Senior Software Engineer

Join Our Caring CommunityWe are seeking an accomplished Senior Software Engineer to design, implement, and operate mission-critical stateful services that form the backbone of real-time, automated decisioning and personalization platforms. These systems are responsible for maintaining authoritative state, orchestrating lifecycle transitions, and ensuring reliable downstream effects—often in high-concurrency, low-latency environments. This position is ideal for engineers with a strong grasp of state machines, idempotency, distributed systems, and "exactly-once" execution semantics. You will also employ advanced AI-assisted and agentic engineering tools to drive correctness, velocity, resilience, and scalability.Key ResponsibilitiesState Machine Architecture & ImplementationDesign, build, and maintain explicit state machines governing:Lifecycle transitions (e.g., open ? in progress ? completed ? suppressed)Validation of permissible transitionsTime-based and event-driven changesEnsure state machines are:Clearly modeled and not hidden in code logicDeterministic, reproducible, and auditableEasily understood and testableRobust against illegal or duplicate transitions through comprehensive validationTransactional State Memory & Exactly-Once ProcessingArchitect and manage transactional state stores serving as the single source of truthSupport safe, high-concurrency read/write operationsUphold system invariants across partial failures and recovery scenariosImplement robust idempotency controls so:Requests can be safely retriedCommands execute at most onceDuplicate events do not compromise state integrityDevelop APIs and workflows resilient to retries, restarts, and replay eventsReliable Side Effects via Outbox PatternEmploy the outbox pattern to guarantee atomicity of state updates and event publicationPrevent loss or duplication of side effectsMaintain clear separation between state mutation and downstream event deliveryFacilitate replay, backfill, and recovery operations without breaching state guaranteesIntegrate seamlessly with messaging and streaming platforms, ensuring fault toleranceDistributed Systems & Concurrency ManagementDesign for correctness under concurrent updates, network partitions, partial failures, and service redeploymentsApply expertise in:Idempotency keysOptimistic and pessimistic locking strategiesEvent ordering and causalityBalance rigorous correctness with performance and latency requirementsAI-Assisted & Agentic Engineering PracticesLeverage AI-powered and agentic tools to:Automatically generate and validate state transition testsProbe edge cases and concurrency challengesAssist in code reviews, refactoring, and documentationAccelerate debugging, incident analysis, and root cause discoveryUse AI responsibly to enhance productivity while maintaining clarity and system integrityObservability, Auditability & TrustEngineer services with robust observability through:Structured logging, metrics, and alertingDistributed tracingEnsure all state transitions and emitted events are:Fully traceable and reproducibleAuditable for compliance and investigative needsCollaboration & Technical LeadershipPartner with platform, data, and quality engineering teams to assure end-to-end reliabilityParticipate in architecture and design reviews to elevate system quality standardsMentor and guide engineers on best practices for safe, reliable, and maintainable distributed systemsUse Your Skills to Make an ImpactRequired QualificationsBachelor's degree in computer science or related field6+ years of experience in backend or platform engineeringDemonstrated hands-on expertise with:State machine modeling and lifecycle managementTransactional state storesIdempotent API and workflow designIn-depth understanding of:Exactly-once or effectively once processingFailure modes in distributed environmentsProficiency in one or more contemporary languages (e.g., Java, Kotlin, Go, Python)Experience with AI-assisted development tools for productivity and code qualityPreferred QualificationsExperience with outbox, transactional messaging, or event sourcing patternsFamiliarity with low-latency, high-throughput architecturesOperational experience in systems requiring strict auditability and correctnessBackground in regulated or mission-critical domainsSuccess IndicatorsState transitions are precise, deterministic, and resilient to retriesSide effects reliably occur exactly once, even during failures or replaysSystems recover gracefully from crashes and redeploymentsAI-driven tooling decreases defect rates and expedites debuggingThe state layer is trusted as the definitive source of truth across engineering teamsWhy This Role is CriticalIn contemporary automated platforms, correctness and reliability hinge on the integrity of state, not just requests. This role ensures that every state transition and side effect is executed once—and only once—providing a solid foundation for trust, reliability, compliance, and scalability throughout the system.Qualified candidates are required to currently live in, or be willing to move to, a commutable distance for a hybrid (~3 days in-office) work arrangementLocation options are currently:Washington, D.C. metropolitan areaLouisville, KY metropolitan areaDenver, CO metropolitan areaDallas, TX metropolitan areaFt. Lauderdale, FL metropolitan areaWork Style: Remote/Hybrid.Occasional travel to Humana's offices for training or meetings may be required.Work Hours: Typical business hours are Monday-Friday, 8 hours/day, 5 days/week-- some flexibility might be possible, depending on business needs.Very minimal travel might be required for training, meetings, and/or conferencesInterview FormatAs part of our hiring process, we will be using on-demand technology provided by Hire Vue, a third-party vendor. This technology provides our team of recruiters and hiring managers with an enhanced method for decision-making through on-demand candidate assessments.If you are selected to move forward from your application prescreen, you will receive correspondence inviting you to participate in an on-demand assessment with pre-determined questions. You should anticipate the assessment to take approximately 10-15 minutes.Your on-demand assessment will be reviewed, and you will subsequently be informed if you will be moving forward to next round of interviews.SSN Task via WorkdayShould you be extended a formal employment offer you will receive a request to enter your SSN into our Workday system to scan for duplicate profiles.Work at Home Requirements: To ensure Home or Hybrid Home/Office employees' ability to work effectively, the self-provided internet service of Home or Hybrid Home/Office employees must meet the following criteria: At minimum, a download speed of 25 Mbps and an upload speed of 10 Mbps is required;