Tokenized equities & RWA data layer

import type { TaskContext, Chain } from "compose";

// Dividends must go out on the SAME network the stock token lives on - the
// chain this guide indexes holders from. Robinhood Chain (an Arbitrum Orbit L2)
// isn't a built-in Edge RPC chain yet, so define it as a custom chain and fill
// in its id/RPC. Swap for evm.chains.<name> once it's available on Edge.
const STOCK_CHAIN: Chain = {
  id: 0, // Robinhood Chain testnet chain ID
  name: "Robinhood Chain Testnet",
  testnet: true,
  nativeCurrency: { name: "Ether", symbol: "ETH", decimals: 18 },
  rpcUrls: {
    default: { http: ["https://<robinhood-chain-rpc>"] },
    public: { http: ["https://<robinhood-chain-rpc>"] },
  },
  blockExplorers: { default: { name: "Explorer", url: "https://<explorer>" } },
};

export async function main(
  context: TaskContext,
  payload: { token: string; dividendPerToken: string; recordBlock: number },
) {
  const { fetch, evm } = context;

  // Holders as of the record-date block, from your registry service
  const holders = await fetch<{ address: string; balance: string }[]>(
    `https://registry.example.com/holders?token=${payload.token}&block=${payload.recordBlock}`,
  );

  const wallet = await evm.wallet({ name: "dividend-payer", sponsorGas: true });

  const results = await Promise.allSettled(
    holders.map((h) => {
      const amount = (BigInt(h.balance) * BigInt(payload.dividendPerToken)) / 10n ** 18n;
      // Robinhood Chain stablecoins are ERC-20 - pay with the standard transfer.
      return wallet.writeContract(
        STOCK_CHAIN,
        "0xDIVIDEND_STABLECOIN",
        "transfer(address,uint256)",
        [h.address, amount],
      );
    }),
  );

  const paid = results.filter((r) => r.status === "fulfilled").length;
  return { holders: holders.length, paid };
}