W2 - Senior Backend Engineer – Node.js (Payments Domain)

Job Title: Senior Backend Engineer Node.js (Payments Domain) Location: Johnston, New Jersey (Onsite) Employment Type: Contract (W2) Open Positions: 3 Start Date: Immediate Job Description We are seeking experienced Senior Backend Engineers with strong Node.js expertise and hands-on experience in the Payments domain. The ideal candidate will have a proven track record of designing and developing scalable payment APIs, transaction processing systems, and microservices in a cloud-native environment. Required Skills & Experience • 5+ years of backend development experience using Node.js and TypeScript • Strong experience designing and building payment APIs and microservices • Hands-on experience integrating payment gateways such as Stripe, PayPal, Braintree, or similar platforms • Deep understanding of payment standards including PCI-DSS, PSD2, and ISO 8583 • Experience with transaction processing, reconciliation, and settlement workflows • Strong knowledge of payment security concepts including tokenization, encryption, and fraud detection • Experience working with PostgreSQL, MongoDB, and Redis • Hands-on experience with AWS services including EC2, Lambda, S3, RDS, and SQS • Daily hands-on usage of AI-assisted coding tools such as GitHub Copilot, Cursor, or Claude Code (Mandatory) Preferred Qualifications • Experience with digital wallets and card network integrations (Visa, Mastercard) • Knowledge of chargeback handling and dispute management processes • Experience working in high-volume payment processing environments • Strong problem-solving and system design skills Responsibilities • Design, develop, and maintain scalable backend services and APIs • Build secure and compliant payment processing solutions • Integrate with payment gateways and financial systems • Optimize application performance, reliability, and scalability • Collaborate with product, architecture, and engineering teams • Implement best practices for security, testing, and deployment • Leverage AI coding tools to improve development efficiency and code quality Work Authorization Open to candidates authorized to work on W2.