Senior Frontend Engineer — AI Training & Evaluation

Prolific Academic Ltd; United States; Remote; USD 34,000 - 55,000; Full time

Job summary

Prolific Academic Ltd seeks Senior HTML/CSS Developers to join its Expert Network, helping train AI models and evaluate frontend outputs. You will test, review, and provide feedback on AI-generated markup, ensuring semantic structure, accessibility, and cross-browser compatibility.

The role emphasizes independent, high-quality frontend work, with potential for flexible paid tasks and alignment with Prolific’s data-driven research platform.

Qualifications

• Educational background: a BSc or higher in Computer Science, Software Engineering, Web Development, or related field.
• Real-world experience as a Senior Frontend Developer or UI Engineer specialising in HTML/CSS.
• Ability to independently build complex, responsive layouts and components without relying on frameworks.
• Expert understanding of CSS cascade, specificity, the box model, Flexbox, CSS Grid, accessibility standards (WCAG), and cross-browser compatibility.
• High standard for clean, semantic markup and maintainable CSS, including adherence to BEM, design tokens, and modern CSS standards.

Responsibilities

• Evaluate Code Accuracy: review AI-generated HTML/CSS for functional correctness, semantic structure, and best practices.
• Validate Logic & Reasoning: audit AI explanations for layout solutions to ensure technical soundness.
• Conduct Execution Testing: render model-generated markup in environments to verify visuals and cross-browser behavior.
• Annotate Model Performance: identify inaccessible markup, inefficient selectors, deprecated attributes, or hallucinated CSS properties.
• Refine Technical Logic: provide feedback on responsive design, component architecture, and design system implementation.

Skills

Frontend development

HTML/CSS

UI Engineering

Responsive design

CSS cascade

Flexbox

CSS Grid

Accessibility WCAG

BEM methodology

Education

BSc or higher in Computer Science, Software Engineering, Web Development

Tools

Tailwind CSS

SASS/SCSS

CSS Modules

Browser DevTools

Job description

Prolific Academic Ltd seeks Senior HTML/CSS Developers to join its Expert Network, helping train AI models and evaluate frontend outputs. You will test, review, and provide feedback on AI-generated markup, ensuring semantic structure, accessibility, and cross-browser compatibility.

The role emphasizes independent, high-quality frontend work, with potential for flexible paid tasks and alignment with Prolific’s data-driven research platform.