@vetro-protocol/gateway

Vetro Protocol gateway actions for viem clients. Mints pegged tokens (VUSD, vetBTC) from whitelisted underlying assets and handles redemptions back out.

Installation

pnpm add @vetro-protocol/gateway viem viem-erc20

Overview

• Two gateways ship by default — the VUSD gateway and the vetBTC gateway — exported as gateways (with address + pegBaseSymbol) and gatewayAddresses (just the addresses).
• deposit mints the pegged token: checks previewDeposit for the expected output, runs an allowance + approval if needed, then calls deposit(tokenIn, amountIn, minPeggedTokenOut, receiver).
• Redemptions follow the gateway's two-step flow: requestRedeem opens a request, redeem finalises it once the optional withdrawal delay has elapsed (or immediately if the caller is on the instant-redeem whitelist), and cancelRedeemRequest aborts an open request.
• Read actions cover everything a UI needs to drive these flows: previews, fee getters, request lookup, treasury / pegged-token addresses, and withdrawal-delay configuration.

Usage

import { deposit, gateways, previewDeposit } from "@vetro-protocol/gateway";
import { createPublicClient, createWalletClient, custom, http } from "viem";
import { hemi } from "viem/chains";

const publicClient = createPublicClient({ chain: hemi, transport: http() });
const walletClient = createWalletClient({
  chain: hemi,
  transport: custom(window.ethereum),
});

const vusdGateway = gateways[0]; // VUSD gateway

// 1. Quote how much VUSD a USDT deposit would mint.
const expectedOut = await previewDeposit(publicClient, {
  address: vusdGateway.address,
  amountIn: 1_000_000n, // 1 USDT (6 decimals)
  tokenIn: "0x...", // USDT address
});

// 2. Deposit (approval handled automatically).
const { emitter, promise } = deposit(walletClient, {
  amountIn: 1_000_000n,
  gatewayAddress: vusdGateway.address,
  minPeggedTokenOut: expectedOut,
  receiver: "0x...",
  tokenIn: "0x...",
});

emitter.on("user-signed-deposit", (hash) => console.log("tx hash:", hash));
emitter.on("deposit-transaction-succeeded", (receipt) =>
  console.log("minted:", receipt),
);

await promise;

The same actions are also available via .extend() factories (gatewayPublicActions(), gatewayWalletActions()) for callers who prefer viem's extension pattern.

API

• Public actions (reads):
  • previewDeposit(client, params) — expected pegged-token output for a deposit.
  • previewRedeem(client, params) — expected underlying output for a redeem.
  • getMintFee(client, params) / getRedeemFee(client, params) — current fees.
  • getMaxWithdraw(client, params) — maximum withdrawable amount.
  • getPeggedToken(client, params) — pegged-token address minted by the gateway.
  • getTreasury(client, params) — treasury address backing the gateway.
  • getRedeemRequest(client, params) — details for a specific redeem request.
  • getWithdrawalDelay(client, params) / getWithdrawalDelayEnabled(client, params) — delay configuration.
  • isInstantRedeemWhitelisted(client, params) — whether an account can bypass the delay.
• Wallet actions (writes): deposit, requestRedeem, redeem, cancelRedeemRequest. Each returns { emitter, promise }.
• gatewayPublicActions() / gatewayWalletActions() — viem extension factories that wire the same actions onto a client via .extend().
• gatewayAbi — the minimal ABI subset used by the package.
• Constants: gateways, gatewayAddresses.
• Types: Gateway, CancelRedeemRequestEvents, DepositEvents, RedeemEvents, RequestRedeemEvents.