Senior Full Stack UI Engineer (5+ Years in React.js, TypeScript/JavaScript and RESTful APIs)

📍 Job Overview

Job Title: Senior Full Stack UI Engineer

Company: FIS

Location: Pune, Maharashtra, India

Job Type: Full-time

Category: Software Engineering / Full Stack Development

Date Posted: August 19, 2026

Experience Level: Senior (5+ Years)

Remote Status: On-site

🚀 Role Summary

• Design, develop, and enhance scalable web applications with a strong focus on user experience and critical business outcomes.

• Drive application architecture, technical design, and development best practices for both front-end and full-stack solutions.

• Build reusable, maintainable components to improve development efficiency and ensure consistency across projects.

• Develop and integrate RESTful APIs and backend services to support application functionality and optimize performance.

• Implement robust security measures, including authentication, authorization, and data protection practices.

📝 Enhancement Note: While the job title specifies "UI Engineer," the responsibilities clearly indicate a Full Stack role, requiring backend integration and API development alongside front-end expertise. The emphasis on "scalable web applications" and "critical business outcomes" suggests a need for robust, enterprise-level solutions within the fintech domain.

📈 Primary Responsibilities

• Design and develop responsive, scalable web applications utilizing modern front-end technologies and frameworks, with a primary focus on React.js.

• Collaborate closely with product management and user experience teams to translate complex business requirements into intuitive and user-friendly digital interfaces.

• Lead and drive application architecture decisions, technical design, and the implementation of development best practices for both front-end and full-stack solutions.

• Create and maintain a library of reusable, maintainable components and modules that enhance development efficiency and ensure design consistency across the platform.

• Develop, test, and integrate RESTful APIs and backend services, ensuring seamless interaction with front-end applications and optimal performance.

• Optimize application performance through strategic caching, proactive monitoring, and a commitment to continuous improvement initiatives.

• Implement and enforce secure authentication, authorization, and data protection practices throughout the application lifecycle.

• Engage with cross-functional teams, including QA, product, and other engineering disciplines, to effectively resolve technical challenges and ensure the delivery of high-quality software solutions.

• Provide essential support for production environments, including troubleshooting, in-depth root cause analysis, and implementing continuous enhancement measures.

• Actively participate in code reviews, contribute to the development of comprehensive testing strategies, maintain thorough documentation, and foster knowledge sharing within the engineering organization.

📝 Enhancement Note: The responsibilities highlight a senior-level contribution, expecting the engineer to not only develop but also "drive" architectural decisions and "lead" best practices. This implies a need for strong technical leadership and the ability to mentor junior engineers.

🎓 Skills & Qualifications

Education: Bachelor's degree in Computer Science, Engineering, or a related field, or equivalent practical experience.

Experience: Minimum of 5 years of professional experience in full-stack web application development, with a significant focus on front-end technologies.

Required Skills:

• Demonstrated 5+ years of experience developing modern web applications using React.js and TypeScript/JavaScript.

• Strong understanding and application of user-centered design principles in front-end development.

• Expertise in designing scalable, maintainable, and high-performing software architectures for complex applications.

• Proven experience in building and consuming RESTful APIs and integrating distributed services.

• Solid knowledge of authentication protocols, application security principles, and secure coding practices.

• Experience working with relational databases such as PostgreSQL, Oracle, or similar technologies.

• Proficiency in software development lifecycle (SDLC) practices, including comprehensive testing, code reviews, and CI/CD workflows.

• Excellent analytical, problem-solving, communication, and collaboration skills, with a demonstrated ability to influence technical decisions. Preferred Skills:

• Experience with Angular or other modern front-end frameworks.

• Experience with Node.js and backend frameworks such as Express.

• Knowledge of functional programming concepts and relevant frameworks.

• Experience developing and supporting Software-as-a-Service (SaaS) platforms.

• Familiarity with front-end build, automation, and DevOps tooling.

• Hands-on experience with unit, integration, and end-to-end testing frameworks.

📝 Enhancement Note: The "5+ Years" requirement is explicitly stated, reinforcing the senior nature of the role. The inclusion of both front-end and backend skills (databases, APIs) confirms the full-stack expectation. Preferred skills like Node.js, Express, and SaaS experience suggest a leaning towards modern, cloud-native development environments.

📊 Process & Systems Portfolio Requirements

Portfolio Essentials:

• Showcase examples of complex, scalable web applications developed using React.js and TypeScript/JavaScript.

• Demonstrate proficiency in designing and implementing RESTful APIs and backend integrations.

• Provide case studies highlighting contributions to application architecture and technical design decisions.

• Include examples of reusable component libraries or design systems developed to enhance development efficiency.

• Present evidence of implementing security best practices, including authentication and authorization mechanisms. Process Documentation:

• Detail the software development lifecycle (SDLC) processes followed, emphasizing CI/CD and testing methodologies.

• Illustrate workflow optimization strategies and how they contributed to improved application performance or developer productivity.

• Document experience with root cause analysis and troubleshooting for production environments.

• Showcase contributions to establishing or improving code review standards and knowledge-sharing practices.

📝 Enhancement Note: For a senior role, a portfolio is crucial. It should not just list technologies but demonstrate how they were applied to solve complex problems, optimize processes, and deliver business value, particularly in areas like scalability, security, and performance.

💵 Compensation & Benefits

Salary Range: Given the senior level (5+ years experience), location (Pune, India), and the required high-demand skills (React.js, TypeScript, RESTful APIs, full-stack capabilities), a competitive salary range for a Senior Full Stack UI Engineer in Pune would typically fall between ₹15,00,000 and ₹25,00,000 per annum. This range is an estimate based on industry benchmarks for similar roles in major Indian tech hubs, considering the fintech sector's compensation trends. Actual compensation will be determined by the candidate's specific experience, qualifications, and performance during the interview process.

Benefits:

• Competitive salary and performance-based bonuses.

• Opportunities for personal and professional learning and development, including access to training resources and potential certifications.

• Inclusive and diverse work environment that values collaboration and innovation.

• Resources and initiatives to support community engagement and give back.

• Comprehensive health and wellness benefits (details typically provided during the offer stage).

• Potential for career advancement within a global fintech leader.

Working Hours: Standard full-time work hours, typically 40 hours per week. While the role is on-site, there may be flexibility in daily start/end times, subject to team coordination and project needs. Occasional overtime may be required to meet project deadlines or address critical production issues.

📝 Enhancement Note: The salary estimate is based on research of senior software engineering roles in Pune, India, with comparable technology stacks and experience requirements. The benefits listed are derived from the "What We Offer you" section of the job description and common offerings for senior tech roles in multinational corporations.

🎯 Team & Company Context

🏢 Company Culture

Industry: Financial Technology (Fintech). FIS is a global leader in financial services technology, providing a wide range of solutions for banks, credit unions, investment firms, and merchants. This means the work will be in a highly regulated, fast-paced environment with a strong emphasis on security, reliability, and innovation.

Company Size: Large Enterprise. FIS is a significant global corporation with a substantial employee base (likely thousands worldwide). This implies a structured corporate environment with established processes, numerous career paths, and opportunities for cross-departmental exposure.

Founded: The company has a long history, contributing to its stability and deep expertise in the financial services sector. Understanding this history can provide context for the company's evolution and its current strategic direction.

Team Structure:

• The engineering team is likely structured into specialized squads or pods, focusing on specific product areas or functionalities. This Senior Full Stack UI Engineer will be part of a team responsible for developing and maintaining key web applications.

• Reporting will likely be to an Engineering Manager or Team Lead, with direct collaboration with Product Managers, UX Designers, and other engineers (front-end, back-end, QA).

• Cross-functional collaboration is essential, working closely with architecture, security, and operations teams to ensure solutions are robust, secure, and scalable. Methodology:

• Data Analysis and Insights: Decisions will be data-driven, leveraging application performance metrics, user feedback, and business analytics to guide development and identify areas for improvement.

• Workflow Planning and Optimization: Emphasis on efficient development workflows, utilizing Agile methodologies (e.g., Scrum, Kanban) to manage sprints, track progress, and adapt to changing requirements.

• Automation and Efficiency: Strong focus on automating repetitive tasks, implementing CI/CD pipelines, and utilizing tools that enhance developer productivity and ensure reliable deployments.

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

📝 Enhancement Note: The company's position as a fintech leader is critical. Operations professionals in this sector must be acutely aware of regulatory compliance, data security, and the need for high availability and performance. The "Intro" section emphasizes innovation and global impact.

📈 Career & Growth Analysis

Operations Career Level: Senior Full Stack UI Engineer. This level signifies a highly experienced individual contributor expected to lead technical initiatives, mentor junior engineers, and have significant influence over architectural decisions and development practices. The role requires deep expertise in React.js, TypeScript, and full-stack development, coupled with strong problem-solving and communication skills.

Reporting Structure: The role reports to an Engineering Manager or Team Lead. The engineer will be expected to collaborate closely with peers across various engineering disciplines, as well as with Product Managers, UX Designers, and potentially architects. This structure emphasizes both independent contribution and team-based collaboration.

Operations Impact: This role directly impacts the user experience of critical financial applications, influencing customer satisfaction, operational efficiency, and the adoption of new features. By building scalable, secure, and high-performing web applications, the engineer contributes to FIS's ability to serve its clients effectively and maintain its competitive edge in the fintech market. Their work underpins the delivery of financial services, impacting revenue streams and client trust.

Growth Opportunities:

• Technical Specialization: Deepen expertise in React.js, explore advanced JavaScript/TypeScript patterns, or specialize in specific backend technologies and API design.

• Architectural Leadership: Grow into roles focused on designing complex system architectures, leading technical strategy for product areas, or becoming a Principal Engineer.

• Team Leadership: Transition into a Tech Lead or Engineering Manager role, guiding and mentoring teams, and overseeing project execution.

• Cross-functional Exposure: Gain experience in areas like DevOps, cloud infrastructure, security engineering, or product management through collaboration and internal mobility.

• Industry Expertise: Develop deeper knowledge of the fintech domain, understanding the intricacies of financial services technology and regulatory landscapes.

📝 Enhancement Note: The "Senior" title and the breadth of responsibilities suggest significant growth potential beyond individual contribution, including leadership and architectural influence, especially within a large organization like FIS.

🌐 Work Environment

Office Type: The role is specified as "On-site" in Pune, India. This indicates a traditional office-based work environment where collaboration and team interaction are expected to occur in person.

Office Location(s): The primary office location is listed as "IND PUNE FL2." This likely refers to a specific building or floor within a larger FIS campus or office complex in Pune.

Workspace Context:

• Collaborative Environment: The office setting is designed to foster collaboration, with shared workspaces, meeting rooms, and common areas for informal discussions.

• Operations Tools and Technology: Access to standard corporate IT infrastructure, development tools, and potentially specialized hardware or software required for fintech development and testing.

• Team Interaction: Frequent face-to-face interactions with team members, including code reviews, brainstorming sessions, and project stand-ups, facilitating rapid communication and problem-solving.

Work Schedule: A standard 40-hour work week is typical for full-time positions. While the core hours may be fixed, there might be some flexibility in daily start and end times, subject to team coordination and manager approval, to accommodate project needs and team collaboration.

📝 Enhancement Note: The "On-site" requirement is a key differentiator. Candidates should expect a traditional office setup and be prepared for in-person collaboration, which can be beneficial for team cohesion and rapid problem-solving in complex projects.

📄 Application & Portfolio Review Process

Interview Process:

• Initial Screening: Likely a recruiter or HR screening to assess basic qualifications, experience, and cultural fit.

• Technical Assessment: May involve a coding challenge (live or take-home) focusing on React.js, TypeScript, JavaScript, and problem-solving skills.

• Technical Interviews: Multiple rounds with engineering team members and leads, delving into software architecture, RESTful API design, database knowledge, and security principles. Expect deep dives into past projects and technical decision-making.

• System Design Interview: A senior-level interview focusing on designing scalable and robust web applications, evaluating architectural choices, and trade-offs.

• Manager/Team Lead Interview: Discussion on leadership potential, team collaboration, career aspirations, and alignment with FIS's culture and values.

• Final Round: Potentially with senior leadership or a hiring manager for final approval.

Portfolio Review Tips:

• Curate Select Projects: Choose 2-3 impactful projects that best showcase your expertise in React.js, TypeScript, full-stack development, and API integration.

• Highlight Contributions: Clearly articulate your specific role and contributions in each project, focusing on the challenges you solved and the solutions you implemented.

• Demonstrate Process: Explain the SDLC, development methodologies (CI/CD, testing), and architectural patterns used.

• Quantify Impact: Wherever possible, use metrics to demonstrate the positive impact of your work (e.g., performance improvements, efficiency gains, user adoption rates).

• Prepare for Deep Dives: Be ready to discuss the technical details, trade-offs, and decision-making process behind your portfolio projects in depth.

Challenge Preparation:

• Coding Proficiency: Practice coding challenges on platforms like LeetCode or HackerRank, focusing on data structures, algorithms, and JavaScript/TypeScript problem-solving.

• System Design: Study common system design patterns, scalability considerations, and trade-offs for building complex web applications. Review resources on microservices, APIs, and database design.

• React.js & TypeScript: Refresh your knowledge of advanced React concepts (hooks, context API, performance optimization) and TypeScript features.

• API Design: Understand REST principles, API versioning, authentication methods (OAuth, JWT), and common API design patterns.

• Security Best Practices: Familiarize yourself with common web vulnerabilities (OWASP Top 10) and how to mitigate them through secure coding practices and authentication/authorization mechanisms.

📝 Enhancement Note: The interview process for a senior role is rigorous. Candidates should be prepared for in-depth technical discussions and be able to articulate their contributions and decision-making processes clearly, supported by their portfolio.

🛠 Tools & Technology Stack

Primary Tools:

• Front-end Framework: React.js (primary focus), potentially Angular (preferred).

• Languages: TypeScript, JavaScript.

• API Development/Integration: RESTful APIs, potentially GraphQL.

• Backend Technologies: Node.js, Express (preferred).

• Databases: PostgreSQL, Oracle (required), other relational databases.

• Version Control: Git (essential).

Analytics & Reporting:

• Web analytics tools (e.g., Google Analytics, Adobe Analytics) for user behavior tracking.

• Performance monitoring tools (e.g., New Relic, Datadog) for application health and optimization.

• Dashboarding tools (e.g., Tableau, Power BI, Grafana) for visualizing key metrics. CRM & Automation:

• While not explicitly mentioned for this role, familiarity with CRM systems (e.g., Salesforce) and marketing automation platforms is often beneficial in a full-stack context for understanding data flow and business integration.

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

• DevOps Tooling: Docker, Kubernetes (potentially), cloud platforms (AWS, Azure, GCP).

📝 Enhancement Note: The technology stack is heavily weighted towards modern JavaScript/TypeScript ecosystems. Proficiency in React.js is non-negotiable, with Node.js and Express being strong advantages. Understanding CI/CD and DevOps principles is critical for a senior engineer involved in full-stack development.

👥 Team Culture & Values

Operations Values:

• Innovation: Driving forward with new technologies and approaches to create cutting-edge fintech solutions.

• Customer Focus: Designing and building products that deliver exceptional user experiences and meet client needs.

• Integrity & Security: Upholding the highest standards of data protection, privacy, and ethical conduct in all aspects of development.

• Collaboration: Working effectively across teams to achieve shared goals and foster a supportive environment.

• Excellence: Striving for technical mastery, robust solutions, and continuous improvement in all work.

Collaboration Style:

• Cross-functional Integration: Engineers are expected to collaborate closely with product managers, UX designers, QA testers, architects, and other engineering teams to ensure holistic product development.

• Process Review Culture: Openness to constructive feedback through code reviews and regular team retrospectives to refine processes and improve code quality.

• Knowledge Sharing: A culture that encourages sharing best practices, technical insights, and lessons learned through internal presentations, documentation, and mentoring.

📝 Enhancement Note: FIS operates in the highly sensitive fintech sector, so values like integrity, security, and customer focus are paramount. The emphasis on collaboration and excellence is standard for high-performing engineering teams.

⚡ Challenges & Growth Opportunities

Challenges:

• Scalability and Performance: Ensuring web applications can handle increasing user loads and data volumes while maintaining optimal performance in a demanding fintech environment.

• Security and Compliance: Adhering to stringent security protocols and regulatory requirements inherent in financial services technology, requiring constant vigilance and robust implementation.

• Rapid Technology Evolution: Keeping pace with the fast-changing landscape of front-end and full-stack technologies, requiring continuous learning and adaptation.

• Complex Integrations: Seamlessly integrating with diverse backend services, legacy systems, and third-party APIs within the FIS ecosystem.

Learning & Development Opportunities:

• Advanced Training: Access to online learning platforms, workshops, and internal training programs focused on React.js, TypeScript, cloud technologies, and advanced software architecture.

• Industry Conferences: Opportunities to attend relevant tech conferences (e.g., React Conf, Google I/O, AWS re:Invent) to stay abreast of industry trends and network with peers.

• Mentorship Programs: Participation in formal or informal mentorship programs to guide career growth, develop leadership skills, and gain insights from experienced professionals.

• Cross-functional Projects: Opportunities to work on projects that span different technical domains or business units, broadening overall understanding of the fintech landscape.

📝 Enhancement Note: The challenges are typical for senior roles in established tech companies, especially in regulated industries like fintech. The growth opportunities are geared towards continuous skill enhancement and career progression within a large organization.

💡 Interview Preparation

Strategy Questions:

• "Describe a complex web application architecture you designed. What were the key considerations for scalability, security, and performance?" (Focus on demonstrating your architectural thinking, trade-offs, and ability to apply principles like RESTful APIs, database design, and authentication.)

• "Walk me through a challenging bug you encountered in a React.js application. How did you approach troubleshooting and what was the resolution?" (Prepare a specific example showcasing your problem-solving methodology, debugging skills, and understanding of the SDLC.)

• "How do you ensure the security of your front-end and full-stack applications? Discuss your experience with authentication protocols and secure coding practices." (Be ready to discuss specific security measures, potential vulnerabilities, and how you mitigate them.) Company & Culture Questions:

• "Why are you interested in working at FIS, and what excites you about the fintech industry?" (Research FIS's mission, recent news, and its role in the financial ecosystem. Connect your skills and interests to their business.)

• "How do you approach collaboration with non-technical stakeholders like product managers or UX designers?" (Highlight your communication skills, ability to translate technical concepts, and focus on user-centric outcomes.)

• "Describe a time you had to influence a technical decision within your team. What was your approach and the outcome?" (Prepare an example that demonstrates your leadership, technical rationale, and collaborative skills.) Portfolio Presentation Strategy:

• Structure Your Narrative: For each project, follow a STAR (Situation, Task, Action, Result) or similar structured approach. Clearly define the problem, your role, the technical solutions you implemented (highlighting React.js, TypeScript, APIs, security), and the measurable outcomes.

• Focus on Key Technologies: Emphasize your proficiency and strategic use of React.js, TypeScript, JavaScript, and RESTful APIs. Discuss why you chose specific tools and patterns.

• Demonstrate Process Rigor: Explain your involvement in the SDLC, including CI/CD, testing strategies, and code review processes.

• Be Ready for Technical Deep Dives: Anticipate detailed questions about your code, architectural choices, and problem-solving approaches. Practice explaining complex technical concepts concisely.

📝 Enhancement Note: Interview preparation should focus on demonstrating senior-level capabilities: technical depth, architectural thinking, problem-solving acumen, and leadership potential, all grounded in practical experience and supported by a well-prepared portfolio.

📌 Application Steps

To apply for this operations position:

• Submit your application through the official FIS careers portal via the provided link.

• Tailor Your Resume: Ensure your resume clearly highlights your 5+ years of experience with React.js, TypeScript/JavaScript, and RESTful APIs. Quantify achievements and responsibilities using keywords from the job description (e.g., "developed scalable web applications," "integrated RESTful APIs," "implemented security best practices").

• Prepare Your Portfolio: Curate 2-3 key projects that best showcase your full-stack capabilities, architectural contributions, and problem-solving skills. Be ready to present these in detail, focusing on your specific role, the technologies used, and the impact achieved.

• Practice Technical Scenarios: Review common interview questions related to React.js, TypeScript, JavaScript, software architecture, API design, and security. Prepare to answer system design questions and potential coding challenges.

• Research FIS: Understand FIS's business, its role in the fintech industry, and its company values. Prepare thoughtful questions to ask the interviewer, demonstrating your engagement and interest.

⚠️ 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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