bZx Smart Contracts

Overview

bZx Smart Contracts ecosystem is built around two things simple for understanding: Loan orders and Trade orders. Trade order is an order to exchange to move funds between users' accounts. Loan order is an order to the lending platform to take the lender's funds and provide the borrower with that funds directly or indirectly.

Key Smart Contracts

BZx (BZx.sol)

The entry point of the system. This interface is meant to used with the deployed BZxProxy contract (BZxProxy.sol) address.

// js example: 
var bZx = await BZx.at((await BZxProxy.deployed()).address);

Provides users with the abilities to use:

• Order taking functions,
• Trade placing functions,
• Loan maintenance functions,
• Loan health functions.

See also BZxProxy.sol contract.

The next foundational blocks in the ecosystem are top-level contracts modules that provide all needed interfaces to trade using loaned ERC20 tokens.

BZxOrderTaking.sol / BZxOrderTakingOnChain.sol

The key contract is BZxOrderTaking/BZxOrderTakingOnChain that manages order taking and allows users to

• Take the order as trader,
• Take the order as lender,
• Cancel remaining (untaken) loan.

Dev notes: This smart contract is deployed and attached to the system as submodule of BZx and not designed to be used directly. Use BZx.sol and BZxProxy.sol instead.

BZxTradePlacing.sol / BZxTradePlacing0xV2.sol

The important smart contract that give the ability to trade using loaned funds:

• Executes a 0x trade using loaned funds,
• Executes a market order trade using the oracle contract specified in the loan referenced by loanOrderHash.

Dev notes: This smart contract is deployed and attached to the system as submodule of BZx and not designed to be used directly. Use BZx.sol and BZxProxy.sol instead.

BZxLoanHealth.sol

Functions that allow users to close loans, liquidate positions and other related stuff.

Dev notes: This smart contract is deployed and attached to the system as submodule of BZx and not designed to be used directly. Use BZx.sol and BZxProxy.sol instead.

BZxLoanMaintenance.sol

Collateral and profit management functions. Allows users to change amount of collaterals, allows the trader/lender to transfer ownership of the underlying assets in a position to another user and withdraw their profits.

Dev notes: This smart contract is deployed and attached to the system as submodule of BZx and not designed to be used directly. Use BZx.sol and BZxProxy.sol instead.

BZxOrderHistory.sol

Returns information about currently registered orders and loans in the system. Users (traders and lenders) can get their orders and loans by utilizing functions from this smart contract.

Dev notes: This smart contract is deployed and attached to the system as submodule of BZx and not designed to be used directly. Use BZx.sol and BZxProxy.sol instead.

BZxOracle.sol

The key contract is BZxOracle that provides logic for price discovery of ERC20 token pairs, and handle the trading of those pairs through an on-chain mechanism. Uses Kyber Network as a liquidity provider.

The oracle address should be specified in the loan order. See BZxOrderTaking::takeLoanOrder* and BZxTradePlacing::tradePositionWithOracle function for more details.

Other

OracleRegistry.sol

The contract which keeps track of all oracles registered in the system. Oracles added to the bZx network by decentralized governance.

Documention

https://bZxNetwork.github.io/bZx-monorepo/

How to build docs

1. Make sure that node_modules are updated

yarn install

2. Go to smart contracts folder

cd ./packages/contracts/

3. Initialize doxity by installing node modules

cd ./scripts/doxity
npm i

4. Go back to smart contracts folder and build the docs by running

./extra/generate_documentation_doxity.sh