> For the complete documentation index, see [llms.txt](https://docs.blinklabs.xyz/blink/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.blinklabs.xyz/blink/bnb-smart-chain-bsc/how-it-works.md).

# How it works

BNB Smart Chain produces sub-second blocks and, unlike Base or Arbitrum, has both a public mempool and a competitive builder market. Blink routes your transactions privately to that builder market, so they never sit in the public mempool where they can be seen and sandwiched.

When a transaction is sent via Blink, we share it with our trusted searcher network. Searchers may submit backrun transactions to capture arbitrage opportunities. For transactions that successfully land on-chain and are backrun, Blink may return a portion of that value to the transaction originator.

Transactions that revert, fail, or are not included on-chain are not eligible for refunds or value sharing.

### Flow Overview

1. Transaction Submission
   * Users submit through Blink's BSC endpoint, either as single transactions or as atomic bundles
   * Transactions bypass the public mempool and are forwarded directly to BSC builders
2. Searcher Integration
   * Vetted searchers receive transaction details over Blink's WebSocket feed
   * Each broadcast opens a short bidding window for that transaction
   * Transactions with no realistic MEV, such as simple BNB transfers and plain token transfers, are never shared
3. Auction and Submission
   * Searchers submit backrun bundles, which Blink simulates on arrival to determine each bid
   * When the window closes, Blink submits the winning bundle to the builder itself
   * Losing bundles are dropped. They are never forwarded or exposed
4. Profit Distribution
   * The winning searcher pays their bid to Blink inside their own bundle
   * Blink passes a portion of that value back to the originator of the transaction

### Differences with Ethereum

#### 1. Cheaper gas = higher quantity of profitable opportunities

Because it's cheaper to send transactions on BSC, the point at which opportunities become profitable for searchers is lower. This means that much lower value transactions can provide value back.

#### 2. A different builder market

BSC has builders, but not Ethereum's proposer-builder separation via MEV-Boost relays. Blink fans every transaction out to the major BSC builders in parallel rather than relying on a single relay, and for some flow sends to one builder exclusively for a block before fanning out more widely.

#### 3. There is a public mempool

Unlike Base and Arbitrum, BSC runs a public mempool, so sandwiching is a routine risk rather than a theoretical one. Blink never broadcasts your transaction to it — transactions go straight to builders privately.

#### 4. Blink runs the auction and submits the winner

On Base, searchers submit their own backruns and the sequencer orders them first-come-first-served. On BSC, Blink runs a sealed auction: bids are scored by simulation, the winner is submitted to the builder by Blink, and searchers are prohibited from submitting Blink flow themselves. See [Searchers](/blink/bnb-smart-chain-bsc/searchers.md) for the full rules.

#### 5. Bundles are supported

Unlike Base and Arbitrum, BSC has a real concept of bundles. Originators can submit atomic bundles via [`eth_sendBundle`](/blink/bnb-smart-chain-bsc/api-reference.md#eth_sendbundle), and value recovered by a backrun is attributable directly to the bundle it backran, rather than having to be inferred.

### Gas Sponsorship

BSC also supports gas sponsored swaps, letting your users transact without holding any BNB. See [Gas Sponsorship](/blink/bnb-smart-chain-bsc/gas-sponsorship.md) for details.