Quickstart on Base - SODAX Docs

This page takes you from zero to a cross-network swap sourced from Base. No new contracts, no approval for native ETH, one signed transaction for your user.

Building with an AI assistant? Add the SODAX Builders MCP (https://builders.sodax.com/mcp) to Claude, Cursor, or any MCP-capable tool and it can pull live token lists, real quotes, and these docs while it writes your integration.

1. Install

npm install @sodax/sdk @sodax/wallet-sdk-core
# or: pnpm add / yarn add

2. Create a Base wallet provider

Base uses the same EvmWalletProvider as every other EVM network, keyed by ChainKeys.BASE_MAINNET.

import { EvmWalletProvider } from '@sodax/wallet-sdk-core';
import { ChainKeys } from '@sodax/sdk';

const walletProvider = new EvmWalletProvider({
  privateKey: '0x…',
  chainId: ChainKeys.BASE_MAINNET,
  rpcUrl: 'https://mainnet.base.org', // Base public RPC
});

import { EvmWalletProvider } from '@sodax/wallet-sdk-core';

// walletClient and publicClient are viem clients for Base mainnet,
// usually supplied by wagmi from the user's connected EVM wallet
const walletProvider = new EvmWalletProvider({
  walletClient,
  publicClient,
});

Building in React? @sodax/wallet-sdk-react connects EVM wallets for you and hands back a ready-made provider via useWalletProvider. See Wallets.

3. Look up supported tokens

Token addresses and decimals come from the SDK config, so you never hard-code them.

import { Sodax, ChainKeys, type XToken } from '@sodax/sdk';

const sodax = new Sodax();

// find() returns XToken | undefined, so narrow before using the address
const bySymbol = (tokens: readonly XToken[], symbol: string) => {
  const token = tokens.find(t => t.symbol === symbol);
  if (!token) throw new Error(`${symbol} is not a supported swap token`);
  return token;
};

const eth = bySymbol(sodax.swaps.getSupportedSwapTokensByChainId(ChainKeys.BASE_MAINNET), 'ETH');
const usdcArbitrum = bySymbol(sodax.swaps.getSupportedSwapTokensByChainId(ChainKeys.ARBITRUM_MAINNET), 'USDC');

4. Quote and swap

swap() runs the full lifecycle: it creates the intent on Base, verifies the transaction landed, relays it to the hub, and notifies the solver to fill on the destination network.

import type { SolverIntentQuoteRequest } from '@sodax/sdk';

// 0.1 ETH, built from the token's own decimals
const inputAmount = 10n ** BigInt(eth.decimals) / 10n;

// Quote: 0.1 ETH on Base -> USDC on Arbitrum
const quoteResult = await sodax.swaps.getQuote({
  token_src: eth.address,
  token_dst: usdcArbitrum.address,
  token_src_blockchain_id: ChainKeys.BASE_MAINNET,
  token_dst_blockchain_id: ChainKeys.ARBITRUM_MAINNET,
  amount: inputAmount,
  quote_type: 'exact_input',
} satisfies SolverIntentQuoteRequest);

if (!quoteResult.ok) throw new Error('Quote failed');
const { quoted_amount } = quoteResult.value;

// `deadline` is an absolute Unix timestamp; getSwapDeadline turns an offset into one
const deadlineResult = await sodax.swaps.getSwapDeadline(300n); // 5 minutes from now
if (!deadlineResult.ok) throw new Error('Deadline lookup failed');

// Execute
const swapResult = await sodax.swaps.swap({
  params: {
    inputToken: eth.address,
    outputToken: usdcArbitrum.address,
    inputAmount,
    minOutputAmount: (quoted_amount * 99n) / 100n, // your slippage policy
    deadline: deadlineResult.value,
    allowPartialFill: false,
    srcChainKey: ChainKeys.BASE_MAINNET,
    dstChainKey: ChainKeys.ARBITRUM_MAINNET,
    srcAddress: await walletProvider.getWalletAddress(),
    dstAddress: '0x...', // recipient on Arbitrum
    solver: '0x0000000000000000000000000000000000000000',
    data: '0x',
  },
  walletProvider,
  timeout: 120_000,
});

if (swapResult.ok) {
  console.log('Submitted. Hub tx:', swapResult.value.intentDeliveryInfo.dstTxHash);
} else {
  console.error('Swap failed:', swapResult.error);
}

ok means the intent was created, relayed to the hub, and the solver notified, not that it was filled. Poll sodax.swaps.getStatus({ intent_tx_hash: intentDeliveryInfo.dstTxHash }) until the status is SolverIntentStatusCode.SOLVED, which is the only success signal. The main quickstart has the full polling loop, including why NOT_FOUND is not terminal. ETH needs no approval because it is the native token. Swapping an ERC-20 (USDC, cbBTC, and the rest) needs an allowance first; see Approvals. Build every amount from token.decimals: USDC on Base uses 6 and cbBTC uses 8, not 18.

Next steps

Swaps on Base: approvals, fees, manual orchestration.
Money Market on Base: supply and borrow with cross-network collateral.
Full API reference: Swaps in the SDK docs.

​1. Install

​2. Create a Base wallet provider

​3. Look up supported tokens

​4. Quote and swap

​Next steps

1. Install

2. Create a Base wallet provider

3. Look up supported tokens

4. Quote and swap

Next steps