Senior Developer - Backend

Digital Construction Support (DCS, *Digitale Baubegleitung*) is the central platform supporting the digital management and documentation of fiber construction sites in Germany. The platform helps construction supervisors and partners work more efficiently, improves quality during construction, and enables greater automation of documentation and billing processes. You will join a cross-functional team responsible for developing and operating a distributed ecosystem of backend services and integrations. Your responsibilities - Own backend services throughout their lifecycle: design, implementation, testing, deployment, operation, and continuous improvement. - Translate product and business requirements into maintainable technical designs, clearly communicating risks and trade-offs to Product Owners, architects, and other engineering teams. - Design and implement secure, versioned REST APIs and maintain their OpenAPI contracts. - Develop primarily with Node.js and TypeScript, using PostgreSQL/PostGIS for relational and geospatial data. - Design database schemas, transactions, indexes, and backward-compatible migrations; analyze and optimize complex SQL queries. - Build reliable integrations with Kafka, AWS S3, GeoServer, and internal or external APIs. - Implement automated unit and integration tests and contribute to API-contract, end-to-end, and performance testing. - Build observability into services through structured logging, metrics, tracing, health checks, and actionable alerting. - Diagnose defects and production incidents, participate in root-cause analysis, and implement preventive improvements. - Contribute to CI/CD pipelines and operate containerized services on OpenShift/Kubernetes. - Review merge requests, mentor engineers, and promote pragmatic engineering and quality standards. - Maintain API documentation, architectural decisions, and operational runbooks. - Use AI-assisted development tools responsibly, retaining full accountability for the correctness