Freelance Java Backend Developer Jobs in Hartford, CT

Job#: 3042379
Job Description:
SDET
Location: Hartford, CT, or Wellesley, MA (Partial Remote)
Role Overview
We are seeking two mid to senior-level Software Development Engineers in Test (SDET) to join our engineering team. These contract-to-hire roles are focused on transitioning from traditional QA to an engineering-centric approach by architecting and implementing testing frameworks and tools, particularly for AI agents and conversational AI systems. The ideal candidates will have five or more years of hands-on experience, capable of mentoring others and leading design and development efforts.
Key Responsibilities

• Architect and implement testing solutions, including tools, test harnesses, and frameworks for AI agents and conversational AI systems.
• Collaborate with Product, Architecture, and Engineering teams to define test strategy, coverage goals, and acceptance criteria.
• Design, build, and maintain reusable test harnesses and frameworks that eliminate decision paralysis for engineers.
• Develop and automate test plans for Voice and Chat channels, including validation of complex multi-turn conversations and intent recognition.
• Provide test infrastructure to enable engineering teams to test and own the quality of their services across Java/Node.js backends and APIs.
• Mentor team members on test-driven development, automation patterns, and best practices.
• Monitor and report on test execution and quality metrics to ensure the customer experience is protected and improved.
• Contribute to automated test implementation and general development tasks when harness work is complete.

Required Qualifications
Experience:

• 5+ years of total software engineering experience, with 3+ years focused on test automation or SDET work.
• Hands-on experience architecting and implementing testing solutions.
• Proficiency in at least one backend language: Java or Node.js, with object-oriented design experience.

Technical Skills:

• API testing expertise (REST, validation, mocking) with tools such as Bruno, Postman, SoapUI, Karate, or Rest Assured.
• Experience with UI testing tools like Selenium or Playwright.
• Knowledge of test frameworks such as JUnit, Jest, or Cucumber; experience building custom frameworks is a plus.
• Experience with testing LLM/AI responses, using approaches such as LLM-as-a-judge.
• Understanding of test data strategy, including synthetic data creation and provisioning mock data.
• Familiarity with CI/CD pipelines, such as GitHub Actions.

Other Requirements:

• On-site availability in Hartford, CT, or Wellesley, MA is required.

Preferred Qualifications

• Deep hands-on technical expertise in automation, developing test frameworks, tools, and APIs.
• Experience with conversational AI platforms.
• Experience with contract testing or API mocking tools.
• Knowledge of performance or load testing frameworks.
• Experience testing AI agents and understanding deterministic vs. non-deterministic responses.

Work Environment
The new hires will join existing scrum pods of approximately eight members each. These are critical roles within the team, created to enhance engineering and testing capabilities.
Everforth Apex is a world-class IT services company that serves thousands of clients across the globe. When you join Everforth Apex, you become part of a team that values innovation, collaboration, and continuous learning. We offer quality career resources, training, certifications, development opportunities, and a comprehensive benefits package. Our commitment to excellence is reflected in many awards, including ClearlyRateds Best of Staffing in Talent Satisfaction in the United States and Great Place to Work in the United Kingdom and Mexico.
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Everforth Apex Benefits Overview: Everforth Apex offers a range of supplemental benefits, including medical, dental, vision, life, disability, and other insurance plans that offer an optional layer of financial protection. We offer an ESPP (employee stock purchase program) and a 401K program which allows you to contribute typically within 30 days of starting, with a company match after 12 months of tenure. Everforth Apex also offers a HSA (Health Savings Account on the HDHP plan), a SupportLinc Employee Assistance Program (EAP) with up to 8 free counseling sessions, a corporate discount savings program and other discounts. In terms of professional development, Everforth Apex hosts an on-demand training program, provides access to certification prep and a library of technical and leadership courses/books/seminars once you have 6+ months of tenure, and certification discounts and other perks to associations that include CompTIA and IIBA. Everforth Apex has a dedicated customer service team for our Consultants that can address questions around benefits and other resources, as well as a certified Career Coach. You can access a full list of our benefits, programs, support teams and resources within our 'Welcome Packet' as well, which an Everforth Apex team member can provide.
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