Developer Mode

🤔 The Developer's Dilemma

Smart contract developers face a tough choice: expose private keys in .env files for convenience, or deal with the friction of hardware wallets for every test transaction.

❌ .env File Risk

Private keys in plain text, easily leaked through git commits or malware

❌ Hardware Wallet Friction

Manually confirm every transaction during rapid development cycles

❌ API Key Hassle

Copy-paste Etherscan API keys for each new project

🔧 Hardhat Integration

One-line Setup with @arcsign/hardhat-plugin

Install our official Hardhat plugin and start deploying contracts securely. No private keys in your codebase, ever.

// Install the plugin
npm install @arcsign/hardhat-plugin

// hardhat.config.js
require("@nomicfoundation/hardhat-toolbox");
require("@arcsign/hardhat-plugin");

module.exports = {
  solidity: "0.8.20",
  networks: {
    sepolia: {
      url: "https://eth-sepolia.g.alchemy.com/v2/YOUR_KEY",
      chainId: 11155111,
      accounts: [],  // Empty array - ArcSign provides signers
      arcsign: true, // Enable ArcSign for this network
    },
    bscTestnet: {
      url: "https://data-seed-prebsc-1-s1.binance.org:8545",
      chainId: 97,
      accounts: [],
      arcsign: true,
    },
  },
};

💡 Pro Tip

Enable Session Mode in the Dashboard to auto-sign testnet transactions. You'll only need to enter your password once, then deploy freely for 30 minutes!

⚡ Session Mode (Auto-Sign)

Deploy Without Password Prompts

For intensive testnet development, enable Session Mode to auto-sign transactions for 30 minutes. Enter your password once, then deploy freely without interruptions.

🔓 One-Time Unlock

Enter password once to start a 30-minute auto-signing session

🧪 Testnet Only

Auto-sign on Sepolia, Goerli, BSC Testnet, Mumbai, and more

🔒 Mainnet Protected

Mainnet transactions always require manual confirmation

🛡️ Secure Memory

Keys protected with XOR 3-split in memory, auto-cleared on session end

How to Use

Open Developer Mode → Settings tab
Click "Start Session"
Enter your wallet password
Deploy contracts without password prompts for 30 minutes

# With Session Mode active:
$ npx hardhat run scripts/deploy.ts --network sepolia

[ArcSign] ✓ Transaction auto-signed (session active)
Contract deployed to: 0x1234...abcd
Transaction confirmed in block: 10221130

⚠️ Security Note

Session Mode only works for transaction signing (contract deployment, transfers). Message signing (personal_sign) still requires manual approval for security.

🔑 Block Explorer API Keys

Auto-inject Etherscan, BSCScan, and More

Store your Block Explorer API keys in ArcSign once. The Hardhat plugin automatically injects them into your config — no more .env file management.

Etherscan (Ethereum, Sepolia, Goerli)
BSCScan (BNB Chain, Testnet)
PolygonScan (Polygon, Mumbai)
Arbiscan (Arbitrum One, Sepolia)
Optimistic Etherscan (Optimism)
BaseScan (Base)

// No need for this anymore!
// ETHERSCAN_API_KEY=abc123 (in .env)

// ArcSign auto-injects from Developer Mode settings
await hre.run("verify:verify", {
  address: contractAddress,
  constructorArguments: [],
});
// ✓ API key injected automatically

⚠️ Important

API keys are encrypted with your wallet password and stored on your USB. They're never transmitted over the network.

📜 Signing History

Track Every Transaction

Full audit trail of all developer transactions. Click any entry to view on Block Explorer.

Transaction hash, timestamp, and network
One-click links to Etherscan, BSCScan, etc.
Persistent storage across sessions
Filter by network or time range

🌐 Supported Signing Methods

✍️ personal_sign (EIP-191)

Login authentication, off-chain signatures, message verification

🔏 eth_signTypedData (EIP-712)

Permit tokens, Gasless approvals, Meta-transactions, NFT marketplace listings

💸 eth_sendTransaction

Contract deployment, Token transfers, DeFi interactions

              💡 Common Use Cases
              personal_sign — "Sign in with Ethereum" login, proving wallet ownership
EIP-712 — Uniswap Permit2, OpenSea listings, gasless token approvals
sendTransaction — Deploy contracts, swap tokens, stake assets

            