TX-Fuzz is a package containing helpful functions to create random transactions. It can be used to easily access fuzzed transactions from within other programs.

cd cmd/livefuzzer
go build

Run an execution layer client such as Geth locally in a standalone bash window. Tx-fuzz sends transactions to port 8545 by default.

geth --http --http.port 8545

Run livefuzzer.

./livefuzzer spam

spam rotates over every transaction type that shares the plain transaction pool: legacy (0x00), access list (0x01), dynamic fee (0x02) and set code (0x04), as contract creations and as calls, with and without a node-built access list.

Blob transactions (0x03) have a command of their own, blobs, because a node keeps them in a separate pool and refuses to hold both a blob and a non-blob transaction for the same account. Sidecars carry EIP-7594 cell proofs by default; use --blob-sidecar-version 0 to target a node from before Osaka.

pectra spams set code transactions specifically, with authorization lists that mix universal (chain id 0) authorizations, wrong chains and nonces, self-delegation and delegation clearing.

You can optionally specify a seed parameter or a secret key to use as a faucet

./livefuzzer spam --seed <seed> --sk <SK>

You can set the RPC to use with --rpc <RPC>.

spam and blobs reproduce their transactions from the seed, so a run can be replayed. Two things are outside the seed's control: what the node contributes (nonces, gas price and the access lists it builds), and, in pectra or with --corpus, the choice of authorizing account and of corpus element, which still come from global randomness (see FIXES.md).