of brittle verification logic with resilient, prompt-driven visual oracles that can handle complex data visualisations and unseen UI faults with zero extra effort. If you are tired of your tests breaking because a div changed, it's time to shift from structural selectors to a visual AI oracle.


Key takeaways:

1. Prompt Engineering for Testers: How to write resilient "Assertion Prompts" that replace complex conditional code and handle visual regression automatically.
2. Real-World ROI: Evidence-based results from a production environment, showing a 50% reduction in code maintenance and expanded coverage for rich UI components.
3. Deterministic AI: Practical strategies to control GenAI hallucinations using "concentrated screenshots" and "dynamic HTML filtering."

This track will be presented by our Gold Partner. Will be announced soon.

How do you test an application that relies heavily on cloud services? Do you have a specific strategy for testing it, or do you simply run your tests regardless of the infrastructure costs?Nowadays, many applications rely on different cloud services, such as databases, message queues, and file storage offered by cloud providers. Those cloud services bring considerable infrastructure costs and complexity in terms of testing cloud applications. The challenges include teams relying on mocks to test the application locally and in CI/CD, as well as extra costs to create test environments that use real services. However, a good alternative to deal with that is to use emulation tools to simulate those cloud services, providing good confidence and saving a lot of costs.In this talk, we’ll explore how Testcontainers and LocalStack offer an affordable and scalable solution to cloud application testing without compromising on quality. This session will demonstrate (including a live showcase) how to use Testcontainers in combination with LocalStack to spin up containerized services to emulate all the AWS cloud services that your application depends on, enabling you to have your own cloud running locally on your machine or CI/CD. Together, those two tools can provide an efficient, cost-saving alternative to traditional cloud testing strategies.Here is the agenda that I plan for this talk:State of cloud applications nowadaysWhat are the challenges when testing cloud applications?Which options do we have to avoid some of those costs?Introduction to Localstack and TestcontainersLocalstack and TestContainers in actionConclusionBy the end of this session, you will have actionable insights on how to optimize your testing process, lower your infrastructure costs, and ensure your cloud applications are ready for production without complex setups.


Key takeaways:

1. Learn how to create and run tests for cloud applications using free and open-source tools while reducing the costs of infrastructure and cloud services.
2. Discover some common challenges when testing cloud applications and how to deal with them.
3. Understand how to use real containerized cloud services instead of mocks to make your tests more closely mimic the production environment setup.