What is a software engineer in test? (With duties and skills)

By Indeed Editorial Team

Published 14 November 2022

The Indeed Editorial Team comprises a diverse and talented team of writers, researchers and subject matter experts equipped with Indeed's data and insights to deliver useful tips to help guide your career journey.

The development of new technology and software happens in multiple stages including design, coding, testing and maintenance. A challenging occupation that calls for hard skills in computer science alongside communication and time management is working as a software development engineer in test. This is a recently defined role, so it can be helpful to understand what it is before pursuing this career. In this article, we answer the question 'what is a software engineer in test?', where they fit in the development pipeline compared to manual testers and the skills and experience helpful in the role.

What is a software engineer in test?

Aspiring programmers and software engineers might ask 'What is a software engineer in test?' as the role itself, sometimes known as a software development engineer in test (SDET), has some important distinctions. An SDET is a computer scientist who has the ability to write and assess automated testing programs using programming code based on a set of criteria. Software development engineers in test may evaluate their code and make improvements as necessary to improve the end-user experience while developing it.

Related: How to become a software development engineer in test: A guide

What do software development engineers in test do?

Some of the tasks that SDETs do include:

  • Establish, monitor and maintain automated testing: An SDET's main responsibility is to create software that runs tests on existing programs. As a result, a large portion of their work involves writing automated tests and assessing their accuracy and effectiveness.

  • Design test plans and cases: As part of the formulation of test plans and phases, SDETs work with the development team to understand what features they're working on and what could potentially break. In addition to creating new testing plans, SDETs may enhance the test code already in place or create tests that are quicker or more thorough than the ones already in place.

  • Understand the needs of a product to advise on and design testing strategies: To be able to assess what needs to be tested and how best to achieve it, SDETs work to understand as much as they can about the product and its intended goals. They use this knowledge as a guide for designing testing strategies that help ensure the quality of the product.

  • Compile and report results in an automated manner and in real-time: To better help the development team track their progress, effective SDETs are able to quickly generate reports on the tests. These reports support the team in making decisions about what they can fix and what the priorities are.

  • Communicate technical information to clients: In some cases, the SDET may be responsible for communicating technical information between the development team and the clients themselves. This includes being able to take jargon and complex concepts and explain them in a way that's easy to understand.

Related: What is software development and why is it needed?

Software development engineers in test vs manual testers

Manual testers and SDETs have separate jobs and job requirements, although they may appear to be very similar. A manual tester is someone who, as the name suggests, tests software manually. A manual tester's tasks are entirely centred around the testing itself. The key differences between a manual tester and a software development engineer in test include:

Duties, roles and expectations

A manual tester focuses on the actual testing of software, while an SDET focuses on developing tests, running the tests and coding adjustments or changes mid-project. An SDET may also be responsible for communicating technical information about the product to clients or other stakeholders. Manual testers are generally considered to sit lower in the organisational hierarchy than SDETs in terms of job duties and responsibilities.

Related: Key software engineer responsiblities (plus skills)

Skills and abilities

Manual testers don't focus on how to code to be effective in their role, while SDETs have coding skills. An SDET has a deeper and more extensive understanding of the operation of the entire product they're evaluating than a manual tester does, both because of their coding skills and their involvement in the development of the tests themselves. Manual testers may be new to the testing process itself or even the software development industry itself.

Related: 6 essential software engineer skills

Extent of involvement

Manual testers assist at the end of the development process to test a product before it's released. An SDET is generally present throughout the full software generation cycle, typically involving design, development and testing. SDET's may also be more active in suggesting changes or improvements to the product during its development.

Related: Guide: 10 different software engineer levels (plus duties)

Important skills for software development engineers in test

While the specific skills required for the role of SDET vary depending on the organisation and project, there are some key skills that are essential for all software development engineers in test. These include:

  • Coding skills: As an SDET, you're expected to have coding skills. This means being able to write code in at least one programming language and understand code written in other languages.

  • Understanding of testing methodologies: Effective SDETs have a good understanding of different testing methodologies and how they apply these methodologies to different types of software projects. Keeping up to date with the latest tools and strategies is also beneficial.

  • Computer engineering: An SDET understands computer engineering as a whole, including understanding how hardware and software work together, including a familiarity with networking concepts. These skills help them design more effective tests and understand the results of those tests.

  • Analytical skills: A key part of success in this role is analysing data and results to identify issues and areas for improvement. Being able to consider not only the issue itself but consider the impact changing it would have on the project as a whole is very beneficial.

  • Attention to detail: This role requires a high level of attention to detail, as even small changes can have a big impact on the product. SDETs are able to keep details in mind from one test to another, helping them to be more efficient as they're less likely to retest the same item twice.

  • Communication skills: Communicating effectively is essential in this role, as it works with a range of different people, including developers, clients and other stakeholders. Simplifying complex information, articulating complete information and maintaining a positive attitude are all helpful communication skills.

  • Time management and organisation: This role can often be fast-paced and require quick turnaround times. Having strong time management and organisation skills helps SDETs to stay on top of their workload and meet deadlines.

Related: What is software testing? Types, benefits and principles

SDET work environment

SDETs are in the same teams as software developers and may collaborate with them regularly. Some organisations have an SDET on staff, while other SDETs may work freelance or consult with several organisations. The work environment for an SDET can be both office and remote-based.

Work hours are typically regular business hours, Monday to Friday. Given the digital and often online nature of the role, some SDETs work overtime or are on call outside of these hours to accommodate the needs of clients or stakeholders in different time zones. Those working in faster-paced environments may also work longer hours to meet deadlines.

Related: Why testing in software engineering is essential (6 reasons)

Training and qualifications for SDETs

There's no specific educational route to becoming a software development engineer in test, though many SDETs have a bachelor's degree in computer science or a related field. It's also beneficial to have experience working with various coding languages and testing tools. Many organisations offer on-the-job training for SDETs, providing an opportunity to gain real-world experience using the technical skills learned elsewhere.

Degrees to consider for this role include:

  • computer programming

  • computer science

  • computer engineering

  • software engineering

  • software design and development

  • software testing and quality assurance

Related: How to become a software engineer (plus key skills)

Industries hiring SDETs

With the world relying more on technology, there's a growing demand for testing products before launch. SDETs can help support the development and launch of new technology in industries including:

  • finance: to test new software used by banks or financial institutions before making it available to customers

  • telecommunications: to test the performance of new mobile apps or network infrastructure

  • healthcare: to test medical devices and software, such as electronic health records before they're used in hospitals or clinics

  • retail: to test e-commerce platforms or in-store technologies, such as self-checkout kiosks, before being rolled out to customers

  • gaming: to test video games for bugs and glitches before release

  • web development: to test the functionality of websites and apps before they're made live

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