Senior UI Developer (.NET/React)

📍 Job Overview

Job Title: Senior UI Developer (.NET/React)

Company: Citi

Location: Toronto, Ontario, Canada

Job Type: Full-time

Category: Applications Development / Front-End Engineering

Date Posted: 2026-06-11

Experience Level: 5-10 Years

Remote Status: Hybrid

🚀 Role Summary

• This Senior UI Developer role focuses on transforming existing UI elements into modern React-based HTML5 components within Citi's global finance technology infrastructure.

• The position involves designing and delivering front-end web applications, solving complex technical challenges, and contributing to the continuous improvement of user interfaces.

• You will be responsible for ensuring fully automated testing, adherence to Citi's standard component library, and maintaining high design quality throughout the development lifecycle.

• This role offers an opportunity to influence economies, drive innovation in financial services technology, and collaborate with a global team at a leading financial institution.

📝 Enhancement Note: The job title and description clearly indicate a focus on front-end development, specifically within a financial services context. While the initial input doesn't explicitly mention "Revenue Operations" or "Sales Operations," the emphasis on building robust, scalable, and well-tested user interfaces for a global financial institution implies a strong connection to operational efficiency and user experience that directly impacts business functions. The "Applications Development" and "Finance Technology" taxonomies further support this interpretation.

📈 Primary Responsibilities

• Design and deliver robust, scalable, and user-friendly front-end web applications based on detailed business requirements and user stories.

• Transform existing UI elements and components into modern React-based HTML5 structures, leveraging Citi's established component library for consistency and efficiency.

• Implement comprehensive automated testing strategies (unit, integration, end-to-end) to ensure code quality, reliability, and maintainability.

• Collaborate closely with product managers, UX/UI designers, and back-end developers to translate complex requirements into elegant and functional user interfaces.

• Conduct thorough feasibility studies, time estimations, and risk assessments for proposed UI development projects, aligning with IT business plans and SLAs.

• Analyze, design, construct, test, and implement new or revised applications systems and programs, ensuring they meet specific business needs and user area requirements.

• Monitor and control all phases of the development process, providing ongoing user and operational support for applications to business users.

• Act as a Subject Matter Expert (SME) for UI development best practices, providing guidance and mentorship to junior developers and stakeholders.

• Assess and manage risks associated with business decisions, demonstrating strong consideration for the firm's reputation, client trust, and asset protection.

• Ensure adherence to applicable laws, rules, regulations, and Citi's policies, applying sound ethical judgment in all personal behaviors, conduct, and business practices.

• Escalate, manage, and report control issues with transparency, contributing to a culture of operational integrity and compliance.

📝 Enhancement Note: The responsibilities listed are typical for a senior front-end developer within a large enterprise, especially in a regulated industry like finance. The emphasis on risk assessment, compliance, and operational integrity points to the critical nature of this role in a global financial services organization. The transformation of existing UI to React suggests a modernization initiative, requiring strong technical leadership and a focus on efficient, well-documented processes.

🎓 Skills & Qualifications

Education:

• Bachelor’s degree in Computer Science, Information Technology, Engineering, or a related field, or equivalent practical experience. Experience:

• 5-10 years of relevant professional experience in Windows and Web UI Development.

• Proven track record of delivering complex front-end applications in a corporate or enterprise environment. Required Skills:

• .NET/C# Proficiency: Deep understanding and practical experience with the .NET framework and C# for back-end services or integration layers, if applicable to UI development context.

• React Expertise: Strong command of React.js for building dynamic and interactive user interfaces, including component-based architecture, state management (e.g., Redux, Context API), and hooks.

• HTML5 & CSS3: Solid understanding of semantic HTML5 and modern CSS3 techniques for responsive and accessible web design.

• JavaScript (ES6+): Proficient in modern JavaScript (ECMAScript 6 and later) for client-side logic and interactivity.

• Automated Testing Frameworks: Experience with front-end testing frameworks (e.g., Jest, React Testing Library, Cypress) for building reliable and maintainable code.

• Front-end Design Principles: Ability to translate design mockups and wireframes into high-quality, functional code, with a strong eye for detail and user experience.

Preferred Skills:

• TypeScript: Familiarity and practical experience with TypeScript for enhanced type safety and code maintainability in large-scale applications.

• JSON/XML: Experience working with JSON and XML data formats for data interchange.

• REST API Integrations: Proven ability to integrate with RESTful APIs and web services to fetch and manipulate data.

• Version Control: Proficiency with Git and collaborative development workflows.

• Agile Methodologies: Experience working in Agile/Scrum development environments.

📝 Enhancement Note: The required skills are well-defined and directly align with the role's focus on modern front-end development. The inclusion of .NET/C# alongside React suggests a potential need for interaction with .NET-based back-end systems or a hybrid development environment. The "5-10 Years" experience level is appropriate for a Senior role.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• Demonstrate React Application Development: Showcase at least two significant projects built using React, highlighting complex UI components, state management, and integration with APIs.

• Showcase .NET/C# Integration (if applicable): If any portfolio projects involved interacting with .NET back-ends or services, clearly articulate your role and the integration points.

• Process Optimization Examples: Present case studies or project descriptions that illustrate how you improved UI performance, developer efficiency, or user experience through specific design or coding choices.

• Automated Testing Implementation: Provide evidence of automated testing within your projects, detailing the frameworks used and the scope of testing coverage achieved.

• Code Quality & Standards: Ensure your portfolio code is well-structured, commented, and adheres to modern coding standards, demonstrating a commitment to maintainable and readable code.

Process Documentation:

• Workflow Design: Be prepared to discuss your approach to designing user workflows and translating them into intuitive UI interactions.

• Implementation & Automation: Describe your methods for implementing new features and your strategies for automating repetitive development tasks or testing procedures.

• Measurement & Performance Analysis: Explain how you measure the success of UI implementations, focusing on metrics such as load times, user engagement, and error rates.

📝 Enhancement Note: For a senior developer role, a portfolio is crucial. The emphasis here is on demonstrating practical application of React, .NET integration, process improvement, and automated testing, which are key to success in this role and highly valued in enterprise development.

💵 Compensation & Benefits

Salary Range: $94,300.00 - $141,500.00 CAD per year

Benefits:

• Comprehensive Health Coverage: Medical, dental, and vision insurance plans.

• Retirement Savings Plan: Access to a competitive employer-sponsored retirement savings program (e.g., RRSP matching in Canada).

• Paid Time Off: Generous vacation days, sick leave, and public holidays.

• Professional Development: Opportunities for training, certifications, and attending industry conferences.

• Employee Assistance Program: Confidential counseling and support services.

• Potential Hybrid Work Model: Flexibility to work from home and in the office, promoting work-life balance.

• Employee Stock Purchase Plan: Opportunity to invest in Citi stock.

• Life and Disability Insurance: Protection for employees and their families.

Working Hours:

• Standard full-time hours, typically 40 hours per week, with potential for flexibility based on project needs and team agreements.

📝 Enhancement Note: The provided salary range is specific to Toronto, Canada, and aligns with industry benchmarks for a Senior UI Developer. The benefits listed are standard for a large financial institution like Citi and are highly attractive to experienced professionals. The mention of "potential hybrid work opportunities" aligns with the AI-derived "Hybrid" work arrangement.

🎯 Team & Company Context

🏢 Company Culture

Industry: Financial Services / Global Banking. Citi operates at the forefront of global finance, handling trillions of dollars daily and conducting business in over 180 countries. This context means a strong emphasis on security, compliance, stability, and innovation.

Company Size: Large Enterprise (over 230,000 employees globally). This size implies a structured environment with established processes, extensive resources, and opportunities for specialization and career progression across various departments and geographies.

Founded: The company has a long and rich history, tracing its origins back to 1812. This longevity signifies stability, deep market understanding, and a continuous evolution to adapt to changing economic landscapes and technological advancements.

Team Structure:

• Global Technology Organization: The role is part of Citi's extensive Technology division, which is crucial for supporting and innovating within the financial services sector.

• Applications Development Family: This specific role falls under the Applications Development job family, indicating a focus on building and maintaining software solutions.

• Cross-functional Collaboration: Expect to work closely with product management, UX/UI design, quality assurance, and various business units to deliver cohesive and effective solutions. The team likely includes developers with diverse specializations (e.g., back-end, DevOps, data engineering).

Methodology:

• Agile Development: Citi widely adopts Agile methodologies (Scrum, Kanban) for software development, emphasizing iterative progress, collaboration, and adaptability.

• DevOps Practices: A strong focus on integrating development and operations for faster, more reliable software delivery, including CI/CD pipelines and automated testing.

• Data-Driven Decision Making: Leveraging data analytics to inform development priorities, assess performance, and drive continuous improvement across applications and processes.

Company Website: https://www.citi.com/

📝 Enhancement Note: Understanding Citi's scale, industry, and history is key. For an operations-minded candidate, this means preparing for a structured, compliance-driven environment where robust processes and reliable technology are paramount. The emphasis on "global finance" and "trillions of dollars" underscores the criticality of this role.

📈 Career & Growth Analysis

Operations Career Level: Senior Front-End Developer. This level signifies a high degree of technical expertise, problem-solving capability, and the ability to mentor others. In a large organization like Citi, this role often involves leading technical aspects of projects and contributing to architectural decisions within the UI domain.

Reporting Structure: Typically, a Senior UI Developer would report to a Development Manager, Engineering Lead, or potentially a Director within the Applications Development group. They would work within a project team structure, collaborating with peers and cross-functional stakeholders.

Operations Impact: While this role is primarily technical, its impact on operations is significant. By developing modern, efficient, and reliable user interfaces for financial applications, this role directly contributes to:

• Improved User Efficiency: Streamlining complex financial tasks for internal users (e.g., traders, analysts, customer service) leading to faster processing times and reduced errors.

• Enhanced Customer Experience: For customer-facing applications, a well-designed UI can improve engagement, satisfaction, and trust.

• System Stability and Reliability: Through robust coding and automated testing, the developer helps ensure the uptime and integrity of critical financial systems.

• Reduced Operational Costs: Efficient UIs can minimize training needs and reduce the number of support tickets related to usability issues.

Growth Opportunities:

• Technical Specialization: Deepen expertise in React, front-end architecture, performance optimization, or explore adjacent areas like UI automation testing.

• Team Leadership: Progress to roles like Tech Lead, guiding development teams, and influencing technical direction.

• Architectural Roles: Move into UI Architect or Software Architect positions, designing complex systems and setting technical standards.

• Management Track: Transition into Engineering Management, leading teams and focusing on people and project delivery.

• Cross-Functional Roles: Explore opportunities in product management, program management, or even business analysis within the technology division.

📝 Enhancement Note: This section translates the technical role into an operations context, highlighting how UI development impacts business efficiency, cost reduction, and overall operational effectiveness within a financial institution. The growth paths are typical for senior technical roles in large enterprises.

🌐 Work Environment

Office Type: The job posting mentions "48 YONGE ST - WEWORK TORONTO" and "Potential hybrid work opportunities," indicating a modern, flexible work environment. This suggests a combination of co-working space access and remote work. The WeWork environment often fosters collaboration and networking.

Office Location(s): Toronto, Ontario, Canada. The specific WeWork location provides a central urban workspace.

Workspace Context:

• Collaborative Spaces: WeWork locations are designed with open spaces, meeting rooms, and common areas that encourage interaction and spontaneous collaboration among colleagues and potentially with individuals from other companies.

• Technology Infrastructure: Access to reliable internet, meeting room technology, and potentially shared office resources. The core development will likely occur on personal or company-issued laptops, utilizing cloud-based development tools and environments.

• Team Interaction: While hybrid, there will be structured opportunities for in-person team meetings, brainstorming sessions, and project kick-offs, alongside regular virtual communication channels (e.g., Slack, Teams, video conferencing).

Work Schedule:

• The role is full-time (40 hours/week). The hybrid arrangement allows for flexibility in structuring the work week, balancing remote productivity with in-office collaboration as needed by the team and project requirements.

📝 Enhancement Note: The mention of WeWork and hybrid work suggests a modern, dynamic environment that values flexibility and collaboration. For an operations professional, this means adapting to a blended work model and leveraging technology for effective communication and productivity.

📄 Application & Portfolio Review Process

Interview Process:

• Initial Screening: HR or recruiter call to assess basic qualifications, cultural fit, and alignment with the role's core requirements.

• Technical Assessment (Online/Take-home): A coding challenge focused on React,

JavaScript, and potentially .NET/C# concepts, or a take-home project to evaluate practical skills.

• Technical Interviews (2-3 rounds): In-depth discussions with engineering managers and senior developers covering:

  • Core Skills: Deep dives into React, JavaScript, HTML/CSS, and testing frameworks.
  • Problem-Solving: Whiteboarding or live coding exercises to assess approach to complex UI challenges.
  • System Design: Discussions on how to architect scalable and maintainable front-end solutions.
  • Behavioral Questions: Assessing collaboration, communication, and problem-solving under pressure.

• Manager/Stakeholder Interview: Focus on broader impact, career aspirations, and alignment with Citi's values and operational goals.

• Final Offer: Extension of an offer based on successful completion of all stages.

Portfolio Review Tips:

• Curate Selectively: Choose 2-3 of your strongest projects that best showcase your React proficiency, .NET integration skills (if applicable), and problem-solving abilities.

• Highlight Impact: For each project, clearly articulate the business problem, your specific contributions, the technologies used, and the quantifiable outcomes or improvements achieved (e.g., performance gains, user satisfaction increase, development efficiency).

• Prepare a Walkthrough: Be ready to walk through your code, explain design choices, demonstrate functionality, and discuss any challenges encountered and how you overcame them.

• Focus on Process: Emphasize your development process, including requirements gathering, design considerations, testing strategies, and collaboration methods.

• Tailor to Citi: Understand Citi's focus on security, scalability, and financial services. Frame your project discussions to reflect an understanding of these priorities.

Challenge Preparation:

• Practice Core Concepts: Revisit fundamental JavaScript, React hooks, state management patterns, and common algorithmic problems.

• Simulate Whiteboarding: Practice solving problems on a whiteboard or shared document, articulating your thought process clearly.

• Understand .NET/C# Context: If your projects involved .NET, be ready to discuss API interactions and data flow from a C# perspective.

• Prepare for Behavioral Questions: Use the STAR method (Situation, Task, Action, Result) to structure answers about past experiences, focusing on collaboration, problem-solving, and handling difficult situations.

📝 Enhancement Note: This provides actionable advice for candidates, focusing on how to present their technical skills and project experience in a way that resonates with a large financial institution's hiring process, emphasizing not just coding ability but also process, impact, and professionalism.

🛠 Tools & Technology Stack

Primary Tools:

• React.js: The core JavaScript library for building user interfaces.

• .NET/C#: Likely used for back-end services, APIs, or potentially in a full-stack development context.

• JavaScript (ES6+): Essential for client-side logic.

• TypeScript: Increasingly used for enhanced type safety in large codebases.

• HTML5/CSS3: For structure and styling of web pages.

Analytics & Reporting:

• Browser Developer Tools: Essential for debugging, performance analysis, and inspecting UI elements.

• Performance Monitoring Tools: Tools like Lighthouse, WebPageTest, or integrated APM solutions to analyze load times and user experience.

• Analytics Platforms: Integration with platforms like Google Analytics, Adobe Analytics, or internal Citi solutions for tracking user behavior and application usage.

CRM & Automation:

• Git: For version control and collaborative development workflows.

• JIRA/Confluence: Commonly used for project management, issue tracking, and documentation.

• CI/CD Tools: Jenkins, GitLab CI, Azure DevOps, or similar for automated builds, testing, and deployments.

• Testing Frameworks: Jest, React Testing Library, Cypress for unit, integration, and end-to-end testing.

📝 Enhancement Note: This outlines the expected technology stack, crucial for any developer to understand the technical environment they would be working in. The inclusion of CI/CD and project management tools highlights the enterprise-level development practices at Citi.

👥 Team Culture & Values

Operations Values:

• Integrity & Trust: Paramount in financial services; all development must uphold the highest ethical standards and ensure data security.

• Innovation: Continuously seeking new and better ways to leverage technology to improve financial services and customer experiences.

• Client Focus: Prioritizing the needs of internal business users and external customers in all development efforts.

• Excellence: Striving for high-quality code, robust systems, and efficient processes.

• Collaboration: Working effectively across teams and geographies to achieve shared goals.

Collaboration Style:

• Cross-functional Integration: Developers work closely with product managers, designers, QA, and business stakeholders to ensure alignment and deliver comprehensive solutions.

• Agile & Iterative: Embracing a culture of continuous feedback, adaptation, and incremental delivery.

• Knowledge Sharing: Encouraging open communication, code reviews, and sharing best practices to foster collective growth and learning.

• Problem-Solving Focus: A proactive approach to identifying and resolving technical challenges, often through collaborative brainstorming and pair programming.

📝 Enhancement Note: This section connects the company's broader values to the day-to-day operations of the development team, emphasizing how a Senior UI Developer can contribute to Citi's mission and culture.

⚡ Challenges & Growth Opportunities

Challenges:

• Legacy System Modernization: Transforming older UI components into a modern React framework while ensuring backward compatibility and minimal disruption to critical financial operations.

• Scale and Complexity: Working with a vast, globally distributed financial system requires careful consideration of performance, security, and data consistency across multiple platforms.

• Regulatory Compliance: Adhering to stringent financial regulations and internal policies in all development activities.

• Cross-Team Dependencies: Navigating complex interdependencies with various back-end teams, infrastructure, and business units to deliver integrated solutions.

Learning & Development Opportunities:

• Advanced React & Front-end Architecture: Opportunities to deepen expertise in cutting-edge front-end technologies and architectural patterns.

• Financial Technology Domain: Gaining in-depth knowledge of financial markets, trading systems, and banking operations.

• Cloud Technologies: Exposure to cloud platforms (e.g., AWS, Azure) often used for modern application deployment and scaling.

• Leadership Development: Mentorship programs and training to develop skills for leading technical teams and projects.

• Industry Conferences & Certifications: Support for attending relevant tech conferences and pursuing professional certifications.

📝 Enhancement Note: Identifying potential challenges helps candidates prepare for the realities of the role, while highlighting growth opportunities reinforces the value proposition for career-minded professionals.

💡 Interview Preparation

Strategy Questions:

• "Describe a complex UI you've built using React. What were the key challenges, and how did you overcome them, particularly regarding performance and state management?"

  • Preparation Guidance: Focus on a project that demonstrates your ability to handle intricate UI logic. Quantify performance improvements if possible. Detail your state management strategy and why you chose it.

• "How would you approach migrating a legacy .NET-based UI component to a modern React application while ensuring seamless integration and minimal downtime?"

  • Preparation Guidance: Discuss phased migration strategies, API design for decoupling, testing approaches, and communication plans with stakeholders.

• "Walk me through your process for implementing automated testing for a new React component. What types of tests would you prioritize and why?"

  • Preparation Guidance: Explain your understanding of unit, integration, and end-to-end testing. Mention specific tools and frameworks you're comfortable with (Jest, React Testing Library, Cypress). Company & Culture Questions:

• "How do you ensure your development practices align with the security and compliance requirements of a financial institution like Citi?"

  • Preparation Guidance: Emphasize your understanding of risk management, secure coding practices (e.g., OWASP), and adherence to policies. Mention experience with audits or regulatory environments.

• "Describe a time you had to collaborate with a non-technical stakeholder or a team with different priorities. How did you ensure alignment and successful project delivery?"

  • Preparation Guidance: Use the STAR method. Focus on communication skills, empathy, and finding common ground to achieve project goals. Portfolio Presentation Strategy:

• Concise & Impactful: Prepare a brief overview of each selected project, focusing on the "why" and the "what."

• Technical Deep Dive: Be ready to answer detailed questions about your code, architectural decisions, and problem-solving approaches.

• Demonstrate Value: Clearly articulate how your work contributed to business objectives, efficiency, or user satisfaction. Use metrics where possible.

• Interactive Walkthrough: If possible, have a live demo or interactive screenshots ready to showcase the functionality.

📝 Enhancement Note: This provides targeted interview preparation advice, focusing on questions relevant to a Senior UI Developer role at a financial institution, emphasizing both technical prowess and operational awareness.

📌 Application Steps

To apply for this operations position:

• Submit your application through the official Citi careers portal via the provided job URL.

• Curate Your Resume: Tailor your resume to highlight your experience with .NET/C#, React, HTML5, CSS3, JavaScript, and automated testing. Quantify achievements with specific metrics (e.g., "Improved page load time by 20%," "Reduced bug rate by 15% through comprehensive unit testing").

• Prepare Your Portfolio: Select 2-3 key projects that best demonstrate your skills. Ensure code is clean, well-documented, and accessible (e.g., via GitHub, personal website). Be ready to discuss your contributions, technical decisions, and the impact of your work.

• Research Citi's Tech: Familiarize yourself with Citi's technology initiatives, their approach to innovation in finance, and their commitment to security and compliance. Understand their use of modern technologies.

• Practice Interview Responses: Prepare answers for common technical, behavioral, and situational interview questions, focusing on the STAR method for behavioral questions and demonstrating a strong understanding of the role's responsibilities and the company's context.

⚠️ Important Notice: This enhanced job description includes AI-generated insights and operations industry-standard assumptions. All details should be verified directly with the hiring organization before making application decisions.

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