Freelance Design Engineer

Mass Culture is a growth media agency. We help mission-driven scale-ups connect brand and performance so they grow faster, more profitably, and with purpose.

Mass Culture is a paid media agency and growth partner for mission-driven scale-up brands. We build and run our own client portal: the product our clients log into to see their media plans, budget pacing, cross-channel performance, and the reports we deliver.

We're looking for a part-time engineer to build features in it end to end, and to make them look as good as they work.

• Client-facing surfaces: dashboards, widgets, charts, and the report and deck builders. This is what clients see and react to, and it carries the agency's credibility.
• Admin surfaces: the widget builder, plan editor, pacing tools, and configuration panels our team uses every day.
• The data plumbing a feature needs: Postgres schema and migrations, server actions, and connector work against ad-platform APIs.
• Polish passes on surfaces that already work but don't yet feel finished.

What we use

Next.js 16 (App Router), React 19, TypeScript

Supabase — Postgres, Auth, row-level security, BigQuery

Tailwind CSS v4, Radix UI, a token-based design system

• visx
• Editors & interaction
• Tiptap, dnd-kit, Zustand

bun, Vercel

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