# Can builders unbundle and include extra transactions in searcher's bundle?
**URL:** https://collective.flashbots.net/t/can-builders-unbundle-and-include-extra-transactions-in-searchers-bundle/1659
**Category:** Block Builders
**Tags:** question
**Created:** [April 21, 2023, 5:29pm UTC](https://collective.flashbots.net/t/can-builders-unbundle-and-include-extra-transactions-in-searchers-bundle/1659 "2023-04-21T17:29:09Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@zzh1](https://collective.flashbots.net/u/zzh1)
#### Post date: [April 21, 2023, 5:29pm UTC](https://collective.flashbots.net/t/can-builders-unbundle-and-include-extra-transactions-in-searchers-bundle/1659/1 "2023-04-21T17:29:09Z")
Suppose I am a searcher who sends a bundle to a builder for arbitrage that requires sequential execution. Can the builder insert additional transactions in my bundle to attack me? How is the searcher protected in this scenario?
---
### Author:  [@Fred](https://collective.flashbots.net/u/Fred)
#### Post date: [May 2, 2023, 8:58am UTC](https://collective.flashbots.net/t/can-builders-unbundle-and-include-extra-transactions-in-searchers-bundle/1659/2 "2023-05-02T08:58:11Z")
Block builders today have full control of the content in their blocks and have the ability to remove and/or insert transactions at any position. You can find some more details on how searchers and builders interact, and a some criteria to look for in a block builder, in our [Documentation](https://docs.flashbots.net/flashbots-auction/overview) and in [Searching Post-Merge](https://collective.flashbots.net/t/searching-post-merge/891).
We are working on reducing these trust assumptions, [since March we’ve been running](https://etherscan.io/address/0xc83dad6e38bf7f2d79f2a51dd3c4be3f530965d6) a [block builder inside an SGX enclave](https://writings.flashbots.net/block-building-inside-sgx), bringing us one step closer toward transaction confidentiality and decentralization of the block-building role.
Moving forward, with [SUAVE](https://collective.flashbots.net/tag/suave), we seek to substitute these trust guarantees further with robust cryptographic and cryptoeconomic assurances for comprehensive programmable privacy.
---
### Author:  [@Kosala](https://collective.flashbots.net/u/Kosala)
#### Post date: [April 19, 2024, 3:49pm UTC](https://collective.flashbots.net/t/can-builders-unbundle-and-include-extra-transactions-in-searchers-bundle/1659/3 "2024-04-19T15:49:26Z")
> [@zzh1](#):
>
> se I am a searcher who sends a bundle to a builder for arbitrage that requires sequential execution.
How to send bundles to a block builder? I am running falshbots block builder and need to send bundles to block builder. I used the following code, used BUILDER\_URL, does not work.
const flashbotsProvider = await FlashbotsBundleProvider.create(
RPC\_PROVIDER, // ethers.js provider, to perform gas estimiations and nonce lookups
wallet, // ethers.js signer wallet
BUILDER\_URL,
BLOCKCHAIN\_NAME
);
```
for (var i = 1; i <= 10; i++) {
//bundle submission
const bundleSubmission = await flashbotsProvider.sendRawBundle(
signedTransactions,
blockNumber + i
)
const waitResponse = await bundleSubmission.wait()
//check bundle inclusion
if (
waitResponse === FlashbotsBundleResolution.BundleIncluded ||
waitResponse === FlashbotsBundleResolution.AccountNonceTooHigh
) {
console.log('Bundle included !!!')
process.exit(0)
} else {
console.log("bundle not included !!!" + i)
console.log({
bundleStats: await flashbotsProvider.getBundleStats(
simulation.bundleHash,
blockNumber + 1,
),
userStats: await flashbotsProvider.getUserStats(),
})
}
}
```