HTML/CSS - Senior Developers - AI Training - Canterbury, UK

Role overview Contribute senior HTML and CSS expertise to the training and evaluation of AI systems that generate frontend code. This is a flexible, task-based participant opportunity: after a short skills assessment, you may be invited to review code, test rendered results, and give structured feedback. Tasks are paid, with rates set according to skills and experience; some require an uninterrupted hour, while many are shorter.

Responsibilities - Assess generated markup and styles for correctness, semantic structure, and adherence to frontend best practices. - Check the technical accuracy of explanations for layout and styling decisions. - Render code and inspect its appearance and behaviour across browsers. - Flag accessibility problems, inefficient selectors, outdated markup, and invalid or unsupported CSS. - Provide clear feedback on responsive layouts, component structure, and design system implementation.

Requirements - A bachelor’s degree or higher in computer science, software engineering, web development, or a related technical discipline. - Professional experience as a senior frontend developer or UI engineer focused on HTML and CSS. - Ability to build complex responsive layouts and components without relying on frameworks or libraries. - Expert knowledge of the CSS cascade, specificity, box model, Flexbox, Grid, WCAG accessibility, and browser compatibility. - Strong standards for semantic HTML and maintainable CSS, including familiarity with BEM, design tokens, and current CSS practices. - Mastery of HTML5 and modern CSS, including custom properties, animation, and current layout techniques.

Nice to have - Experience with Tailwind CSS, Sass/SCSS, CSS Modules, and component-based design systems. - Familiarity with browser developer tools, accessibility audit tools such as axe or Lighthouse, and cross-browser testing services.

Benefits and work setup - Flexible, remote participation, subject to passing a 10–15 minute skills assessment. - Researchers may offer rates of up to $40 per hour, depending on expertise and experience; this is not a guaranteed rate.