Deposits

This guide demonstrates complete deposit flows using the unified deposit API, which automatically detects the optimal authorization method (permit vs approval).

The unified deposit API handles three authorization paths automatically:

Permit - Gas-efficient off-chain signature (EIP-2612)
Approval - Standard ERC-20 approval transaction
Already Approved - Direct deposit when allowance exists

Prerequisites

Node.js 22+
Amplify API key from Paxos Labs
SDK initialized with initAmplifySDK()

Installation

Privy
Wagmi
Viem

pnpm add @paxoslabs/amplify-sdk @privy-io/react-auth viem @tanstack/react-query

pnpm add @paxoslabs/amplify-sdk wagmi viem @tanstack/react-query

pnpm add @paxoslabs/amplify-sdk viem

Imports

Privy
Wagmi
Viem

// SDK imports
import {
  prepareDepositAuthorization,
  prepareDeposit,
  isPermitAuth,
  isApprovalAuth,
  isAlreadyApprovedAuth,
  YieldType,
} from "@paxoslabs/amplify-sdk";

// Privy imports
import { usePrivy, useWallets } from "@privy-io/react-auth";

// Viem imports
import { encodeFunctionData } from "viem";
import { mainnet } from "viem/chains";

// SDK imports
import {
  prepareDepositAuthorization,
  prepareDeposit,
  isPermitAuth,
  isApprovalAuth,
  isAlreadyApprovedAuth,
  YieldType,
} from "@paxoslabs/amplify-sdk";

// Wagmi imports
import { useAccount, useWriteContract, useSignTypedData } from "wagmi";

// SDK imports
import {
  initAmplifySDK,
  prepareDepositAuthorization,
  prepareDeposit,
  isPermitAuth,
  isApprovalAuth,
  isAlreadyApprovedAuth,
  YieldType,
} from "@paxoslabs/amplify-sdk";

// Viem imports
import { createWalletClient, createPublicClient, custom, http } from "viem";
import { mainnet } from "viem/chains";

Complete Examples

Privy
Wagmi
Viem

useDeposit Hook

// src/hooks/useDeposit.ts
import { useState, useCallback } from "react";
import { encodeFunctionData } from "viem";
import { mainnet } from "viem/chains";
import {
  prepareDepositAuthorization,
  prepareDeposit,
  isPermitAuth,
  isApprovalAuth,
  isAlreadyApprovedAuth,
  YieldType,
} from "@paxoslabs/amplify-sdk";

declare const usePrivy: () => { sendTransaction: (tx: any) => Promise<string> };
declare const useWallets: () => { wallets: Array<{ address: string; getEthereumProvider: () => Promise<any> }> };

interface DepositParams {
  amount: string;
  depositAsset: `0x${string}`;
  yieldType: YieldType;
}

export function useDeposit() {
  const { sendTransaction } = usePrivy();
  const { wallets } = useWallets();
  const [status, setStatus] = useState<string>("");
  const [isLoading, setIsLoading] = useState(false);

  const deposit = useCallback(
    async ({ amount, depositAsset, yieldType }: DepositParams) => {
      const wallet = wallets[0];
      if (!wallet) {
        throw new Error("Connect a wallet first");
      }

      setIsLoading(true);
      const to = wallet.address as `0x${string}`;

      try {
        const params = {
          yieldType,
          depositAsset,
          depositAmount: amount,
          to,
          chainId: mainnet.id,
        };

        // Step 1: Get authorization method
        setStatus("Checking authorization...");
        const auth = await prepareDepositAuthorization(params);

        // Step 2: Handle based on method using type guards
        if (isPermitAuth(auth)) {
          setStatus("Please sign permit in your wallet...");
          const provider = await wallet.getEthereumProvider();
          const signature = (await provider.request({
            method: "eth_signTypedData_v4",
            params: [
              to,
              JSON.stringify({
                domain: auth.permitData.domain,
                types: auth.permitData.types,
                primaryType: auth.permitData.primaryType,
                message: auth.permitData.message,
              }),
            ],
          })) as `0x${string}`;

          setStatus("Submitting deposit...");
          const prepared = await prepareDeposit({
            ...params,
            signature,
            deadline: BigInt(auth.permitData.message.deadline),
          });

          await sendTransaction({
            chainId: prepared.txData.chainId,
            to: prepared.txData.address,
            data: encodeFunctionData({
              abi: prepared.txData.abi,
              functionName: prepared.txData.functionName,
              args: prepared.txData.args,
            }),
          });
        } else if (isApprovalAuth(auth)) {
          setStatus("Approving token spend...");
          await sendTransaction({
            chainId: mainnet.id,
            to: auth.txData.address,
            data: encodeFunctionData({
              abi: auth.txData.abi,
              functionName: auth.txData.functionName,
              args: auth.txData.args,
            }),
          });

          setStatus("Submitting deposit...");
          const prepared = await prepareDeposit(params);
          await sendTransaction({
            chainId: prepared.txData.chainId,
            to: prepared.txData.address,
            data: encodeFunctionData({
              abi: prepared.txData.abi,
              functionName: prepared.txData.functionName,
              args: prepared.txData.args,
            }),
          });
        } else if (isAlreadyApprovedAuth(auth)) {
          setStatus("Submitting deposit...");
          const prepared = await prepareDeposit(params);
          await sendTransaction({
            chainId: prepared.txData.chainId,
            to: prepared.txData.address,
            data: encodeFunctionData({
              abi: prepared.txData.abi,
              functionName: prepared.txData.functionName,
              args: prepared.txData.args,
            }),
          });
        }

        setStatus("Deposit successful!");
      } catch (error) {
        setStatus(`Error: ${error instanceof Error ? error.message : "Unknown"}`);
        throw error;
      } finally {
        setIsLoading(false);
      }
    },
    [wallets, sendTransaction]
  );

  return { deposit, status, isLoading };
}

Deposit Component

// src/components/DepositForm.tsx
import { useState } from "react";
import { YieldType } from "@paxoslabs/amplify-sdk";
import { useDeposit } from "../hooks/useDeposit";

const USDC_ADDRESS = "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48" as const;

export function DepositForm() {
  const [amount, setAmount] = useState("100");
  const { deposit, status, isLoading } = useDeposit();

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    await deposit({
      amount,
      depositAsset: USDC_ADDRESS,
      yieldType: YieldType.CORE,
    });
  };

  return (
    <form onSubmit={handleSubmit}>
      <label>
        Amount (USDC):
        <input
          type="number"
          value={amount}
          onChange={(e) => setAmount(e.target.value)}
          disabled={isLoading}
          min="0"
          step="0.01"
        />
      </label>
      <button type="submit" disabled={isLoading}>
        {isLoading ? "Processing..." : "Deposit"}
      </button>
      {status && <p>{status}</p>}
    </form>
  );
}

useDeposit Hook

// src/hooks/useDeposit.ts
import { useState, useCallback } from "react";
import { useAccount, useWriteContract, useSignTypedData } from "wagmi";
import {
  prepareDepositAuthorization,
  prepareDeposit,
  isPermitAuth,
  isApprovalAuth,
  isAlreadyApprovedAuth,
  YieldType,
} from "@paxoslabs/amplify-sdk";

interface DepositParams {
  amount: string;
  depositAsset: `0x${string}`;
  yieldType: YieldType;
}

export function useDeposit() {
  const { address, chainId } = useAccount();
  const { writeContractAsync } = useWriteContract();
  const { signTypedDataAsync } = useSignTypedData();
  const [status, setStatus] = useState<string>("");
  const [isLoading, setIsLoading] = useState(false);

  const deposit = useCallback(
    async ({ amount, depositAsset, yieldType }: DepositParams) => {
      if (!address || !chainId) {
        throw new Error("Connect a wallet first");
      }

      setIsLoading(true);

      try {
        const params = {
          yieldType,
          depositAsset,
          depositAmount: amount,
          to: address,
          chainId,
        };

        // Step 1: Get authorization method
        setStatus("Checking authorization...");
        const auth = await prepareDepositAuthorization(params);

        // Step 2: Handle based on method using type guards
        if (isPermitAuth(auth)) {
          setStatus("Please sign permit in your wallet...");
          const signature = await signTypedDataAsync(auth.permitData);

          setStatus("Submitting deposit...");
          const prepared = await prepareDeposit({
            ...params,
            signature,
            deadline: BigInt(auth.permitData.message.deadline),
          });

          await writeContractAsync({
            address: prepared.txData.address,
            abi: prepared.txData.abi,
            functionName: prepared.txData.functionName,
            args: prepared.txData.args,
            account: address,
          });
        } else if (isApprovalAuth(auth)) {
          setStatus("Approving token spend...");
          await writeContractAsync({
            ...auth.txData,
            account: address,
          });

          setStatus("Submitting deposit...");
          const prepared = await prepareDeposit(params);
          await writeContractAsync({
            address: prepared.txData.address,
            abi: prepared.txData.abi,
            functionName: prepared.txData.functionName,
            args: prepared.txData.args,
            account: address,
          });
        } else if (isAlreadyApprovedAuth(auth)) {
          setStatus("Submitting deposit...");
          const prepared = await prepareDeposit(params);
          await writeContractAsync({
            address: prepared.txData.address,
            abi: prepared.txData.abi,
            functionName: prepared.txData.functionName,
            args: prepared.txData.args,
            account: address,
          });
        }

        setStatus("Deposit successful!");
      } catch (error) {
        setStatus(`Error: ${error instanceof Error ? error.message : "Unknown"}`);
        throw error;
      } finally {
        setIsLoading(false);
      }
    },
    [address, chainId, writeContractAsync, signTypedDataAsync]
  );

  return { deposit, status, isLoading };
}

Deposit Component

// src/components/DepositForm.tsx
import { useState } from "react";
import { useAccount } from "wagmi";
import { YieldType } from "@paxoslabs/amplify-sdk";
import { useDeposit } from "../hooks/useDeposit";

const USDC_ADDRESS = "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48" as const;

export function DepositForm() {
  const { isConnected } = useAccount();
  const [amount, setAmount] = useState("100");
  const { deposit, status, isLoading } = useDeposit();

  if (!isConnected) {
    return <p>Please connect your wallet</p>;
  }

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    await deposit({
      amount,
      depositAsset: USDC_ADDRESS,
      yieldType: YieldType.CORE,
    });
  };

  return (
    <form onSubmit={handleSubmit}>
      <label>
        Amount (USDC):
        <input
          type="number"
          value={amount}
          onChange={(e) => setAmount(e.target.value)}
          disabled={isLoading}
          min="0"
          step="0.01"
        />
      </label>
      <button type="submit" disabled={isLoading}>
        {isLoading ? "Processing..." : "Deposit"}
      </button>
      {status && <p>{status}</p>}
    </form>
  );
}

Complete Script

This example uses pure viem without React, suitable for Node.js scripts or vanilla TypeScript applications.

// deposit.ts
import { createWalletClient, createPublicClient, custom, http } from "viem";
import { mainnet } from "viem/chains";
import {
  initAmplifySDK,
  prepareDepositAuthorization,
  prepareDeposit,
  isPermitAuth,
  isApprovalAuth,
  isAlreadyApprovedAuth,
  YieldType,
} from "@paxoslabs/amplify-sdk";

declare const window: { ethereum: any };
declare const process: { env: { AMPLIFY_API_KEY: string } };

// Configuration
const CONFIG = {
  apiKey: process.env.AMPLIFY_API_KEY!,
  depositAsset: "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48" as `0x${string}`, // USDC
  depositAmount: "1000",
  yieldType: YieldType.CORE,
};

async function main() {
  // Step 1: Initialize SDK
  console.log("Initializing SDK...");
  await initAmplifySDK(CONFIG.apiKey);

  // Step 2: Connect wallet
  console.log("Connecting wallet...");
  const ethereum = window.ethereum;
  if (!ethereum) {
    throw new Error("No wallet found");
  }

  const [account] = (await ethereum.request({
    method: "eth_requestAccounts",
  })) as `0x${string}`[];

  const walletClient = createWalletClient({
    account,
    chain: mainnet,
    transport: custom(ethereum),
  });

  const publicClient = createPublicClient({
    chain: mainnet,
    transport: http(),
  });

  // Step 3: Prepare deposit parameters
  const params = {
    yieldType: CONFIG.yieldType,
    depositAsset: CONFIG.depositAsset,
    depositAmount: CONFIG.depositAmount,
    to: account,
    chainId: mainnet.id,
  };

  // Step 4: Get authorization method
  console.log("Checking authorization method...");
  const auth = await prepareDepositAuthorization(params);

  // Step 5: Handle based on method using type guards
  if (isPermitAuth(auth)) {
    console.log("Authorization method: permit");
    console.log("Signing permit...");
    const signature = await walletClient.signTypedData({
      account,
      domain: auth.permitData.domain,
      types: auth.permitData.types,
      primaryType: auth.permitData.primaryType,
      message: auth.permitData.message,
    });

    console.log("Submitting deposit with permit...");
    const prepared = await prepareDeposit({
      ...params,
      signature,
      deadline: BigInt(auth.permitData.message.deadline),
    });

    const permitHash = await walletClient.writeContract({
      address: prepared.txData.address,
      abi: prepared.txData.abi,
      functionName: prepared.txData.functionName,
      args: prepared.txData.args,
      account,
    });

    console.log(`Deposit submitted: ${permitHash}`);
    await publicClient.waitForTransactionReceipt({ hash: permitHash });
    console.log("Deposit confirmed!");
  } else if (isApprovalAuth(auth)) {
    console.log("Authorization method: approval");
    console.log(`Current allowance: ${auth.currentAllowance}`);
    console.log("Sending approval transaction...");

    const approvalHash = await walletClient.writeContract({
      ...auth.txData,
      account,
    });

    console.log(`Approval submitted: ${approvalHash}`);
    await publicClient.waitForTransactionReceipt({ hash: approvalHash });
    console.log("Approval confirmed!");

    console.log("Submitting deposit...");
    const prepared = await prepareDeposit(params);

    const depositHash = await walletClient.writeContract({
      address: prepared.txData.address,
      abi: prepared.txData.abi,
      functionName: prepared.txData.functionName,
      args: prepared.txData.args,
      account,
    });

    console.log(`Deposit submitted: ${depositHash}`);
    await publicClient.waitForTransactionReceipt({ hash: depositHash });
    console.log("Deposit confirmed!");
  } else if (isAlreadyApprovedAuth(auth)) {
    console.log("Authorization method: already_approved");
    console.log(`Existing allowance: ${auth.allowance}`);
    console.log("Submitting deposit directly...");

    const prepared = await prepareDeposit(params);

    const directHash = await walletClient.writeContract({
      address: prepared.txData.address,
      abi: prepared.txData.abi,
      functionName: prepared.txData.functionName,
      args: prepared.txData.args,
      account,
    });

    console.log(`Deposit submitted: ${directHash}`);
    await publicClient.waitForTransactionReceipt({ hash: directHash });
    console.log("Deposit confirmed!");
  }
}

main().catch(console.error);

Running the Script

# Set environment variable
export AMPLIFY_API_KEY=pxl_your_api_key

# Run with tsx or ts-node
npx tsx deposit.ts

Expected Output

Initializing SDK...
Connecting wallet...
Checking authorization method...
Authorization method: permit
Signing permit...
Submitting deposit with permit...
Deposit submitted: 0x1234...
Deposit confirmed!

What the Code Does

Checks authorization method - Determines if permit, approval, or already approved
Handles permit flow - Signs typed data off-chain for gas-efficient authorization
Handles approval flow - Sends approval transaction then deposit
Handles pre-approved - Deposits directly if allowance exists
Reports status - Updates UI with current operation status

Customization

Custom Slippage

const prepared = await prepareDeposit({
  ...params,
  slippage: 100, // 1% instead of default 0.5%
});

Partner Code

const prepared = await prepareDeposit({
  ...params,
  partnerCode: "your_partner_code",
});

Force Approval Flow

const auth = await prepareDepositAuthorization({
  ...params,
  forceMethod: "approval", // Skip permit detection
});

Troubleshooting

Issue	Solution
”SDK not initialized”	Call `initAmplifySDK()` before using hooks
”Connect a wallet first”	Ensure user has connected wallet
Permit signature fails	Token may not support EIP-2612, falls back to approval
Transaction reverts	Check token balance and allowance

For more details on the deposit API, see Deposit Workflow.

Getting started

Origin - Branded Stablecoins

Amplify - Stablecoin Earn

Access - Borrow

USDG0

Prerequisites

Installation

Imports

Complete Examples

useDeposit Hook

Deposit Component

useDeposit Hook

Deposit Component

Complete Script

Running the Script

Expected Output

What the Code Does

Customization

Custom Slippage

Partner Code

Force Approval Flow

Troubleshooting

Getting started

Origin - Branded Stablecoins

Amplify - Stablecoin Earn

Access - Borrow

USDG0

​Prerequisites

​Installation

​Imports

​Complete Examples

​useDeposit Hook

​Deposit Component

​useDeposit Hook

​Deposit Component

​Complete Script

​Running the Script

​Expected Output

​What the Code Does

​Customization

​Custom Slippage

​Partner Code

​Force Approval Flow

​Troubleshooting

Prerequisites

Installation

Imports

Complete Examples

useDeposit Hook

Deposit Component

useDeposit Hook

Deposit Component

Complete Script

Running the Script

Expected Output

What the Code Does

Customization

Custom Slippage

Partner Code

Force Approval Flow

Troubleshooting