Arenswap

Arenswap is a Next.js Arc Testnet transaction utility for supported Circle tokens. It keeps the stable Circle Swap Kit flow intact, adds wallet-signed send and management tools, and verifies transaction outcomes from real receipts, balances, allowances, and transfer events where possible.

Features

• Swap with Circle Swap Kit
• Send Token
• Multi-send
• Transaction History
• Approval Manager
• Faucet Helper / Top-up Guide
• Transaction Receipt Page
• Address Book
• Portfolio + Quick Actions

Project Structure

arenswap/
  frontend/   Next.js app, wallet UI, Circle swap proxy route, Arc Testnet config
  contracts/  Foundry contracts workspace and tests

Vercel builds and deploys from frontend/.

Network And Tokens

Arenswap is Arc Testnet only.

Supported tokens:

• USDC
• EURC
• cirBTC

The app uses canonical Arc Testnet token addresses from the implementation. Do not replace them with placeholder or fake addresses.

Frontend Development

Install dependencies and start the local app:

cd frontend
npm install
npm run dev

The app runs on the Next.js local dev URL shown in the terminal, usually http://localhost:3000.

Build the frontend:

cd frontend
npm run build

Run lint:

cd frontend
npm run lint

Vercel Deployment

Use these Vercel project settings:

Root Directory: frontend
Framework Preset: Next.js
Install Command: npm install
Build Command: npm run build
Output Directory: .next

Required Vercel environment variable:

CIRCLE_KIT_KEY=KIT_KEY:...
NEXT_PUBLIC_WALLETCONNECT_PROJECT_ID=...

CIRCLE_KIT_KEY is server-side only. Do not prefix it with NEXT_PUBLIC_, do not render it in the browser, and do not send it to the wallet. The frontend calls frontend/app/api/circle/swap/route.ts, and that server route calls Circle with the kit key.

NEXT_PUBLIC_WALLETCONNECT_PROJECT_ID is required for mobile wallet connection through WalletConnect and wallet deep links. Get it from WalletConnect/Reown Cloud, add it to local frontend/.env.local, and add it to Vercel Environment Variables. This value is public and safe to expose, unlike CIRCLE_KIT_KEY.

Do not use private keys in this project. Swaps, sends, multi-sends, and revokes are executed by the connected user wallet only.

Transaction Integrity

The app must not mark a transaction successful just because a wallet request was submitted.

For swaps:

• The result card shows approval and swap transaction hashes when available.
• The Arcscan link opens the final swap transaction.
• Transfer events are decoded from the receipt and small service or gas fee transfers are ignored.
• The input token balance must decrease by the real swap input amount.
• The output token balance must increase.

For sends and multi-sends:

• The wallet signs each transfer.
• The app waits for the transaction receipt.
• The app checks the expected ERC-20 Transfer event where possible.
• If a receipt confirms but verification fails, the UI records a verification warning instead of fake success.
• Multi-send currently sends one wallet transaction per recipient. It is not an atomic batch and does not use a batch contract.

For approvals:

• The app shows only the known Circle swap adapter spender from the current configuration.
• Revoke uses approve(spender, 0).
• The app refetches allowance after confirmation and records whether it reached zero.

Verifying Transactions

Use the compact swap status link, Recent Transactions, /tx/[hash] receipt page, and Arcscan links to verify real transaction state. Local history is stored in browser localStorage and is only a convenience cache; Arcscan and receipt data are the source of truth for on-chain state.

Faucet / Top-up

Use the global Faucet shortcut next to the Arc Testnet badge to open Circle Faucet.