Staff Software Engineer

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.  We are expanding our engineering team in India (Bangalore or Chennai) and are seeking a Staff Software Engineer to help design, implement, and scale Five9’s next-generation cloud-native services. This role is ideal for engineers who thrive on hands-on coding, technical depth, and building complex distributed systems.*This position is based out of one of the offices of our affiliate Acqueon Technologies in India, and will adopt the hybrid work arrangements of that location. You will be a member of the Acqueon team with responsibilities supporting Five9 products, collaborating with global teammates based primarily in the United States. Key Responsibilities Design, develop, and optimize high-performance microservices using Java and Spring Boot. Write clean, maintainable, and testable code, with a strong focus on scalability, reliability, and performance. Take ownership of services end-to-end — from design and implementation to deployment, monitoring, and ongoing operations. Collaborate with architects and senior engineers on system design, technical reviews, and problem-solving. Ensure services meet SLAs, performance metrics, and security standards. Contribute to improving CI/CD pipelines, automation, and observability to reduce manual effort and improve service reliability. Provide technical guidance and mentorship to mid-level and junior engineers through code reviews, pairing, and knowledge sharing. Stay current with evolving technologies and help evaluate and adopt tools that strengthen our platform. Required Skills & Experience 10+ years of professional software engineering experience, with significant hands-on backend development. Deep expertise in Java with strong experience in Spring and Spring Boot. Proven ability to build and operate distributed, cloud-native microservices at scale. Strong experience with GCP services (e.g., GKE, Pub/Sub, BigQuery, CockroachDB, Redis) or other cloud providers. Solid understanding of system design, data structures, algorithms, and performance optimization. Experience with Kubernetes, containerization, and CI/CD pipelines (GitLab or similar). Practical knowledge of SQL and NoSQL databases and caching strategies. Strong debugging and problem-solving skills, with an ability to dive deep into complex production issues. Preferred Skills (Nice to Have) Exposure to voice and telephony systems (SIP, RTP, IVR, call routing) or real-time communication platforms. Experience in latency-sensitive, high-throughput systems. Familiarity with Looker, analytics pipelines, and large-scale reporting systems. Technology & Tools Languages & Frameworks: Java, Spring, Spring Boot Cloud & Infrastructure: GCP (GKE, Pub/Sub, BigQuery, CockroachDB, Redis), Kubernetes DevOps & CI/CD: Git, GitLab CI/CD Collaboration & Documentation: Swagger, JIRA, Confluence Hardware: Apple MacBook options available Why Five9? As a Staff Engineer at Five9, you will work on core backend services that power our global cloud contact center platform. You’ll have the opportunity to tackle hard engineering problems at scale, remain deeply involved in coding, and contribute to a culture that values craftsmanship, innovation, and technical excellence - while mentoring others and shaping best practices along the way. Five9 embraces diversity and is committed to building a team that represents a variety of backgrounds, perspectives, and skills. The more inclusive we are, the better we are. Five9 is an equal opportunity employer. View our privacy policy, including our privacy notice to California residents here: . Note: Five9 will never request that an applicant send money as a prerequisite for commencing employment with Five9.