The SDK

TypeScript · JavaScript · Node 20+ · npm i @marketmayhem/sdk

The SDK is the API with the glue done for you. Your key signs in your own process; the API builds and simulates every transaction; the SDK sends the one-time approvals when they’re needed, retries rate limits and brief outages, and waits until each trade is indexed.

import { MarketMayhem } from '@marketmayhem/sdk';

const mm = MarketMayhem.fromPrivateKey(process.env.PRIVATE_KEY);
await mm.buy('0xTOKEN', { spend: '0.05' });

A complete example

A buy, selling half, a launch that burns part of its first buy, and your referral link. It runs on BSC testnet before every release.

// The same jobs with the SDK: approvals, retries and waiting are handled for you.
//   npm i @marketmayhem/sdk
//   PRIVATE_KEY=0x… TOKEN=0x… node sdk.mjs
import { MarketMayhem } from '@marketmayhem/sdk';

const mm = MarketMayhem.fromPrivateKey(process.env.PRIVATE_KEY, { api: process.env.MM_API });
const token = process.env.TOKEN;

// Buy with 0.0005 BNB. Waits until the trade is indexed.
const bought = await mm.buy(token, { spend: '0.0005' });
console.log(bought.explain, '→', bought.status, bought.hash);

// Sell half of what the wallet holds. A first sale's one-time approvals are sent for you.
const sold = await mm.sell(token, { percent: 50 });
console.log(sold.explain, '→', sold.status, sold.hash);

// Launch a token, burning 60% of its first buy.
const launched = await mm.launch({
  name: 'SDK Example', symbol: 'SDKX', marketCapUsd: '15', firstBuy: '0.0003',
  image: 'https://marketmayhem.co/icon-512.png',   // the logo: every launch needs one
  firstBuyTo: [{ wallet: '0x000000000000000000000000000000000000dEaD', pct: 60 }, { wallet: mm.address, pct: 40 }],
});
console.log('launched', launched.url);

// Your referral link.
console.log('your link:', await mm.referralLink());

console.log('RESULT', JSON.stringify({ bought: bought.status, sold: sold.status, token: launched.token }));

Start


`MarketMayhem.fromPrivateKey(key, options?)`	Sign with a key. It never leaves your process.
`MarketMayhem.fromWalletClient(walletClient, options?)`	Sign with any viem wallet: a browser wallet, a hardware wallet, a KMS signer.
`MarketMayhem.readOnly(options?)`	Quotes, tokens, launches and referrals, with no wallet.

Option	Default	Meaning
`api`	`https://marketmayhem.co/api/v1`	The API. Its `/settings` says which chain it’s on.
`rpcUrl`	a public BSC node	Where transactions are sent.
`referrer`	the API’s rule	A registered referrer paid the referral cut on your trades; `null` for nobody.
`apiKey`	—	Your API key: your wallet becomes the default referrer.

Methods

Method	Returns
`buy(token, { spend, slippageBps? })`	`{ hash, status, explain, approvals }`
`sell(token, { amount } or { percent }, slippageBps?)`	the same
`launch({ name, symbol, marketCapUsd, … })`	`{ token, hash, url, explain }`. Every launch option is accepted.
`previewBuy`, `previewSell`, `previewLaunch` (same arguments)	The transaction built and simulated for this wallet, with its `explain`. Sends nothing.
`quote(token, 'buy' \| 'sell', amount)`	the live quote
`token(address)`, `launches({ after?, limit? })`	reads
`watchLaunches({ everyMs?, signal? })`	an async iterator of every new launch
`tx(hash)`, `waitForIndexed(hash)`	where a transaction is
`referrals(address?)`, `referralLink({ address?, path? })`	earnings and links
`settings()`	network, contracts, fees, pairs, limits

The SDK’s types are generated from the API’s own description (openapi.json), so they match what the API sends.