Senior Full-Stack Engineer (React focused)

Paychex is reimagining how businesses manage their workforce by bringing payroll, HR, benefits, and advisory services together into a single connected HCM platform. As Paychex and Paycor come together, we're combining innovative technology, data-driven insights, AI, and human expertise to help organizations work smarter, support their people, and achieve better business outcomes. This is an exciting time to join our team as we continue to invest in innovation, simplify client experiences, and shape the future of work. At Paychex, you'll have the opportunity to grow your career, make a meaningful impact, and be part of something bigger as One Paychex. Responsibilities • Build and lead frontend architecture using React, MUI, and high-fidelity Figma design integrations • Own full stack feature delivery with Python on AWS serverless (Lambda) and clean GraphQL API integration • Work closely with Product and Design Agency to define roadmaps, create epics & stories, • Architect and integrate GraphQL APIs to power dynamic content and product experiences across the platform • Collaborate on AI-powered features and intelligent automation interfaces, with rigor in verifying AI-assisted work • Mentor junior engineers, model clean code and BDD/TDD practices, and elevate team performance • Integrate with our fully automated CI/CD pipeline (CircleCI, GitHub Actions) • Help shape our design system and contribute to a scalable, componentized UI foundation Qualifications 5+ years full stack development experience (focus on React and exposure to Python/AWS serverless) Deep knowledge of React, MUI, and scalable frontend systems Experience with GraphQL and API-driven frontends Background in AI-powered features and intelligent UI flows Strong testing and clean coding mindset (BDD, TDD, SOLID)• DevOps-aware mindset (CI/CD with CircleCI and GitHub Actions, observability with Datadog or equivalent, rollback readiness) Experience leading product delivery: roadmaps, epics, planning, collaboration Experience building and supporting distributed, event-driven systems, including integrations with third-party services and designing for resilience and failure recovery. Strong sense of production ownership, including deployment, monitoring, incident management, and operational support. Solid testing and verification mindset, with a focus on delivering reliable, high-quality software in environments where accuracy and correctness are critical. Experience using AI-powered tools What's in it for you? A flexible work philosophy Company paid private health insurance Company paid life and disability insurance Paid leave for illness, birth parents, non-birth parents, elder caregivers, marriage, adoption of a child and bereavement Inclusive and accessible Employee Assistance Program (EAP) to help with everyday challenges Christmas and Easter bonuses Opportunity for strengthening expertise and skills through Paychex’s learning platform, including lessons in English   Not sure if you meet every requirement? At Paychex, we know that great talent comes in many forms. If you're passionate about the role but don't check every box, we still encourage you to apply. You might be the right fit - either for this position or another opportunity with us. Paychex is an equal opportunity employer. We are committed to fostering a respectful and inclusive workplace where all individuals are treated fairly and evaluated based on their qualifications, experience, and merit. We comply with all applicable federal, state, and local laws prohibiting discrimination in employment.