Conventional auction websites are traditionally done behind closed doors, but we really wanted to do auctions right. So we made aftr markt, a permission-less auction platform on blockchain that anyone can contribute to and verify on the Ethereum chain. The front-end is a responsive react native app that users can select items to auction, verified by our system. Users can also bid on items with a small transaction fee by staking a portion of their money, reducing fake bids. We also engineered for a blind auction, which reduces the Winner’s curse, and keeps bids as fair and honest as possible.
The backend consists of a Redis caching layer for sub-millisecond latency for repeated requests and a smart contract in Solidity (with Ganache and Truffle) that auctions, bids, dispenses and clears winners for a particular item. The API is served using Python and Flask hosted on a GCP compute engine instance, and also programmatically sends SMS texts using Twilio. This smart contract-blockchain architecture prevents fake listings or stolen goods to be listed and allows transparent transfers, bids and auctions which can be run by any Ethereum node around the world.