Buying and selling

Wallet executes; API indexes the receipt.

Execute buys and sells on-chain first. Then call POST /buy or POST /sell with the tx hash so the API indexes the trade.

ETH on the curve

tsbuySellEth.ts

import { parseEther, parseAbi } from "viem";

const routerAbi = parseAbi([
  "function buy(address curve, uint256 minTokensOut) payable",
  "function sell(address curve, uint256 tokenAmount, uint256 minEthOut)",
]);

// Buy with ETH
await walletClient.writeContract({
  address: "0xf4070f50Aed754c12d781d21de9986742017A2B8" as `0x${string}`,
  abi: routerAbi,
  functionName: "buy",
  args: [curveAddress, minTokensOut],
  value: parseEther("0.1"),
});

// Sell tokens back to the curve (approve Router/curve first if required by your path)
await walletClient.writeContract({
  address: "0xf4070f50Aed754c12d781d21de9986742017A2B8" as `0x${string}`,
  abi: routerAbi,
  functionName: "sell",
  args: [curveAddress, tokenAmount, minEthOut],
});

USDG on the curve (LaunchZap)

Requires LaunchZap configured (0xbb0AC5E8910e525B84c014973F10f5595076D951 when set). Approve USDG to LaunchZap, then:

tsbuySellUsdg.ts

import { parseAbi } from "viem";

const zapAbi = parseAbi([
  "function buyCurveWithUsdg(address curve, uint256 usdgIn, uint256 minWethOut, uint256 minTokensOut, uint24 usdgWethFee) returns (uint256 tokensOut)",
  "function sellCurveForUsdg(address curve, uint256 tokenAmount, uint256 minEthOut, uint256 minUsdgOut, uint24 wethUsdgFee) returns (uint256 usdgOut)",
]);

const usdgWethFee = 3000; // Uniswap V3 pool fee tier used by the zap

await walletClient.writeContract({
  address: "0xbb0AC5E8910e525B84c014973F10f5595076D951" as `0x${string}`,
  abi: zapAbi,
  functionName: "buyCurveWithUsdg",
  args: [curveAddress, usdgIn, minWethOut, minTokensOut, usdgWethFee],
});

Sync the receipt

bashsync-buy.sh

curl -sS -X POST "${API_URL}/buy" \
  -H "authorization: Bearer $JWT" \
  -H "content-type: application/json" \
  -d '{
    "token": "0xToken",
    "amount": "1000000000000000000",
    "txHash": "0x…"
  }'

After graduation, use Uniswap V4 Universal Router for ETH swaps (USDG tab is disabled for V4 tokens in the Trancepad UI). Local Anvil may use SimpleDEX instead.