Job description

Senior UI/UX Developer If you’re the kind of front-end engineer who can take a complex existing product, understand its architecture, and transform the experience without tearing apart the codebase, this is the role for you. We’re looking for a Senior Front-End Engineer who brings together deep production engineering skills, a strong visual eye, and the ability to work confidently inside open-source and third-party platforms . You’ll help shape the front end of AI and analytics applications including Open WebUI, LiteLLM Admin UI, Arize, Phoenix, Archestra, and similar tools —extending and theming these products so they feel cohesive, polished, accessible, and aligned to a world-class enterprise design system. This is a role for someone who enjoys the challenge of making an existing product feel custom-built : translating sophisticated Figma designs into production code, refining data-dense workflows, building reusable UI patterns, and finding smart ways to customize upstream products while preserving clean upgrade paths. You’ll partner closely with UX designers, product managers, and platform engineers, bringing the engineering judgment to know what to customize, what to leave intact, and how to deliver high visual fidelity without creating unnecessary technical debt . The strongest candidates combine the instincts of a designer with the discipline of a production front-end engineer. You care about spacing, typography, interaction, accessibility, performance, maintainability, and the details users notice—even when they can’t explain why. Locations: Glendale/Anaheim, CA; Seattle, WA; or Orlando, FL Work Arrangement: Hybrid / 2-3 days a week onsite presence required at one of the designated locations What You Will Do • Customize and extend existing open-source and vendor-provided user interfaces. • Apply enterprise branding, visual standards, typography, spacing, colors, iconography, and interaction patterns to existing products. • Translate complex Figma files and design-system components into production-ready front-end code. • Build responsive, reusable UI components for dashboards, admin consoles, configuration screens, tables, forms, charts, and data-heavy workflows. • Theme and white-label existing applications using CSS, design tokens, configuration, and component-level customization. • Extend Svelte/SvelteKit-based interfaces, including applications built on Open WebUI or similar platforms. • Work with React or other modern front-end frameworks when needed. • Integrate front-end components with REST/JSON APIs and handle loading, error, empty, and state-management scenarios appropriately. • Maintain upgrade-friendly customization approaches rather than unnecessarily forking or rewriting third-party products. • Partner with UX teams to refine implementation details, clarify edge cases, and identify practical design tradeoffs. • Implement accessible interfaces using WCAG, ARIA, keyboard navigation, proper focus management, and contrast standards. • Contribute to shared component libraries, design tokens, theming conventions, and front-end standards. • Perform UI reviews and help establish a high standard for visual fidelity and front-end quality. • Work with Python-based administrative applications when light template, configuration, or UI-layer changes are required. Required Qualifications • 5+ years of professional front-end development experience building production web applications. • Strong hands-on experience with HTML, CSS, and JavaScript . • Strong understanding of responsive layouts, cross-browser behavior, spacing, typography, component composition, and visual consistency. • Demonstrated experience working directly from Figma design files and design systems . • Experience theming, white-labeling, reskinning, or extending an existing product, platform, admin console, or third-party application . • Experience building or maintaining data-dense application interfaces , such as: • dashboards • admin consoles • configuration screens • complex forms • tables • charts • analytics tools • Experience with at least one modern front-end framework such as Svelte/SvelteKit, React, Angular, or Vue . • Experience integrating front-end applications with REST/JSON APIs. • Strong understanding of front-end accessibility and responsive design. • Ability to collaborate effectively with UX designers, product managers, and engineers. • Strong attention to visual detail and demonstrated ability to translate design intent accurately into production code. • Working portfolio with shipped production work is required. Strongly Preferred • Svelte / SvelteKit experience. • Experience customizing Open WebUI or other Svelte-based applications. • Experience with LiteLLM Admin UI . • Experience with AI or LLM platforms such as: • Open WebUI • LiteLLM • Arize / Phoenix • LangSmith • Langfuse • Archestra • similar LLM observability or AI-admin platforms • Experience with enterprise-scale design systems or design-token ownership. • Strong WCAG/accessibility implementation experience, including remediation or accessibility audits. • Experience creating custom icons, graphics, illustrations, or extending an existing brand system. • Python familiarity sufficient to work with templates, configuration, or UI layers within Python-based applications. • Experience working with open-source projects while maintaining clean upgrade paths. What Makes HTC A Great Place To Build Your Future HTC Global Services wants you to join our team. Come build new things with us and advance your career. At HTC Global, you’ll collaborate with experts, work alongside clients, and be part of high-performing teams driving success together. You’ll have long-term opportunities to grow your career and develop skills in the latest emerging technologies. At HTC Global Services, our employees have access to a comprehensive benefits package. Benefits can include Group Health (Medical, Dental, and Vision), Paid Time Off, Paid Holidays, 401(k) matching, Group Life and Disability insurance, Professional Development opportunities, Wellness programs, and a variety of other perks. Our success as a company is built on inclusion and diversity. HTC Global Services is committed to providing a workplace free from discrimination and harassment, where every employee is treated with dignity and respect. We celebrate differences and believe that diverse cultures, perspectives, and skills drive innovation and success. HTC is an Equal Opportunity Employer and a proud National Minority Supplier. We seek to empower each individual, fostering an environment where everyone feels valued, included, and respected. What Makes HTC A Great Place To Build Your Future HTC Global Services wants you to join our team. Come build new things with us and advance your career. At HTC Global, you’ll collaborate with experts, work alongside clients, and be part of high-performing teams driving success together. You’ll have long-term opportunities to grow your career and develop skills in the latest emerging technologies. At HTC Global Services, our employees have access to a comprehensive benefits package. Benefits can include Group Health (Medical, Dental, and Vision), Paid Time Off, Paid Holidays, 401(k) matching, Group Life and Disability insurance, Professional Development opportunities, Wellness programs, and a variety of other perks. Our success as a company is built on inclusion and diversity. HTC Global Services is committed to providing a workplace free from discrimination and harassment, where every employee is treated with dignity and respect. We celebrate differences and believe that diverse cultures, perspectives, and skills drive innovation and success. HTC is an Equal Opportunity Employer and a proud National Minority Supplier. We seek to empower each individual, fostering an environment where everyone feels valued, included, and respected. #LI-Hybrid #LI-DT1 #LI-NC1 # Hiring

Requirements

Must-haves

Senior UI/UX Developer
If you’re the kind of front-end engineer who can take a complex existing product, understand its architecture, and transform the experience without tearing apart the codebase, this is the role for you.
We’re looking for a Senior Front-End Engineer who brings together deep production engineering skills, a strong visual eye, and the ability to work confidently inside open-source and third-party platforms .
Locations: Glendale/Anaheim, CA; Seattle, WA; or Orlando, FL
Work Arrangement: Hybrid / 2-3 days a week onsite presence required at one of the designated locations
Customize and extend existing open-source and vendor-provided user interfaces.
Apply enterprise branding, visual standards, typography, spacing, colors, iconography, and interaction patterns to existing products.
Translate complex Figma files and design-system components into production-ready front-end code.
Build responsive, reusable UI components for dashboards, admin consoles, configuration screens, tables, forms, charts, and data-heavy workflows.
Theme and white-label existing applications using CSS, design tokens, configuration, and component-level customization.
Extend Svelte/SvelteKit-based interfaces, including applications built on Open WebUI or similar platforms.
Work with React or other modern front-end frameworks when needed.
Integrate front-end components with REST/JSON APIs and handle loading, error, empty, and state-management scenarios appropriately.
Maintain upgrade-friendly customization approaches rather than unnecessarily forking or rewriting third-party products.
Partner with UX teams to refine implementation details, clarify edge cases, and identify practical design tradeoffs.
Implement accessible interfaces using WCAG, ARIA, keyboard navigation, proper focus management, and contrast standards.
Contribute to shared component libraries, design tokens, theming conventions, and front-end standards.
Perform UI reviews and help establish a high standard for visual fidelity and front-end quality.
Work with Python-based administrative applications when light template, configuration, or UI-layer changes are required.
5+ years of professional front-end development experience building production web applications.
Strong hands-on experience with HTML, CSS, and JavaScript .
Strong understanding of responsive layouts, cross-browser behavior, spacing, typography, component composition, and visual consistency.
Demonstrated experience working directly from Figma design files and design systems .

Nice-to-haves

Strongly Preferred

Application prep

Use the role’s language and application details while tailoring your materials.

Keywords to mirror

aidesign systemfigmaaccessibilitysveltereactrestpythonjavascriptdesign systemsangularvuellm

Platform: htc-global
Effort: medium

Benefits

Benefits detected in the listing.

Dental

Vision

401(K)

Paid Time Off

Wellness

Professional Development