React and Next.js Engineer

As a React / Next.js Engineer, you will work remotely on an hourly paid basis to review AI-generated React/Next.js code, frontend architectures, and technical explanations, as well as produce high-quality reference implementations and step-by-step reasoning for complex engineering problems. You will assess solutions for correctness, clarity, accessibility, security, performance, and adherence to the prompt; identify issues in React rendering behavior, state management, SSR/SSG/ISR, routing/data fetching, hydration, caching, and bundle performance; fact-check technical information; write high-quality explanations and model solutions that demonstrate best practices; and rate and compare multiple AI responses based on correctness and reasoning quality.

This fully remote, hourly paid contractor role is with SME Careers, a fast-growing AI data services company and subsidiary of SuperAnnotate that provides AI training data to many of the world’s largest AI companies and foundation model labs—where your frontend expertise will directly help improve the world’s premier AI models used by millions of developers worldwide.

Important: There is no immediate project for this role; however, if qualified, you will be among the first experts we reach out to when relevant opportunities arise. This will also provide you with access to future projects available through our expert network.

Your profile

• Bachelor’s degree or higher in Computer Science, Software Engineering, or a closely related technical field (or equivalent practical experience).
• 4+ years of professional experience building production web applications with React, including at least 2+ years with Next.js (or equivalent SSR framework experience).
• Expert-level proficiency in modern React: hooks, component patterns, state management, memoization, rendering behavior, and testing.
• Strong Next.js fundamentals (Next 13/14+ preferred): App Router, Server Components (where applicable), route handlers, middleware, caching, and deployment patterns.
• Strong understanding of web fundamentals: HTTP, browser rendering, security basics (XSS/CSRF), cookies/sessions, and OAuth flows.
• Performance mindset: bundle optimization, code splitting, image optimization, Core Web Vitals, and profiling.
• Experience with testing and quality: Jest/Vitest, React Testing Library, Playwright/Cypress, linting, CI/CD.
• Minimum C1 English proficiency (written and spoken), with the ability to write clear technical explanations and follow detailed English-language guidelines.
• Proven experience conducting detailed code reviews and enforcing coding standards for maintainability, correctness, and accessibility.
• Previous experience with AI data training, annotation, or evaluating AI-generated technical content is a strong plus.
• Highly detail-oriented and systematic, with a methodical approach to evaluating reasoning quality and identifying subtle issues in complex UI code.

Key responsibilities

• Develop AI Training Content: Create detailed prompts across React/Next.js topics and write high-quality reference answers to guide AI learning.
• Optimize AI Performance: Evaluate and rank AI responses to enhance correctness, clarity, accessibility, and performance.
• Ensure Model Integrity: Test AI models for inaccuracies or unsafe recommendations, validating reliability across real-world use cases.