Software Development Engineer in Test (sdet) – ML & LLM Systems

Comcast Comcast · Media · Washington, DC

Software Development Engineer in Test (SDET) focused on ML & LLM Systems, specifically evaluating and validating LLM behavior, performance, and reliability. The role involves designing and implementing automated test strategies, frameworks, and pipelines for ML models, NLP systems, and LLM evaluations, ensuring quality before deployment.

What you'd actually do

  1. Design, develop, and maintain robust automated test code using software engineering best practices, ensuring reusability, reliability, and scalability.
  2. Develop and enhance automated test suites for functional, regression, and performance testing across machine learning models, NLP systems, and supporting backend services.
  3. Design and implement robust test strategies and automation frameworks to support evolving services, workflows, and ML model testing requirements.
  4. Perform model validation and verification, including accuracy benchmarking, regression testing, drift detection, and reproducibility checks before and after deployment.
  5. Investigate failing tests, diagnose root causes, and implement fixes to improve test stability and confidence.

Skills

Required

  • 2+ years of industry experience as a Software Development Engineer in Test (SDET)
  • Strong experience with API testing and solid understanding of RESTful APIs
  • Hands-on experience with test processes, test design, test case creation, and defect management systems
  • Strong coding skills with hands-on experience in Java and Spring Boot, and Python
  • Prior Experience with testing Machine Learning models, NLP services, Large Language Models (LLMs) and LLM evaluation frameworks
  • Demonstrated ability to design, build, and maintain test automation frameworks
  • Comfortable working in Linux environments; hands-on experience with container technologies such as Docker and Kubernetes
  • Experience building or working with CI/CD pipelines using tools such as Jenkins
  • Working knowledge of AWS services, including S3
  • Experience with NoSQL databases such as MongoDB
  • Familiarity with Agile development methodologies and working within cross-functional Scrum teams
  • Strong written and verbal communication skills, with the ability to collaborate effectively across teams
  • Highly detail-oriented, analytical, and proactive, with a strong passion for quality, automation, and continuous improvement

Nice to have

  • Prior Comcast experience preferred

What the JD emphasized

  • LLM evaluations
  • ML quality frameworks
  • model validation and verification
  • test strategies and automation frameworks
  • automated validation pipelines

Other signals

  • evaluating LLM behavior
  • measuring LLM behavior
  • ML quality frameworks
  • LLM evaluations
  • model validation and verification