Numentica LLC - Near Shore - Senior Front-End React Developer

Front-End Developer is needed in Los Angeles, United States.

Client: Numentica LLC

Location: los angeles, CA, us

Contract: Freelance

Job Description

This is a remote position.

Preferred Location: Mexico or South America (Brazil / Argentina / Costa Rica).

We’re seeking a Senior Front-End React Developer to join a dynamic product team building scalable, user-friendly web applications for a fast-growing startup. You’ll collaborate closely with designers, backend engineers, and product managers to deliver high-quality UI experiences that delight users.

Responsibilities

• Develop and maintain responsive, accessible, and performant React applications.
• Build reusable components and front-end libraries using React, TypeScript, and modern state management tools (Redux, Context API, Zustand).
• Integrate with RESTful and GraphQL APIs.
• Optimize application performance and implement best practices for scalability.
• Collaborate with cross-functional teams in an Agile environment.
• Write unit and integration tests using Jest, Cypress, or React Testing Library.
• Participate in code reviews and contribute to technical documentation.

Requirements

• 3–5 years of professional experience in front-end development.
• Strong proficiency in React.js, JavaScript (ES6+), and TypeScript.
• Experience with Next.js, Redux, or equivalent state management.
• Solid understanding of HTML5, CSS3, and modern styling frameworks (Tailwind CSS, Styled Components).
• Familiarity with Git, CI/CD pipelines, and modern build tools (Webpack, Vite).
• Experience with GraphQL and/or REST APIs.
• Strong testing skills with Jest, Cypress, or React Testing Library.
• Fluent English communication and ability to work independently.
• Prior experience working with US-based teams or startups is a plus.

Bonus Skills

• Experience with accessibility standards (WCAG, ARIA).
• Familiarity with Storybook or component-driven development.
• Exposure to cloud platforms (AWS, Vercel, Netlify).

What We Offer

• Opportunity to work with a passionate, fast-moving startup team.
• Potential for long-term engagement and growth.