Sr Fullstack /Front End Developer (React + JavaScript) - 12+ years exp is must - Only W2

Job Summary Javascript/React Frontend Engineer with strong Rest API experience, fullstack on Java, .NET or Node.js. Location NYC, NY (Hybrid – 3 days a week in office required). Job Type W2 Contract. Experience Level Senior. Job Description Frontend-Focused Full-Stack Engineer (React + JavaScript) with strong Rest API experience with either Java, .Net or Node.js. Enhance and scale a growing AdTech platform centered on digital advertising capabilities. Emphasize modern frontend development with React and JavaScript while contributing to backend integrations through REST APIs across multiple technologies (Java, .NET, Node.js). Deliver high-performance user experiences for advertising platforms, including campaign management, targeting, measurement, and integrations across media and publishing ecosystems. Key Responsibilities Design and build modern, scalable frontend applications using React and JavaScript (TypeScript preferred). Develop intuitive UI/UX for key AdTech capabilities, including Campaign management dashboards Targeting and personalization interfaces Reporting and analytics views Optimize frontend performance, responsiveness, and usability. Collaborate closely with Product, Marketing, and Design teams to deliver high-quality user-facing features. Backend & API Collaboration Integrate frontend applications with REST APIs built in Java, .NET, or Node.js. Contribute to API design discussions to ensure efficient frontend-backend interaction. Support development and maintenance of backend services where needed, focusing on API contracts Data flow optimization Service integration Platform & Engineering Contribution Scale and enhance an existing AdTech MVP platform to enterprise-grade solutions. Participate in system design discussions, code reviews, and technical planning. Work with cloud-based and distributed systems. Support CI/CD processes, deployment pipelines, and platform reliability. Integrate with advertising platforms such as Google Ad Manager, Koddi, and similar ecosystems. Troubleshoot production issues and improve performance and stability. Required Qualifications 6-8 years of software engineering experience, with strong emphasis on frontend development. Strong expertise in JavaScript (ES6+), React (including hooks, state management, component architecture), and building complex, data-driven UI applications. Experience working with REST APIs (integration and/or design). Experience with modern frontend tooling (e.g., Webpack, Vite, CI/CD pipelines). Understanding of backend systems using one or more of: Java, .NET, Node.js. Experience with cloud-based applications and services. Familiarity with Agile development environments. Understanding of CI/CD, DevOps practices, and application resiliency. #J-18808-Ljbffr Saransh Inc