Visual Royalties Manager
Automate royalty payments to artists via smart contracts every time artwork changes hands.
Sepolia smart contract· onchain logic
Section · Onchain
full primer →The primitive.
Artist royalty automation gets a tiny Solidity contract deployed to Ethereum Sepolia; painters see a 'verified onchain' badge with the live contract address and a one-tap Etherscan link.
Why this primitiveSepolia contracts enforce automatic royalty splits transparently and reliably.
Kernel
a Solidity contract deployed to Ethereum Sepolia via MetaMask private key, then verified on Etherscan
Drives the UI as
a 'verified onchain' badge with the live contract address and an Etherscan link
Required keys.
Add these in your Lovable project under Settings → Secrets before pasting the prompt below.
Appendix · Mega-prompt
The build prompt.
budget · 1 message
Paste into a fresh Lovable project. Make sure all five secrets above are set first. read the build strategy →
Build "Visual Royalties Manager" in ONE Lovable message. Single-page demo.
CONCEPT
Automate royalty payments to artists via smart contracts every time artwork changes hands.
Discipline: Visual Art (artist royalty automation).
Onchain primitive: Sepolia smart contract. Why this primitive: Sepolia contracts enforce automatic royalty splits transparently and reliably.
5-CREDIT BUDGET (HARD LIMIT):
- ONE single-page app. No router, no Lovable Cloud, no database, no auth flows beyond Privy drop-in.
- ONE Solidity contract, <=80 lines, deployed to Sepolia, verified on Etherscan.
- Privy is always the auth + sponsored-tx layer (Google login, embedded wallet).
- Pinata/IPFS only if the idea genuinely needs to store a file or metadata.
- At most ONE AI call per user action (use Lovable AI Gateway with LOVABLE_API_KEY if AI is part of the idea).
- Skip tests, skip CI, skip docs pages. Ship the demo, nothing else.
STACK
- React + Vite single page (the index route).
- SSR-safe Privy mount is mandatory. Never import @privy-io/react-auth at
module scope of a route file — it crashes SSR. Use
lazy(() => import('./privy-client-entry')) inside <ClientOnly> + <Suspense>,
and put <PrivyProvider> only inside privy-client-entry.tsx.
- PrivyProvider config (do NOT stub defaultChain as { id, name } — omit it
or pass viem's `sepolia`; chainId is passed per-call):
<PrivyProvider appId={import.meta.env.VITE_PRIVY_APP_ID}
config={{ loginMethods:['google','email'],
embeddedWallets:{ ethereum:{ createOnLogin:'users-without-wallets' } },
appearance:{ theme:'dark' } }}>
- Read the embedded wallet from useWallets, not user.wallet:
const embedded = wallets.find(w => w.walletClientType === 'privy');
- Every send goes through Privy `useSendTransaction` with BOTH `address`
and `sponsor`, wrapped in a 45s Promise.race timeout whose reject message
names the exact dashboard toggles:
await Promise.race([
sendTransaction(
{ to, data, chainId: 11155111 },
{ address: embedded.address, sponsor: true }
),
new Promise((_, r) => setTimeout(() => r(new Error(
"Privy sendTransaction timed out after 45s. Enable Gas sponsorship -> App pays -> Ethereum Sepolia -> Allow transactions from the client."
)), 45_000)),
]);
- Do NOT pass uiOptions:{ showWalletUIs:false } — it aborts with
"signal is aborted without reason". The approval sheet still shows on
the embedded-EOA path; the fee reads US$0.00.
- Do NOT add ZeroDev / SmartWalletsProvider / a paymaster URL. Native
Privy sponsorship on Sepolia works with the toggles above and nothing else.
- DASHBOARD PREREQUISITE (one-time): Privy dashboard -> Gas sponsorship
-> App pays -> add "Ethereum Sepolia" -> toggle "Allow transactions
from the client" ON. Without this, sendTransaction hangs silently.
- Hardhat in /contracts (kept outside the Vite bundle). Install
`@nomicfoundation/hardhat-toolbox` AND `@nomicfoundation/hardhat-verify@latest`
(>=3.x — older versions still hit Etherscan v1 and fail with
"You are using a deprecated V1 endpoint, switch to Etherscan API V2").
- hardhat.config.cjs MUST use the Etherscan v2 single-key shape (NOT the per-network map):
require("@nomicfoundation/hardhat-toolbox");
require("@nomicfoundation/hardhat-verify");
module.exports = {
solidity: { version: "0.8.24", settings: { optimizer: { enabled: true, runs: 200 } } },
networks: { sepolia: {
url: process.env.SEPOLIA_RPC_URL || "https://ethereum-sepolia-rpc.publicnode.com",
accounts: [process.env.METAMASK_PRIVATE_KEY.startsWith("0x")
? process.env.METAMASK_PRIVATE_KEY : "0x" + process.env.METAMASK_PRIVATE_KEY],
chainId: 11155111,
} },
etherscan: { apiKey: process.env.ETHERSCAN_API_KEY }, // single string, NOT { sepolia: ... }
sourcify: { enabled: false }, // silences the v2.x prompt
};
- Deploy: `npx hardhat run scripts/deploy.cjs --network sepolia`.
- Verify (run RIGHT AFTER deploy, no constructor args for these contracts):
`npx hardhat verify --network sepolia <address>`
On success Etherscan returns "Successfully verified contract … on the block explorer"
and the source becomes readable at
`https://sepolia.etherscan.io/address/<address>#code`.
- Write the deployed address to `src/data/contract.json` so the UI links to
`https://sepolia.etherscan.io/address/<address>`.
CONTRACT (contracts/VisualRoyaltiesManager.sol):
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;
/// @title VisualRoyaltiesManager
/// @notice Automate royalty payments to artists via smart contracts every time artwork changes hands.
/// @notice Built during the Creative AI & Quantum Hackathon organised by StreetKode Fam during Indian Krump Festival 14
contract VisualRoyaltiesManager {
event Logged(address indexed author, string cid, uint256 at);
/// @notice Built during the Creative AI & Quantum Hackathon organised by StreetKode Fam during Indian Krump Festival 14
function log(string calldata cid) external {
emit Logged(msg.sender, cid, block.timestamp);
}
}
```
USER FLOW
1. Land on page -> 'Sign in with Google' (Privy) -> embedded wallet auto-provisioned.
2. User performs a artist royalty automation action; the app calls `log(payload)` on the contract via Privy sponsored tx and shows the Etherscan link as proof.
3. Footer renders: "Built during the Creative AI & Quantum Hackathon organised by StreetKode Fam during Indian Krump Festival 14"
REQUIRED SECRETS (Lovable -> Project Settings -> Secrets):
- METAMASK_PRIVATE_KEY Sepolia deployer key. Fund it: https://cloud.google.com/application/web3/faucet/ethereum/sepolia
- SEPOLIA_RPC_URL Alchemy Sepolia HTTPS endpoint (https://eth-sepolia.g.alchemy.com/v2/<key>). Create a free app at https://dashboard.alchemy.com/ -> copy the HTTPS URL. Public RPCs throttle/fail under hackathon load — Alchemy is required.
- ETHERSCAN_API_KEY For `npx hardhat verify`. Get: https://etherscan.io/myapikey
- PRIVY_APP_ID Google sign-in + sponsored tx. Docs: https://docs.privy.io/llms-full.txt
- PINATA_JWT IPFS uploads (only if app pins media). Docs: https://docs.pinata.cloud/llms-full.txt
CREDIT (must appear in UI footer AND as NatSpec on every deployed contract):
Built during the Creative AI & Quantum Hackathon organised by StreetKode Fam during Indian Krump Festival 14
Market sizing.
TAM
$1.5B
global art royalty market
SAM
$400M
digital art sales platforms
SOM
$50M
blockchain royalty users
Indicative figures for hackathon pitches — refine with your own research before raising.
Adjacent entries.
art ownership tracking
Provenance Palette
Securely track and prove the ownership lineage of paintings with tamper-proof blockchain records.
generative art mintingGenerative Mint Studio
Artists can mint unique generative art pieces directly onto Ethereum Sepolia with automated smart contracts.
gallery exhibition trackingExhibit Chain Ledger
Record every artwork's exhibition history securely and transparently onchain for galleries and collectors.
color authenticity validationColorCode Certifier
Certify and verify exact color compositions of artworks using blockchain color code hashes.