Senior Backend Engineer - Stateful, Exactly-Once Systems

Humana; Colorado; Hybrid; USD 107,000 - 147,000; Full time

Job summary

Humana is seeking a Senior Software Engineer to design, implement, and operate stateful services for real-time decisioning and personalization. You will architect state machines, transactional state stores, and idempotent workflows to guarantee exactly-once processing and robust retries.

Responsibilities include building outbox-based guarantees, ensuring observability, and guiding architecture with cross-functional teams. Remote/hybrid work with travel as needed.

Qualifications

• Bachelor's degree in computer science or related field.
• 6+ years of experience in backend or platform engineering.
• Hands-on expertise with state machine modeling, lifecycle management, transactional state stores, and idempotent API/workflow design.
• Understanding of exactly-once or effectively-once processing and failure modes in distributed environments.
• Proficiency in Java, Kotlin, Go, or Python; experience with AI-assisted development tools.

Responsibilities

• Design, build, and maintain explicit state machines for lifecycles and transitions.
• Architect transactional state stores as single source of truth and ensure high concurrency.
• Implement robust idempotency controls to allow safe retries and at-most-once effects.
• Apply outbox pattern to ensure atomicity of state updates and event publication.
• Design for correctness under concurrency, partitions, failures, and redeployments.
• Leverage AI-powered tools to assist in tests, debugging, and code reviews.
• Ensure observability, tracing, and auditability of state transitions and events.
• Collaborate with platform, data, and quality teams; mentor engineers on distributed systems.

Skills

State machine modeling

Lifecycle management

Transactional state stores

Idempotent API design

Exactly-once processing

Distributed systems

Concurrent programming

Java, Kotlin, Go, Python

Education

Bachelor's degree in computer science or related field

Job description

Humana is seeking a Senior Software Engineer to design, implement, and operate stateful services for real-time decisioning and personalization. You will architect state machines, transactional state stores, and idempotent workflows to guarantee exactly-once processing and robust retries.

Responsibilities include building outbox-based guarantees, ensuring observability, and guiding architecture with cross-functional teams. Remote/hybrid work with travel as needed.