DeFi SDK is an open-source system of smart contracts designed for precise DeFi portfolio accounting. To put it simply, DeFi SDK is the on-chain balanceOf for DeFi protocols.

If you have any questions about DeFi SDK, feel free to reach out to us on our Discord server.

Features

💥Query user assets and debt deposited in DeFi protocols like Maker, Aave, dYdX, etc.

How much debt does 0xdead..beef have on Compound?

📊Get the underlying components of complex derivative ERC20 tokens

How much cUSDC vs ETH does ETHMACOAPY have?

✨Interact with multiple DeFi protocols in a unified way (coming soon)

See What’s next for DeFi SDK

Table of Contents

• Examples
• DeFi SDK architecture
• Addresses
• Supported protocols
• How to add your adapter
• What’s next for DeFi SDK
• Security vulnerabilities

Examples

Find more examples of defi-sdk usage here (web3js, ethers.js).

Fetch Compound debt and collateral

As of now, to get all cTokens along with a user's debt on Compound you need to perform over 10 calls to the Ethereum node to different contracts or rely on a centralized API. With DeFi SDK, you can call

getProtocolBalances('0xdead...beef', ['Compound'])

on the api.zerion.eth smart contract and get all borrowed and supplied tokens

[{
  metadata: {
    name: 'Compound',
    description: 'Decentralized Lending & Borrowing Protocol',
    websiteURL: 'compound.finance',
    iconURL: 'protocol-icons.s3.amazonaws.com/compound.png',
    version: '0'
  },
  adapterBalances: [{
    metadata: {
      adapterAddress: '0x90F0Ed76cfCf75Ccab31A9b4E51782F230aA0747',
      adapterType: 'Asset'
    },
    balances: [{
      base: {
        metadata: {
          token: '0x6C8c6b02E7b2BE14d4fA6022Dfd6d75921D90E4E',
          name: 'Compound Basic Attention Token',
          symbol: 'cBAT',
          decimals: '8'
        },
        amount: '314159265'
      },
      underlying: [{
        metadata: {
          token: '0x0D8775F648430679A709E98d2b0Cb6250d2887EF',
          name: 'Basic Attention Token',
          symbol: 'BAT',
          decimals: '18'
        },
        amount: '6626070040000000000'
      }]
    }]
  },{
      metadata: {
        adapterAddress: '0xD0646777520Aff625F976a8D81b95B5B42cDa1B9',
        adapterType: 'Debt'
      },
      balances: [{
        base: {
          metadata: {
            token: '0x6B175474E89094C44Da98b954EedeAC495271d0F',
            name: 'Dai Stablecoin',
            symbol: 'DAI',
            decimals: '18'
          },
          amount: '1971081500000000000'
        },
        underlying: []
      }]
    }
  ]
}]

Make sense of tokens like UNI-V1 ETH-cDAI

Sometimes, a DeFi token contains several other tokens, and to calculate their price, you need to know their underlying assets. For example, a Uniswap V1 cDAI pool consists of ETH and cDAI. cDAI, in turn, has DAI as an underlying token. With DeFi SDK you can call

// Uniswap V1 cDAI pool
getFinalFullTokenBalance("Uniswap V1 pool token", 0x34E89740adF97C3A9D3f63Cc2cE4a914382c230b)

and fetch the decomposition of UNI-token into ERC20 tokens, like ETH and DAI

0.98 ETH
215.6 DAI

Get account balances across all supported DeFi protocols

In case you want to get account balances across all supported DeFi protocols, you can call

// bankless.zerion.eth portfolio 
getBalances(0x0ef51b7dac3933b8109482e7d910c21848e45da0f) 

and obtain all balances for a given account. The response from the smart-contract will contain information about each of the protocols

100 DAI // collateral on Compound
0.1 ETH // debt on Compound
100 USDC // locked in PoolTogether
213 TUSD + 201 USDC + 82 USDT + 11 DAI // Curve Y pool
...

Get account balances across DeFi protocols that uses liquidity pools

For the protocols that uses a lot of liquidity pools (Bancor, Balancer, Uniswap) balances are not available by default in getBalances() function. Balances for such protocols must be fetched by getAdapterBalance() function with a list of pools passed as a function parameter. If you call

getBalances(
    0x42b9dF65B219B3dD36FF330A4dD8f327A6Ada990, // account address
    0x581Ae5AF7afa6f8171Bbf40d1981779F168A9523, // balancer adapter address
    [0x53b89CE35928dda346c574D9105A5479CB87231c,
        0x987D7Cc04652710b74Fff380403f5c02f82e290a] // balancer pools addresses 
) 

you will obtain Balancer balances for given pools. The response from the smart-contract will contain information about each of the pools

1.3 ETH + 552.4 DAI // 30% WETH + 70% DAI pool
4.2 MKR + 2.5 WETH // 75% MKR + 25% WETH pool

DeFi SDK Architecture

• ProtocolAdapter is a special contract for every protocol. Its main purpose is to wrap all the protocol interactions. There are different types of protocol adapters: "Asset" adapter returns the amount of the account's tokens held on the protocol and the "Debt" adapter returns the amount of the account's debt to the protocol. Some protocols do not use "simple" ERC20 tokens but instead have complex derivatives, for example the Compound protocol has CTokens. The ProtocolAdapter contract also provides information about the type of tokens used within it.
• TokenAdapter is a contract for every derivative token type (e.g cTokens, aTokens, yTokens, etc.) Its main purpose is to provide ERC20-style token metadata as well as information about the underlying ERC20 tokens (like DAI for cDAI). Namely, it provides addresses, types and rates of underlying tokens.
• AdapterRegistry is a contract that a) maintains a list of ProtocolAdapters and TokenAdapters and b) is called to fetch user balances.

More detailed documentation about contracts can be found in adapters and AdapterRegistry documentation.

Addresses

AdapterRegistry contract's mainnet address is 0x06FE76B2f432fdfEcAEf1a7d4f6C3d41B5861672. Its source code is verified on etherscan.

All the deployed contracts' addresses are available here.

Supported Protocols

Protocol Name	Description	Protocol Adapters	Token Adapters
Aave	Decentralized lending & borrowing protocol. Aave market.	Asset adapter Debt adapter	"AToken"
Aave • Uniswap Market	Decentralized lending & borrowing protocol. Uniswap market.	Asset adapter Debt adapter	"AToken Uniswap Market"
Ampleforth	An adaptive money built on sound economics.	Asset adapter	—
Balancer	Non-custodial portfolio manager, liquidity provider, and price sensor.	Asset adapter supports all Balancer pools	"Balancer pool token"
Bancor	Automated liquidity protocol.	Asset adapter supports Bancor pools starting from version 11	"SmartToken"
Compound	Decentralized lending & borrowing protocol.	Asset adapter Debt adapter Governance adapter	"CToken"
Curve	Exchange liquidity pool for stablecoin trading. Supports all pools.	Asset adapter	"Curve pool token"
DDEX • Lending	Decentralized lending and borrowing	Asset adapter	—
DDEX • Margin	Decentralized margin trading	Asset adapter Debt adapter	—
DDEX • Spot	Decentralized trading	Asset adapter	—
DeFi Money Market	Crypto through revenue-producing real world assets.	Asset adapter	"MToken"
dYdX	Decentralized trading platform. All 4 markets (WETH, SAI, USDC, DAI) are supported.	Asset adapter Debt adapter	—
Idle	Yield aggregator for lending platforms.	Asset adapter	"IdleToken"
iearn.finance (v2/v3)	Yield aggregator for lending platforms. Protocol adapter is duplicated for v2 and v3 versions of protocol.	Asset adapter	"YToken"
KyberDAO	Platform that allows KNC token holders to participate in governance.	Asset adapter	—
Chai	A simple ERC20 wrapper over the Dai Savings Protocol.	Asset adapter	"Chai token"
Dai Savings Protocol	Decentralized lending protocol.	Asset adapter	—
Maker Governance	MKR tokens locked on the MakerDAO governance contracts.	Asset adapter	—
Multi-Collateral Dai	Collateralized loans on Maker.	Asset adapter Debt adapter	—
mStable	mStable unifies stablecoins, lending and swapping into one standard.	Asset adapter	"Masset"
PoolTogether	Decentralized no-loss lottery. Supports SAI, DAI, and USDC pools.	Asset adapter	"PoolTogether pool"
Synthetix	Synthetic assets protocol. Asset adapter returns amount of SNX locked as collateral.	Asset adapter Debt adapter	—
TokenSets	Automated asset management strategies.	Asset adapter	"SetToken"
Uniswap V1	Automated liquidity protocol.	Asset adapter supports all Uniswap V1 pools	"Uniswap V1 pool token"
Uniswap V2	Automated liquidity protocol.	Asset adapter supports all Uniswap V2 pools	"Uniswap V2 pool token"
0x Staking	Liquidity rewards for staking ZRX.	Asset adapter	—

How to Add Your Adapter

The full instructions on how to add a custom adapter to the AdapterRegistry contract may be found in our wiki.

If you have questions and/or want to add your adapter to Zerion reach out to us on our Discord server.

What’s Next for DeFi SDK? 🚀

This first version of DeFi SDK is for read-only accounting purposes. Our next step is to introduce Interactive Adapters that allow users to make cross-protocol transactions from a single interface. We are incredibly excited to work with developers, users and the wider DeFi community to make these integrations as secure and accessible as possible. Watch this space, because the “De” in DeFi is about to get a whole lot more user-friendly!

Security Vulnerabilities 🛡

If you discover a security vulnerability within DeFi SDK, please send us an e-mail at inbox@zerion.io. All security vulnerabilities will be promptly addressed.

Dev Notes

This project uses Truffle and web3js for all Ethereum interactions and testing.

Compile contracts

npm run compile

Run tests

npm run test

Run Solidity code coverage

npm run coverage

Currently, unsupported files are ignored.

Run Solidity and JS linters

npm run lint

Currently, unsupported files are ignored.

Run all the migrations scripts

npm run deploy:network, network is either development or mainnet

Verify contract's code on Etherscan

truffle run verify ContractName@0xcontractAddress --network mainnet

License

All smart contracts are released under GNU LGPLv3.