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Hi, I'm Serhat Yesilmen, a results-driven SDET with 9+ years delivering scalable automation in Agile teams. I specialize in Java, Selenium WebDriver, API testing, and SQL, building robust automation frameworks that boost test coverage and accelerate release cycles.\n\nI design comprehensive test plans and automation strategies for enterprise web, API, and backend systems, and I thrive in collaborative environments that prioritize quality, continuous improvement, and reliable CI/CD pipelines.…Hi, I'm Serhat Yesilmen, a results-driven SDET with 9+ years delivering scalable automation in Agile teams. I specialize in Java, Selenium WebDriver, API testing, and SQL, building robust automation frameworks that boost test coverage and accelerate release cycles.\n\nI design comprehensive test plans and automation strategies for enterprise web, API, and backend systems, and I thrive in collaborative environments that prioritize quality, continuous improvement, and reliable CI/CD pipelines.

Serhat Yesilmen

QA Engineer, Full Stack Developer, Web Developer, +2

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Hi, I'm Serhat Yesilmen, a results-driven SDET with 9+ years delivering scalable automation in Agile teams. I specialize in Java, Selenium WebDriver, API testing, and SQL, building robust automation frameworks that boost test coverage and accelerate release cycles.\n\nI design comprehensive test plans and automation strategies for enterprise web, API, and backend systems, and I thrive in collaborative environments that prioritize quality, continuous improvement, and reliable CI/CD pipelines.…Hi, I'm Serhat Yesilmen, a results-driven SDET with 9+ years delivering scalable automation in Agile teams. I specialize in Java, Selenium WebDriver, API testing, and SQL, building robust automation frameworks that boost test coverage and accelerate release cycles.\n\nI design comprehensive test plans and automation strategies for enterprise web, API, and backend systems, and I thrive in collaborative environments that prioritize quality, continuous improvement, and reliable CI/CD pipelines.

Available to hire

Hi, I’m Serhat Yesilmen, a results-driven SDET with 9+ years delivering scalable automation in Agile teams. I specialize in Java, Selenium WebDriver, API testing, and SQL, building robust automation frameworks that boost test coverage and accelerate release cycles.\n\nI design comprehensive test plans and automation strategies for enterprise web, API, and backend systems, and I thrive in collaborative environments that prioritize quality, continuous improvement, and reliable CI/CD pipelines.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Work Experience

SDET at Meta

May 1, 2021 - Present

Led the development of a Java automation framework, boosting test coverage by 20% and automating UI, regression, and smoke tests to reduce manual effort by 40%. Implemented API testing using Rest Assured and Postman, cutting testing time by 35% and validated microservices-based APIs; performed performance and load testing with JMeter as part of CI/CD pipelines; ensured 99.9% data accuracy via 500+ SQL/JDBC validations; integrated automated tests into Jenkins nightly builds.

Software Test Engineer at CITIBANK

August 1, 2019 - April 1, 2021

Reduced manual testing by 75% by developing 400 Java-Selenium scripts; validated REST APIs via Postman and SQL queries; lowered post-release defects by 18% through regression/functional testing; expanded cross-browser testing to four browsers, cutting regression cycles by 30%; identified 20% latency issue in AWS EC2, achieving 15% performance improvement; automated builds and optimized workflows using Git and Jenkins.

SDET at ABBVIE

October 1, 2017 - July 1, 2019

Streamlined manual testing by 40% with a scalable Selenium framework; enhanced test readability and reusability by implementing a BDD framework; achieved JSON validation accuracy via API testing with Rest Assured; increased data reliability by 60% through backend data integrity validation; cut test cycle time by 70% by automating tests in Jenkins; accelerated sprint goal delivery by 40% through leading Agile Scrum ceremonies.

QA Engineer at INTEGRITY

June 1, 2016 - September 1, 2017

Optimized manual testing time by 40% using Java & Selenium automation; identified 15 critical defects through 200+ Postman API tests; minimized script failures by 15% via Apache POI test data standardization; optimized defect turnaround by 25% with redesigned Jira workflow automation; increased defect detection by 40% executing 150+ sprint test cases.