Senior Front-End UI/UX Engineer

This position is listed on behalf of a partner company, who manages all applications and next steps. Our partner is looking for a Senior Front-End UI/UX Engineer based in United States. This role is an opportunity to shape intuitive, accessible, and high-quality digital experiences for complex enterprise applications. You will combine strong front-end engineering expertise with a deep understanding of UI/UX and accessibility principles. Working primarily within an ASP.NET MVC 5 environment, you will translate business and user needs into polished, maintainable interfaces. Your work will help ensure applications are usable, inclusive, responsive, and compliant with modern accessibility standards. You will collaborate closely with business stakeholders, customers, designers, QA specialists, and technology teams. The position offers a hands-on engineering environment where you can influence both technical implementation and the overall user experience. You will also contribute to technical specifications, testing, documentation, and the delivery of reliable production-ready solutions. Design, develop, enhance, and maintain accessible, user-centered interfaces for complex enterprise applications built on ASP.NET MVC 5. Translate business requirements, user needs, and design concepts into clean, intuitive, maintainable, and production-ready front-end experiences. Apply UI/UX principles including information architecture, interaction design, visual hierarchy, usability, and responsive design to real-world applications. Implement and validate web accessibility in accordance with WCAG 2.1/2.2 AA and Section 508 requirements. Apply semantic HTML, ARIA roles and attributes, keyboard navigation, focus management, and other accessibility best practices. Test interfaces using assistive technologies and screen readers such as JAWS, NVDA, and VoiceOver, as appropriate. Develop and support full-stack .NET applications using C#, ASP.NET MVC 5, SQL Server, and related Microsoft technologies in a Windows environment. Build and integrate front-end experiences with RESTful APIs and internal or external systems. Work with Microsoft SQL Server, including data models, T-SQL queries, stored procedures, and views required to support application functionality. Prepare technical design specifications, technical documentation, and clear design documentation. Write and maintain unit tests while supporting QA, usability testing, accessibility validation, and release activities. Analyze requirements, troubleshoot complex UI and cross-browser issues, and deliver stable, polished solutions within established timelines. Collaborate with business stakeholders, customers, designers, and cross-functional technology teams to validate solutions and resolve issues. Contribute to design reviews, accessibility audits, usability initiatives, and continuous improvements to the application's user experience. Work independently within established enterprise codebases while identifying opportunities to modernize and improve legacy front-end components. Requirements Bachelor’s degree in Computer Science, Human-Computer Interaction, Design, Engineering, or a related field, or equivalent practical experience. 5–8+ years of professional software development experience, with significant hands-on experience in front-end and UI development. Strong proficiency in HTML5, CSS3, JavaScript, and jQuery, with a focus on clean, semantic, maintainable markup. Demonstrated ability to apply UI/UX principles such as information architecture, interaction design, visual hierarchy, usability, and user-centered design. Hands-on experience implementing and testing accessible web experiences against WCAG 2.1/2.2 AA and Section 508 standards. Practical knowledge of ARIA, semantic HTML, keyboard navigation, focus management, and accessibility testing with assistive technologies. Strong proficiency in C# and ASP.NET MVC 5, with experience developing and supporting full-stack .NET applications in Wind