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

Citi; New York (NY); On-site; USD 140,000 - 180,000; Full time

Job summary

Citi in New York seeks a Senior Front-end Developer to own front-end for a trade processing application, using .NET/C#, React. 5+ years in enterprise web apps is preferred.

You will collaborate with cross-functional teams, migrate legacy components, ensure automated testing, and uphold design standards. Securities domain experience is a plus.

Qualifications

• 5+ years of UI or full-stack development with front-end focus.
• Proficiency in .NET and C#, enterprise-grade apps.
• Strong React experience; HTML5, CSS3, JS mastery.
• Experience with automated testing practices.

Responsibilities

• Design and deliver front-end web applications for a trade processing platform.
• Own the UI development lifecycle from requirements to deployment.
• Migrate legacy Citi UI to React-based HTML5 interfaces.
• Ensure automated testing and code quality across all work.

Skills

UI / front-end development

NET / C#

React

HTML5 / CSS3 / JavaScript

Automated testing

TypeScript

Education

Bachelor's degree in Computer Science, Engineering, related field or equivalent professional experience

Tools

Angular

REST APIs

JSON/XML

Job description

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

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.
• Track business unit performance against IT plans and service level agreements, identifying and escalating gaps as needed.
• Define and uphold operating standards and development processes across the team.
• Act as a subject matter expert and mentor to junior analysts and other team members.
• Assess risk in technology and business decisions, ensuring compliance with applicable laws, regulations, and Citigroup policies.
• Operate with a high degree of autonomy and independent judgment while supporting senior stakeholders across the organization.

Qualifications

• 5+ years' experience in UI or full‑stack development, with a strong focus on front‑end engineering.
• Mandatory proficiency in .NET and C#, with demonstrated experience building or supporting enterprise‑grade applications.
• Proficiency in React; experience with Angular is a plus, as the broader team maintains components in both frameworks.
• Solid command of HTML5, CSS3, and JavaScript as core front‑end technologies.
• Experience with test frameworks and a commitment to fully automated testing practices.
• Knowledge of TypeScript is preferred.
• Experience with JSON/XML data formats and REST API‑based web service integrations.
• Prior experience in financial services, capital markets, or trade processing applications is a significant advantage.
• Familiarity with Security Financing Transactions, Fixed Income, or similar capital markets instruments is beneficial.
• Strong self‑motivation, attention to detail, and the ability to operate independently with limited supervision.

Education

• Bachelor's degree in Computer Science, Engineering, related field or equivalent professional experience.

This job description provides a high-level review of the types of work performed. Other job-related duties may be assigned as required.

This job opening is for an existing job vacancy.

Citi is an equal opportunity employer, and qualified candidates will receive consideration without regard to their race, color, religion, sex, sexual orientation, gender identity, national origin, disability, status as a protected veteran, or any other characteristic protected by law.

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