About Mercato

What is Mercato?

Mercato is a decentralized, local marketplace built on the AT Protocol (ATProto) - the same open protocol that powers Bluesky. It enables neighbors to trade goods, services, and offers without relying on centralized platforms.

How It Works

• Decentralized Identity - Log in with your Bluesky account. Your identity is portable and you own your data.
• Local Discovery - Find items and offers near you using the map-based Discover page.
• Peer-to-Peer - Connect directly with neighbors. Message authors through Bluesky to arrange trades.
• No Middleman - No fees, no algorithms deciding what you see. Just local community commerce.

Technical Stack

• Backend - Rust + WebAssembly running on Cloudflare Workers
• Protocol - AT Protocol (ATProto) with custom Lexicons for marketplace data
• Real-time - WebSocket connections for live feed updates
• Storage - Cloudflare D1 (SQLite) + Durable Objects for state
• Authentication - OAuth 2.0 via ATProto/Bluesky
• Maps - Leaflet.js with OpenStreetMap tiles

Custom Lexicons

Mercato defines its own ATProto lexicons under the xyz.mercato namespace:

• xyz.mercato.listing - Marketplace listings with title, description, price, barter options, and geolocation
• xyz.mercato.comment - Comments on listings

This means your listings are stored in your ATProto repository, giving you full ownership and portability.

Features

• Post offers or requests with photos
• Auto-resize images to stay within ATProto limits
• Speech-to-text for easy listing creation
• Multiple location input modes (GPS, manual coordinates, map picker)
• Real-time feed updates via WebSockets
• Profile hover cards (like Bluesky)
• Map-based discovery with search
• Comments on listings
• Direct messaging via Bluesky integration

Inspiration

Mercato was inspired by Cloudflare's Statusphere demo, which showed how to build ATProto applications on serverless infrastructure. We extended that concept into a full marketplace experience.

Open Source

Mercato is open source and released under CC0. View the code on GitHub.

The Name

Mercato is Italian for "market" - a nod to the vibrant local markets where communities have traded for centuries. The tomato logo represents fresh, local produce and the community spirit of neighborhood commerce.