The builder is built as an extension to the
reth execution layer (EL) client and also requires a consensus layer (CL) client to run.
The default builder simply uses
reth's local mempool when sourcing transactions.
The best way to run the builder right now is to build this project from source.
Follow the steps here under
You can install the
mev-rs binary, named
mev, with the following steps:
git clone https://github.com/ralexstokes/mev-rs cd mev-rs cargo install --locked
The builder has been verified as of this commit
bf3d41f026e9728233dd3e1c40e75c49b9ae00b3. No guarantees about other states of the repository currently.
cargo install command should place the
mev binary under the default
.cargo/bin folder which is also in your
PATH following the suggested Rust installation process.
Once installed, we are ready to run the builder.
Before we can run the builder, we need to sync a CL and EL node pair on our target network.
The remainder of this document will assume we are building for the
Repository has only been tested on the Sepolia network and there is no guarantee the builder works on other networks.
Repository has only been tested with Lighthouse and there is no guarantee other CLs will work.
Doing the initial/bulk sync from the
mev builder should be possible, but has not been tested.
The recommended approach will be to run
reth (ideally built from source at the same commit pinned in this repo) for the target network alongside the CL until the pair has reached the head of the chain.
Example commands utilizing checkpoint sync following the Lighthouse book to do this:
Make the JWT secret (refer to the Lighthouse guide for more info).
[recommended] Obtain a checkpoint sync URL if you wish to use this sync mode.
reth --chain sepolia \ node \ --http \ --authrpc.jwtsecret $JWT_SECRET_FILE_PATH
lighthouse --network sepolia \ bn \ --http \ --execution-endpoint http://localhost:8551 \ --execution-jwt $JWT_SECRET_FILE_PATH \ --disable-deposit-contract-sync \ --checkpoint-sync-url $CHECKPOINT_SYNC_PROVIDER
The pair should start syncing. Once the pair of nodes is fully synced you can stop
reth and run the
mev builder in its place.
- running the builder without having a synced database already has not been tested
- the builder will wait anyway until the head of the chain has been synced
To run the
mev builder, first you should make the appropriate configuration. You can make a local copy of
example.config.toml to get started.
To configure the builder, you can edit the fields under the
[builder] key of the TOML.
Fields you should change:
execution_mnemonic: update to a seed phrase of an ethereum wallet you control. This wallet will be used to author payment transactions to the proposer and also is used as the source of funds for any subsidy value you wish to add to the block. You can select a particular index (following BIP-39) by terminating the seed phrase with a
:Nand integer index
N. Otherwise the builder will just use the first index from the key tree.
subsidy_gwei: set this value to 0 if your execution layer address has no ETH in it; otherwise, the blocks will be invalid.
jwt_secret_path: ensure this value matches the one used previously when doing the initial sync.
Once the configuration looks good, you can run the builder as follows alongside
lighthousehas some additional configuration from above to ensure the builder always receives head updates from the chain.
mevwith config file
mev --network sepolia build config.toml
lighthouse --network sepolia \ bn \ --http \ --execution-endpoint http://localhost:8551 \ --execution-jwt $JWT_SECRET_FILE_PATH \ --disable-deposit-contract-sync \ --checkpoint-sync-url $CHECKPOINT_SYNC_PROVIDER --always-prepare-payload --suggested-fee-recipient $FEE_RECIPIENT
lighthouseis ultimately not used, but currently required to run the node. Any valid address should do and it should not affect the builder.
- If you are seeing slow or lagging operation, you can try to adjust the preparation lookahead with the
- The builder has been tested on an AWS EC2 instance of
t3.xlargevariety with a
- You can control the logging level of
RUST_LOGenvironment variable. For example, to silence the
rethlogs, you can run
RUST_LOG=mev=info mev --network sepolia build config.toml