Software Development Engineer in Test (SDET)

Overview: Are you an engineer who’d rather build the machine that finds the bugs than click through the same regression suite every release? Have you already started using AI in your test pipeline (generating tests, triaging failures, pruning flaky suites) and want a team that will let you take it all the way? If you want to own quality as an engineering discipline rather than a release-day checkpoint, this could be the opportunity for you.

About Sound Decisions: This position is posted by Sound Decisions Recruiting on behalf of a client. Sound Decisions is a technical recruiting firm led by a software engineer, focused on matching engineering talent with strong teams.

Written From the Perspective of Our Client: We build highly scalable, reliable merchant payment technologies. Our platform calculates a merchant’s exact card-processing cost on every transaction before authorization, and manages compliant surcharging across a shifting set of state, provincial and card-brand rules. When our rules engine is wrong, a merchant is out of compliance. That is why we treat quality as a first-class engineering problem.

We use modern AI tools to accelerate implementation, improve documentation and increase test coverage. AI is an engineering aid, not a substitute for judgment, review or accountability. We are now building an AI-assisted delivery pipeline, and this role owns its quality layer. Our philosophy is explicit: AI exists to make the engineers already here more capable, and it is judged on whether it does.

What experience we’re looking for:

• 4+ years as an SDET, test automation engineer, or software engineer with heavy test-framework ownership, or equivalent demonstrated proficiency.
• Production-quality coding in C#/.NET, TypeScript/JavaScript, or Python. We mean real test code, not recorded scripts.
• Hands-on experience building UI and API automation with modern frameworks (Playwright, Cypress, Selenium) and REST/API testing (RestSharp, Postman/Newman, REST Assured, Pact or similar).
• Experience wiring automated suites into CI/CD (GitHub Actions, Azure DevOps, GitLab CI, Jenkins) as quality gates, with parallelization and reporting.
• Real, recent use of AI in testing, for example:
• LLM-generated test cases from specs or stories
• AI-assisted failure triage or flake detection
• agentic test runners
• Claude, Copilot or Cursor workflows built into a test pipeline

( Note: This experience does not have to come from a professional setting, but the expectation is that it can be delivered at a professional level.)

• Solid SQL, and comfort validating data directly in PostgreSQL or similar.
• The instinct to break things: boundary values, non-happy paths and combinatorial rule testing.

We expect: Managing Up (Working with Superiors):

• Understand priorities
• Provide solutions, not just problems
• Anticipate needs
• Build credibility

You will develop and learn: Leading Quality Across the Team (as you grow with us):

• Set the bar for what “done” means
• Coach engineers to write testable code and own their own tests
• Remove obstacles to fast, safe releases
• Foster psychological safety, where finding a bug is a win and not a blame event

What Behaviors define success in this role:

• Experienced at managing your time and accountable for your actions
• Great at communicating:
• Polished writing and speaking in all communication channels
• Writing bug reports that let an engineer reproduce the issue on the first try
• Explaining quality risk and release tradeoffs to engineers, product and business counterparts
• Able to work with minimal supervision, balance multiple activities and meet deadlines
• Operating with integrity. Green builds mean something because you never fake them
• Being able to quantify knowns and unknowns, including what is covered, what isn’t, and the risk of each
• Strong sense of risk awareness, especially where money and compliance are involved
• Always learning new tools, and testing them before trusting them
• Great at code reviews, especially on test code, delivering criticism in a constructive and helpful way

You value preparation in all things. You research a failure, isolate it and gather evidence before escalating it to the wider team.

What Behaviors we see as counterproductive:

• Poor time management
• Not asking questions when the situation calls for it
• Being inconsiderate of other people’s time, such as filing a bug that says …