This position is listed on behalf of a partner company, which manages all applications and next steps. Our partner is looking for a Senior Full Stack Analyst/Developer — React and Python based in Brazil. As a Senior Full Stack Developer, you will contribute to the development and continuous evolution of a financial reconciliation platform that supports data ingestion, transformation, processing, and monitoring. You will build end-to-end solutions spanning modern web interfaces, backend APIs, database architecture, and cloud infrastructure. Working closely with business stakeholders, you will investigate production issues, translate complex financial requirements into reliable technical solutions, and improve system performance and scalability. You will also help strengthen data quality, security, traceability, and operational resilience across the platform. This role offers the opportunity to apply modern engineering practices and AI-assisted development in a dynamic financial technology environment where autonomy, technical excellence, and ownership are highly valued.