Blind auction: (sealed bid auction) is a type of auction where all bidders commit their offers in sealed envelopes, without knowing the bids of the other participants. The highest bid wins the auction.

Lottery auction: is a type of auction where the winning bid is determined randomly

How we built it:

It includes 3 main parts:

Contracts:

Leverage Oasis Privacy Layer (OPL) and Sapphire contracts library Utilize Celer's Interchain Messaging <-> Sapphire integration to bridge contracts from Sapphire to other EVM networks

API:

Sync on-chain data from contracts to the Firebase database Expose API to serve data to client dApp

dApp:

Using ethers library to interact with Metamask Adopt Svelte framework and picocss to simplify coding Workflow

Challenges we ran into Oasis Privacy Layer - Sapphire is awesome, Celer's Interchain Messaging (IM) integration is smoothly working. But the testing on remote messagsing is not easy, I didn't find any examples to guide this. Contract verification is quite inconvenient, it couldn't be verified by hardhat tool. Although, Oasis supported hardhat JSON metadata files to verify, but "Payload Too Large" error always happened when submitting on Oasis explorer. Eventually, I could verify by flattening contracts and submitting verification on Oasis explorer.

Accomplishments that we're proud of:

Successfully launched an MPV version of on-chain privacy-preserving auction platform.

What we learned:

Learned more about Oasis architecture, components, Consensus/ParaTime layers as well Explored and deeply understood how Oasis Privacy Layer (OPL) - Sapphire work

What's next:

Offer more auction types Support more token standards ERC1155, ERC20... Support all networks as Oasis integrated Improve UI/UX