Software Developer Engineer in Test

Caristo Diagnostics; Oxford; On-site; GBP 60,000 - 75,000; Full time

Job summary

Caristo Diagnostics in Oxford, UK, is seeking a Software Developer Engineer in Test to strengthen its automation team. You will enhance a Python/Selenium/Behave framework, improve reliability and speed, and extend coverage across tests for medical device software validations.

You will mentor juniors and promote automation-first practices while aligning with ISO 13485/62304 compliance requirements.

Qualifications

• Strong Python programming with OOP and clean code.
• Experience building test automation frameworks with Selenium or Playwright and Behave.
• Knowledge of Page Object Model (POM) and automation design patterns.
• API test automation using requests or similar.
• Experience writing maintainable, reusable, scalable automated test suites.
• Familiarity with Git version control.
• Experience with CI/CD pipelines (GitLab CI).
• Ability to troubleshoot flaky or unstable automated tests.
• Experience with logging, reporting, and test result analysis.
• Strong analytical and problem-solving skills.

Responsibilities

• Enhance and extend the existing Python/Selenium/Behave automation framework.
• Evaluate and introduce improvements to increase reliability, maintainability and speed.
• Refactor and optimise automated tests for stability.
• Increase automation coverage to reduce manual testing.
• Develop reusable automation utilities and libraries.
• Implement coding standards and best practices for automation.
• Maintain comprehensive documentation for the automation framework.
• Train and mentor junior team members.
• Promote automation-first thinking within the testing team.
• Ensure compliance with MDD/MDR and ISO 13485/62304 for software medical devices.

Skills

Python

Selenium

Playwright

Behave

POM

API testing

Git

GitLab CI

Debugging flaky tests

Logging and reporting

Tools

Selenium

Playwright

Requests

Git

GitLab CI

Docker

Allure

Job description

Job Title Software Developer Engineer in Test
Department Engineering
Reports To: Lead Test Engineer
Location: Oxford, UK

Responsibilities

• Enhance and extend the existing Python/Selenium/Behave automation framework.
• Evaluate and introduce improvements to increase the test framework reliability, maintainability and execution speed.
• Refactor and optimise existing automated tests for stability and maintainability.
• Increase automation coverage to reduce reliance on manual testing.
• Develop reusable automation utilities and libraries.
• Implement coding standards and best practices for automation.
• Maintain comprehensive documentation for the automation framework.
• Training and mentoring junior members of the team.
• Promote automation-first thinking within the testing team.
• Compliance with the MDD/MDR and ISO 13485/62304 standards for validation and verification of software medical devices.

Skills & Experience Required:

Essential

• Strong Python programming skills, including object-oriented programming and clean code principles.
• Experience developing and maintaining test automation frameworks using known browser automation framework (e.g Selenium or Playwright) and BDD (e.g. Behave).
• Solid understanding of the Page Object Model (POM) and other automation design patterns.
• API test automation using tools and libraries such as requests or similar.
• Experience writing maintainable, reusable, and scalable automated test suites.
• Familiarity with version control systems (Git).
• Experience working with CI/CD pipelines (e.g. GitLab CI).
• Ability to troubleshoot and resolve flaky or unstable automated tests.
• Experience with logging, reporting, and test result analysis.
• Strong analytical and problem-solving skills.

Desirable

• Experience integrating automated tests into deployment pipelines
• Knowledge of Linux command line
• Experience with containerisation (Docker)
• Familiarity with cloud platforms (AWS)
• Experience with test reporting tools such as Allure
• Understanding of test data management and environment configuration.