SDET About the RoleWhat You'll Do

MexicoCosta Rica Until 9/16/2026 4+ years exp First posted July 18, 2026 Last posted July 18, 2026
Job description

About the Role

We're looking for a strong SDET to help us build a scalable, maintainable automated testing practice in a Microsoft/.NET environment. This is a hands-on engineering role focused on API testing and test automation — you'll write clean C# code, design robust test frameworks, and shape how quality is built into our development process from the ground up.


The ideal candidate thinks like a developer and tests like an engineer: someone who's comfortable digging into REST APIs, building automation that scales, and leveraging modern AI-assisted tools to accelerate test creation without sacrificing quality.

What You'll Do

  • Design, build, and maintain automated test suites for REST APIs in a .NET/C# environment
  • Help define and implement a scalable automated testing strategy across the engineering organization
  • Write clean, maintainable C# test code following solid engineering practices
  • Build and improve test frameworks, tooling, and CI/CD integration for automated testing
  • Use AI-assisted development tools (e.g., GitHub Copilot, Claude, or similar) to accelerate test creation and coverage
  • Collaborate with developers to improve testability, catch defects early, and shift quality left
  • Analyze test results, investigate failures, and drive root-cause resolution
  • Advocate for quality best practices and mentor the team on test automation approaches

What We're Looking For:

Required:

  • 4+ years of experience as an SDET, QA Automation Engineer, or similar role
  • Solid understanding of .NET development and hands-on experience writing C#
  • Strong experience testing REST APIs (e.g., using RestSharp, HttpClient, Postman/Newman, or similar)
  • Experience with .NET testing frameworks such as xUnit, NUnit, or MSTest
  • Experience building or extending test automation frameworks
  • Familiarity with CI/CD pipelines (e.g., Azure DevOps, GitHub Actions) and integrating automated tests
  • Comfort using AI-assisted coding tools to speed up test development
  • Strong analytical and debugging skills
  • Professional working proficiency in English (written and spoken)


Nice to Have:

  • Experience with performance/load testing tools (e.g., k6, JMeter)
  • Experience with contract testing (e.g., Pact) or API mocking/virtualization
  • Familiarity with containerized environments (Docker) and cloud platforms (Azure preferred)
  • Exposure to UI automation (e.g., Playwright, Selenium) as a secondary skill
  • Experience working with distributed or remote-first teams

About Tech9

At Tech9, we are driven by a clear mission—to empower organizations with AI-centered solutions that make them more adaptable, efficient, and future-ready. With proven expertise in product strategy, UX design, cloud architecture, and AI, our teams deliver purpose-built software that meets today’s needs and anticipates tomorrow’s challenges.

Headquartered in Utah, Tech9 experts collaborate across the United States, Latin America, and India. We offer a remote working environment with a collaborative and supportive culture, allowing you to focus on what you do best.

If you're excited by the opportunity to work in a fast-paced, innovative environment where scaling and building the future of software is key, we’d love to hear from you. Join us as we work together to redefine the world of software development.


About this role

Summary

Build, maintain, and improve automated API test frameworks in .NET environment.

Job title

SDET

Experience level

4+ years

Minimum experience

4+ years exp

Industry

software

Location requirements

Remote work allowed; candidates in Mexico or Costa Rica preferred.

Salary

Not specified

Management role

No

Skills & keywords

Required skills

C#rest APIsxUnitNUnitMSTestCI/CD

Preferred skills

performance testingcontract testingAPI mockingDockerAzure

Specializations

API testingtest automationC#.NETCI/CD
Locations

Structured locations inferred from the posting.

Mexico

Remote Country

Costa Rica

Remote Country