We are looking for a **Mid-Level Systems Developer (Full Stack)** to work on the development, evolution, and maintenance of medium- and high-complexity web applications within the **.NET** ecosystem. The position will be part of **agile squads**, collaborating closely with Technology and Product professionals, actively contributing to scalable, secure, and business-aligned solutions. We value sound engineering practices, technical excellence, and continuous knowledge sharing across teams. We operate in a continuous improvement-oriented environment, focused on efficiency, technical accountability, and value delivery. **Responsibilities and Duties** **Responsibilities:** * Build and evolve **REST APIs** and backend services using **ASP.NET Core** * Apply principles of **Clean Architecture, SOLID, and DDD** * Model and access data using **Entity Framework Core** and **Azure SQL Database**, ensuring performance and integrity * Implement integrations between **microservices and external systems** (messaging, WebHooks, OAuth2/OIDC) * Support the development of user interfaces (**Razor/Blazor or SPA**), ensuring usability and responsiveness * Actively participate in **code reviews**, proposing technical improvements * Support application monitoring (logs, metrics, tracing, telemetry) * Contribute to the continuous improvement of **CI/CD processes and pipelines** **Expected Experience:** * Prior experience in **web system development** * Experience working in **agile and collaborative environments** * Experience with medium- and high-complexity systems **Requirements and Qualifications** * **3 to 5 years** of experience with **C# / .NET Core** * Proficiency in **Entity Framework Core**, **LINQ**, and **SQL** * Hands-on experience with **Azure SQL Server**, including performance and security best practices * Knowledge of **automated testing** (xUnit and/or MSTest) * Familiarity with **DevOps practices** (CI/CD, GitFlow) * Strong communication, collaboration skills, and experience working in **agile squads** * Completed undergraduate degree in **Computer Science, Software Engineering, or related fields** **Additional Information** **Work Model:** * Hybrid (**4 days on-site + 1 day remote per week**) * Employment type: **Individual Contractor (PJ)** * On-site presence is valued for learning, team interaction, and technical mentorship **Work Locations:** * **Porto Alegre:** Praia de Belas * **Rio de Janeiro:** Barra da Tijuca * **São Paulo:** Cidade Monções At Tecsa Group, our purpose is simple: care for people to build a healthier future. We know health is an ongoing journey, which is why we create technology solutions that significantly and sustainably impact people’s lives. Every project we develop is designed to deliver quality of life, longevity, and well-being—not only for our clients but also for their families and communities. We aim to be the driving force transforming healthcare in Brazil and beyond—making it accessible, innovative, and human-centered.