Principal Software Development Engineer in Test

US Mobile is looking for a Principal-level SDET to own and elevate our quality engineering practice. This is a technical leadership role for someone who has built, scaled, and stabilized automated test platforms in modern microservices environments.

You’ll lead by example, designing test strategy, improving CI pipelines, mentoring engineers, and ensuring quality is embedded across the SDLC.

• Own test architecture and automation strategy across backend and frontend systems.
• Design, build, and maintain scalable automated test frameworks.
• Lead end-to-end, API, integration, and UI automation.
• Drive adoption of best-in-class testing practices.

• Build and maintain pipelines using Selenium, Playwright or Cypress. (Currently using Cypress)
• API testing.
• Improve test stability, performance, and execution time in CI/CD.
• Actively debug flaky tests and CI failures.

• Test Java / Spring Boot microservices.
• Validate async workflows (RabbitMQ).
• Test data persistence layers (MongoDB).
• Ensure quality in AWS-based distributed systems.
• Partner with Dev Ops to improve pipelines and observability.

• Mentor Software Engineers on test design and automation.
• Establish coding standards and review practices for test code.
• Influence product and engineering leaders on quality risk and release readiness.

• 5+ years in Quality Engineering / Test Automation.
• Senior or Staff-level experience in a product-driven org.
• Deep expertise with Selenium, Playwright, Cypress.
• Strong Java background (writing production-quality test code).
• Experience testing microservices & distributed systemsCI/CD experience (Git Hub Actions, Jenkins, Git Lab, etc.).
• Strong Linux fundamentals.
• Proven ability to lead and influence.

• Contract testing (Pact or similar).
• Performance testing experience.
• Cloud-native testing in AWS.
• Observability-driven testing (logs, metrics, traces).
• Prior experience building QA orgs from messy to mature.

• Competitive salary.
• Flexible working hours.
• Supplemental health insurance.
• Professional development stipend.
• $500 wfh tech set-up reimbursement.

Salary: $140,000 - $180,000 a year