VirtualRunway DAO
Host decentralized, verifiable virtual fashion events with transparent gatekeeping.
Sepolia smart contract· onchain logic
Section · Onchain
full primer →The primitive.
Digital fashion shows gets a tiny Solidity contract deployed to Ethereum Sepolia; fashion designers see a 'verified onchain' badge with the live contract address and a one-tap Etherscan link.
Why this primitiveSmart contracts control access, voting, and payment distribution securely.
Kernel
a Solidity contract deployed to Base Sepolia via MetaMask private key, then verified on BaseScan (Etherscan v2)
Drives the UI as
a 'verified onchain' badge with the live contract address and a BaseScan 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 "VirtualRunway DAO" in ONE Lovable message. Single-page demo.
CONCEPT
Host decentralized, verifiable virtual fashion events with transparent gatekeeping.
Discipline: Fashion & Textile Design (digital fashion shows).
Onchain primitive: Sepolia smart contract. Why this primitive: Smart contracts control access, voting, and payment distribution securely.
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 Base Sepolia (chainId 84532), verified on BaseScan.
- 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).
- Privy embedded wallet — NATIVE Privy gas sponsorship on Base Sepolia (no ZeroDev,
no smart-account SDK, no bundler). The EOA embedded wallet is the tx sender;
Privy's paymaster covers gas so the user sees US$0.00.
- `defaultChain` and `supportedChains` MUST be a REAL viem `defineChain` object,
not a `{ id, name }` stub (a stub compiles but breaks embedded-wallet transport init):
import { defineChain } from "viem";
const baseSepolia = defineChain({
id: 84532, name: "Base Sepolia",
nativeCurrency: { name: "Ether", symbol: "ETH", decimals: 18 },
rpcUrls: { default: { http: [import.meta.env.VITE_BASE_SEPOLIA_RPC_URL || "https://sepolia.base.org"] } },
blockExplorers: { default: { name: "BaseScan", url: "https://sepolia.basescan.org" } },
});
<PrivyProvider appId={import.meta.env.VITE_PRIVY_APP_ID}
config={{ loginMethods:['google'],
embeddedWallets:{ ethereum:{ createOnLogin:'users-without-wallets' } },
defaultChain: baseSepolia as never,
supportedChains: [baseSepolia] as never }}>
- IMPORTANT — Privy mount must be LAZY + CLIENT-ONLY (`@privy-io/react-auth` crashes
under SSR): load `PrivyProvider` via `lazy(() => import('./privy-client-entry'))`
inside `<ClientOnly><Suspense>` in a `privy-root.tsx`. Never import
`@privy-io/react-auth` at module scope of a route file.
- EVERY tx call passes `{ sponsor: true }` AND `address: embedded.address`:
import { useSendTransaction, useWallets } from "@privy-io/react-auth";
const { sendTransaction } = useSendTransaction();
const embedded = wallets.find(w => w.walletClientType === "privy");
const receipt = await sendTransaction(
{ to: CONTRACT_ADDRESS, data, chainId: 84532 },
{ address: embedded.address, sponsor: true },
);
Without `sponsor: true` Privy silently falls back to user-paid gas.
Without `address` Privy may route through a non-embedded wallet and prompt.
- Wrap the `sendTransaction` call in a 45s `Promise.race` timeout whose rejection
message names the two required Privy dashboard settings (below), so the failure
mode is diagnosable from the UI.
- PRIVY DASHBOARD (required, one-time, in the Privy console for VITE_PRIVY_APP_ID):
1. Chains -> add Base Sepolia (84532) AND toggle
"Allow transactions from the client" ON. Without this, `sendTransaction`
hangs forever with no error.
2. Gas Sponsorship -> add a Base Sepolia policy (unlimited or capped).
Without it, embedded wallets need native ETH for gas and hit
"insufficient funds" before the tx ever lands.
- Hardhat in /contracts (kept outside the Vite bundle). Install
`@nomicfoundation/hardhat-ethers` AND `@nomicfoundation/hardhat-verify` (>=2.x).
DO NOT install `@nomicfoundation/hardhat-toolbox` — it drags Hardhat 3 peers.
- hardhat.config.cjs — Base Sepolia + Etherscan v2 single-key:
require("@nomicfoundation/hardhat-ethers");
require("@nomicfoundation/hardhat-verify");
const pk = process.env.METAMASK_PRIVATE_KEY;
module.exports = {
solidity: { version: "0.8.24", settings: { optimizer: { enabled: true, runs: 200 } } },
networks: { baseSepolia: {
url: process.env.BASE_SEPOLIA_RPC_URL || "https://sepolia.base.org",
accounts: pk ? [pk.startsWith("0x") ? pk : "0x" + pk] : [],
chainId: 84532,
} },
etherscan: {
apiKey: process.env.ETHERSCAN_API_KEY, // single Etherscan v2 key covers BaseScan
customChains: [{
network: "baseSepolia", chainId: 84532,
urls: {
apiURL: "https://api.etherscan.io/v2/api?chainid=84532",
browserURL: "https://sepolia.basescan.org",
},
}],
},
sourcify: { enabled: false },
};
- Deploy: `npx hardhat run scripts/deploy.cjs --network baseSepolia`.
- Verify (run RIGHT AFTER deploy, no constructor args for these contracts):
`npx hardhat verify --network baseSepolia <address>`
On success it prints "Successfully verified contract … on the block explorer"
and the source becomes readable at
`https://sepolia.basescan.org/address/<address>#code`.
- Frontend reads: create a viem public client with the Base Sepolia RPC too —
`createPublicClient({ chain: baseSepolia, transport: http(import.meta.env.VITE_BASE_SEPOLIA_RPC_URL) })`
(import `baseSepolia` from `viem/chains`).
Expose the RPC to the client by also setting VITE_BASE_SEPOLIA_RPC_URL to the same value.
- Write the deployed address to `src/data/contract.json` so the UI links to
`https://sepolia.basescan.org/address/<address>`.
CONTRACT (contracts/VirtualRunwayDAO.sol):
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;
/// @title VirtualRunwayDAO
/// @notice Host decentralized, verifiable virtual fashion events with transparent gatekeeping.
/// @notice Built during the Creative AI & Quantum Hackathon organised by StreetKode Fam during Indian Krump Festival 14
contract VirtualRunwayDAO {
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 on Base Sepolia.
2. User performs a digital fashion shows action; the app calls `log(payload)` on the contract via Privy sponsored tx and shows the BaseScan 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 Base Sepolia deployer key. Fund it: https://portal.cdp.coinbase.com/products/faucet
(alt: https://www.alchemy.com/faucets/base-sepolia)
- BASE_SEPOLIA_RPC_URL Alchemy Base Sepolia HTTPS endpoint (https://eth-base-sepolia.g.alchemy.com/v2/<key>)
OR the public default https://sepolia.base.org. Create a free app: https://dashboard.alchemy.com/
- ETHERSCAN_API_KEY Single Etherscan v2 key — verifies on BaseScan (chainId 84532) with no extra key.
Get: https://etherscan.io/myapikey
- PRIVY_APP_ID Google sign-in + sponsored tx. Enable Base Sepolia (84532) in your Privy dashboard.
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
$1.2B
fashion design software market
SAM
$90M
virtual event platforms
SOM
$7M
designers producing blockchain-secured shows
Indicative figures for hackathon pitches — refine with your own research before raising.
Adjacent entries.
material provenance
FabricTrace Ledger
Track and verify organic fabric sources to assure sustainable fashion claims.
design copyrightDesignAuth Mint
Securely register and timestamp original fashion designs to prevent copying.
color curationColorPalette DAO
Collaboratively create and share color palettes with verified ownership and royalty rules.
virtual try-onVirtualFitting NFT
Create unique virtual fitting sessions minted as NFTs for secure client access.