Senior SDET Java API Performance Testing Automation

3Core Systems, Inc; Chicago, Northern (IL, KY); Hybrid; USD 110,000 - 150,000; Full time

Job summary

3Core Systems, Inc is seeking a Senior SDET for Java API performance testing automation in Chicago. The role involves extending the testing automation framework using Java/JavaScript, taking ownership of test strategy, and developing automation test cases within the existing framework.

You will lead test automation for CI/CD, design and maintain API test suites, mentor onshore and offshore teams, collaborate with product owners, and use tools like Java, Karate, and JMeter to test REST APIs and

Qualifications

• Experience designing and building test automation frameworks.
• 8+ years in test automation framework design.
• 3-5 years testing REST APIs and Web services.

Responsibilities

• Develop API and UI test automation for CI/CD pipelines.
• Mentor engineers across onshore and offshore teams.
• Coordinate with product owner to resolve issues.

Skills

Java

Cucumber

JBehave

REST APIs

SQL

JMeter

Python

Agile

CI/CD

Jenkins

Git

Load testing

Performance testing

Microservices

Tools

Karate

AWS

Apigee

Jenkins

Git

Job description

Senior SDET Java API Performance Testing Automation

Chicago, United States | Posted on 08/06/2026

Job Overview

The Senior SDET will extend testing automation framework using JAVA/JAVA Script, take ownership in understanding business requirements/ACs and develop test strategy/test plan, and develop automation test cases using existing automation framework.

Responsibilities

• Develop test automation code for Continuous Integration (CI), Continuous Delivery (CD), of systems, infrastructure, and test framework.
• Plan, design, develop, and maintain API test automation framework that facilitates automation scripting, execution, and analysis of results.
• Provide technical leadership and mentoring for test engineers on multiple applications/projects onshore and offshore; train and mentor project team members to create, execute, analyze, and maintain automated regression suites.
• Coordinate with product owner to resolve open issues/enhancements/upgrades and understand the use of a specific functionality as needed.
• Develop automated functional scripts using tools such as Java, Karate, JMeter.
• Perform exploratory and manual testing of the product suite as appropriate.
• Provide expertise in testing methodologies, best practices, and standards.

Required Skills

• Strong design and development skills in:- **Java** (3-5 years)
• **Cucumber** (3-5 years)
• **JBehave** or other BDD testing frameworks
• At least **8 years** of test automation framework design.
• **3-5 years** of experience testing Webservices (REST APIs).
• Proven experience developing test scripts, test cases, and test data.
• Ability to write queries in **SQL** or other relational databases.
• **3+ years** of experience developing scenario-based performance testing using **JMeter**.
• Experience testing full stack and integration testing with 3rd parties.
• End-to-end system integration testing experience for software platforms.

Desired Technical Skills

• Hands-on experience with **Python**.
• Development experience in **AWS** Cloud technology.
• Experience in **TDD**, continuous integration, code review practice is strongly desired.
• Experience with **Apigee** or other API gateways is a plus.
• Experience with **DevOps** concepts and tools (e.g., CI/CD, Jenkins, Git).
• At least 2 years working on an Agile team with a solid understanding of Agile/Lean practices.
• Understanding of a microservice architecture.
• Experience in load and performance testing.
• Strong documentation skills.