Building new web3 economies.

Nemeos SDK

Nemeos SDK to facilitate integration with the Nemeos platform.

Install

pnpm install nemeos-sdk

Usage

Note: This is a pure ESM package. If you are using CommonJS, you can use a bundler or import using dynamic import().

// ESM / TypeScript
import { NemeosSDK } from 'nemeos-sdk'

// CommonJS
const { NemeosSDK } = await import('nemeos-sdk')

Initialize SDK

Node.js

import * as ethers from 'ethers'
import { NemeosSDK } from 'nemeos-sdk'

const provider = new ethers.JsonRpcProvider(process.env.INFURA_ENDPOINT_WITH_API_KEY)
const wallet = new ethers.Wallet(process.env.WALLET_PRIVATE_KEY, provider)

const nemeosSdk = new NemeosSDK(wallet, {
  enableLogging: true, // Enable logging to the console - Optional, default: `true`
  nemeosBackendEnvironment: NemeosSDK.NemeosBackendEnvironment.Production, // Optional, default: `Production`
})

Browser

Using ethers.js

import * as ethers from 'ethers'
import { NemeosSDK } from 'nemeos-sdk'

const provider = new ethers.BrowserProvider(window.ethereum)
const signer = await provider.getSigner()

const nemeosSdk = new NemeosSDK(signer, {
  enableLogging: true, // Enable logging to the console - Optional, default: `true`
  nemeosBackendEnvironment: NemeosSDK.NemeosBackendEnvironment.Production, // Optional, default: `Production`
})

Using window.ethereum

import { NemeosSDK, getBrowserProvider } from 'nemeos-sdk'

const provider = getBrowserProvider(window.ethereum)
const signer = await provider.getSigner()

const nemeosSdk = new NemeosSDK(signer, {
  enableLogging: true, // Enable logging to the console - Optional, default: `true`
  nemeosBackendEnvironment: NemeosSDK.NemeosBackendEnvironment.Production, // Optional, default: `Production`
})

Nemeos Customer Client

The Nemeos Customer Client is used to interact with the Nemeos backend to manage customer data.

const nemeosCustomerClient = nemeosSdk.getNemeosCustomerClient()

Generate login signature

Trigger a signature request to the wallet. This signature is used to ensure that the customer is the owner of the wallet when interacting with the Nemeos backend.

The signature is valid for a few days.

const loginSignature = await nemeosCustomerClient.requestLoginSignature()

Fetch customer data

Fetch the customer data associated with the wallet address.

const customerData = await nemeosCustomerClient.fetchCustomerData(loginSignature)

Register email

Register the wallet to an email address. This is used to send email notifications and reminders to customers about their loans.

The email address will not be broadcasted on the blockchain. It is only stored in Nemeos backend database.

const emailAddress = 'nemeos-sdk-example@yopmail.com'
await nemeosCustomerClient.registerEmail(loginSignature, emailAddress)

Unregister email

Unregister the wallet from its associated email address. The customer will no longer receive email notifications and reminders.

This will remove the email address from the Nemeos backend database.

await nemeosCustomerClient.unregisterEmail(loginSignature)

Nemeos Pool Client

The Nemeos Pool Client is used to interact with Nemeos pools smart contracts on the blockchain.

const nemeosPoolClient = nemeosSdk.getNemeosPoolClient({
  nemeosPoolAddress: '0x812db15b8Bb43dBA89042eA8b919740C23aD48a3',
  nftCollectionAddress: '0x15cd1cfCd48C06cfC44D433D66C7a9fE06b2C2c3',
  nemeosPoolMode: NemeosSDK.NemeosPoolMode.BuyOpenSea, // Can be `BuyOpenSea` or `DirectMint`
})

Get Pool Balance

Retrieve the current balance of the pool smart contract in native token in wei (if balance is 1 ETH, will return 1000000000000000000).

const poolBalance = await nemeosPoolClient.getPoolBalance()
console.log('Pool Balance:', poolBalance)

Preview a loan

try {
  // Preview loan for Nemeos Pool `BuyOpenSea` mode
  const nftId = '231'
  const loanDurationDays = 61
  const loanData = await nemeosPoolBuyOpenSeaClient.previewLoan(nftId, loanDurationDays)

  // Preview loan for Nemeos Pool `DirectMint` mode
  const loanDurationDays = 61
  const loanData2 = await nemeosPoolDirectMintClient.previewLoan(loanDurationDays)

  console.log('Preview loanData:', loanData)
  console.log('Preview loanData2:', loanData2)
} catch (error) {
  console.error('Preview loan failed!', error.message)
  throw error
}

Click to show type: Loan preview for Nemeos Pool `BuyOpenSea` mode

export type NftLivePriceBuyOpenSeaData = {
  nftFullLivePriceData: {
    /** @example "231" */
    nftId: string
    /** @example "4000000000000000000" */
    openSeaNftPrice: string
    /** @example "4" */
    openSeaNftPriceHuman: string
    /** @example "4" */
    openSeaNftPriceHumanShortRound: string
    /** @example "12686.2" */
    openSeaNftPriceHumanUSD: string
    /** @example "160000000000000003" */
    nemeosOracleNftCollectionFloorPrice: string
    /** @example "0.16" */
    nemeosOracleNftCollectionFloorPriceHuman: string
    /** @example "0.16" */
    nemeosOracleNftCollectionFloorPriceHumanShortRound: string
    /** @example "507.45" */
    nemeosOracleNftCollectionFloorPriceHumanUSD: string
    /** @example "3880000000000000000" */
    proposedUpfrontPaymentGivenPrices: string
    /** @example "3.88" */
    proposedUpfrontPaymentGivenPricesHuman: string
    /** @example "3.88" */
    proposedUpfrontPaymentGivenPricesHumanShortRound: string
    /** @example "12305.61" */
    proposedUpfrontPaymentGivenPricesHumanUSD: string
    /** @example "4000000000000000000" */
    openSeaNftCollectionFloorPrice: string
    /** @example "4" */
    openSeaNftCollectionFloorPriceHuman: string
    /** @example "4" */
    openSeaNftCollectionFloorPriceHumanShortRound: string
    /** @example "12686.2" */
    openSeaNftCollectionFloorPriceHumanUSD: string
    /** @example "3171.55" */
    exchangeRateToUSD: string
    /** @example "120000000000000000" */
    remainingToPayPrice: string
    /** @example "0.12" */
    remainingToPayPriceHuman: string
    /** @example "0.12" */
    remainingToPayPriceHumanShortRound: string
    /** @example "380.59" */
    remainingToPayPriceHumanUSD: string
    /** @example "121464000000000000" */
    remainingToPayPriceWithInterests: string
    /** @example "0.121464" */
    remainingToPayPriceWithInterestsHuman: string
    /** @example "0.121" */
    remainingToPayPriceWithInterestsHumanShortRound: string
    /** @example "385.23" */
    remainingToPayPriceWithInterestsHumanUSD: string
    /** @example "1464000000000000" */
    interestsToPay: string
    /** @example "0.001464" */
    interestsToPayHuman: string
    /** @example "0.001" */
    interestsToPayHumanShortRound: string
    /** @example "4.64" */
    interestsToPayHumanUSD: string
    /** @example "4001464000000000000" */
    totalLoanPrice: string
    /** @example "4.001464" */
    totalLoanPriceHuman: string
    /** @example "4.001" */
    totalLoanPriceHumanShortRound: string
    /** @example "12690.84" */
    totalLoanPriceHumanUSD: string
    /** @example 3 */
    numberOfInstallments: number
    paySchedule: Array<{
      /** @example "3880000000000000000" */
      toPay: string
      /** @example "3.88" */
      toPayHuman: string
      /** @example "3.88" */
      toPayHumanShortRound: string
      /** @example "12305.61" */
      toPayHumanUSD: string
      /** @example "1721947310346" */
      unixTimestampMs: string
      /** @example "Friday, July 26" */
      dateTimeHuman: string
      /** @example "2024-07-25T22:41:50.346Z" */
      dateTimeJSON: string
    }>
  }
  nftPoolLiveData: {
    /** @example "0x3a668917C167dfa823b2816e782704444503078D" */
    nftPoolAddress: string
    /** @example "25" */
    minimalDepositPercent: string
    /** @example "25" */
    minimalDepositPercentHuman: string
    /** @example "7" */
    yearlyInterestPercent: string
    /** @example "7" */
    yearlyInterestPercentHuman: string
    /** @example "5.6000000000000005" */
    yearlyLiquidityProviderProfitsEstimationPercent: string
    /** @example "5.6" */
    yearlyLiquidityProviderProfitsEstimationPercentHuman: string
    /** @example "309586878710840000" */
    availableLiquidity: string
    /** @example "0.30958687871084" */
    availableLiquidityHuman: string
    /** @example "0.31" */
    availableLiquidityHumanShortRound: string
    /** @example "981.87" */
    availableLiquidityHumanUSD: string
    /** @example "0" */
    liquidityLockedInLoans: string
    /** @example "0" */
    liquidityLockedInLoansHuman: string
    /** @example "0" */
    liquidityLockedInLoansHumanShortRound: string
    /** @example "0" */
    liquidityLockedInLoansHumanUSD: string
    /** @example "309586878710840000" */
    totalValueLocked: string
    /** @example "0.30958687871084" */
    totalValueLockedHuman: string
    /** @example "0.31" */
    totalValueLockedHumanShortRound: string
    /** @example "981.87" */
    totalValueLockedHumanUSD: string
    /** @example "3650" */
    maxYearlyLoanRate: string
    /** @example "43200" */
    vestingTimePerBasisPoint: string
    /** @example 0 */
    currentOngoingLoansCount: number
    /** @example 3 */
    allTimeLoansCount: number
  }
}

Click to show type: Loan preview for Nemeos Pool `DirectMint` mode

export type NftLivePriceDirectMintData = {
  nftFullLivePriceData: {
    /** @example "100000000000000000" */
    mintPrice: string
    /** @example "0.1" */
    mintPriceHuman: string
    /** @example "0.1" */
    mintPriceHumanShortRound: string
    /** @example "316.55" */
    mintPriceHumanUSD: string
    /** @example "25000000000000000" */
    proposedUpfrontPaymentGivenPrices: string
    /** @example "0.025" */
    proposedUpfrontPaymentGivenPricesHuman: string
    /** @example "0.025" */
    proposedUpfrontPaymentGivenPricesHumanShortRound: string
    /** @example "79.14" */
    proposedUpfrontPaymentGivenPricesHumanUSD: string
    /** @example "3165.45" */
    exchangeRateToUSD: string
    /** @example "75000000000000000" */
    remainingToPayPrice: string
    /** @example "0.075" */
    remainingToPayPriceHuman: string
    /** @example "0.075" */
    remainingToPayPriceHumanShortRound: string
    /** @example "237.41" */
    remainingToPayPriceHumanUSD: string
    /** @example "76372500000000000" */
    remainingToPayPriceWithInterests: string
    /** @example "0.0763725" */
    remainingToPayPriceWithInterestsHuman: string
    /** @example "0.076" */
    remainingToPayPriceWithInterestsHumanShortRound: string
    /** @example "241.75" */
    remainingToPayPriceWithInterestsHumanUSD: string
    /** @example "1372500000000000" */
    interestsToPay: string
    /** @example "0.0013725" */
    interestsToPayHuman: string
    /** @example "0.001" */
    interestsToPayHumanShortRound: string
    /** @example "4.34" */
    interestsToPayHumanUSD: string
    /** @example "101372500000000000" */
    totalLoanPrice: string
    /** @example "0.1013725" */
    totalLoanPriceHuman: string
    /** @example "0.101" */
    totalLoanPriceHumanShortRound: string
    /** @example "320.89" */
    totalLoanPriceHumanUSD: string
    /** @example 3 */
    numberOfInstallments: number
    paySchedule: Array<{
      /** @example "25000000000000000" */
      toPay: string
      /** @example "0.025" */
      toPayHuman: string
      /** @example "0.025" */
      toPayHumanShortRound: string
      /** @example "79.14" */
      toPayHumanUSD: string
      /** @example "1721946366176" */
      unixTimestampMs: string
      /** @example "Friday, July 26" */
      dateTimeHuman: string
      /** @example "2024-07-25T22:26:06.176Z" */
      dateTimeJSON: string
    }>
  }
  nftPoolLiveData: {
    /** @example "0xf4180C986Aec6f8fAdc6eFe4A0eC237c819AC074" */
    nftPoolAddress: string
    /** @example "25" */
    minimalDepositPercent: string
    /** @example "25" */
    minimalDepositPercentHuman: string
    /** @example "10" */
    yearlyInterestPercent: string
    /** @example "10" */
    yearlyInterestPercentHuman: string
    /** @example "8" */
    yearlyLiquidityProviderProfitsEstimationPercent: string
    /** @example "8" */
    yearlyLiquidityProviderProfitsEstimationPercentHuman: string
    /** @example "100000000000000000" */
    availableLiquidity: string
    /** @example "0.1" */
    availableLiquidityHuman: string
    /** @example "0.1" */
    availableLiquidityHumanShortRound: string
    /** @example "316.55" */
    availableLiquidityHumanUSD: string
    /** @example "0" */
    liquidityLockedInLoans: string
    /** @example "0" */
    liquidityLockedInLoansHuman: string
    /** @example "0" */
    liquidityLockedInLoansHumanShortRound: string
    /** @example "0" */
    liquidityLockedInLoansHumanUSD: string
    /** @example "100000000000000000" */
    totalValueLocked: string
    /** @example "0.1" */
    totalValueLockedHuman: string
    /** @example "0.1" */
    totalValueLockedHumanShortRound: string
    /** @example "316.55" */
    totalValueLockedHumanUSD: string
    /** @example "3650" */
    maxYearlyLoanRate: string
    /** @example "43200" */
    vestingTimePerBasisPoint: string
    /** @example 0 */
    currentOngoingLoansCount: number
    /** @example 0 */
    allTimeLoansCount: number
  }
}

Start a loan

try {
  // Start loan for Nemeos Pool `BuyOpenSea` mode
  const nftId = '224'
  const loanDurationDays = 90
  const tx = await nemeosPoolBuyOpenSeaClient.startLoan(nftId, loanDurationDays)

  // Start loan for Nemeos Pool `DirectMint` mode
  const loanDurationDays = 90
  const whitelistProof = ['0x1234567890123456789012345678901234567890'] // Optional, necessary if there is a whitelist
  const tx2 = await nemeosPoolDirectMintClient.startLoan(loanDurationDays, whitelistProof)

  console.log('Starting loan success! Transaction hash:', tx.hash)
} catch (error) {
  console.error('Starting loan failed!', error.message)
  throw error
}

Retrieve a loan

const nftId = '224'
const loan = await nemeosPoolClient.retrieveLoan(nftId)

Type: Loan

type Loan = {
  /** Borrower address */
  borrower: string
  /** Token ID */
  tokenID: bigint
  /** Amount owed with interest */
  amountOwedWithInterest: bigint
  /** Next payment amount */
  nextPaymentAmount: bigint
  /** Interest amount per payment */
  interestAmountPerPayment: bigint
  /** Loan duration in seconds */
  loanDurationInSeconds: bigint
  /** Start time */
  startTime: bigint
  /** Next payment time */
  nextPaymentTime: bigint
  /** Remaining number of installments */
  remainingNumberOfInstallments: number
  /** Daily interest rate at start */
  dailyInterestRateAtStart: bigint
  /** Is closed */
  isClosed: boolean
  /** Is in liquidation */
  isInLiquidation: boolean
}

Pay the next loan step

try {
  const nftId = '224'
  const tx = await nemeosPoolClient.payNextLoanStep(nftId)

  console.log('Paying next loan step success! Transaction hash:', tx.hash)
} catch (error) {
  console.error('Paying next loan step failed!', error.message)
  throw error
}

---

Build

pnpm build

Tests

Test script

# touch .env, or set the environment variables in the command line
export NODE_ENV=development # to connect to Nemeos backend at http://localhost:3000
export WALLET_PRIVATE_KEY=43ac571235456515454565645445454546123121454848791215488877897123
export INFURA_ENDPOINT_WITH_API_KEY=https://sepolia.infura.io/v3/b3866123121321321231212132131123

node tests/test.mjs

Browser test page

Build the test page and the required dependencies with Parcel

pnpm i --global parcel

parcel tests/browser/index.html

License

The MIT License