Back-end Developer | .NET & Azure

Description

Job Summary: We are seeking a Back-end Developer to drive the evolution, modernization, and maintenance of a SaaS platform, delivering impact to end users and business operations, working with .NET Core, C#, and Azure. Key Highlights: 1. SaaS platform evolution and modernization 2. Development in critical environments using .NET Core, C#, and Azure 3. Contribution to product architecture and engineering We are looking for a Back-end Developer to work on the evolution, modernization, and maintenance of a production SaaS platform with high impact on end users and business operations. This person will primarily work with .NET Core, .NET 8, C#, SQL Server, and Azure, directly contributing to the evolution of APIs, integrations, services, performance, security, observability, and platform stability. We seek a technically proficient, analytical, and pragmatic individual who enjoys solving real-world problems, operating in critical environments, and contributing to the sustainable evolution of product architecture and engineering. **Responsibilities and Duties** * Develop and maintain APIs, services, and integrations using C#, .NET Core, and .NET 8; * Drive technical evolution of production SaaS systems; * Build secure, high-performance, well-documented, and scalable APIs; * Work with SQL Server, including data modeling, queries, stored procedures, indexing, and performance optimization; * Support diagnosis and resolution of production issues; * Contribute to improvements in observability, logging, metrics, and traceability; * Participate in code reviews, technical discussions, and definition of development standards; * Support legacy modernization initiatives and technical debt reduction; * Work with Azure services such as App Service, Azure SQL, Application Insights, Azure Functions, and Key Vault; * Collaborate with Front-end, Mobile, Product, QA, and DevOps teams; * Contribute to CI/CD pipelines, automated deployment, and continuous improvement of delivery quality; * Support creation of automated tests and engineering practices to reduce regressions. **Requirements and Qualifications** * Solid back-end development experience; * Experience with C# and .NET Core; * Knowledge of .NET 8; * Experience building REST APIs; * Experience with SQL Server; * Knowledge of database performance tuning, queries, indexing, and troubleshooting; * Experience with Azure cloud; * Knowledge of Git and version control best practices; * Familiarity with API security, authentication, and authorization; * Ability to operate in critical production systems; * Strong communication skills and ability to collaborate effectively with Product and Engineering teams. **Nice-to-have** ----------------------- * Knowledge of Vue.js; * Knowledge of React or React Native; * Knowledge of GCP (Cloud Run, Cloud SQL, Pub/Sub, Cloud Storage, or similar); * Knowledge of Docker and containers; * Experience with Azure DevOps or GitHub Actions; * Experience with Application Insights, Azure Monitor, or similar tools; * Experience with automated testing; * Knowledge of messaging, queues, and asynchronous processing; * Experience with modular architecture, microservices, or distributed systems; * Experience with SaaS platforms or high-volume transactional systems; * Knowledge of LGPD, security, and auditing. **Additional Information** * Contract type: PJ (individual contractor) * Work model: Hybrid — 3 days on-site and 2 days remote per week. Work location: * São Paulo (SP) \- Vila Mariana 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.