Deploy with Hardhat

NetZero Chain is a standard EVM chain (Shanghai). Whatever you deploy on Ethereum, BNB Chain or Arbitrum deploys here with a network entry and nothing else.

Hardhat

// hardhat.config.js
require("@nomicfoundation/hardhat-toolbox");
 
module.exports = {
  solidity: { version: "0.8.24", settings: { evmVersion: "shanghai" } },
  networks: {
    netzeroTestnet: {
      url: process.env.NZC_RPC ?? "http://127.0.0.1:8545",
      chainId: 20500,
      accounts: [process.env.NZC_TEST_KEY],   // a test key with test-USDn
    },
  },
};

npx hardhat run scripts/deploy.js --network netzeroTestnet

Foundry

forge create --rpc-url http://127.0.0.1:8545 --private-key $NZC_TEST_KEY \
  --evm-version shanghai src/MyContract.sol:MyContract

cast chain-id --rpc-url http://127.0.0.1:8545     # 20500
cast block finalized --rpc-url http://127.0.0.1:8545

Fees

Set nothing special. Libraries read eth_feeHistory and pick a maxFeePerGas above the 1,000 gwei USDn floor. If you set fees by hand, use at least 1,000 gwei plus a small tip. Because USDn is a dollar, the gas cost Hardhat prints is the dollar cost.

Typical deployment costs: about 1 USDn per 4 KB of runtime code. Half of it funds carbon removals.

Verification

Contract verification on the explorer is on the roadmap. Until then, publish source and compiler settings in your repository and reference the deployment transaction.

Differences from Ethereum you might notice

Ethereum	NetZero Chain
`block.coinbase` is the validator/builder	`block.coinbase` is the fee sink `0x…1006`; the proposer is in `extraData`
Base fee is burned	Base fee is distributed (50/40/10)
`finalized` tag lags 2 epochs (~13 min)	`finalized` lags one block (~3 s)
12 s blocks, 30M gas	3 s blocks, 30M gas
Withdrawals in blocks	Withdrawals field carries mining shares (amount always 0); empty before block 29400
`PREVRANDAO` from the beacon chain	`PREVRANDAO` (`difficulty`) is 1 or 2; do not use it for randomness

Everything else, opcodes, precompiles, gas schedule, ABI, tooling, is the same.