Senior Backend Engineer – Cortex

About the role

As a Senior Backend Engineer on the Cortex Management Team, you will design, develop, and maintain backend software solutions that support Five9’s AI initiatives. The role focuses on building scalable, reliable, and high‑performance backend systems that power end‑to‑end platform capabilities while collaborating closely with product owners and stakeholders.

Key responsibilities

• Design and implement scalable microservices and REST APIs using Java and Spring Boot.
• Write high‑quality, efficient, and maintainable backend code following best practices.
• Troubleshoot and resolve complex production and architectural issues.
• Collaborate with product managers, frontend engineers, and QA to ensure alignment on requirements and delivery.
• Document services, technical specifications, and API contracts.
• Mentor junior engineers and promote backend engineering best practices across the organization.

Required profile

• 5+ years of industry experience in Java backend development.
• Bachelor’s degree (or equivalent) in a relevant discipline.
• Strong understanding of security best practices and ability to implement protective measures.
• Proven ability to work both independently and within a collaborative engineering team.
• Demonstrated experience mentoring developers through guidance and code reviews.

Required skills

• Java
• Spring Boot
• REST API design and implementation
• Microservice architecture
• SQL, NoSQL, Redis
• Google Cloud Platform (GCP)
• Kubernetes
• Gradle
• GitLab CI/CD pipelines
• Event‑driven messaging systems
• Contact‑centre technologies (IVR, Virtual Agents, VoIP)
• Claude AI development tool