Senior C# / .NET Developer – API Specialist

Description

Job Summary: We are seeking a Senior Developer with experience in designing, developing, and maintaining backend C# and .NET applications, specializing in RESTful APIs and focused on code quality and clean architecture. Key Highlights: 1. Design and development of REST APIs and Web Services with ASP.NET Core 2. Implementation of clean architectures, DDD, SOLID, and design patterns 3. Performance, scalability, and security optimization We seek a Senior Developer with extensive experience in designing, developing, and maintaining enterprise-grade backend applications based on C# and .NET, specializing in building robust, scalable, and secure RESTful APIs. A professional oriented toward code quality, best practices, and clean architecture, with a strong focus on business outcomes. Experience and Specializations More than 3 years in enterprise software development. Design and development of REST APIs and Web Services with ASP.NET Core. Implementation of clean architectures, DDD, SOLID, and design patterns. Integration with external systems and microservices. Performance, scalability, and security optimization. Key Technologies Language: C# Frameworks: .NET, .NET Core, ASP.NET Core APIs: REST, OpenAPI/Swagger, JWT, OAuth2 Architecture: Microservices, Clean Architecture, Hexagonal ORM: Entity Framework / EF Core, Dapper Databases: SQL Server, PostgreSQL, MySQL, MongoDB Testing: NUnit, Moq DevOps: Azure DevOps / GitHub Actions, CI/CD Cloud: Azure (App Services, Functions, Storage, Service Bus) Typical Responsibilities Technical analysis and design of backend solutions. Development of secure, high-performance APIs. Code reviews and mentoring of junior and semi-senior developers. Collaboration with frontend, QA, and DevOps teams. Implementation of unit and integration tests. Technical documentation and production support. Working in agile teams (Scrum / Kanban). Monday to Friday, onsite, 8 AM to 6 PM Indefinite-term contract Work location: KM2 Medellín Highway, 10 minutes from Guadua Bridge Position type: Full-time, indefinite Work location: Onsite employment Salary range: COP 4,500,000 to 5,000,000, depending on experience. -Requirements- Minimum education: University / Professional Degree 3 years of experience Skills: .net, Api, Backend, Database, C#, Frontend Development, Programming Keywords: developer, programmer, senior, sr, dotnet, net, net, specialist, especialista