Senior Backend .NET Engineer

United ITS is expanding its aviation software engineering team.We build high-reliability software systems supporting aviation operations, airspace control, and training environments.We are seeking a Senior Backend .NET Core Engineer to own and architect the integration layer powering real-time operational systems.This role is responsible for backend architecture, system integration, API gateway design, and ensuring reliable communication between control platforms and external engines.Key ResponsibilitiesDesign and implement scalable ASP.NET Core APIsArchitect and implement Microservices-based backend systemsDesign and manage API Gateway layers for secure and scalable service exposureDevelop real-time communication layers (REST, WebSocket, event-driven patterns)Own integration services and command/event processing pipelinesDesign data models and optimize performance using PostgreSQL and PostGISEnsure thread safety, concurrency control, and high-availability architectureCollaborate closely with frontend, desktop, DevOps, and infrastructure teamsRequired Qualifications4+ years of experience with .NET / ASP.NET CoreStrong experience with Microservices architecture and distributed systemsHands-on experience with API Gateway design and implementationStrong expertise in PostgreSQL, including performance tuningExperience working with PostGIS for spatial or geospatial data handling is highly preferredDeep understanding of async programming, multithreading, and concurrency controlExperience designing integration layers or middleware systemsSolid knowledge of API security, authentication (JWT/OAuth2), and system architecture patternsExperience working with mission-critical or real-time systems is highly preferred