Ready to leverage your innovative expertise to drive the transition from traditional cloud to autonomous AI platforms? Are you ambitious, equipped with razor-sharp analytical skills, and eager to build the indispensable foundation that our AI and data teams depend on? Do you thrive when given a high degree of autonomy? If so, we are looking for you!

Your Contribution to the Adventure

The rise of AI coding tools is changing the software world at breakneck speed: writing code is becoming cheaper and faster, leading to exponential growth in the volume of code we produce. However, more code also means a larger test surface. To prevent our development velocity from stalling over the question, "can we confidently deploy this to production?", we need you. You will become the owner of our automated testing platform and CI infrastructure, ensuring our teams can continue to release at maximum speed.

What does this entail?

System & Architecture: This is not a role where you will simply click through test cases or manually verify code. Your output is the system and the architecture behind the tests. You will design the test framework, manage the test data lifecycle, and build a stable, cross-team smoke suite that spans our markets in NL, BE, DK, and DE.

Tech-Lead & Coaching: Additionally, you are a true tech-lead and sparring partner. You will coach and support teams in writing their own local E2E tests within your platform.
Execution & Communication: You are driven by execution and communication: you collaborate seamlessly with colleagues like Joke and Pasha to translate their exploratory testing insights into rock-solid automated regression coverage.
Autonomous Future: In doing so, you calibrate the confidence within our transition toward fully autonomous product development.

Sven’s tip for new 12Builders:

“Finding your own style and using it to inspire your colleagues is strongly encouraged!”

Who is 12Build?

With a healthy dose of Drive, Openness and Happiness, we are building a transparent construction sector. We are not only a SaaS platform that connects construction companies and promotes collaboration, we are also the market leader in the Netherlands. We have been around for almost twenty years and we are still growing. Our team now consists of more than 90 colleagues, working together from two offices and various home offices throughout Europe. A large part of the construction world in the Benelux, Germany and Denmark already works on our platform and uses our software on a daily basis. And we have the ambition to conquer the whole of Europe!

Our Stack & Tools

Within our development team, we are continuously expanding and improving our own SaaS platform. We work with, among other things:

Testing & CI Infrastructure: E2E test frameworks, CI/CD test gates, Test data lifecycles, Docker, Terraform.
Core Cloud Services: AWS, SNS, SQS, S3, Lambda, and API Gateway.
Development & Data: PHP (Laravel), Vue.js ( Nuxt.js ), TypeScript, JavaScript, MySQL, and OpenSearch.
Collaboration & AI Tools: Claude, Linear, Confluence, and Slack.

What We Expect from You

An organized, methodical, and flexible team player with a clear vision for test automation.
Someone with strong interpersonal and communication skills who actively seeks connection with product teams and other QA colleagues.
A proactive, hands-on leader ("meewerkend voorman") with an independent work ethic, who isn't afraid to dive deep into 'flake discipline' to tackle testing issues at their root.
A strong driving force who tightly structures and safeguards the CI testing phases.
Analytically minded, eager to learn, and always up-to-date with the latest methodologies (such as LLM-as-a-judge frameworks).
Proven experience in software development or software testing, with a track record of setting up robust test platform architectures.

What We Offer You

A starting salary between €5,500 and €6,500 gross per month (based on a senior job level).
A 'Lease a Bike' scheme with a €10 monthly employer contribution.
A home office allowance for the days you work from home.
Free lunch at our office in Nijverdal.
30 vacation days per year.
An exciting role within a growing, international SaaS scale-up.
Flexible work options (hybrid setup: both from home and the office).
Regular team events and ample opportunities for personal and professional development.
Choose your own hardware: Windows, Mac, or Linux—everything is possible.

Working in an organisation where culture really is number one . Read here how we do that.
No towering hierarchical layers. Just a flat organisation with short lines of communication, which makes things easy.

You've taken the time to read this text all the way through. That says it all, right? So feel free to apply!

Do you have any questions or are you still a little unsure? No problem! Feel free to send an email to Leonie from HR ( l.vanmook@12Build.com ).

See you soon!

Agentic Automation Test Engineer