,authortheblockcrypto,authorMatteo Leibowitz。

Translator | Qin Xiaofeng

Main points:

Main points:

• Last week, thousands of Ethereum developers, entrepreneurs, and enthusiasts gathered in Colorado, USA, to participate in the ETHDenver hackathon conference;

• With the growing interest in DeFi projects, developers have been trying to use existing resources to provide more value-added services;

• These highlight projects include Delfi, zDai, ETH This Then That, Universal Wallet, and Safe CDP.

Last week (February 15-27), more than 2,000 Ethereum developers, entrepreneurs, and enthusiasts flocked to Denver, Colorado (Mile High City) to participate in the ETHDenver hackathon conference, the largest Ethereum hackathon in the United States. Hackathon conference.

ETHDenver Hackathon The largest blockchain conference on Ethereum, held annually in Denver, USA, the participating members are mainly Ethereum developers, investors, entrepreneurs and enthusiasts; the purpose of this event is not only to promote Ethereum developers Exchange, and try to discover more excellent projects - anyone can submit a project and participate in the award.

It’s worth noting that this year’s ETHDenver conference creators announced that the event uses blockchain technology in almost every aspect: applying to attend, submitting projects, judging, voting, and performing other tasks.

In the past year, the application layer of Ethereum has undergone great innovation, and many new projects are financial applications or protocols. These applications or protocols provide users with new tools to manage and use Ethereum-based currencies or assets. Such applications are known as "decentralized financial services" or "DeFi," and the stablecoin "DAI" is the most widely known product of the DeFi project. Recommended reading compiled by Odaily"Please Answer, Ethereum's 2018"。

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Delfi

Delfi byDelphi(Odaily note:

(Odaily note:DelphiIt is a language integrated development environment under the Windows platform, which supports rapid application development)

In addition, Delfi also provides a metric - which can calculate the "cost of moving ETH/DAI price by 5%" - so as to provide a safe price threshold for quantitative trading.

Delfi is suitable for any application where price feeds need to be objective rather than trustworthy. Currently, the most notable use case is MakerDAO.

MakerDAO is a decentralized autonomous organization and smart contract system on Ethereum, and its product is the stable currency DAI. MakerDAO requires CDP to maintain a 150% mortgage ratio between ETH collateral and borrowed DAI, and CDP is the place in the mortgage system that is responsible for keeping the collateral (Ether). If a user pledges $150 worth of ETH, they can borrow up to $100 in DAI; if the collateralization ratio falls below 150%, a liquidation process will start, confiscating the collateral to repay the user's outstanding debt and fees.

Maintaining sufficient collateral is critical to the stability of the MakerDAO system. Therefore, there must be a monitor that can continuously and accurately monitor the price of ETH. Currently, the reference price for the MakerDAO system is provided by "medianizer". A medianizer is a smart contract that collates price data from multiple external sources. A small number of stakeholders continuously monitor reference prices from multiple external sources and submit updates if the source price differs by more than 1% from the most recently submitted price, or if the price was updated more than 6 hours ago. The medianizer smart contract then takes the median of all submitted prices.

Although the medianizer has been god-like so far, there is still considerable room for improvement.

First, there is an element of trust in price feeds, such as the need to trust the data submitted by a certain number of individuals. While it is highly unlikely that these individuals have close ties to the project, it is theoretically possible that these actors colluded to submit inaccurate data and profit from it. Additionally, price feeds are neither volume-weighted nor updated in real time, so may not always accurately reflect true prices.

Delfi's innovation is to eliminate the element of trust and obtain price information directly from decentralized exchanges - Uniswap, Bancor and Eth2Dai are currently used by Delfi. Secondly, Delfi weights the price according to the transaction volume of each exchange, and updates the price of each block; no matter when, the oracle database can provide accurate ETH/DAI market transaction data graph.

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Safe CDP

Another project inspired by MakerDAO is Safe CDP. It is a cryptoeconomic network that allows CDP owners to protect their collateral from liquidation, thereby reducing capital inefficiencies caused by over-collateralization.

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Source: mkr.tools

opportunity costopportunity cost, Excessive collateral means reduced opportunity cost, which prevents CDP owners from using ETH, selling ETH or borrowing ETH.

Safe CDP is essentially a distributed margin call protocol - if the user's collateral value falls below a certain threshold, Safe CDP can provide a window in which third parties (guarantors) who are economically motivated Collateral can continue to be added.

The system architecture includes three parties: CDP owner, guarantor and Keeper program.

As a CDP owner, you need to enter your CDP ID, select "Secure CDP", and enter the following parameters: Target Collateral (in %), Margin Call Threshold (in %), Margin Call Period (in hours), and Reward (in %). CDP owners need to submit a phone number to receive notifications. After submitting the parameters, you will create a smart contract that manages and controls the CDP.

Guarantors are DAI holders who wish to earn income from their token holdings. Guarantors deposit DAI into the Guarantor Pool, allowing administrators to use it to pay off outstanding debts.

The Keeper program is an off-chain server that automatically notifies the smart contract when the Safe CDP falls below the mortgage ratio. Keeper repays the DAI debt with the guarantor's funds, restoring the collateral ratio to a safe percentage.

The CDP owner will then repay the principal and interest to the guarantor within the agreed time window. If the CDP owner fails to pay the funds, the Safe CDP smart contract will trigger a penalty mechanism that will liquidate some of the CDP owner's collateral to be paid to the guarantor.

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zDai.io

The data of cryptocurrencies such as Bitcoin, Ethereum, and DAI are open and transparent, which also means that as long as there is enough time and energy, data analysis such as Chainalysis (data analysis on the chain) or Neutrino (data analysis acquired by Coinbase Exchange) Third-party analytics agencies such as business operators) can target individuals based on their transaction history—such as disclosing previous purchases, gaining insight into personal wealth, or conducting economic attacks through front-running and reverse trading. Such results will undoubtedly make some people restless .

Privacy coins such as Zcash and Monero attempt to address these issues by obfuscating transaction data, but their weak volatility undercuts their effectiveness as a medium of exchange.

zDai is an implementation of the Burner walletZkSNARKS (Zero Knowledge Proof)The project can provide users with a fast, stable and private exchange medium. Users can directly convert xDai to zDai through the Burner wallet interface, and then hide the transaction amount and transaction parties for transactions.

(Odaily Note: The Burner wallet runs on the xDai sidechain. By scanning the QR code with your mobile phone, you can send DAI to another mobile phone within 5 seconds without downloading any wallet. You can use a web browser to achieve it; the wallet The private key is stored in the cookie without encryption. After the transaction is completed, the private key needs to be destroyed at a very low cost.)

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ETH This Then That（ETTT）

The ETTT project was created by a team of ConsenSys engineers. The project was inspired by "If This Then That", which is a nascent network service platform that uses the conditions of other different platforms to decide whether to execute the next command.

The ETTT project is currently hosted on the Ethereum Rinkeby test network, allowing anyone to connect multiple DeFi applications while writing code. Users only need to select a "trigger" to specify the "operation" they want to perform, and they can rest easy.

trigger:

• "ETH price drop below $X" - ETH price drop below $X;

• "Token transfer occurs" - a token transfer occurs;

• "Every ETH block mined" - every ETH block is mined;

operate:

• "transfer ETH" - transfer ETH;

• "Add collateral to CDP" - add collateral to CDP;

• "Send SMS message" - Send me an SMS message.

While ETTT currently only offers three triggers and actions, the possibilities seem endless. Users can create an action, set up stop-loss (stop loss) and buy-stop (stop buying) order functions, buy or sell a certain amount of cryptocurrency on the Uniswap exchange according to price triggers, and can also be based on compound floating interest rates Take out a loan, or send a text message every time a proposal needs a vote.

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Universal Wallet 

Various problems arise during the process of introducing new users to a crypto ecosystem. Even the friendliest experience requires many steps: setting up a Coinbase account, buying ETH, setting up a MetaMask wallet account, and then transferring ETH from Coinbase to MetaMask.

If users want to store value in a stablecoin like DAI, they have to do more operations, such as exchanging ETH for DAI on a trading platform like Uniswap.

andUniversal Login SDK，WyreandCreate2These action codes.

Users first choose a name for their account and then use Wyre to fund the account with a debit or credit card. The magic of Create2 is that fees are only paid when a transaction occurs. Additionally, Universal Wallet allows users to pay relayers in DAI, which means users don't even need to own ETH.

Relayers are relays that propagate information across chains. Blockchain technology company ConsenSys and Ethereum have developed a BTC Relay that allows Ethereum users to pay with Bitcoin. As a bridge between Ethereum and Bitcoin, BTC Relay provides a tool for developers who want to use Ethereum and smart contract applications to verify Bitcoin transactions.

it's hereit's hereFind the introduction of the above five projects.