Sponsor gas with Pimlico on Celo

npm install permissionless viem

https://api.pimlico.io/v2/42220/rpc?apikey=YOUR_API_KEY      # Celo mainnet
https://api.pimlico.io/v2/11142220/rpc?apikey=YOUR_API_KEY   # Celo Sepolia

// Celo Sepolia (11142220). For mainnet use `celo` from viem/chains and 42220 in the Pimlico URL.
import { createPublicClient, http } from "viem";
import { privateKeyToAccount } from "viem/accounts";
import { celoSepolia } from "viem/chains";
import { entryPoint07Address } from "viem/account-abstraction";
import { createSmartAccountClient } from "permissionless";
import { toSimpleSmartAccount } from "permissionless/accounts";
import { createPimlicoClient } from "permissionless/clients/pimlico";

const pimlicoUrl = `https://api.pimlico.io/v2/11142220/rpc?apikey=${process.env.PIMLICO_API_KEY}`;

const publicClient = createPublicClient({
  chain: celoSepolia,
  transport: http("https://forno.celo-sepolia.celo-testnet.org"),
});

const pimlicoClient = createPimlicoClient({
  transport: http(pimlicoUrl),
  entryPoint: { address: entryPoint07Address, version: "0.7" },
});

const account = await toSimpleSmartAccount({
  client: publicClient,
  owner: privateKeyToAccount(process.env.OWNER_PRIVATE_KEY as `0x${string}`),
  entryPoint: { address: entryPoint07Address, version: "0.7" },
});
console.log("smart account:", account.address);

const smartAccountClient = createSmartAccountClient({
  account,
  chain: celoSepolia,
  bundlerTransport: http(pimlicoUrl),
  paymaster: pimlicoClient,
  userOperation: {
    estimateFeesPerGas: async () => (await pimlicoClient.getUserOperationGasPrice()).fast,
  },
});

const txHash = await smartAccountClient.sendTransaction({
  to: "0x0000000000000000000000000000000000000000", // example: replace with your contract
  value: 0n,
  data: "0x",
});
console.log("transaction:", `https://celo-sepolia.blockscout.com/tx/${txHash}`);