Senior Full Stack Java Developer Jobs in Holtsville, NY

FlexTrade Systems is a provider of customized multi-asset execution and order management trading solutions for buy- and sell-side financial institutions. Through deep client partnerships with some of the world's largest, most complex, and demanding capital markets firms, we develop the flexible tools, technology, and innovation that deliver our clients a competitive edge. Our globally distributed engineering teams focus on adaptable technology and open architecture to develop highly sophisticated trading solutions that can automate and scale with your business strategies.

At FlexTrade, we hold our values close to heart, with pride and gratitude, as they guide us in everything that we do. We are dedicated to giving our clients a competitive edge, taking ownership of our responsibilities, being flexible to adapt to ever changing environment and technology, bringing integrity to ever interaction and we continue to improve, grow together, and collaborate as one team. All of these, while having Fun, truly make FlexTrade a wonderful place to work.

We are looking for an experienced QA Team Lead to own quality across a complex, multi-technology product suite. You will bridge the gap between hands-on technical testing and team leadership — driving test strategy, building out automated coverage, and coaching a team of QA engineers to raise the quality bar across every release. This role sits at the intersection of C++, .NET, Java, and modern web technologies, requiring broad technical depth and strong organizational skills.

• Define and own the overall QA strategy for manual and automated testing across all product areas.
• Lead, mentor, and grow a team of QA engineers, conducting regular 1:1s, code/test reviews, and performance feedback.
• Collaborate with engineering managers, product owners, and developers to embed quality at every stage of the SDLC.
• Prioritize the team's workload and manage QA effort across concurrent feature streams and bug-fix cycles.
• Report on quality metrics, test coverage trends, and automation ROI to engineering leadership.

• Architect, build, and maintain automated test suites covering UI and backend APIs across C++, .NET, Java, and web stacks.
• Select and champion appropriate automation frameworks (e.g. Selenium/Playwright for UI; RestAssured, Postman/Newman, or equivalent for APIs; GoogleTest/Catch2 for C++ components; NUnit/xUnit for .NET).
• Increase automation coverage continuously — identifying gaps, writing new suites, and refactoring brittle tests.
• Integrate automated tests into CI/CD pipelines to provide fast, reliable feedback on every build.
• Define standards for test data management, environment configuration, and automation best practices.

• Lead and execute structured manual testing of UI features, ensuring functional correctness and consistent user experience.
• Verify application behavior against relevant system, application, and audit logs; esc
• Perform exploratory, regression, and edge-case testing across new and existing features.
• Triage incoming defects, reproduce consistently, and validate fixes prior to release.

• Create, review, and maintain comprehensive test cases and test suites in the team's test management tool.
• Ensure test cases are kept up to date as requirements and implementations evolve.
• Review test coverage against acceptance criteria and flag gaps to product and engineering stakeholders.
• Define and enforce consistent test case naming conventions, traceability, and documentation standards.
• 5+ years of QA experience, with at least 1–2 years in a lead or senior role.
• Proven track record designing and delivering automation frameworks for both UI and API testing.
• Strong proficiency in at least two of C++, .NET/C#, Java for writing and reviewing test code.
• Experience testing web front ends with modern automation tools (Selenium or similar).
• Solid API testing experience including REST endpoint validation, contract testing, and schema verification.
• Confident log analysis skills — reading application, system, and structured logs to diagnose defects.
• Experience maintaining and improving test cases in a test management tool (e.g. Xray).
• Excellent communication skills — able to present quality status clearly to both technical and non-technical stakeholders.

• Exposure to performance, load, or security testing disciplines.
• Familiarity with behavior-driven development (BDD) and tooling such as Cucumber.
• Experience working in regulated or safety-critical software environments.
• Knowledge of containerization (Docker, Kubernetes) for test environment management.
• Experience with FIX protocol or trading systems

• A senior, high-impact role with genuine influence over engineering quality practices.
• A collaborative, multi-disciplinary engineering team building complex, real-world software.
• Competitive salary and discretionary bonus reviewed annually.
• Budget for professional development, certifications, and conference attendance.

FlexTrade Systems, Inc. does not accept unsolicited resumes from search firm recruiters. Fees will not be paid in the event a candidate submitted by a recruiter without an authorized agreement for a particular SOW (Statement of Work) in place is hired: such resumes are deemed the sole property of FlexTrade Systems, Inc.

FlexTrade Systems, Inc. is an equal opportunity employer and makes employment decisions without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, protected veteran status, disability status, or any other status protected by law.