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Frontend Code Evaluator - Expert - AI Trainer

$90 per hour

Mercor

Job Description

Job Description

About the job

Mercor connects elite creative and technical talent with leading AI research labs. Headquartered in San Francisco, our investors include Benchmark , General Catalyst , Peter Thiel , Adam D'Angelo , Larry Summers , and Jack Dorsey .

Position: Frontend Engineer — Web Replication Preference Rater
Type: Contract
Compensation: $90/hour
Location: Remote

Role Responsibilities

  • Render a reference page and two candidate replications side by side at desktop width. Judge which is the closer reproduction.
  • Diff layout fidelity in detail, including box model, typography, color, image handling, and overflow.
  • Inspect underlying markup with browser devtools to distinguish genuinely correct replications from those that merely look correct.
  • Evaluate responsive behavior and semantic quality, ensuring proper use of flexbox and grid .
  • Write structured rationales for every judgment, ranking defects by importance in precise language.
  • Flag ties, ambiguous cases, and broken task items rather than forcing a preference.

Qualifications

Must-Have

  • 3+ years of professional web development experience, primarily in frontend or full-stack work.
  • Fluency in hand-written HTML and CSS .
  • Working command of browser devtools .
  • Enough JavaScript to read scripts and understand DOM manipulation.
  • Comfort in a terminal for local server setup.
  • Strong written English and discipline to justify judgments.

Preferred

  • Prior RLHF , preference labeling, or model evaluation work.
  • Code review or technical assessment background.
  • Pixel-perfect design-to-code experience.
  • Web accessibility expertise ( WCAG , ARIA ).
  • Familiarity with LLMs' typical failures in codegen.
  • Web scraping or DOM parsing experience.

Application Process (Takes 20–30 mins to complete)

  • Upload resume
  • AI interview based on your resume
  • Submit form

Resources & Support

PS: Our team reviews applications daily. Please complete your AI interview and application steps to be considered for this opportunity.

#hiringmercor
Vacancy posted 2 days ago
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