As a Senior .
NET Backend Developer, you will drive architectural decisions for our flagship product's server-side platform.
You will work closely with Frontend and UX/UI teams to design and deliver robust APIs, ensure scalability, and maintain high performance and reliability.
Freelance or permanent.
Responsibilities Design, develop, and maintain backend services and RESTful APIs using .
NET Core Drive backend architecture decisions (modularity, scalability, reliability, observability) Build reusable backend components, shared libraries, and utilities for future use Translate product requirements into clean, maintainable, and well-tested code Optimize services for performance, throughput , and low latency under high load Ensure secure data handling, authentication/authorization, and best practices Implement logging, metrics,



and tracing using Azure-friendly observability tooling Collaborate with database and platform teams to design efficient data models and integrations Requirements 3+ years of experience in backend development 1+years of experience with Claude Code and/or OpenCode 50% remote, 50% in Madrid Strong proficiency in C# and the .
NET ecosystem (ASP.NET Core, DI, middleware) Solid understanding of API design , versioning, and documentation (OpenAPI/Swagger) Experience with data access patterns and libraries (e.G., Entity Framework Core, Dapper) Knowledge of SQL and/or NoSQL databases and performance tuning Experience with testing practices (unit/integration tests) and CI/CD workflows #J-*****-Ljbffr

📌 Ingeniero Senior .Net (Madrid)
🏢 RuiderIA
📍 Madrid