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Overview

A complete NFT project with an ERC-721 collection, decentralized marketplace, and EIP-2981 royalty standard. Includes IPFS for metadata storage and Blockscout for browsing.
DifficultyIntermediate
CategoryNFT
ChainsEthereum
ServicesIPFS (port 5001), Blockscout (port 4000)
LicenseApache-2.0

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Quick Start

dokrypt init my-nft --template evm-nft
cd my-nft
dokrypt up
# ✓ ethereum    http://localhost:8545
# ✓ ipfs        http://localhost:5001
# ✓ blockscout  http://localhost:4000

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Generated Files

my-nft
dokrypt.yaml
foundry.toml
README.md
contracts
NFTCollection.sol
Marketplace.sol
Royalty.sol
test
NFTCollection.t.sol
Marketplace.t.sol
Royalty.t.sol
scripts
deploy-nft.js
upload-metadata.js

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Configuration

version: "1"
name: my-nft

chains:
  ethereum:
    engine: anvil
    chain_id: 31337
    block_time: "2s"

services:
  ipfs:
    type: ipfs
    port: 5001
    gateway_port: 8080
  explorer:
    type: blockscout
    chain: ethereum
    port: 4000

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Contracts

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NFTCollection.sol (ERC-721)

Full standalone ERC-721 implementation with minting and metadata. Constructor: 
constructor(
    string memory name,
    string memory symbol,
    string memory baseURI,
    uint256 maxSupply,
    uint256 mintPrice
)
Functions:
FunctionAccessDescription
mint()Public (payable)Mint an NFT at the configured price
safeTransferFrom(from, to, tokenId)PublicTransfer with receiver check
transferFrom(from, to, tokenId)PublicTransfer without receiver check
approve(to, tokenId)PublicApprove transfer
setApprovalForAll(operator, approved)PublicApprove operator for all tokens
setBaseURI(newBaseURI)OwnerUpdate metadata base URI
tokenURI(tokenId)ViewReturns {baseURI}{tokenId}
balanceOf(owner)ViewToken count for address
ownerOf(tokenId)ViewOwner of specific token
Minting Logic:
  • Payment must equal mintPrice
  • Cannot exceed maxSupply
  • Token IDs are sequential starting from 1
Interfaces implemented: IERC721, IERC721Metadata, IERC721Receiver

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Marketplace.sol

Decentralized NFT marketplace with listings, offers, and platform fees. Fee: 2.5% platform fee (250 basis points) on all sales. Functions:
FunctionAccessDescription
listItem(nft, tokenId, price)PublicList an NFT for sale
buyItem(nft, tokenId)Public (payable)Buy a listed NFT
cancelListing(nft, tokenId)SellerCancel a listing
makeOffer(nft, tokenId)Public (payable)Make an offer (ETH attached)
acceptOffer(nft, tokenId, offerer)SellerAccept a specific offer
withdrawOffer(nft, tokenId)OffererWithdraw your offer
withdrawPlatformFees()OwnerWithdraw collected fees
Events: ItemListed, ItemSold, ItemCanceled, OfferMade, OfferAccepted Listing struct: 
struct Listing {
    address seller;
    uint256 price;
    bool active;
}

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Royalty.sol (EIP-2981)

EIP-2981 royalty standard implementation for NFT secondary sales. Functions:
FunctionAccessDescription
setDefaultRoyalty(receiver, basisPoints)OwnerSet default royalty for all tokens
setTokenRoyalty(tokenId, receiver, basisPoints)OwnerOverride royalty for specific token
royaltyInfo(tokenId, salePrice)ViewReturns (receiver, royaltyAmount)
supportsInterface(interfaceId)ViewERC-165 interface detection
Constraints:
  • Maximum royalty: 10% (1000 basis points)
  • Per-token royalties override the default
  • Calculation: royaltyAmount = salePrice * basisPoints / 10000

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IPFS Metadata

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Upload Metadata

npx hardhat run scripts/upload-metadata.js --network localhost

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Metadata Format

{
  "name": "My NFT #1",
  "description": "A unique digital collectible",
  "image": "ipfs://IMAGE_CID",
  "attributes": [
    { "trait_type": "Background", "value": "Blue" },
    { "trait_type": "Rarity", "value": "Rare" }
  ]
}
Upload images and metadata JSON to IPFS, then set the base URI: 
nft.setBaseURI("ipfs://YOUR_METADATA_CID/");
// tokenURI(1) → "ipfs://YOUR_METADATA_CID/1"

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Deployment

npx hardhat run scripts/deploy-nft.js --network localhost
Deploys NFTCollection and Marketplace. Parameters:
  • Collection name, symbol
  • Base URI (IPFS CID)
  • Max supply
  • Mint price (in wei)