SrSoftwareEngineer,Java,Springboot

Join us in bringing joy to customer experience. Five9 is a leading provider of cloud contact center software, bringing the power of cloud innovation to customers worldwide. Living our values everyday results in our team-first culture and enables us to innovate, grow, and thrive while enjoying the journey together. We celebrate diversity and foster an inclusive environment, empowering our employees to be their authentic selves. Job Description: As a Sr. Backend Engineer, you will be a key player in our team, responsible for the design, development, and maintenance of our next-generation Billing service. Responsibilities: Design, construct, test, and maintain a highly scalable, event-driven billing service. Build and operate ingestion pipelines that consume usage events from Pub/Sub and other upstream sources. Implement metering, rating, aggregation, and reconciliation logic that guarantees correctness and idempotency at scale. Ensure systems meet business requirements, regulatory needs, and industry best practices. Collaborate with product managers, architects, engineering leaders, and test engineers to deliver new billing capabilities. Drive improvements on billing reliability, accuracy, performance, and cost efficiency. Troubleshoot and support the platform in production, including on-call rotations. Qualifications: 5+ years of software engineering experience. 5+ years of Java backend development, with hands-on experience using Spring Boot. Degree in Computer Science, IT, or similar field; a Master's is a plus. Strong Computer Science fundamentals in design, data structures, algorithms, problem solving, and complexity analysis. Experience designing and implementing RESTful APIs and event-driven services. Strong understanding of event-driven architectures and asynchronous processing. Experience with messaging systems (Pub/Sub, Kafka, or similar) and at-least-once / exactly-once processing semantics. Hands-on experience with the GCP ecosystem (Pub/Sub, GCS, GKE, Clou