Base NFT Launchpad

Gas-optimized NFT collection contract on Base using ERC721A, with three mint phases, dutch auction pricing, Merkle whitelist, and EIP-2981 royalties.

Features

Feature	Implementation
Batch minting	ERC721A — up to 10x gas savings vs ERC721
Whitelist	Merkle proof — no storage cost per address
Presale	ECDSA signature — backend-controlled allow list
Public sale	Dutch auction — price steps down every 5 min
Royalties	EIP-2981 on-chain (5% default)
Reveal	URI hidden until manual reveal by admin
Access control	Role-based (ADMIN, SIGNER) via OpenZeppelin

Mint Phases

CLOSED → WHITELIST (Merkle proof, 0.05 ETH) → PRESALE (signature) → PUBLIC (dutch auction 0.50→0.05)

Dutch Auction

• Start price: 0.50 ETH
• End price: 0.05 ETH
• Step: -0.05 ETH every 5 minutes
• Duration: ~45 minutes to reach floor

Quick Start

forge install
forge test -vvv

Deploy to Base

cp .env.example .env
forge script script/Deploy.s.sol:DeployNFTLaunchpad \
  --rpc-url $BASE_RPC_URL \
  --broadcast \
  --verify

Collection Parameters

• Max supply: 5,555
• Team reserve: 55 (1%)
• Max per wallet: 5
• Royalty: 5% (EIP-2981)

License

MIT