Senior Front-end Developer (.NET/C#)

About Citi: Citi, the leading global bank, has approximately 200 million customer accounts and does business in more than 160 countries and jurisdictions. Citi provides consumers, corporations, governments, and institutions with a broad range of financial products and services, including consumer banking and credit, corporate and investment banking, securities brokerage, transaction services, and wealth management. As a bank with a brain and a soul, Citi creates economic value that is systemically responsible and in our clients’ best interests. As a financial institution that touches every region of the world and every sector that shapes your daily life, our Operations & Technology teams are charged with a mission that rivals any large tech company. Our technology solutions are the foundations of everything we do from keeping the bank safe, managing global resources, and providing the technical tools our workers need to be successful to designing our digital architecture and ensuring our platforms provide a first-class customer experience. We reimagine client and partner experiences to deliver excellence through secure, reliable, and efficient services. Our commitment to diversity includes a workforce that represents the clients we serve from all walks of life, backgrounds, and origins. We foster an environment where the best people want to work. We value and demand respect for others, promote individuals based on merit, and ensure opportunities for personal development are widely available to all. Ideal candidates are innovators with well-rounded backgrounds who bring their authentic selves to work and complement our culture of delivering results with pride. If you are a problem solver who seeks passion in your work, come join us. We’ll enable growth and progress together. The Role: We are seeking a Senior Front-end Developer to join the Markets Technology division where they will take primary ownership of the front-end development of a trade processing application supporting Security Financing Transactions across Fixed Income, Markets Treasury, and Finance business lines. This is a full-stack-capable role with a heavy front-end emphasis, requiring deep proficiency in .NET/C# alongside modern UI frameworks particularly React. The ideal candidate will bring 5+ years of hands-on experience building and modernizing enterprise-grade web applications, with a strong preference for those who have worked in financial services or capital markets environments. You will operate as a subject matter expert collaborating closely with cross-functional technology teams and senior stakeholders to deliver scalable, compliant, and well-tested UI solutions. Responsibilities * Design and deliver front-end web applications for a trade processing platform supporting Security Financing Transactions across Fixed Income and Markets Treasury business lines. * Take primary ownership of the UI development lifecycle, from requirements gathering through implementation and post-deployment support. * Migrate and transform legacy Citi UI components into React-based HTML5 interfaces using standard Citi design components. * Ensure all front-end development is delivered with fully automated testing and adherence to good design standards throughout. * Monitor and control all phases of the development process, including analysis, design, construction, testing, and implementation. * Conduct feasibility studies, produce time and cost estimates, and contribute to IT planning activities relevant to the application. * Analyze complex technology problems, evaluate business and system processes against industry standards, and provide sound technical recommendations. * Recommend and implement security measures as part of post-implementation reviews to ensure successful system design and functionality. * Consult with business users, clients, and cross-functional technology teams to advise on advanced programming solutions and resolve technical issues. *...