🎮 Game Design & Interactive Media · motion capture performance

Algorithmic Choreography Stage

Dancers wear mocap suits to generate interactive lighting rigs powered by the real-time trading volume of WETH.

Privy social + sponsored tx· wallet UX
Section · Onchain

The primitive.

full primer →

Game designers sign in with Google through Privy — no seed phrase, no MetaMask popup — and their motion capture performance actions are sent as sponsored transactions on Robinhood Chain so they never see gas.

Why this primitivePrivy embedded wallets allow live audiences to gaslessly vote on lighting cues using Robinhood Chain's native liquidity.

Kernel
Privy embedded wallet bootstrapped with PRIVY_APP_ID — Google sign-in plus sponsored transactions on Robinhood Chain Testnet so users never see gas
Drives the UI as
a one-click 'Sign in with Google' that drops the user straight into the app with an onchain identity
Appendix · Secrets

Required keys.

METAMASK_PRIVATE_KEY
Exported from MetaMask. Fund on Robinhood Chain Testnet via the faucet.
open ↗
ROBINHOOD_TESTNET_RPC_URL
Alchemy Robinhood Chain Testnet HTTPS endpoint. Create a free app → copy the HTTPS URL.
open ↗
PRIVY_APP_ID
Enables Google sign-in and sponsored tx. Add Robinhood Chain Testnet as a custom EVM chain in the Privy dashboard.
open ↗
PINATA_JWT
Pins images / JSON / manifests to IPFS.
open ↗

Add these in your Lovable project under Settings → Secrets before pasting the prompt below. Blockscout verification needs no API key.

Appendix · Mega-prompt

The build prompt.

Paste into a fresh Lovable project. Make sure all five secrets above are set first. read the build strategy →

Build "Algorithmic Choreography Stage" in ONE Lovable message. Single-page demo.

CONCEPT
Dancers wear mocap suits to generate interactive lighting rigs powered by the real-time trading volume of WETH.
Discipline: Game Design & Interactive Media (motion capture performance).
Onchain primitive: Privy social + sponsored tx. Why this primitive: Privy embedded wallets allow live audiences to gaslessly vote on lighting cues using Robinhood Chain's native liquidity.

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 Robinhood Chain Testnet, verified on Blockscout.
- 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 wraps `<App />` in src/main.tsx. Define the Robinhood Chain Testnet
  as a custom viem chain (viem/chains does not ship it yet):
    import { defineChain } from 'viem';
    export const robinhoodTestnet = defineChain({
      id: 46630,
      name: 'Robinhood Chain Testnet',
      nativeCurrency: { name: 'Ether', symbol: 'ETH', decimals: 18 },
      rpcUrls: { default: { http: [import.meta.env.VITE_ROBINHOOD_TESTNET_RPC_URL || 'https://rpc.testnet.chain.robinhood.com'] } },
      blockExplorers: { default: { name: 'Blockscout', url: 'https://explorer.testnet.chain.robinhood.com' } },
      testnet: true,
    });
    <PrivyProvider appId={import.meta.env.VITE_PRIVY_APP_ID}
      config={{ loginMethods:['google'],
                embeddedWallets:{ ethereum: { createOnLogin:'users-without-wallets' } },
                defaultChain: robinhoodTestnet,
                supportedChains: [robinhoodTestnet] }}>
- All txs via Privy `useSendTransaction` with `{ sponsor: true }` (zero-gas for the user)
  and `{ chainId: 46630 }`.
- Hardhat in /contracts (kept outside the Vite bundle). Install
  `@nomicfoundation/hardhat-toolbox` AND `@nomicfoundation/hardhat-verify@latest`
  (>=3.x — required for Blockscout via customChains).
- hardhat.config.cjs — Blockscout has no API key, so pass a placeholder string:
    require("@nomicfoundation/hardhat-toolbox");
    require("@nomicfoundation/hardhat-verify");
    module.exports = {
      solidity: { version: "0.8.24", settings: { optimizer: { enabled: true, runs: 200 } } },
      networks: { robinhoodTestnet: {
        url: process.env.ROBINHOOD_TESTNET_RPC_URL || "https://rpc.testnet.chain.robinhood.com",
        accounts: [process.env.METAMASK_PRIVATE_KEY.startsWith("0x")
          ? process.env.METAMASK_PRIVATE_KEY : "0x" + process.env.METAMASK_PRIVATE_KEY],
        chainId: 46630,
      } },
      etherscan: {
        apiKey: { robinhoodTestnet: "blockscout-no-key-required" },
        customChains: [{
          network: "robinhoodTestnet",
          chainId: 46630,
          urls: { apiURL: "https://explorer.testnet.chain.robinhood.com/api", browserURL: "https://explorer.testnet.chain.robinhood.com" },
        }],
      },
      sourcify: { enabled: false },
    };
- Deploy: `npx hardhat run scripts/deploy.cjs --network robinhoodTestnet`.
- Verify (run RIGHT AFTER deploy, no constructor args for these contracts):
  `npx hardhat verify --network robinhoodTestnet <address>`
  On success Blockscout marks the contract as verified and the source becomes readable at
  `https://explorer.testnet.chain.robinhood.com/address/<address>#code`.
- Frontend reads: create a viem public client with the Alchemy URL too —
  `createPublicClient({ chain: robinhoodTestnet, transport: http(import.meta.env.VITE_ROBINHOOD_TESTNET_RPC_URL) })`.
  Expose ROBINHOOD_TESTNET_RPC_URL to the client by also setting VITE_ROBINHOOD_TESTNET_RPC_URL
  to the same value.
- Write the deployed address to `src/data/contract.json` so the UI links to
  `https://explorer.testnet.chain.robinhood.com/address/<address>`.

CONTRACT (contracts/AlgorithmicChoreographyStage.sol):
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.24;
/// @title SocialLogAlgorithmicChoreographyStag
/// @notice Dancers wear mocap suits to generate interactive lighting rigs powered by the real-time trading volume of WETH.
/// @notice Built during the Creative AI & Quantum Hackathon organised by StreetKode Fam during Indian Krump Festival 14
contract SocialLogAlgorithmicChoreographyStag {
    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 Robinhood Chain Testnet.
2. Every motion capture performance action the user performs is sent as a sponsored Robinhood Chain tx (`log(payload)`) and displayed with a Blockscout link. No wallet popups.
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         Deployer key. Fund it with testnet ETH from https://faucet.testnet.chain.robinhood.com
- ROBINHOOD_TESTNET_RPC_URL    Alchemy Robinhood Chain Testnet HTTPS endpoint
                               (https://robinhood-testnet.g.alchemy.com/v2/<ALCHEMY_KEY>). Create a free app at
                               https://dashboard.alchemy.com/ (search 'Robinhood Chain' when
                               adding a network) -> copy the HTTPS URL. Public RPC
                               (https://rpc.testnet.chain.robinhood.com) works as a fallback but throttles under load.
- PRIVY_APP_ID                 Google sign-in + sponsored tx. Docs: https://docs.privy.io/llms-full.txt
                               In the Privy dashboard, add a Custom EVM chain: id=46630,
                               name='Robinhood Chain Testnet', rpc=$ROBINHOOD_TESTNET_RPC_URL,
                               explorer=https://explorer.testnet.chain.robinhood.com.
- PINATA_JWT                   IPFS uploads (only if the app pins media). Docs: https://docs.pinata.cloud/llms-full.txt

NOTE: NO ETHERSCAN_API_KEY. Robinhood Chain uses Blockscout, which verifies contracts without an API key.

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
Appendix · Market

Market sizing.

TAM
$12B
global live event and stage tech
SAM
$1B
interactive dance and performance art
SOM
$3M
digital media university programs

Indicative figures for hackathon pitches — refine with your own research before raising.

See also

Adjacent entries.