Chain and Spec

Select which MegaETH spec version and chain ID to use.

These options control which MegaETH spec and chain ID the EVM uses during execution. They are available in the run and tx commands. The replay command auto-detects the spec from the chain ID and block timestamp (see replay).

Options

Flag	Default	Aliases	Description
--spec <SPEC>	Rex7	—	MegaETH spec to use
--chain-id <ID>	6342	--chainid	Chain ID

Available Specs

Spec names are case-sensitive.

Name	Description
Equivalence	Optimism Isthmus compatibility mode
MiniRex	Initial MegaETH execution model with multidimensional gas
Rex	Revised storage gas economics and gas forwarding
Rex1	Compute gas limit reset fix
Rex2	SELFDESTRUCT restored (EIP-6780), KeylessDeploy system contract
Rex3	SLOAD-based oracle detention, increased oracle gas limit
Rex4	Per-call-frame resource budgets, relative gas detention, storage gas stipend
Rex5	SequencerRegistry, dynamic system address (Oracle v2.0.0), storage-gas-stipend separated allowance, resource-accounting fixes
Rex6	Unified gas-metering order, consolidated EIP-7702 accounting, system-tx metering exemption
Rex7	No behavioral change over Rex6 yet (unstable)

Examples

# Use MiniRex spec
mega-evme run 0x600160005260... --spec MiniRex

# Use Equivalence mode (Optimism Isthmus compatible)
mega-evme tx --spec Equivalence --receiver 0x1234...

# Custom chain ID
mega-evme run 0x600160005260... --chain-id 1