Track 8 · Capstones · lesson 3

NFT minting dApp

90 min

An NFT collection people can mint from your site. The help steps down now: you get the shape and the signatures, and you write the bodies.

The build

An ERC-721 with a public mint (paid or free, your call), on-chain or IPFS metadata, and a page that mints and shows what the connected wallet owns.

Architecture

contracts/
  NFT.sol        // ERC721 + Ownable, a mint function, a tokenURI
  test/
web/
  Mint.tsx       // mint button + supply counter
  Gallery.tsx    // the connected wallet's tokens, from Transfer events

The signatures — you fill the bodies

function mint() external payable;            // enforce price + max supply
function tokenURI(uint256 id)
    external view returns (string memory);   // metadata per token
function totalMinted() external view returns (uint256);

Decisions the signatures leave to you:

• Metadata: fully on-chain SVG (track 5), or an IPFS base URI. Either is valid; know why you chose it.
• Supply and price: enforce a maximum, and refund or reject overpayment.
• The gallery: read the wallet's tokens from Transfer events (track 6), since ERC-721 has no built-in enumeration.

Acceptance criteria

• Minting past the max supply reverts.
• tokenURI returns valid metadata for a minted id and reverts for an unminted one.
• The gallery shows exactly the connected wallet's tokens and updates after a mint.