The counter

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  Inspirational UI from a role playing game

Inspiration

Until now, an over-the-counter (OTC) deal must happen through two transactions and so requires trust between parties.

That's what happened when a DAO offered me a reward on the Polygon chain. Since most of the liquidity for this reward token was on Ethereum, and to avoid each individual to bridge their rewards, the DAO offered to buy back the token on Polygon and to make by itself the bridge back operation.

This buy back took place over the counter (OTC), in two transactions :

• I sent the reward to the DAO address
• The DAO sent me the token and the amount we agreed on

As you can imagine, the few minutes that occurred between both of them were anxiety inducing for the 2nd transaction could never have happened.

What it does

Here is a smart contract and an UI to fill the trust gap with an atomic swap.

• An OTC smart contract is available to be deployed by one party which also registers their counterpart.
• They settle on the deal parameter by sending ERC20 tokens to a deposit function
• Once it is done they can each agree, otherwise cancel
• If any deposit or withdraw is made before the mutual agreement, the one already agreed is reset
• When a mutual agreement has been acknowledged, deposit are closed and the final withdrawAll can be made

How we built it

• Smart contract written with Vyper
• Tested with Apeworx and pytest
• Truffle react box for the UI, not interactive for now it's only a scaffold

Challenges we ran into

• Settle on the features
• Learn vyper
• Find how to deploy it on various chains
• Time

Accomplishments that we're proud of

• Having a smart contract ready

What we learned

• Vyper
• How to integrate various tools together
• The pattern about smart contract deployement by the end-user

What's next for The counter

• Enchance the smart contract
  • NatSpec
  • Event logging
  • Deposit several types of tokens with one call
  • Add support for ERC721 and ERC1155
• UI fashionned like in a Role Playing Game deal between two players. Include token transfer approval management
• Tokenomics
• Testnet deployements : Polygon, Gnosis, Cronos
• web3 authenticated chat rooms and private threads to bargain over the deals
• Make a Metamask snap out of it

Built With

• apeworx
• pytest
• react
• vyper