Proximity Health

The Opportunity Proximity is seeking a Senior Staff Software Engineer / Engineering Lead to drive the architectural evolution of our cloud-native platform. This is a high-leverage player-coach role: you will define engineering standards, architect high-volume distributed systems, and lead a US-based team of engineers through complex technical challenges. You’re not just a lead — you’re a technical authority. You understand what happens to a database index when a table hits a billion rows. You can diagnose why a distributed transaction failed before you even open the logs because you helped design the system and its observability. You operate with the urgency to stabilize production systems, and the long-term perspective to build a platform that scales. Core Responsibilities 1. Architectural Strategy & Cloud Leadership - Architect and implement scalable microservices using .NET Aspire and Azure Container Apps, ensuring reliable service discovery, resiliency, and operational simplicity. - Design hybrid cloud data strategies, managing complex ETL pipelines between AWS S3 and Azure Data Factory that handle terabytes of data with automated retries, resilience and binary copy resumption. - Define the "Golden Path" for development, utilizing YARP as a strategic Backend-for-Frontend (BFF) to manage traffic routing, protocol upgrades, and legacy system strangulation. 2. High-Volume Data Engineering - Own the database architecture for high-load systems. Implement declarative partitioning (range/hash) strategies to maintain sub-millisecond query performance on datasets exceeding 1 billion rows. - Optimize Entity Framework Core and SQL queries to ensure efficient partition pruning, preventing I/O bottlenecks. - Manage the lifecycle of heavy data loads, ensuring zero-downtime migrations and non-blocking maintenance operations (e.g., VACUUM/ANALYZE). 3. Distributed Systems & Reliability - Implement eventual consistency patterns using MassTransit Sagas (state machines) to orchestrate complex, long-running business transactions across microservices. - Enforce the Transactional Outbox pattern to guarantee message reliability, idempotency, and correctness in an event-driven architecture. - Secure the infrastructure using Azure Private Link and VNet integration, ensuring critical data stores have no public exposure. 4. Observability & Operational Excellence - Build a world-class observability stack using OpenTelemetry (OTel), Azure Monitor, and Azure Managed Grafana. - Define Service Level Objectives (SLOs) and create dashboards that visualize saturation, latency, and error rates to proactively identify bottlenecks. - Lead the team through root-cause analysis and incident reviews, fostering a blameless culture that prioritizes systemic improvement over individual fault. Qualifications - Experience: 10+ years of software engineering experience, including 3+ years in a Lead, Staff, Principal, or architecture-focused role. - Tech Stack: Mastery of C# /.NET 8+, Azure (Container Apps, SQL, Service Bus, ADF), and AWS (S3 integration). - Heavy Load Expertise: Proven track record of scaling databases (PostgreSQL/SQL Server) to billions of rows. You can explain how you diagnosed and solved locking, bloat, or performance issues at scale. - Integration Mastery: Experience with complex backend integrations. Knowledge of EDI standards (X12, NCPDP D.0) or healthcare claims processing is a major plus. - Leadership Style: Demonstrated ability to lead remote teams, set best practices (RFCs, Code Review Standards), and mentor senior engineers. - Work Authorization: Must be currently authorized to work in the United States without need for future sponsorship. Compensation & Benefits - Benefits: Comprehensive Medical, Dental, and Vision, 100% premium for employees and 25% coverage for dependents - Culture: A focus on technical excellence, where urgency means disciplined execution — and architecture is treated as a competitive advantage. Why Proximity - Build technology that strengthens access to care across the U.S. healthcare system. - Shape the architecture of a platform evolving from automation to intelligence. - Work alongside a data-focused, mission-driven team redefining how 340B programs operate. - Be part of an organization with a clear, unified technical vision and high expectations for engineering excellence.