Zeta is seeking a Software Development Engineer II - Backend to build and enhance large-scale transaction processing systems for the payments industry. The role involves working with various product teams to gather requirements and add capabilities, utilizing cutting-edge cryptography for secure payments, and mining large datasets for actionable insights. The engineer will also develop low-level infrastructure to improve network performance and identify solutions for complex problems. Responsibilities include researching and evaluating new tools and technologies to enhance system value. This position requires a Bachelor's/Master's degree in engineering and over 3 years of experience in building enterprise systems, with a strong focus on Java applications, distributed systems, scalability, availability, relational and NoSQL databases, concurrency, and cloud platforms like AWS/Google Cloud/Azure.