Web Development Expert - Fully Remote | Upto $90/hr
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 EngineerType: ContractCompensation: $90/hourLocation: Remote
Role Responsibilities
Render a reference page and two candidate replications at ×.
Judge which is the closer reproduction, state by state.
Diff visual fidelity in detail: box model and spacing, typography (family, size, weight, line-height, letter-spacing), color and border treatment, image and asset handling, z-order, and overflow.
Read the source of both attempts and grade construction quality.
Distinguish a replication that is genuinely correct from one that merely looks correct at one viewport.
Test responsiveness.
Identify defects such as a nav bar that looks right at px but collapses at px.
Write specific, evidence-cited justifications for every preference.




Provide detailed explanations like "B nests the article body in a single absolutely-positioned div, so the text overlaps the footer below px, while A uses normal document flow."
Use the "this task is broken" escape hatch with judgment.
Distinguish a task that genuinely cannot be completed from one that is merely hard.
Qualifications
Must-Have
3–8 years of professional web development experience in frontend or full-stack work.
Fluency across web eras, including legacy layouts like used for layout.
Command of hand-written HTML and CSS : semantic markup, flexbox, grid, media queries, and legacy float- and table-based layouts.
Browser DevTools as muscle memory.
Command-line comfort: unzipping an archive, standing up a static local server, and untangling a broken image reference.
Enough JavaScript to read a page's scripts and understand their DOM impact.
Professional written English for task justification.
Preferred
Prior RLHF , preference-labeling, model

📌 Front-End Developer — Global Team, Autonomy (España)
🏢 FUT-URE
📍 España