> For the complete documentation index, see [llms.txt](https://docs.doppler.lol/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.doppler.lol/reference/examples/dynamic-auctions.md).

# Dynamic auctions

Create coins with Doppler's Dutch auction bonding curve, aka Doppler v4

Dynamic auctions are Dutch auctions where the price starts high and descends over time through epochs until buyers purchase or the auction ends.

## Using market cap targets

`saleConfig()` must be called before `withMarketCapRange()`. Note: Do NOT use `poolConfig()` with `withMarketCapRange()` - they are mutually exclusive. Use `poolConfig()` only with `auctionByTicks()` for manual tick configuration.

```typescript
import { DopplerSDK } from '@whetstone-research/doppler-sdk';
import { parseEther, createPublicClient, createWalletClient, http } from 'viem';
import { privateKeyToAccount } from 'viem/accounts';
import { baseSepolia } from 'viem/chains';

const privateKey = process.env.PRIVATE_KEY as `0x${string}`;
const rpcUrl = process.env.RPC_URL ?? baseSepolia.rpcUrls.default.http[0];

async function main() {
  const account = privateKeyToAccount(privateKey);

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

  const walletClient = createWalletClient({
    chain: baseSepolia,
    transport: http(rpcUrl),
    account,
  });

  const sdk = new DopplerSDK({
    publicClient,
    walletClient,
    chainId: baseSepolia.id,
  });

  const params = sdk
    .buildDynamicAuction()
    .tokenConfig({
      name: 'My Token',
      symbol: 'MTK',
      tokenURI: 'https://example.com/token-metadata.json',
    })
    .saleConfig({
      initialSupply: parseEther('1000000000'),
      numTokensToSell: parseEther('500000000'),
      numeraire: '0x4200000000000000000000000000000000000006', // WETH on Base
    })
    .withMarketCapRange({
      marketCap: { start: 500_000, min: 50_000 }, // $500k start, $50k floor
      numerairePrice: 3000, // ETH = $3000 USD
      minProceeds: parseEther('100'),
      maxProceeds: parseEther('5000'),
    })
    .withMigration({
      type: 'uniswapV4',
      fee: 3000,
      tickSpacing: 60,
      streamableFees: {
        lockDuration: 365 * 24 * 60 * 60,
        beneficiaries: [
          { beneficiary: account.address, shares: parseEther('0.95') },
          await sdk.getAirlockBeneficiary(),
        ],
      },
    })
    .withGovernance({ type: 'noOp' })
    .withUserAddress(account.address)
    .build();

  const result = await sdk.factory.createDynamicAuction(params);

  console.log('Hook:', result.hookAddress);
  console.log('Token:', result.tokenAddress);
  console.log('Pool ID:', result.poolId);
}

main();
```

***

## Using raw ticks

```typescript
const params = sdk.buildDynamicAuction()
  .tokenConfig({
    name: 'My Token',
    symbol: 'MTK',
    tokenURI: 'https://example.com/token-metadata.json',
  })
  .saleConfig({
    initialSupply: parseEther('1000000000'),
    numTokensToSell: parseEther('500000000'),
    numeraire: '0x4200000000000000000000000000000000000006',
  })
  .poolConfig({ fee: 3000, tickSpacing: 60 })
  .auctionByTicks({
    startTick: -92103,
    endTick: -69080,
    minProceeds: parseEther('100'),
    maxProceeds: parseEther('5000'),
    duration: 7 * 24 * 60 * 60,
    epochLength: 3600,
  })
  .withMigration({
    type: 'uniswapV4',
    fee: 3000,
    tickSpacing: 60,
    streamableFees: {
      lockDuration: 365 * 24 * 60 * 60,
      beneficiaries: [
        { beneficiary: account.address, shares: parseEther('1') },
      ],
    },
  })
  .withGovernance({ type: 'noOp' })
  .withUserAddress(account.address)
  .build();
```