Earn

Overview

Earn mode enables users to deposit into DeFi protocols for yield generation and staking. It supports both pre-integrated protocols (Aave, Morpho) and custom contract integrations with arbitrary calldata.

Earn mode includes both deposit and withdrawal tabs. To deep-link users directly into withdrawals, use Withdraw mode.

Quick start

import { Earn } from '0xtrails/widget'

// Open protocol selection — user picks everything
<Earn apiKey="YOUR_API_KEY" />

Pre-configure the destination protocol:

<Earn
  apiKey="YOUR_API_KEY"
  to={{
    recipient: "0xYearnVault",
    currency: "USDC",
    chain: "katana",
    calldata: encodedDepositCalldata,
  }}
  onEarnSuccess={({ sessionId }) => console.log("deposited", sessionId)}
/>

Props

Required

Prop	Type	Description
`apiKey`	`string`	Trails API key

Destination (optional)

Prop	Type	Description
`to.recipient`	`string`	Protocol contract address
`to.token`	`string`	Token to deposit — symbol or contract address
`to.chain`	`ChainIdentifier`	Protocol chain — name, ID, or viem Chain
`to.defaultToken`	`string`	Default token — user can change
`to.defaultChain`	`ChainIdentifier`	Default chain — user can change
`to.amount`	`string \| number`	Fixed deposit amount
`to.calldata`	`string`	ABI-encoded function call to execute after deposit

Source (optional)

The from shape is a discriminated union on paymentMethod. Crypto source (paymentMethod is "CONNECTED_WALLET", "EXCHANGE", "CRYPTO_TRANSFER", or omitted):

Prop	Type	Description
`from.token`	`string`	Source ERC-20 token — symbol or contract address
`from.chain`	`ChainIdentifier`	Source chain
`from.amount`	`string \| number`	Source amount
`from.walletAddress`	`string`	Source wallet (defaults to connected wallet)
`from.exchange`	`string`	Mesh exchange key (e.g. `"coinbase"`). `EXCHANGE` arm only.

Fiat source (paymentMethod is "CREDIT_DEBIT_CARD"):

Prop	Type	Description
`from.currency`	`string`	ISO 4217 fiat code, e.g. `"USD"`, `"EUR"`, `"GBP"`
`from.amount`	`string \| number`	Fiat amount to charge

Payment method (optional)

paymentMethod controls how the user sources funds:

Value	Method
`"CONNECTED_WALLET"`	Connected wallet (default)
`"CRYPTO_TRANSFER"`	QR code / address deposit
`"CREDIT_DEBIT_CARD"`	Fiat on-ramp
`"EXCHANGE"`	CEX transfer

Lifecycle callbacks

Callback	Signature	When it fires
`onEarnStart`	`({ sessionId }) => void`	User begins the deposit flow
`onEarnSuccess`	`({ sessionId }) => void`	Deposit completes successfully
`onEarnError`	`({ sessionId, error }) => void`	Deposit encounters an error

Examples

Protocol selection — user picks everything

import { Earn } from '0xtrails/widget'

<Earn
  apiKey="YOUR_API_KEY"
  onEarnSuccess={({ sessionId }) => console.log("deposited", sessionId)}
/>

Fixed amount protocol deposit

Deposit 1 USDC into Aave V3 on Arbitrum:

import { Earn } from '0xtrails/widget'
import { encodeFunctionData } from 'viem'

const AAVE_POOL = '0x794a61358D6845594F94dc1DB02A252b5b4814aD'
const USDC_ADDRESS = '0xaf88d065e77c8cC2239327C5EDb3A432268e5831'

const supplyCalldata = encodeFunctionData({
  abi: [{
    name: 'supply',
    type: 'function',
    stateMutability: 'nonpayable',
    inputs: [
      { name: 'asset', type: 'address' },
      { name: 'amount', type: 'uint256' },
      { name: 'onBehalfOf', type: 'address' },
      { name: 'referralCode', type: 'uint16' },
    ],
    outputs: [],
  }],
  functionName: 'supply',
  args: [USDC_ADDRESS, 1000000n, '0xUserAddress', 0],
})

<Earn
  apiKey="YOUR_API_KEY"
  to={{
    recipient: AAVE_POOL,
    currency: "USDC",
    chain: "arbitrum",
    amount: "1",
    calldata: supplyCalldata,
  }}
>
  <button>Deposit 1 USDC to Aave</button>
</Earn>

ERC-4626 vault with dynamic amount

Use TRAILS_ROUTER_PLACEHOLDER_AMOUNT when the deposit amount is a parameter and the user selects it:

import { Earn } from '0xtrails/widget'
import { TRAILS_ROUTER_PLACEHOLDER_AMOUNT } from '0xtrails'
import { encodeFunctionData } from 'viem'

const depositCalldata = encodeFunctionData({
  abi: [{
    name: 'deposit',
    type: 'function',
    stateMutability: 'nonpayable',
    inputs: [
      { name: 'assets', type: 'uint256' },
      { name: 'receiver', type: 'address' },
    ],
    outputs: [{ name: 'shares', type: 'uint256' }],
  }],
  functionName: 'deposit',
  args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT, '0xUserAddress'],
})

<Earn
  apiKey="YOUR_API_KEY"
  to={{
    recipient: "0xVaultContract",
    currency: "USDC",
    chain: "base",
    calldata: depositCalldata,
  }}
>
  <button>Deposit to Vault</button>
</Earn>

Use TRAILS_ROUTER_PLACEHOLDER_AMOUNT when:

Deposit amount is a function parameter
User selects the deposit amount
Amount needs to reflect post-swap/bridge output

Do not use it for functions that read balance internally (e.g. depositAll()).

Composable actions (pre-integrated protocols)

For Aave, Compound, Morpho, Yearn, and other natively supported protocols, use composable actions instead of manual calldata encoding:

import { useTrailsSendTransaction, lend, erc20Utils } from '0xtrails'

export function AaveLendButton({ recipient }: { recipient: `0x${string}` }) {
  const { sendTransaction, isPending } = useTrailsSendTransaction({
    actions: [
      lend({
        marketId: 'base-usdc-aave-v3-lending',
        amount: '100',
      }),
    ],
  })

  return (
    <button
      disabled={isPending}
      onClick={() =>
        sendTransaction({
          to: recipient,
          tokenAddress: erc20Utils.USDC.addressOn('base'),
          tokenAmount: '100000000',
        })
      }
    >
      {isPending ? 'Sending...' : 'Supply 100 USDC to Aave'}
    </button>
  )
}

Use useEarnMarkets to discover available market IDs. See Markets and Providers.

Calldata reference

When to use `TRAILS_ROUTER_PLACEHOLDER_AMOUNT`

// Correct — dynamic amount in calldata
encodeFunctionData({
  functionName: 'deposit',
  args: [TRAILS_ROUTER_PLACEHOLDER_AMOUNT, userAddress],
})

// Correct — function reads balance directly, no placeholder needed
encodeFunctionData({
  functionName: 'depositAll',
  args: [userAddress],
})

TRAILS_ROUTER_PLACEHOLDER_AMOUNT is uint256.max internally. Trails replaces it with the actual output amount at execution time.

SDK Documentation

Overview

Quick start

Props

Required

Destination (optional)

Source (optional)

Payment method (optional)

Lifecycle callbacks

Examples

Protocol selection — user picks everything

Fixed amount protocol deposit

ERC-4626 vault with dynamic amount

Composable actions (pre-integrated protocols)

Calldata reference

When to use `TRAILS_ROUTER_PLACEHOLDER_AMOUNT`

See also

​Overview

​Quick start

​Props

​Required

​Destination (optional)

​Source (optional)

​Payment method (optional)

​Lifecycle callbacks

​Examples

​Protocol selection — user picks everything

​Fixed amount protocol deposit

​ERC-4626 vault with dynamic amount

​Composable actions (pre-integrated protocols)

​Calldata reference

​When to use TRAILS_ROUTER_PLACEHOLDER_AMOUNT

​See also

Overview

Quick start

Props

Required

Destination (optional)

Source (optional)

Payment method (optional)

Lifecycle callbacks

Examples

Protocol selection — user picks everything

Fixed amount protocol deposit

ERC-4626 vault with dynamic amount

Composable actions (pre-integrated protocols)

Calldata reference

When to use `TRAILS_ROUTER_PLACEHOLDER_AMOUNT`

See also