Find & Apply For UI / UX Designer / Developer Jobs in San Leandro, California

Senior React Developer Location:

San Leandro, CA (Onsite)

Employment Type:

W2 / Full-Time Job Summary We are looking for an experienced Senior React Developer to design, develop, and enhance modern, scalable web applications. The ideal candidate will have strong expertise in React.js, TypeScript, JavaScript, frontend architecture, REST APIs, and modern UI development practices . The developer will work closely with product owners, UX/UI designers, backend engineers, architects, and QA teams to deliver high-quality enterprise applications. Key Responsibilities Design and develop scalable web applications using React.js and TypeScript . Build reusable React components, hooks, and frontend libraries. Develop responsive and accessible user interfaces based on UX/UI designs. Integrate frontend applications with REST APIs and microservices . Manage application state using Redux Toolkit, Context API, Zustand, or similar technologies . Implement routing using React Router or equivalent frameworks. Optimize applications for performance, scalability, and browser compatibility. Develop unit and integration tests using Jest, React Testing Library, Cypress, or Playwright . Troubleshoot complex frontend issues and improve application performance. Participate in architecture discussions and provide technical recommendations. Conduct code reviews and enforce frontend coding standards and best practices. Collaborate with backend, DevOps, QA, UX, and product teams in an Agile/Scrum environment . Support CI/CD pipelines and application deployments. Mentor junior and mid-level frontend developers. Required Skills 7+ years of software development experience with strong frontend development expertise. 5+ years of hands-on experience with React.js . Strong experience with JavaScript ES6+ and TypeScript . Strong understanding of React concepts including: Functional Components Hooks Context API Component Lifecycle State Management Custom Hooks Experience with Redux / Redux Toolkit or similar state-management frameworks. Strong knowledge of HTML5, CSS3, responsive design, Flexbox, and CSS Grid . Experience working with RESTful APIs and JSON . Experience with frontend testing frameworks such as Jest and React Testing Library . Experience with Git, GitHub/GitLab/Bitbucket , and pull-request workflows. Knowledge of CI/CD and DevOps practices . Strong understanding of frontend performance optimization and secure coding practices. Excellent problem-solving and communication skills. Preferred Skills Experience with Next.js . Experience with GraphQL . Knowledge of Node.js . Experience with cloud platforms such as AWS, Azure, or Google Cloud . Experience with Docker and Kubernetes . Knowledge of UI libraries such as Material UI, Ant Design, Tailwind CSS, or Bootstrap . Experience developing enterprise applications using a microservices architecture . Familiarity with authentication technologies such as OAuth 2.0, OpenID Connect, JWT, and SSO . Experience with accessibility standards such as

WCAG / ADA

. Experience working in large-scale enterprise or regulated environments.

Technology Stack Frontend:

React.js, TypeScript, JavaScript, HTML5, CSS3

State Management:

Redux Toolkit / Context API /

Zustand API:

REST, GraphQL Testing:

Jest, React Testing Library, Cypress /

Playwright Tools:

Git, GitHub/GitLab, Jira Cloud/DevOps:

AWS / Azure / Google Cloud Platform, Docker, Kubernetes, CI/CD Education Bachelor's degree in Computer Science, Engineering, Information Technology , or a related field, or equivalent professional experience.