SDET vs Test Automation Engineer: Main Differences

Treating testing as an afterthought has never been a great idea.

The tech industry seems to recognize the importance of an error-free product, thus raising the global testing market to $1,252 million by the end of 2027.

The rush to the testing-first mind also led to the increased demand for QA gurus in various flavors. Today, we’ll shed light on the differences between the sought-after SDET role and traditional test automation engineers.

Who Is A QA Automation Engineer?

The job of a QA automation engineer is well-known in the tech world. In layman’s terms, they design and write programs for automated test case suites targeted at new or existing software. Therefore, they’re engaged in the core operation during the software development cycle - reducing the number of manual tests.

What Does A Test Automation Developer Do?

A QA automation engineer holds the skills of a programmer and the logic of a tester at the same time. Thus, like QA engineers or testers, a QA automation engineer monitors the quality of a product at various stages of development. And just like developers, they contribute to the development process. In other words, developers create, testers break, and automation engineers create in order to break.

The common set of their responsibilities includes:

• Brainstorming ideas for automated software test procedures;
• Setting up test environments;
• Preparing test data;
• Analyzing test coverage;
• Monitoring software bug reports and flagging critical zones;
• Writing automation scripts and implementing software applications;
• Collaborate with other business units to define improvement areas;
• Communicate with clients and end-users to build the best automation solutions that address the needs of customers.

The Whys and Hows of SDET

Let’s continue with this mysterious position wrapped in myths. SDET stands for Software Development Engineer in Test or Software Design Engineer in Test. Microsoft has dropped this title and is considered to originate the role of SDET. Today, SDETs live in other companies and popular job postings. Essentially, an SDET employer combines the skills of a developer, tester, and DevOps. They are involved in the full software release cycle - from low-level unit tests to senior activities such as test planning. It’s like a Jack-of-all-trades version of a QA engineer who pursued a more technical direction.

What Does A SDET Do?

According to the recent job postings, SDET responsibilities may include:

• Understanding the flow of code and how it interacts with other components;
• Looking into user issues cc’d by the support department;
• Creating reusable scripts/tools upon demand;
• Being proficient in both functional and non-functional areas of testing;
• Providing bug reports and collaborating with the team;
• Writing unit test coverage of the code;
• Contributing to the design and architectural discussions, and others.

Their skill set also allows SDETs to participate in creating test automation frameworks and tools. They also pick the most optimum test automation tools for their teams.

And that’s where it gets confusing. How is that different from an automation engineer?

SDET vs Test Automation Engineer: Core Differences

Most companies don’t differentiate an SDET role as a standalone position. It is usually used interchangeably with “automated tester.”

Therefore, you won’t see any difference in some organizations.

However, an increasing number of companies draw a line between the two. Typically, the distinction can be attributed to the fact that the SDET role predominantly refers to a regular developer position rather than an automated tester.

In a broad sense, SDET can be seen as half a traditional coder and half a tester. However, they’ll be more drawn to the testing stage, instead of fully monitoring the development phase.

To have a closer look at how the two differ from each other, let’s go over the main points:

• SDET engineers boast a diverse set of skills - both in the coding and testing area. On the contrary, testers are in charge of only performing test cases and preparing automation environments.
• SDETs are well-versed in software development, hence they can tap into test automation tool development and streamline it for generic use. Test automation pros don't usually build test automation tools. Instead, they use the automation tools prepared by SDETs.
• If the API testing requires technical knowledge such as writing code, then this task will be handed to an SDET. On the contrary, user interface testing will be assigned to a QA engineer, since no lines of codes are needed.
• Software Development Engineers in Test are responsible for a wider circle of duties, unlike test automation developers.
• From a hierarchical standpoint, QA developers get their tasks from an SDET, since the latter boast domain knowledge.

Now, let’s dump those differences in a succinct table.

Criteria	Test Automation Engineer	SDET
Main goal	Improves the system quality by identifying and preventing errors and bugs	1)Improves the system quality by identifying and preventing errors and bugs 2) Develops automation tools and contributes to implementing the system through the whole development process
Main responsibility	Creates and supports automation tests	Fully owns the testing component of a project
Programming skills	Basic	Advanced
Programming skills	Basic	Advanced
System knowledge	Limited knowledge that lies only in the testing domain (no business expertise)	Knows the ins and outs of the whole system

When do you need to hire SDET?

So, we’ve defined an SDET as a professional at the intersection of a tester and developer. Therefore, if you’re in need of a tester that can both take over test scripts and fix bugs, consider hiring an SDET. This position is an advancement from a QA developer who builds a structure and executes it to flag an issue. SDET extends it further by going beyond conventional extension and including unit tests as well as parts of white box testing. SDET will also become a valuable asset for your company if your product requires end-to-end test automation. They help refine the code quality by conducting rigorous and in-depth source code reviews as well as monitoring the testability of the code.

The Final Word

It’s not easy to live in a world of shift-left testing. However, you can now ease the strain by hiring a Software Development Engineer In Test. SDETs can join your developer team and take over testing-linked tasks like test creation, updates, and automation. And no, QA developers cannot substitute this job role. As we see from the article, it takes more technical knowledge and business-related skills to become an SDET.