Sr Front-End Engineer

KTek Resourcing LLC; Wilmington (DE); On-site; USD 140,000 - 190,000; Full time

Job summary

KTek Resourcing LLC seeks a senior frontend engineer to lead high-performance web experiences using React and to collaborate with a Java Spring backend. You will own frontend architecture, drive standards, and implement advanced UI features across microservices.

Expert react proficiency, strong Java/Spring, and experience with modern tooling, testing, accessibility, and security are required. AI-assisted coding tools are encouraged to accelerate delivery while maintaining quality.

Qualifications

• 12+ years of professional software engineering in frontend.
• Expert-level React with hooks, context and rendering behavior.
• Strong Java and Spring for microservices and API contracts.
• Experience with modern frontend tooling and build pipelines.
• Advanced testing with Jest/Vitest and RTL.
• Accessibility (WCAG/ARIA) expertise.
• Performance optimization and Core Web Vitals mastery.
• GraphQL/REST API integration and client state management.
• Security-focused patterns for web apps.
• Observability and debugging in production.
• Proficiency with AI-assisted coding tools.

Responsibilities

• Lead development of complex, user-facing web applications using React, owning the front-end architecture and delivery approach.
• Develop microservices / API contracts (GraphQL/REST) using Java and Spring with front-end friendly patterns.
• Establish and evolve front-end standards: components, state, routing, testing.
• Drive performance and quality: Core Web Vitals, bundle optimization, caching, observability.
• Implement advanced UI capabilities: real-time updates, offline patterns, robust forms.
• Ensure secure client-side patterns: auth flows, token handling, storage, protection against vulnerabilities.

Skills

React expert

Java Spring

Frontend tooling

Testing

Accessibility

Performance

API GraphQL/REST

Security

Observability

AI tooling

Leadership

Tools

Vite/Webpack

Babel SWC

NPM/Pnpm/Yarn

Storybook

D3/Canvas

Job description

Lead the design and development of modern, high-performance web experiences using React and the broader front-end ecosystem. This role is front-end (React) 60% and backend (Java Spring) 40% focused skills to deliver cutting-edge UI & Microservices capabilities and set engineering standards.

Job responsibilities

• Lead development of complex, user-facing web applications using React, owning the front-end architecture and delivery approach.
• Develop microservices / API contracts (GraphQL/REST) using Java and Spring technologies and front-end friendly design patterns (pagination, filtering, error models).
• Establish and evolve front-end standards: component architecture, state management, routing, code conventions, and testing practices.
• Drive performance and quality: Core Web Vitals, bundle optimization, rendering strategies, caching, and runtime observability.
• Implement advanced UI capabilities such as rich data visualization, real-time updates, offline-friendly patterns, and robust form/workflow experiences.
• Ensure secure client-side patterns: safe auth flows, token handling guidance, secure storage, and protection against common web vulnerabilities.

Required qualifications, capabilities, and skills

• 12+ years professional software engineering experience with significant depth in front-end web development; experience leading projects and mentoring engineers.
• Expert-levelReact proficiency (hooks, component composition, context, rendering behavior, concurrency-related patterns where applicable).
• Strong Java and Java Spring skills to develop microservices / API contracts (GraphQL/REST) using Java and Spring technologies and front-end friendly design patterns (pagination, filtering, error models).
• Deep experience with modern front-end tooling: Vite/Webpack, Babel/SWC, npm/pnpm/yarn, monorepos (optional), and build/release pipelines.
• Advanced testing practices: Jest/Vitest, React Testing Library, Playwright/Cypress for E2E; test strategy ownership.
• Accessibility expertise: WCAG/ARIA, keyboard navigation, screen-reader considerations, and automated + manual a11y testing.
• Performance engineering: profiling, bundle splitting, SSR/CSR trade-offs, caching strategies, and Core Web Vitals optimization.
• API integration expertise with GraphQL and REST (schema-driven development, error handling, pagination, caching, and client state strategies).
• Security awareness for web apps: XSS/CSRF prevention, dependency hygiene, secure auth/session patterns (OIDC awareness a plus).
• Observability for the front end: client-side logging/metrics, error reporting, and debugging production issues.
• MUST: Proficiency using AI-assisted engineering tools (e.g., Claude Code, GitHub Copilot) to accelerate implementation, refactoring, test creation, and debugging—while validating correctness and adhering to secure handling practices.

Preferred qualifications

• Experience with SSR/meta frameworks: Next.js / Remix and SEO considerations.
• Experience leveraging a design system (Storybook, tokens).
• Experience with micro-frontend patterns and module federation (where relevant).
• Experience with visualization and rich UI: D3, Canvas/WebGL, advanced tables/grids, animation libraries.
• Familiarity with authentication integrations (OIDC/OAuth2) and enterprise SSO constraints.
• Proven track record modernizing legacy front ends and improving developer experience (DX).