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The TypeScript SDK provides a type-safe, developer-friendly interface for building on Tempo. Built on top of viem, it extends Ethereum tooling with Tempo-specific features like TIP-20 tokens, batch payments, and account abstraction.

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Installation

npm install tempo-viem viem

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Quick Start

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Configure Provider

Connect to Tempo testnet: 
import { createPublicClient, http } from 'viem'
import { tempoTestnet } from 'tempo-viem/chains'

const client = createPublicClient({
  chain: tempoTestnet,
  transport: http('https://rpc.moderato.tempo.xyz')
})

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Get Token Balance

Query TIP-20 token balances: 
import { tip20Abi } from 'tempo-viem/abis'

const balance = await client.readContract({
  address: '0x20c0000000000000000000000000000000000001', // AlphaUSD
  abi: tip20Abi,
  functionName: 'balanceOf',
  args: ['0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb']
})

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Send Transfer

Send a TIP-20 token transfer: 
import { createWalletClient, parseUnits } from 'viem'
import { privateKeyToAccount } from 'viem/accounts'

const account = privateKeyToAccount('0x...')
const wallet = createWalletClient({
  account,
  chain: tempoTestnet,
  transport: http('https://rpc.moderato.tempo.xyz')
})

const hash = await wallet.writeContract({
  address: '0x20c0000000000000000000000000000000000001',
  abi: tip20Abi,
  functionName: 'transfer',
  args: [
    '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb',
    parseUnits('100', 6) // 100 tokens with 6 decimals
  ]
})

const receipt = await client.waitForTransactionReceipt({ hash })

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TIP-20 Tokens

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Transfer with Memo

Include reconciliation data in transfers: 
import { stringToHex, padHex } from 'viem'

const memo = padHex(stringToHex('INV-12345'), { size: 32 })

const hash = await wallet.writeContract({
  address: '0x20c0000000000000000000000000000000000001',
  abi: tip20Abi,
  functionName: 'transferWithMemo',
  args: [
    '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb',
    parseUnits('100', 6),
    memo
  ]
})

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Watch Transfer Events

Listen for incoming transfers: 
const unwatch = client.watchContractEvent({
  address: '0x20c0000000000000000000000000000000000001',
  abi: tip20Abi,
  eventName: 'Transfer',
  onLogs: (logs) => {
    logs.forEach((log) => {
      console.log(`Transfer: ${log.args.from} -> ${log.args.to}: ${log.args.value}`)
    })
  }
})

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Filter by Recipient

Watch transfers to a specific address: 
const unwatch = client.watchContractEvent({
  address: '0x20c0000000000000000000000000000000000001',
  abi: tip20Abi,
  eventName: 'Transfer',
  args: {
    to: '0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb'
  },
  onLogs: (logs) => {
    console.log('Received payment:', logs)
  }
})

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Batch Payments

Send multiple transfers atomically: 
import { tempoTransactionType } from 'tempo-viem'

// Create multiple transfer calls
const calls = [
  {
    to: '0x20c0000000000000000000000000000000000001',
    data: encodeFunctionData({
      abi: tip20Abi,
      functionName: 'transfer',
      args: ['0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb', parseUnits('100', 6)]
    })
  },
  {
    to: '0x20c0000000000000000000000000000000000001',
    data: encodeFunctionData({
      abi: tip20Abi,
      functionName: 'transfer',
      args: ['0x70997970C51812dc3A010C7d01b50e0d17dc79C8', parseUnits('50', 6)]
    })
  }
]

const hash = await wallet.sendTransaction({
  type: tempoTransactionType,
  calls,
  maxFeePerGas: parseGwei('20'),
  maxPriorityFeePerGas: parseGwei('1')
})

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Account Abstraction

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Fee Sponsorship

Pay gas fees for users: 
const hash = await wallet.sendTransaction({
  type: tempoTransactionType,
  calls: [/* user's operations */],
  feeToken: '0x20c0000000000000000000000000000000000001', // Pay fees in AlphaUSD
  from: sponsorAddress, // Sponsor's address
  maxFeePerGas: parseGwei('20'),
  maxPriorityFeePerGas: parseGwei('1')
})

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Scheduled Payments

Set validity windows for transactions: 
const now = Math.floor(Date.now() / 1000)
const oneHourLater = now + 3600

const hash = await wallet.sendTransaction({
  type: tempoTransactionType,
  calls: [/* payment calls */],
  validAfter: now,
  validBefore: oneHourLater,
  maxFeePerGas: parseGwei('20'),
  maxPriorityFeePerGas: parseGwei('1')
})

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Chain Configuration

The SDK includes pre-configured chain definitions: 
import { tempoTestnet, tempoMainnet } from 'tempo-viem/chains'

// Testnet (Moderato)
console.log(tempoTestnet)
// {
//   id: 42431,
//   name: 'Tempo Testnet',
//   network: 'tempo-testnet',
//   nativeCurrency: { name: 'USD', symbol: 'USD', decimals: 6 },
//   rpcUrls: {
//     default: { http: ['https://rpc.moderato.tempo.xyz'] }
//   },
//   blockExplorers: {
//     default: { name: 'Tempo Explorer', url: 'https://explore.tempo.xyz' }
//   }
// }

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Available ABIs

The SDK exports typed ABIs for all Tempo precompiles: 
import {
  tip20Abi,        // TIP-20 token interface
  tip403Abi,       // TIP-403 policy registry
  feeAmmAbi,       // Fee AMM for stablecoin gas
  accountAbi       // Smart account interface
} from 'tempo-viem/abis'

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Error Handling

Handle Tempo-specific errors: 
import { ContractFunctionExecutionError } from 'viem'

try {
  const hash = await wallet.writeContract({
    address: tokenAddress,
    abi: tip20Abi,
    functionName: 'transfer',
    args: [recipient, amount]
  })
} catch (error) {
  if (error instanceof ContractFunctionExecutionError) {
    // Handle insufficient balance, blocked address, etc.
    console.error('Transfer failed:', error.shortMessage)
  }
}

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TypeScript Support

The SDK is fully typed with automatic inference: 
// Return types are automatically inferred
const balance: bigint = await client.readContract({
  address: '0x20c0000000000000000000000000000000000001',
  abi: tip20Abi,
  functionName: 'balanceOf',
  args: ['0x742d35Cc6634C0532925a3b844Bc9e7595f0bEbb']
})

// Event args are strongly typed
client.watchContractEvent({
  address: '0x20c0000000000000000000000000000000000001',
  abi: tip20Abi,
  eventName: 'Transfer',
  onLogs: (logs) => {
    logs.forEach((log) => {
      // log.args.from, log.args.to, log.args.value are all typed
    })
  }
})

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Next Steps

Integration Guide

Step-by-step integration walkthrough

TIP-20 Reference

Complete TIP-20 token specification

Account Abstraction

Learn about Tempo Transactions

Examples

View complete code examples