Bankrun (TS)

Bankrun provides fast in-process Solana VM tests from TypeScript without running solana-test-validator. Use it when your team lives in Anchor TS tests but needs LiteSVM-like speed.

Recipe

Quick-reference recipe card - copy-paste ready.

import { startAnchor, BankrunProvider } from "anchor-bankrun";
import { Program } from "@coral-xyz/anchor";
 
const context = await startAnchor("", [], []);
const provider = new BankrunProvider(context);
const program = new Program(idl, provider);

When to reach for this:

• Anchor TS tests too slow on validator spin-up.
• Testing multiple instructions in one TypeScript file quickly.
• Teams preferring Mocha/chai over Rust #[test].
• CI pipelines avoiding flaky validator ports.

Working Example

import { startAnchor, BankrunProvider } from "anchor-bankrun";
import { Program, BN } from "@coral-xyz/anchor";
import { Keypair, PublicKey } from "@solana/web3.js";
import { describe, it } from "node:test";
import assert from "node:assert/strict";
 
describe("vault bankrun", async () => {
  const context = await startAnchor(".", [], []);
  const provider = new BankrunProvider(context);
  const program = new Program(idl as any, provider);
 
  it("deposits tokens", async () => {
    const user = Keypair.generate();
    context.setAccount(user.publicKey, {
      lamports: 1_000_000_000,
      data: Buffer.alloc(0),
      owner: PublicKey.default,
      executable: false,
    });
 
    const [vaultPda] = PublicKey.findProgramAddressSync(
      [Buffer.from("vault"), user.publicKey.toBuffer()],
      program.programId
    );
 
    await program.methods
      .deposit(new BN(500_000))
      .accounts({ user: user.publicKey, vault: vaultPda })
      .signers([user])
      .rpc();
 
    const vault = await program.account.vault.fetch(vaultPda);
    assert.equal(vault.balance.toNumber(), 500_000);
  });
});

What this demonstrates:

• startAnchor loads workspace programs into in-process VM.
• BankrunProvider wires Anchor client without localhost RPC.
• context.setAccount seeds account state before instructions.

Deep Dive

How It Works

• Bankrun embeds SVM similar to LiteSVM but exposes Node-friendly API.
• Anchor program IDs and .so artifacts load from workspace paths.
• Transactions submit through provider like normal Anchor tests.
• No port 8899 - eliminates validator race conditions in CI.

Bankrun vs anchor test

TypeScript Notes

// Warp clock for time-dependent ix
context.warpToSlot(100n);

Gotchas

• IDL out of sync - Stale IDL causes account resolution errors. Fix: anchor build before tests.
• Missing SPL programs - Token CPIs need explicit program accounts in workspace config. Fix: Include spl_token.so in startAnchor program list.
• Account rent - Underfunded accounts fail silently. Fix: Set lamports above rent-exempt minimum in setAccount.
• Not mainnet state - No fork by default. Fix: Use Surfpool for DeFi integration layer.
• Version drift - Bankrun must match Solana SDK used by Anchor 0.32.1. Fix: Pin versions in package.json.
• signers in rpc() - Forgetting .signers([user]) on mutating ix. Fix: Mirror validator test patterns.

Alternatives

FAQs

Related

• Anchor TS Tests - validator-based Anchor tests
• LiteSVM - Rust equivalent
• Testing Basics - pyramid
• Testing Best Practices - CI policy

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.