Trade Anything, Risk Nothing, Protect Your Data

We're thrilled to announce the launch of our decentralized marketplace for tangible goods on Base. Operating under the working name Universal Market Protocol (UMP), our goal is to leverage smart contracts to build a maximally-decentralized, privacy-preserving marketplace while maintaining the flexibility and security of human oversight. UMP combines automated escrow contracts with reputable community members who can mediate disputes and handle situations that fall outside the scope of smart contracts alone. Learn more and explore UMP here: ump-eth.xyz.

This hybrid approach is inspired by other peer-to-peer cryptocurrency marketplaces like OpenBazaar and Bitcointalk's Collectibles board, where mutually-trusted escrow agents have facilitated secure trades for over a decade. The strength of these systems lies in the reputations of the escrow agents, whose future earning potential outweighs any short-term gains from fraudulent activity. By formalizing this approach through smart contracts while preserving human discretion for dispute resolution, we believe UMP will deliver a marketplace that is efficient, trustworthy and shields data from third parties.

First Test: DEGEN Wassie Stickers

For our alpha test, we’re launching a limited sale of DEGEN Wassie stickers using simplified smart contracts. This alpha test is an MVP which aims to validate the core functionalities of our system, gather user feedback, and identify potential bugs or areas for improvement. We have plans to significantly expand the functionality in the near future.

Here's what you need to know:

• Where to buy: Here!

• Price: 150 DEGEN (or equivalent ETH) for 2 stickers, mailed anywhere in North America, the UK or the EU.

• Total Supply: 50 pairs of stickers (limit 1 pair per mailing address).

• Network: Base Mainnet

• Process: Purchase through our storefront, receive an ERC-1155 token as your receipt, and provide your shipping address via XMTP. Stickers will be mailed within 2 days of receiving the mailing address.

• Terms: Barabazs is acting as the arbiter and will issue a full refund to any buyer who requests it. If the buyer does not settle or dispute their order within 3 weeks, the seller is able to settle the escrow.

• Trust assumptions: By participating in this test, you are trusting that the UMP team has designed this product with transparency and integrity and is not doing a rug pull for ~$150 total. The bigger risk, in our opinion, is that our smart contracts are unaudited. The only token approval required is for users who wish to pay with $DEGEN, who must approve OpenSea’s Seaport 1.6 Contract. Users can also pay with ETH, which requires no token approval.

  We made a video showing how to make your first purchase:

How does UMP work?

UMP’s basic contracts, which we’re showcasing today, enable buyers and sellers to transact safely, with minimal reliance on intermediaries.

At its core, UMP ensures that funds are securely held in an escrow contract until the buyer confirms receipt of their item or a trusted arbiter resolves any disputes

Here’s how it works:

1. Buyers select their desired item, review the terms of the sale, make the payment, and provide shipping details to the seller via XMTP.

2. The funds are held in a 2-of-3 multi-signature escrow smart contract until the transaction is complete.

3. If any issue arises, either party can involve a mutually-trusted arbiter to mediate and resolve the dispute based on the terms of the sale.

Key benefits of UMP include:

• Protection through escrow: Funds are only released when predefined conditions are met.

• Privacy-preserving transactions: Sensitive information remains shielded while maintaining full auditability.

• Low-cost, secure settlement: Efficient transaction processing without compromising security.

• Transparent dispute resolution: Buyers and sellers are both protected by fair, transparent mechanisms.

• Open access: Anyone with a cryptocurrency wallet can immediately start buying and selling.

UMP is designed to be modular and easily expandable. We have ambitious plans to significantly expand the protocol to meet the needs and expectations of users as they arise.

Buyer-Friendly Terms

For this test phase, our terms of service heavily favor buyers. The arbiter is instructed to provide refunds to anyone claiming non-receipt of their stickers. (But please don't abuse this to rug us!)

Privacy Considerations

We recommend using a fresh Ethereum address for purchases.

For maximum privacy, consider:

• Using a VPN

• Using a PO Box for shipping

• Funding your address through privacy-preserving services like 0xbow or Railgun

Note: We only retain mailing addresses for 45 days.

The Team

The current implementation of UMP has been built by two passionate developers:

Nick Bax, a blockchain forensic investigator on a mission to solve trust issues in the crypto space.

Barabazs, a crypto-native engineer with experience in building both on-chain and off-chain [REDACTED], and a proven commitment to FOSS and public goods. Check out his work on GitHub.

More technical details:

UMP utilizes smart contracts to facilitate secure transactions between buyers and sellers. Here's a breakdown of the key components:

1. Storefront Contract: This contract acts as a Seaport contract offerer, utilizing OpenSea's Seaport protocol to safely transfer funds from the buyer to the escrow. Storefront owners can designate an arbiter to arbitrate any disputes which may arise between buyer and seller.

2. ERC-1155 Receipt Tokens: These tokens serve as proof of purchase, outlining the terms of the sale. A storefront can list multiple different ERC-1155 receipts for sale with different prices.

3. Escrow Contract: An escrow smart contract holds funds until the transaction is completed. Buyers can settle the transaction when they receive their item, or initiate a dispute if there are issues. The escrow is “optimistic” which means if the buyer forgets to settle the transaction but doesn’t initiate a dispute, the seller can release funds without interaction by the arbiter after the “settle deadline” expires (3 weeks by default) .

4. XMTP Integration: XMTP allows people to send encrypted messages using their Ethereum addresses as their identity. UMP uses XMTP so that buyers can securely communicate shipping details to sellers and describe any disputes which may arise with their arbiter.

   If you want to get really into the details, check out our GitHub or stop by our Discord.

What's a Seaport Contract Offerer?

A Seaport contract offerer is a smart contract that integrates with OpenSea's Seaport protocol, enabling users to place orders directly via smart contracts instead of through a centralized orderbook. This integration allows for highly customizable and efficient marketplace operations. We're grateful to OpenSea and all of Seaport’s contributors for open-sourcing this powerful tool, which has enabled us to create a seamless retail experience within UMP.

Near Future Plans

1. Open the platform for other users to operate their own storefronts

2. Migrate the front-end to IPFS

3. Introduce advanced features including auctions, complex escrow models, and a robust trust system.

Join Us

We’re building more than a protocol—we’re building a community. Whether you’re a buyer, seller, developer, or enthusiast, we’d love for you to be part of this journey. Join our Discord to share your thoughts, collaborate with others, and help shape the future of decentralized commerce. Please join our Discord channel and follow us on X and Farcaster.