You define your maximum slippage tolerance for each trade (eg. 1%)
You broadcast your bundle to one or more block builders.
You wait about 12 seconds (1 block) or more for it to be included.
During this time, you have no guarantee that:
Your entire bundle will be included in the next block.
The transactions won’t revert due to changing conditions.
Other mev actors won’t push your transaction toward your slippage limit
As a result of these factors:
You might miss your target prices.
You might pay gas for failed transactions.
Your bundle may not get included, which is especially problematic for single-shot opportunities in DeFi. Some arbitrage opportunities only exist for a very brief window, and missing this window means losing the entire opportunity.
Instead of blindly sending your transaction, you can use an execution preconf. Here’s how:
1
Setting up your mev-commit bidder node
Follow the Quickstart guide to set up your mev-commit bidder node and fund your account.
2
Prepare your transaction
Identify your mev opportunity. Craft your bundle and send the signed transaction to block builders as per usual.
3
Submit a preconf bid
Create and submit a bid for the transaction from your mev-commit bidder node (following the bid structure here), supplying the hash of the transaction you just sent.
When you submit a bid, it goes to multiple providers by default.
If a provider accepts your bid, it will generate a cryptographic commitment to execute your transaction. These are typically sent in milliseconds.
Your bidder node automatically verifies each commitment it receives.
Aim to receive commitments from all registered providers. If you don’t, consider increasing your bid amount to make it more attractive to all providers.
4
Execution
Your transaction is now guaranteed to be executed as per the preconf terms for that provider (or else that provider will be slashed).
The transaction will execute in the specified block.
Benefits
Real-time confirmation of future execution, translating to reduced risk for transacting
Ability to secure a specific execution slot at a better price
Even in the event of being frontrun, your transaction parameters will remain within your defined slippage, or else not execute
Instant transaction UX for searchers
Predictable gas costs
By using a preconf, you’ve eliminated the uncertainty of the 12-second wait, secured your execution parameters, and protected yourself against potential mev exploitation, all in real-time.Unlike simple inclusion preconfirmations (which might still result in reverted transactions), execution preconfs ensure your bundle executes as intended. This leaderless, multi-provider approach offers superior guarantees that improve your chances to capture time-sensitive mev opportunities.