Stack: Next.js, React, TypeScript, Tailwind CSS, Vercel, Supabase, PostgreSQL, Stripe, Resend, Workvivo, AI Models, Agent Orchestration, D3.js, Live Charting, This Site.

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← Work

Ad Marketplace

A two-sided marketplace for physical ad space.

Problem

Buyers who want physical ad space and owners of that space had no direct way to transact — matching, pricing, and payment were three separate manual problems being solved by email and spreadsheets.

Role

Designed and built the marketplace end-to-end: the matching and bidding mechanics, the transaction layer, and the payout pipeline connecting both sides of the deal.

Stack

  • Next.js
  • Supabase
  • Stripe
  • Vercel
  • Live Charting

Architecture

Marketplace state and payment state are kept as one source of truth — a bid or listing change and its financial consequence commit together, not as two systems reconciled after the fact.

  1. Step 1

    Listing & bidding

    Ad space owners list inventory; buyers place bids against real-time availability.

  2. Step 2

    Match engine

    Server-side logic resolves bids against listings and locks the transaction state.

  3. Step 3

    Stripe settlement

    Payment capture and marketplace payout run against the same matched transaction.

  4. Step 4

    Live activity feed

    Bid and match activity streams to both sides via Supabase realtime.

Outcome

A working two-sided marketplace where listing, bidding, and payout are one continuous flow instead of three disconnected manual steps — the kind of system that only has to be built once if the plumbing between payments and marketplace state is done right.