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name: jb-multi-currency description: | Handle Juicebox V5 multi-currency projects (ETH vs USDC accounting). Use when: (1) building UI that displays currency labels (ETH vs USDC), (2) sending transactions that require currency parameter, (3) configuring fund access limits or accounting contexts for new rulesets, (4) querying project balance/surplus with correct token, (5) debugging "wrong currency" issues in payout or allowance transactions, (6) need currency code constants (NATIVE_CURRENCY=61166, USDC varies by chain), (7) cash out modal shows wrong return currency (ETH instead of USDC), (8) need shared chain constants (names, explorers) across multiple modals. Currency in JBAccountingContext is uint32(uint160(tokenAddress)), NOT 1 or 2. Covers baseCurrency detection, decimal handling, terminal accounting, currency codes, dynamic labels, cash out return display, and shared chain constants patterns.

Juicebox V5 Multi-Currency Support

Problem

Juicebox V5 projects can be denominated in either ETH (baseCurrency=1) or USD (baseCurrency=2). UI components and transactions must use the correct currency value, token address, and display labels. Hardcoding "ETH" or currency=1 causes failures for USDC-based projects.

Context / Trigger Conditions

• UI shows "ETH" when project is USDC-based
• Payout or allowance transaction fails silently
• Fund access limits set with wrong currency
• Currency mismatch between ruleset config and terminal accounting
• Need to display correct currency symbol in forms

Solution

1. Detect Project Currency from Ruleset

// baseCurrency is in ruleset metadata
// 1 = ETH, 2 = USD (USDC)
const baseCurrency = ruleset?.metadata?.baseCurrency || 1
const currencyLabel = baseCurrency === 2 ? 'USDC' : 'ETH'

2. Use Dynamic Currency in Transactions

When calling terminal functions (sendPayoutsOf, useAllowanceOf), use the project's baseCurrency:

// WRONG - hardcoded
args: [projectId, token, amount, 1n, minTokensPaidOut, beneficiary]

// CORRECT - dynamic
args: [projectId, token, amount, BigInt(baseCurrency), minTokensPaidOut, beneficiary]

3. Fund Access Limits Currency

When queuing new rulesets or displaying limits, match the existing project currency. Use correct decimals: Query from ERC20.decimals() or use 18 for native tokens.

import { parseUnits } from 'viem'

// Get currency from existing config
const currency = existingConfig?.baseCurrency || 1

// Get decimals from the token contract (or 18 for native token)
// For USDC: 6 decimals. For native token (ETH): 18 decimals.
const decimals = await getTokenDecimals(tokenAddress, publicClient)

// Use in fund access limit configuration
const payoutLimits = [{
  amount: parseUnits(limitAmount, decimals).toString(),
  currency, // Match project's base currency (1 or 2)
}]

4. Two Different "currency" Concepts (CRITICAL)

Juicebox V5 has TWO different concepts called "currency" that are often confused:

Field	Location	Values	Purpose
baseCurrency	Ruleset metadata	1 = ETH, 2 = USD	Issuance rate calculation
JBCurrencyAmount.currency	Fund access limits	1 = ETH, 2 = USD	Payout/allowance limits
JBAccountingContext.currency	Terminal config	uint32(uint160(token))	Terminal accounting

The currency value in JBAccountingContext is NOT 1 or 2. It's uint32(uint160(tokenAddress)).

// NATIVE_TOKEN (ETH) - same on all chains - from JBConstants.NATIVE_TOKEN
const NATIVE_TOKEN = '0x000000000000000000000000000000000000EEEe'
const NATIVE_CURRENCY = 61166 // uint32(uint160(NATIVE_TOKEN)) = 0x0000EEEe

// USDC addresses and currency codes per chain
const USDC_CONFIG: Record<number, { address: string; currency: number }> = {
  1: {      // Ethereum
    address: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
    currency: 909516616,
  },
  10: {     // Optimism
    address: '0x0b2C639c533813f4Aa9D7837CAf62653d097Ff85',
    currency: 3530704773,
  },
  8453: {   // Base
    address: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913',
    currency: 3169378579,
  },
  42161: {  // Arbitrum
    address: '0xaf88d065e77c8cC2239327C5EDb3A432268e5831',
    currency: 1156540465,
  },
}

How to calculate currency from any token address:

const calculateCurrency = (tokenAddress: string): number => {
  // Take last 4 bytes of address as uint32
  return Number(BigInt(tokenAddress) & BigInt(0xFFFFFFFF))
}

5. Decimal Handling

General rule: Get decimals from ERC20.decimals() for any token. Native tokens (ETH, MATIC, etc.) always use 18 decimals.

Common cases:

• Native token (ETH): 18 decimals
• USDC: 6 decimals
• Most ERC-20s: varies - always query decimals()

import { erc20Abi } from 'viem'

// For native token
const NATIVE_DECIMALS = 18

// For ERC-20 tokens - query the contract
const getTokenDecimals = async (tokenAddress: string, publicClient: PublicClient) => {
  if (tokenAddress === NATIVE_TOKEN) return NATIVE_DECIMALS
  return await publicClient.readContract({
    address: tokenAddress as `0x${string}`,
    abi: erc20Abi,
    functionName: 'decimals',
  })
}

// Shortcut for known tokens (use with caution)
const KNOWN_DECIMALS: Record<string, number> = {
  [NATIVE_TOKEN]: 18,
  // USDC on all chains uses 6 decimals
}

6. Terminal Accounting Contexts

When configuring terminals, set accounting context to match. The currency MUST be derived from the token address.

// ETH-based project
{
  terminal: JB_MULTI_TERMINAL,
  accountingContextsToAccept: [{
    token: NATIVE_TOKEN,        // 0x000000000000000000000000000000000000EEEe
    decimals: 18,
    currency: 61166,            // uint32(uint160(NATIVE_TOKEN)) = 0x0000EEEe
  }]
}

// USDC-based project (example: Ethereum)
{
  terminal: JB_MULTI_TERMINAL,
  accountingContextsToAccept: [{
    token: '0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48',
    decimals: 6,
    currency: 909516616,        // uint32(uint160(USDC_ADDRESS))
  }]
}

WRONG: Using currency: 1 for ETH or currency: 2 for USD RIGHT: Using the calculated uint32 value from the token address

Component Pattern

For React components that handle multiple currencies:

interface ChainData {
  chainId: number
  projectId: number
  baseCurrency: number // 1 = ETH, 2 = USD
  // ... other fields
}

function MyComponent({ chainData }: { chainData: ChainData }) {
  const baseCurrency = chainData?.baseCurrency || 1
  const currencyLabel = baseCurrency === 2 ? 'USDC' : 'ETH'

  return (
    <div>
      <span>Amount: {amount} {currencyLabel}</span>
      {/* Use currencyLabel throughout, never hardcode "ETH" */}
    </div>
  )
}

7. Cash Out Modal Currency Display

When cashing out, users burn project tokens and receive funds in the project's base currency. The modal must show the correct currency for the return amount:

interface CashOutModalProps {
  projectId: string
  tokenAmount: string      // Tokens being burned
  tokenSymbol: string      // e.g., "NANA", "REV"
  estimatedReturn: number  // Amount user will receive
  currencySymbol: 'ETH' | 'USDC'  // CRITICAL: matches project's base currency
}

function CashOutModal({
  tokenAmount,
  tokenSymbol,
  estimatedReturn,
  currencySymbol = 'ETH',  // Default to ETH for backwards compatibility
}: CashOutModalProps) {
  // Format decimals based on currency
  const decimals = currencySymbol === 'USDC' ? 2 : 4

  return (
    <div>
      <div>Burning: {tokenAmount} {tokenSymbol}</div>
      <div>You receive: ~{estimatedReturn.toFixed(decimals)} {currencySymbol}</div>
    </div>
  )
}

Key insight: The component receiving cash out data must pass currencySymbol based on the project's baseCurrency, not hardcode "ETH". For USDC-based projects, show "~5.00 USDC" not "~0.002 ETH".

8. Shared Chain Constants Pattern

Avoid duplicating chain info across modals. Create a shared constants file:

// constants/index.ts
export const CHAINS: Record<number, {
  name: string
  shortName: string
  explorerTx: string
  explorerAddress: string
}> = {
  1: {
    name: 'Ethereum',
    shortName: 'ETH',
    explorerTx: 'https://etherscan.io/tx/',
    explorerAddress: 'https://etherscan.io/address/',
  },
  10: {
    name: 'Optimism',
    shortName: 'OP',
    explorerTx: 'https://optimistic.etherscan.io/tx/',
    explorerAddress: 'https://optimistic.etherscan.io/address/',
  },
  8453: {
    name: 'Base',
    shortName: 'BASE',
    explorerTx: 'https://basescan.org/tx/',
    explorerAddress: 'https://basescan.org/address/',
  },
  42161: {
    name: 'Arbitrum',
    shortName: 'ARB',
    explorerTx: 'https://arbiscan.io/tx/',
    explorerAddress: 'https://arbiscan.io/address/',
  },
}

export const NATIVE_TOKEN = '0x000000000000000000000000000000000000EEEe' as const

Then import in modals:

import { CHAINS, NATIVE_TOKEN } from '../constants'

const chainInfo = CHAINS[chainId] || CHAINS[1]
const explorerLink = `${chainInfo.explorerTx}${txHash}`

Verification

• USDC-based projects display "USDC" labels (not "ETH")
• Cash out modals show return in correct currency (ETH or USDC)
• Transactions use correct currency parameter
• Fund access limits store correct currency
• Balance queries use correct token address

Example

For Artizen (project 6 on Base):

• baseCurrency = 2 (USD)
• Display "USDC" in all labels
• Use USDC token address for balance queries: 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
• Fund access limits use currency: 2

Common Mistakes

1. Hardcoded labels: Using "ETH" string instead of currencyLabel
2. Hardcoded currency: Using 1n instead of BigInt(baseCurrency)
3. Wrong decimals: Using 18 decimals for USDC (should be 6)
4. Token mismatch: Querying with NATIVE_TOKEN for USDC project

Notes

• Default to ETH (baseCurrency=1) if not specified
• JBSwapTerminal accepts any token and swaps to project's base currency
• Cash out returns funds in the project's base currency
• Price feeds convert between currencies when needed

References

• JBMultiTerminal5_1: 0x52869db3d61dde1e391967f2ce5039ad0ecd371c
• JBSwapTerminal: 0x0c02e48e55f4451a499e48a53595de55c40f3574
• JBPrices: 0x6e92e3b5ce1e7a4344c6d27c0c54efd00df92fb6