Sr. Software Developer - Application Migration & Modernization

This position is listed on behalf of a partner company, which manages all applications and next steps. Our partner is looking for a Sr. Software Developer – Application Migration & Modernization based in Brazil.

We are looking for a senior software developer to support application migration and modernization initiatives, helping improve the performance, maintainability, and scalability of existing business systems. In this role, you will work with established Microsoft technologies and database platforms to modernize legacy applications while preserving critical functionality. You will contribute to backend development, application architecture, database optimization, and integration solutions across enterprise environments. The position also involves supporting cloud infrastructure and implementing reliable deployment practices through CI/CD pipelines. You will have opportunities to leverage AI-assisted development tools and agentic workflows to improve engineering efficiency. This remote opportunity is suited to an experienced developer who combines strong technical expertise with a practical, modernization-focused mindset.

Accountabilities

• Maintain, enhance, and modernize existing applications built with C#, .NET Framework 4.8, ASP.NET MVC, ASP.NET Web Forms, and Web API.
• Support the migration of legacy applications toward more maintainable, scalable, and modern architectures while ensuring business continuity.
• Develop, integrate, and maintain application services and APIs, including systems that use Windows Communication Foundation (WCF).
• Work with Microsoft Internet Information Services (IIS) to support application hosting, configuration, deployment, and troubleshooting.
• Design, maintain, and optimize database solutions using Oracle PL/SQL, PostgreSQL, PL/pgSQL, and SQL.
• Analyze existing codebases and database structures to identify opportunities for performance improvements, simplification, and modernization.
• Use Git and CI/CD practices to manage source code, streamline deployments, and maintain reliable development workflows.
• Contribute to cloud-based application environments using AWS services, including EC2 and RDS.
• Apply AI-assisted development tools and agentic workflows where appropriate to accelerate implementation, code analysis, testing, and modernization activities.
• Collaborate with technical stakeholders to troubleshoot issues, validate solutions, and deliver reliable application improvements.

Requirements

• Strong professional experience in software development, particularly maintaining, enhancing, and modernizing enterprise applications.
• Proficiency in C# and the .NET Framework 4.8, with practical experience in ASP.NET MVC, Web API, and Web Forms.
• Familiarity with WCF and IIS in application development, integration, hosting, and maintenance contexts.
• Strong database development skills, including Oracle PL/SQL, PostgreSQL, PL/pgSQL, and SQL query optimization.
• Experience using Git for version control and working with CI/CD pipelines to support automated build and deployment processes.
• Knowledge of AWS infrastructure, particularly EC2 and RDS, and an understanding of application deployment in cloud environments.
• Ability to analyze legacy systems, understand existing business logic, and implement improvements without compromising critical functionality.
• Familiarity with AI-assisted software development tools and agentic workflows, or the ability to adopt these tools effectively.
• Strong analytical and troubleshooting skills, attention to detail, and a commitment to producing maintainable, reliable code.
• Effective communication and collaboration skills, along with the ability to work independently in a remote environment.
• Sufficient English proficiency to communicate about technical requirements, collaborate with stakeholders, and document development work.

Benefits

• Remote work: Opportunity to work remotely from Brazil.
• Senior-level technical ownership: Contribute to application migration, modernization, and continuous improvement initiatives.
• Enterprise technology experience: Work with established Microsoft technologies, relational databases, and cloud infrastructure.
• Modern development practices: Apply CI/CD workflows and AI-assisted engineering tools to improve productivity and software quality.
• Technical development: Deepen your expertise in legacy application modernization, backend engineering, database systems, and AWS.
• Contractor opportunity: The application process requests salary expectations in US dollars, indicating a contractor-oriented compensation discussion.