# @solana/kit (/integrations/solana-kit)



`@solana/kit` is the next-gen modular Solana SDK. butr owns the wallet; kit
owns the functional message builder; the wallet's Wallet Standard features own
signing.

## Get the signer and read state [#get-the-signer-and-read-state]

```ts
import { address, createSolanaRpc, type Address } from "@solana/kit";

const rpc = createSolanaRpc("https://api.devnet.solana.com");
const walletStd = (await wallet.connector.getSigner()) as WalletStandardWallet;

const addr: Address = address(wallet.account.walletAddress);
const { value } = await rpc.getBalance(addr).send();
const sol = `${Number(value) / 1_000_000_000} SOL`;
```

## Build and send a transaction [#build-and-send-a-transaction]

Build the message with kit's `pipe()`, compile to a wire transaction, and hand
the bytes to `solana:signAndSendTransaction`:

```ts
import {
  appendTransactionMessageInstruction,
  compileTransaction,
  createTransactionMessage,
  getBase64EncodedWireTransaction,
  pipe,
  setTransactionMessageFeePayer,
  setTransactionMessageLifetimeUsingBlockhash,
} from "@solana/kit";

const { value: latestBlockhash } = await rpc.getLatestBlockhash().send();

const message = pipe(
  createTransactionMessage({ version: 0 }),
  (m) => setTransactionMessageFeePayer(addr, m),
  (m) => setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, m),
  (m) => appendTransactionMessageInstruction(transferIx, m),
);

const compiled = compileTransaction(message);
const wire = getBase64EncodedWireTransaction(compiled);
const bytes = base64ToBytes(wire);

const feature = walletStd.features["solana:signAndSendTransaction"];
if (!feature) throw new Error("Wallet does not advertise solana:signAndSendTransaction");
const account = walletStd.accounts[0];
const [output] = await feature.signAndSendTransaction({
  account,
  chain: "solana:devnet",
  transaction: bytes,
});
```

Message signing uses `solana:signMessage` exactly as in the
[`@solana/web3.js` integration](/integrations/solana-web3js).

<Callout type="info">
  The demo hand-rolls the System Program transfer instruction (a 12-byte buffer: `u32` variant `2` +
  `u64` lamports) rather than depending on `@solana-program/system`, whose codec imports drift
  between `@solana/kit` versions. Either approach works.
</Callout>

<Callout type="info">
  **Source:** `apps/demo-with-solana-kit/src/app.tsx` in the [butr
  repository](https://github.com/pedroapfilho/usebutr/tree/main/apps/demo-with-solana-kit). Targets
  Solana devnet. Run `pnpm dev --filter=demo-with-solana-kit` → `http://localhost:5179`.
</Callout>