Jito Bundles

Send flash loans as private, atomic bundles via Jito Block Engine. Your transaction bypasses the public mempool — invisible to MEV bots.

Code Examples

const sig = await flash.executeLocal({
  token: 'SOL',
  amount: 5000,
  onFunds: async (ixs) => {
    ixs.push(myLiquidationIx);
    return ixs;
  },
}, {
  sendVia: 'jito',
  jito: {
    tip: 'competitive',    // auto-calculated tip
    region: 'amsterdam',   // nearest Block Engine
  },
});

Tip Strategies

What Jito Gives You

• ✅ Bundle privacy — your TX is not visible in the public mempool
• ✅ Frontrun protection — MEV bots can't see your transaction before it lands
• ✅ Auto-calculated tip — based on Jito tip floor with your chosen strategy
• ✅ Smart Retry compatible — escalates tip amount on retry failure
• ✅ Zero new dependencies — uses pure fetch() to Block Engine API

Limitations

• ❌ No landing guarantee — tip is competitive, not a hard guarantee of inclusion
• ❌ Not full MEV protection — bundles are private, but not invulnerable to all MEV

Block Engine Regions

pollBundleStatus()

After sending a bundle, poll the Block Engine to verify it landed. The SDK does this automatically with sendVia: 'jito', but you can use it directly:

import { sendJitoBundle, pollBundleStatus, resolveBlockEngineUrl } from '@vaea/flash';

const url = resolveBlockEngineUrl('amsterdam');
const bundleId = await sendJitoBundle(url, [signedTx]);

// Poll every 500ms until confirmed (max 30s)
const signature = await pollBundleStatus(url, bundleId, 30_000);
console.log('Bundle landed:', signature);