Quickstart on BNB Chain

This page takes you from zero to a cross-network swap sourced from BNB Chain. No new contracts, no approval for native BNB, 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 BNB Chain wallet provider

BNB Chain uses the same EvmWalletProvider as every other EVM network, keyed by ChainKeys.BSC_MAINNET.

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

const walletProvider = new EvmWalletProvider({
  privateKey: '0x…',
  chainId: ChainKeys.BSC_MAINNET,
  rpcUrl: 'https://56.rpc.thirdweb.com', // the RPC in the SODAX config
});

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

// walletClient and publicClient are viem clients for BNB Smart Chain,
// 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. On BNB Chain this matters more than usual: USDC and USDT use 18 decimals there, not 6.

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 bnb = bySymbol(sodax.swaps.getSupportedSwapTokensByChainId(ChainKeys.BSC_MAINNET), 'BNB');
const usdcBase = bySymbol(sodax.swaps.getSupportedSwapTokensByChainId(ChainKeys.BASE_MAINNET), 'USDC');

4. Quote and swap

swap() runs the full lifecycle: it creates the intent on BNB Chain, 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 BNB, built from the token's own decimals (18 for BNB)
const inputAmount = 10n ** BigInt(bnb.decimals) / 10n;

// Quote: 0.1 BNB -> USDC on Base
const quoteResult = await sodax.swaps.getQuote({
  token_src: bnb.address,
  token_dst: usdcBase.address,
  token_src_blockchain_id: ChainKeys.BSC_MAINNET,
  token_dst_blockchain_id: ChainKeys.BASE_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: bnb.address,
    outputToken: usdcBase.address,
    inputAmount,
    minOutputAmount: (quoted_amount * 99n) / 100n, // your slippage policy
    deadline: deadlineResult.value,
    allowPartialFill: false,
    srcChainKey: ChainKeys.BSC_MAINNET,
    dstChainKey: ChainKeys.BASE_MAINNET,
    srcAddress: await walletProvider.getWalletAddress(),
    dstAddress: '0x...', // recipient on Base
    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. A few things to know on BNB Chain:

BNB needs no approval. It is the native token. Swapping a BEP-20 token (USDT, BTCB, and the rest) needs an ERC-20 allowance first; see Approvals.
Amounts follow token.decimals. BNB uses 18, and so do USDC and USDT on BNB Chain. quoted_amount is in the destination token’s units: 6 decimals for USDC on Base in this example.
Look tokens up by SODAX symbol. Binance-Peg ETH is ETHB in the SODAX list, not ETH.

Next steps

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

​1. Install

​2. Create a BNB Chain wallet provider

​3. Look up supported tokens

​4. Quote and swap

​Next steps

1. Install

2. Create a BNB Chain wallet provider

3. Look up supported tokens

4. Quote and swap

Next steps