Senior Developer (.NET) – Electronic TradingDomain: Fixed Income Electronic TradingLocation: BrazilEmployment Type: (Contract )Job SummarySantander Global Technology is launching a greenfield initiative to enhance its electronic trading platform within SCIB Fixed Income. Working closely with trading teams in London and Spain, the selected candidate will help build a cloud-based trading platform on AWS as part of a multi-year strategic program.This role requires a Senior .NET Developer to design and build high-performance electronic trading and pricing workflows in a small, agile team. The ideal candidate will have strong experience in .NET Core, microservices, cloud architecture, and event-driven systems.Key Responsibilities• Take ownership of end-to-end software delivery ensuring quality and scope expectations are met• Contribute to architecture, technical design, and system documentation• Build scalable electronic trading and pricing services• Work closely with trading business stakeholders and partner technology teams• Design and develop microservices and API-based solutions• Implement best practices for code quality, testing, and CI/CD• Develop high-performance multi-threaded and asynchronous applications• Participate in Agile ceremonies and iterative delivery cycles• Ensure production readiness, observability, and resiliency of servicesRequired Technical Skills• Strong experience with .NET / .NET Core• Solid understanding of Object-Oriented Programming (OOP) principles• Experience building ASP.NET Core Web APIs and RESTful services• Strong experience with multithreading & asynchronous programming• Experience with SQL and NoSQL databases• Hands-on experience with Docker / containerization• Experience building Microservices / Service-Oriented Architectures• Automated testing experience (NUnit, Moq, Cucumber)• Messaging middleware experience (RabbitMQ, TIBCO, SignalR)• CI/CD tools experience (Git, TeamCity, Jenkins or similar)• Strong understanding of Agile / SDLC methodologies