@solana/kit, Codama & gill (JS/TS)

The modern Solana TypeScript client stack centers on @solana/kit 7.0.0 for RPC, codecs, and transaction messages. Codama generates kit-native clients from Anchor 0.32.1 IDLs. gill is a convenience layer bundling common kit patterns for application code. Together they replace greenfield @solana/web3.js v1 usage on Agave 4.1.1.

Recipe

Quick-reference recipe card - copy-paste ready.

npm install @solana/kit@7.0.0 gill
npm install -D @codama/nodes-from-anchor @codama/renderers-js

import { createSolanaRpc, address, lamports } from "@solana/kit";
 
const rpc = createSolanaRpc("https://api.devnet.solana.com");
const balance = await rpc.getBalance(address("11111111111111111111111111111111")).send();
console.log(balance.value);

When to reach for this:

• New Next.js or React dApps targeting Agave 4.x RPC.
• Generating typed clients after anchor build IDL output.
• Tree-shakable functional imports instead of monolithic web3.js classes.
• Shared codecs between frontend and API routes.

Working Example

import {
  createSolanaRpc,
  createTransactionMessage,
  setTransactionMessageFeePayerSigner,
  setTransactionMessageLifetimeUsingBlockhash,
  appendTransactionMessageInstruction,
  signTransactionMessageWithSigners,
  getSignatureFromTransaction,
  address,
} from "@solana/kit";
import { getTransferSolInstruction } from "@solana-program/system";
import { createKeyPairSignerFromBytes } from "@solana/signers";
import fs from "node:fs";
 
const rpc = createSolanaRpc("https://api.devnet.solana.com");
const secret = Uint8Array.from(JSON.parse(fs.readFileSync(process.env.KEYPAIR!, "utf8")));
const payer = await createKeyPairSignerFromBytes(secret);
 
const { value: latestBlockhash } = await rpc.getLatestBlockhash().send();
 
let message = createTransactionMessage({ version: 0 });
message = setTransactionMessageFeePayerSigner(payer, message);
message = setTransactionMessageLifetimeUsingBlockhash(latestBlockhash, message);
message = appendTransactionMessageInstruction(
  getTransferSolInstruction({
    source: payer,
    destination: address("11111111111111111111111111111111"),
    amount: 1_000n,
  }),
  message,
);
 
const signed = await signTransactionMessageWithSigners(message);
const sig = getSignatureFromTransaction(signed);
await rpc.sendTransaction(signed, { encoding: "base64" }).send();
console.log(sig);

What this demonstrates:

• Functional pipeline composes transaction messages immutably.
• Signers are explicit key pair adapters.
• System program helpers come from @solana-program/* packages.
• RPC uses .send() for typed responses.

Deep Dive

How It Works

• kit splits subpath exports (@solana/rpc, @solana/transaction-messages, codecs).
• Codama reads IDL, builds a node graph, renders TypeScript client functions.
• gill re-exports kit + common program clients for faster app bootstrap.
• Wallet adapters integrate at signer layer - kit stays wallet-agnostic.

TypeScript / NPM Table

Rust Crate Table (parity)

TypeScript Notes

// Regenerate clients when IDL changes
// npx codama run --config codama.json
 
// Prefer bigint lamports in kit examples
const amount = 1_000_000n;

Gotchas

• Mixing web3.js v1 and kit types - duplicate Pubkey models. Fix: migrate modules wholesale per route.
• Stale Codama output after IDL change - runtime encode errors. Fix: CI fails if generated folder dirty.
• Missing signer on message - simulation fails. Fix: setTransactionMessageFeePayerSigner + required signers.
• Assuming gill replaces kit - gill is sugar; understand kit for edge cases. Fix: read underlying kit APIs.
• Wrong RPC feature support - DAS and priority fee APIs vary by provider. Fix: capability matrix per vendor.

Alternatives

FAQs

Related

• @solana/kit Basics - kit primer
• Codama - codegen pipeline
• gill - gill helpers
• Generating TS Clients - workflow

Stack versions: This page was written for Agave 4.1.1, Solana CLI 3.0.10, Anchor 0.32.1, anchor-lang 0.32.1, Rust 1.91.1, @solana/kit 7.0.0, Surfpool 0.12.0, and LiteSVM 0.6.x.