Have you ever wondered who ensures that code doesn’t break before reaching the user? In times of daily releases and automated pipelines, this responsibility goes far beyond simply running manual tests. This is where the SDET comes in, a professional who is transforming how companies build and validate software.
The Software Development Engineer in Test is the natural evolution of traditional QA. As the market accelerated its deliveries with agile practices and DevOps, it became clear that we needed someone capable of building test infrastructure, not just running tests. According to data from Softjourn, there are currently more than 2,500 open positions for SDETs on LinkedIn alone, indicating a growing global demand for these professionals.
In this article, you’ll understand exactly what an SDET does, how they differ from other roles, and why modern teams are investing heavily in this profile.
What is an SDET?
SDET stands for Software Development Engineer in Test. In simple terms, it’s a developer who builds infrastructure and automation to ensure software quality. The fundamental difference lies in the focus: while a traditional developer writes product code, the SDET writes test code and tools that ensure the product works.
The term was coined by Microsoft and quickly adopted by giants like Google, Amazon, and Adobe. The role emerged from the need to scale testing in agile environments, where short development cycles required fast and reliable technical feedback.
An SDET doesn’t just test, they develop solutions that make tests more efficient, resilient, and integrated into developers’ workflows.
SDET vs QA Engineer vs Manual QA: understanding the differences
Although the roles complement each other, there are important practical differences:
- Manual QA focuses on executing exploratory tests, validating requirements, and identifying issues through direct interaction with the system. Their work is essential for capturing usability issues and complex scenarios that automation still can’t cover well.
- QA Engineer (QAE) already works with test automation, creating scripts that validate functionalities in a repeatable way. Their focus is on the testing layer, ensuring adequate coverage through tools like Selenium or Cypress.
- SDET goes beyond: they develop complete frameworks, CI/CD pipelines, internal tools, and test architecture. They don’t just automate individual test cases—they build the infrastructure that allows the entire team to scale their quality efforts.
It’s important to emphasize that this isn’t a hierarchy. These are complementary roles that, together, form a robust quality strategy.
What does an SDET do day-to-day?
An SDET’s responsibilities are technical and varied.
They develop and maintain test automation frameworks that serve as the foundation for the entire team. They create internal tools that facilitate the work of QAs and developers, such as coverage dashboards or automatic test data generators. They integrate tests into CI/CD pipelines, ensuring that each commit is validated before going to production.
The SDET works closely with developers from the beginning of the cycle, participating in architecture discussions and code reviews. They build performance, load, integration, and API tests, going far beyond simple interface validations.
Imagine your team needs to test 50 different microservices daily. The SDET creates the structure that allows running all these tests in parallel, organized, and with consolidated reports. They transform chaos into process.
Why are companies hiring SDETs?
The business value is clear. SDETs accelerate the development cycle without compromising quality. They drastically reduce costs with bugs in production. According to the IBM System Science Institute, discovering and fixing a bug in QA costs about 15 times more than finding it in the design phase, and 100 times more if discovered in production.
Additionally, SDETs scale testing capacity without linearly increasing team size. A single well-positioned SDET can multiply the efficiency of the entire quality team through the tools and frameworks they build.
Release reliability improves significantly, facilitating the adoption of DevOps practices and continuous delivery. In a market where speed and quality are no longer negotiable, having SDETs on the team has become a competitive advantage.
How TestBooster.ai boosts the SDET’s work
TestBooster.ai was designed as a single quality hub that connects all of a company’s quality initiatives. For SDETs, this means real efficiency.
The platform works as an automation centralizer: you can transfer your existing tests in Selenium, Cypress, Playwright, and other tools into a single place, with unified reports and dashboards. You don’t need to abandon what already works, just organize it better.
With natural language testing, the SDET can democratize the creation of simple tests while focusing their energy on more complex cases. Describing the flows that should be tested and letting the AI generate the test saves valuable time.
The dashboards facilitate communication with managers and provide a holistic view of quality, something SDETs know is essential but usually consumes hours of manual work to consolidate.
For API testing, the platform offers integrated validation without needing to build infrastructure from scratch. And with scheduling and parallel execution, you scale your tests without adding operational complexity.
More quality for your software
The SDET is the professional who bridges code and quality in a structural way. They don’t just validate whether the software works, they build the infrastructure that ensures quality is scalable, measurable, and integrated into the development process from the start.
For teams that want to grow without compromising deliveries, having SDETs is essential. And having the right tools multiplies the impact of these professionals.
If you’re an SDET or lead a quality team, discover how TestBooster.ai can be your ally to centralize automations, scale tests, and provide real visibility into your quality efforts.
