React and Next.js Engineer

AI Trainer Jobs; United States; Remote; USD 83,000 - 124,000; Part time

Job summary

AI Trainer Jobs is seeking a React/Next.js Engineer for remote, hourly work to review AI-generated code, frontend architectures, and provide high-quality reference implementations with step-by-step reasoning. You will assess correctness, clarity, accessibility, security, and performance, and rate AI responses based on quality.

The role requires 4+ years building production web apps with React and 2+ years with Next.js, plus strong testing and English proficiency.

Qualifications

• Bachelor’s degree or higher in CS/SE or related field.
• 4+ years building production web apps with React; 2+ years with Next.js.
• Expert-level React: hooks, patterns, state mgmt, rendering, testing.
• Strong Next.js fundamentals: App Router, Server Components, caching.
• Web fundamentals: HTTP, security basics, cookies, OAuth.
• Performance mindset: bundle optimization, Core Web Vitals.
• Testing and quality: Jest/Vitest, RTL, Playwright/Cypress, CI/CD.
• Minimum C1 English proficiency.
• Experience code reviews and coding standards.
• Experience with AI data training or evaluating AI content is a plus.
• Detail-oriented and methodical in evaluating reasoning quality.

Responsibilities

• Review AI-generated React/Next.js code and provide reference implementations.
• Assess solutions for correctness, clarity, accessibility, security, and performance.
• Rate and compare AI responses based on correctness and reasoning quality.

Skills

React expertise

Next.js (2+ years)

Frontend architecture

Performance optimization

Testing (Jest/Vitest, RTL)

Code reviews

Security basics (XSS/CSRF)

English (C1)

Accessibility

AI data training (plus)

Education

Bachelor's degree or higher in CS/SE

Tools

Jest/Vitest

Playwright/Cypress

CI/CD

TypeScript

Job description

Pay: up to $90/hour

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.

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.

Requirements

• 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.

Skills: Next.js, SSR/SSG/ISR, Frontend architecture, React, Code review, Performance Optimization, TypeScript, Debugging, Accessibility (WCAG), English

Open to candidates in: Germany, India, The United States

Interview language: English