• 🦄 All hardforks up till Pectra
• 🌴 Tree-shakeable API
• 👷🏼 Controlled dependency set (7 external + @Noble crypto)
• 🧩 Flexible EIP on/off engine
• 🛠️ Custom precompiles
• 🚀 Build-in profiler
• 🪢 User-friendly colored debugging
• 🛵 422KB bundle size (110KB gzipped)
• 🏄🏾‍♂️ WASM-free default + Fully browser ready

• Installation
• Getting Started
• Examples
• Browser
• API
• Architecture
• Supported Hardforks
• Supported EIPs
• Precompiles
• Events
• Understanding the EVM
• Profiling the EVM
• Development
• EthereumJS
• License

To obtain the latest version, simply require the project using npm:

npm install @ethereumjs/evm

This package provides the core Ethereum Virtual Machine (EVM) implementation which is capable of executing EVM-compatible bytecode. The package has been extracted from the @ethereumjs/vm package along the VM v6 release.

Note: Starting with the Dencun hardfork EIP-4844 related functionality has become an integrated part of the EVM functionality with the activation of the point evaluation precompile. For this precompile to work a separate installation of the KZG library is necessary (we decided not to bundle due to large bundle sizes), see KZG Setup for instructions.

The following is the simplest example for an EVM instantiation with reasonable defaults for state and blockchain information (like blockhashes):

// ./examples/simple.ts

import { createEVM } from '@ethereumjs/evm'
import { hexToBytes } from '@ethereumjs/util'

const main = async () => {
  const evm = await createEVM()
  const res = await evm.runCode({ code: hexToBytes('0x6001') }) // PUSH1 01 -- simple bytecode to push 1 onto the stack
  console.log(res.executionGasUsed) // 3n
}

void main()

If the EVM should run on a certain state an @ethereumjs/statemanager is needed. An @ethereumjs/blockchain instance can be passed in to provide access to external interface information like a blockhash:

// ./examples/withBlockchain.ts

import { createBlockchain } from '@ethereumjs/blockchain'
import { Common, Hardfork, Mainnet } from '@ethereumjs/common'
import { createEVM } from '@ethereumjs/evm'
import { MerkleStateManager } from '@ethereumjs/statemanager'
import { bytesToHex, hexToBytes } from '@ethereumjs/util'

import type { PrefixedHexString } from '@ethereumjs/util'

const main = async () => {
  const common = new Common({ chain: Mainnet, hardfork: Hardfork.Shanghai })
  const stateManager = new MerkleStateManager()
  const blockchain = await createBlockchain()

  const evm = await createEVM({
    common,
    stateManager,
    blockchain,
  })

  const STOP = '00'
  const ADD = '01'
  const PUSH1 = '60'

  // Note that numbers added are hex values, so '20' would be '32' as decimal e.g.
  const code = [PUSH1, '03', PUSH1, '05', ADD, STOP]

  evm.events.on('step', function (data) {
    // Note that data.stack is not immutable, i.e. it is a reference to the vm's internal stack object
    console.log(`Opcode: ${data.opcode.name}\tStack: ${data.stack}`)
  })

  const results = await evm.runCode({
    code: hexToBytes(('0x' + code.join('')) as PrefixedHexString),
    gasLimit: BigInt(0xffff),
  })

  console.log(`Returned: ${bytesToHex(results.returnValue)}`)
  console.log(`gasUsed: ${results.executionGasUsed.toString()}`)
}

void main()

Additionally this usage example shows the use of events to listen on the inner workings and procedural updates (step event) of the EVM.

This library by default uses JavaScript implementations for the basic standard crypto primitives like hashing or signature verification (for included txs). See @ethereumjs/common README for instructions on how to replace with e.g. a more performant WASM implementation by using a shared common instance.

See the examples folder for different meaningful examples on how to use the EVM package and invoke certain aspects of it, e.g. running a bytecode snippet, listening to events or activate an EVM with a certain EIP for experimental purposes.

We provide hybrid ESM/CJS builds for all our libraries. With the v10 breaking release round from Spring 2025, all libraries are "pure-JS" by default and we have eliminated all hard-wired WASM code. Additionally we have substantially lowered the bundle sizes, reduced the number of dependencies, and cut out all usages of Node.js-specific primitives (like the Node.js event emitter).

It is easily possible to run a browser build of one of the EthereumJS libraries within a modern browser using the provided ESM build. For a setup example see ./examples/browser.html.

For documentation on EVM instantiation, exposed API and emitted events see generated API docs.

With the breaking releases from Summer 2023 we have started to ship our libraries with both CommonJS (cjs folder) and ESM builds (esm folder), see package.json for the detailed setup.

If you use an ES6-style import in your code files from the ESM build will be used:

import { EthereumJSClass } from '@ethereumjs/[PACKAGE_NAME]'

If you use Node.js specific require, the CJS build will be used:

const { EthereumJSClass } = require('@ethereumjs/[PACKAGE_NAME]')

Using ESM will give you additional advantages over CJS beyond browser usage like static code analysis / Tree Shaking which CJS can not provide.

This package contains the inner Ethereum Virtual Machine core functionality which was included in the @ethereumjs/vm package up till v5 and has been extracted along the v6 release.

This will make it easier to customize the inner EVM, which can now be passed as an optional argument to the outer VM instance.

For the EVM to properly work it needs access to a respective execution environment (to e.g. request on information like block hashes) as well as the connection to an outer account and contract state.

With the v2 release EVM, VM and StateManager have been substantially reworked in this regard, see PR #2649 and PR #2702 for further deepening context.

The interfaces (in a non-TypeScript sense) between these packages have been simplified and the EEI package has been completely removed. Most of the EEI related logic is now either handled internally or more generic functionality being taken over by the @ethereumjs/statemanager package.

This allows for both a standalone EVM instantiation with reasonable defaults as well as for a simplified EVM -> VM passing if a customized EVM is needed.

The EthereumJS EVM implements all hardforks from Frontier (chainstart) up to the latest active mainnet hardfork.

Currently the following hardfork rules are supported:

• chainstart (a.k.a. Frontier)
• homestead
• tangerineWhistle
• spuriousDragon
• byzantium
• constantinople
• petersburg
• istanbul
• muirGlacier (only mainnet)
• berlin (v5.2.0+)
• london (v5.4.0+)
• arrowGlacier (only mainnet) (v5.6.0+)
• merge
• shanghai (v2.0.0+)
• cancun (v2.0.0+)
• prague (v10+)

Default: prague (taken from Common.DEFAULT_HARDFORK)

A specific hardfork EVM ruleset can be activated by passing in the hardfork along the Common instance to the outer @ethereumjs/vm instance.

If you want to activate an EIP not currently active on the hardfork your common instance is set to, it is possible to individually activate EIP support in the EVM by specifying the desired EIPs using the eips property in your CommonOpts setup, e.g.:

// ./examples/eips.ts

import { Common, Hardfork, Mainnet } from '@ethereumjs/common'
import { createEVM } from '@ethereumjs/evm'

const main = async () => {
  const common = new Common({ chain: Mainnet, hardfork: Hardfork.Cancun, eips: [7702] })
  const evm = await createEVM({ common })
  console.log(`EIP 7702 is active in isolation on top of the Cancun HF - ${evm.common.isActivatedEIP(7702)}`)
}

void main()

Currently supported EIPs:

• EIP-1153 - Transient storage opcodes (Cancun)
• EIP-1559 - Fee market change for ETH 1.0 chain
• EIP-2537 - Precompile for BLS12-381 curve operations (Prague)
• EIP-2565 - ModExp gas cost
• EIP-2718 - Transaction Types
• EIP-2935 - Serve historical block hashes in state (Prague)
• EIP-2929 - gas cost increases for state access opcodes
• EIP-2930 - Optional access list tx type
• EIP-3074 - AUTH and AUTHCALL opcodes
• EIP-3198 - Base fee Opcode
• EIP-3529 - Reduction in refunds
• EIP-3541 - Reject new contracts starting with the 0xEF byte
• EIP-3554 - Difficulty Bomb Delay to December 2021 (only PoW networks)
• EIP-3607 - Reject transactions from senders with deployed code
• EIP-3651 - Warm COINBASE (Shanghai)
• EIP-3675 - Upgrade consensus to Proof-of-Stake
• EIP-3855 - Push0 opcode (Shanghai)
• EIP-3860 - Limit and meter initcode (Shanghai)
• EIP-4345 - Difficulty Bomb Delay to June 2022
• EIP-4399 - Supplant DIFFICULTY opcode with PREVRANDAO (Merge)
• EIP-4788 - Beacon block root in the EVM (Cancun)
• EIP-4844 - Shard Blob Transactions (Cancun)
• EIP-4895 - Beacon chain push withdrawals as operations (Shanghai)
• EIP-5133 - Delaying Difficulty Bomb to mid-September 2022 (Gray Glacier)
• EIP-5656 - MCOPY - Memory copying instruction (Cancun)
• EIP-6110 - Supply validator deposits on chain (Prague)
• EIP-6780 - SELFDESTRUCT only in same transaction (Cancun)
• EIP-7002 - Execution layer triggerable exits (Prague)
• EIP-7251 - Increase the MAX_EFFECTIVE_BALANCE (Prague)
• EIP-7516 - BLOBBASEFEE opcode (Cancun)
• EIP-7623 - Increase calldata cost (Prague)
• EIP-7685 - General purpose execution layer requests (Prague)
• EIP-7691 - Blob throughput increase (Prague)
• EIP-7692 - EVM Object Format (EOF) v1 (experimental)
• EIP-7702 - Set EOA account code (Prague)
• EIP-7709 - Read BLOCKHASH from storage and update cost (Verkle)

This library supports the blob transaction type introduced with EIP-4844. EIP-4844 comes with a dedicated opcode BLOBHASH and has added a new point evaluation precompile at address 0x0a.

Note: Usage of the point evaluation precompile needs a manual KZG library installation and global initialization, see KZG Setup for instructions.

This library support all EVM precompiles up to the Prague hardfork.

The following code allows to run precompiles in isolation, e.g. for testing purposes:

// ./examples/precompile.ts

import { Common, Hardfork, Mainnet } from '@ethereumjs/common'
import { createEVM, getActivePrecompiles } from '@ethereumjs/evm'
import { bytesToHex, hexToBytes } from '@ethereumjs/util'

const main = async () => {
  const common = new Common({ chain: Mainnet, hardfork: Hardfork.Prague })

  // Taken from test/eips/precompiles/bls/add_G1_bls.json
  const data = hexToBytes(
    '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',
  )
  const gasLimit = BigInt(5000000)

  const evm = await createEVM({ common })
  const precompile = getActivePrecompiles(common).get('000000000000000000000000000000000000000b')!

  const callData = {
    data,
    gasLimit,
    common,
    _EVM: evm,
  }
  const result = await precompile(callData)
  console.log(`Precompile result:${bytesToHex(result.returnValue)}`)
}

void main()

Starting with v10 the EVM supports the BLS precompiles introduced with EIP-2537 in its final version introduced with the Prague hardfork. These precompiles run natively using the @noble/curves library (❤️ to @paulmillr!).

An alternative WASM implementation (using bls-wasm) can be optionally used like this if needed for performance reasons:

import { EVM, MCLBLS } from '@ethereumjs/evm'

const common = new Common({ chain: Chain.Mainnet, hardfork: Hardfork.Prague })
await mcl.init(mcl.BLS12_381)
const mclbls = new MCLBLS(mcl)
const evm = await createEVM({ common, bls })

The EVM emits events that support async listeners (using EventEmitter3).

You can subscribe to the following events:

• beforeMessage: Emits a Message right after running it.
• afterMessage: Emits an EVMResult right after running a message.
• step: Emits an InterpreterStep right before running an EVM step.
• newContract: Emits a NewContractEvent right before creating a contract. This event contains the deployment code, not the deployed code, as the creation message may not return such a code.

You can perform asynchronous operations from within an event handler and prevent the EVM to keep running until they finish.

If subscribing to events with an async listener, specify the second parameter of your listener as a resolve function that must be called once your listener code has finished.

See below for example usage:

// ./examples/eventListener.ts#L7-L14

evm.events.on('beforeMessage', (event) => {
  console.log('synchronous listener to beforeMessage', event)
})
evm.events.on('afterMessage', (event, resolve) => {
  console.log('asynchronous listener to beforeMessage', event)
  // we need to call resolve() to avoid the event listener hanging
  resolve?.()
})

If an exception is passed to that function, or thrown from within the handler or a function called by it, the exception will bubble into the EVM and interrupt it, possibly corrupting its state. It's strongly recommended not to do that.

If you want to understand your EVM runs we have added a hierarchically structured list of debug loggers for your convenience which can be activated in arbitrary combinations. We also use these loggers internally for development and testing. These loggers use the debug library and can be activated on the CL with DEBUG=ethjs,[Logger Selection] node [Your Script to Run].js and produce output like the following:

The following loggers are currently available:

Here are some examples for useful logger combinations.

Run one specific logger:

DEBUG=ethjs,evm tsx test.ts

Run all loggers currently available:

DEBUG=ethjs,evm:*,evm:*:* tsx test.ts

Run only the gas loggers:

DEBUG=ethjs,evm:*:gas tsx test.ts

Excluding the ops logger:

DEBUG=ethjs,evm:*,evm:*:*,-evm:ops tsx test.ts

Run some specific loggers including a logger specifically logging the SSTORE executions from the EVM (this is from the screenshot above):

DEBUG=ethjs,evm,evm:ops:sstore,evm:*:gas tsx test.ts

ethjs must be included in the DEBUG environment variables to enable any logs. Additional log selections can be added with a comma separated list (no spaces). Logs with extensions can be enabled with a colon :, and * can be used to include all extensions.

DEBUG=ethjs,evm:journal,evm:ops:* npx vitest test/runCall.spec.ts

The EVM processes state changes through a hierarchical flow of execution:

The runCall method handles the execution of messages, which can be either contract calls or contract creations:

• Creates a checkpoint in the state
• Sets up the execution environment (block context, transaction origin, etc.)
• Manages account nonce updates
• Handles value transfers between accounts
• Delegates to either _executeCall or _executeCreate based on whether the message has a to address
• Both _executeCall and _executeCreate call into runInterpreter to actually execute the bytecode
• Processes any errors or exceptions
• Manages selfdestruct sets and created contract addresses
• Commits or reverts state changes based on execution result
• Triggers events (beforeMessage, afterMessage)

The runCode method is a helper for directly running EVM bytecode (e.g., for testing or utility purposes) without the full message/transaction context:

• Sets up a minimal message context for code execution
• Directly calls runInterpreter to execute the provided bytecode
• Does not go through the full message handling logic of runCall

The runInterpreter method is used by both runCall (via _executeCall/_executeCreate) and runCode to process the actual bytecode.

The Interpreter class is the core bytecode processor:

• Manages execution state (program counter, stack, memory, gas)
• Executes a loop that:
  • Analyzes jump destinations
  • Fetches the next opcode
  • Calculates gas costs (static and dynamic)
  • Executes the opcode handler
  • Updates the program counter
  • Emits step events for debugging/tracing
• Handles stack, memory, and storage operations
• Processes call and creation operations by delegating back to the EVM

Each opcode has an associated handler function that:

• Validates inputs
• Calculates dynamic gas costs
• Performs the opcode's logic (stack operations, memory operations, etc.)
• Updates the EVM state
• The program counter is incremented in between the execution of the gas handler and opcode logic handler functions, this should be considered e.g. if parsing immediate input parameters
• Special opcodes like CALL, CREATE, DELEGATECALL create a new message and call back to the EVM's runCall method

• State changes are tracked in a journal system
• The journal supports checkpointing and reversion
• Transient storage (EIP-1153) has its own checkpoint mechanism
• When a message completes successfully, changes are committed to the state
• On failure (exceptions), changes are reverted

This layered architecture provides separation of concerns while allowing for the complex interactions needed to execute smart contracts on the Ethereum platform.

The EthereumJS EVM comes with build-in profiling capabilities to detect performance bottlenecks and to generally support the targeted evolution of the JavaScript EVM performance.

While the EVM has a dedicated profiler setting to activate, the profiler can best and most useful be run through the EthereumJS client since this gives the most realistic conditions providing both real-world txs and a meaningful state size.

To repeatedly run the EVM profiler within the client sync the client on mainnet or a larger testnet to the desired block. Then the profiler should be run without sync (to not distort the results) by using the --executeBlocks and the --vmProfileBlocks (or --vmProfileTxs) flags in conjunction like:

npm run client:start -- --sync=none --vmProfileBlocks --executeBlocks=962720

This will give a profile output like the following:

The total (ms) column gives you a good overview what takes the most significant amount of time, to be put in relation with the number of calls.

The number to optimize for is the Mgas/s value. This value indicates how much gas (being a measure for the computational cost for an opcode) can be processed by the second.

A good measure to putting this relation with is by taking both the Ethereum gas limit (the max amount of "computation" per block) and the time/slot into account. With a gas limit of 30 Mio and a 12 sec slot time this leads to a following (very) minimum Mgas/s value:

30M / 12 sec = 2.5 Million gas per second

Note that this is nevertheless a very theoretical value but pretty valuable for some first rough orientation though.

Another note: profiler results for at least some opcodes are heavily distorted, first to mention the SSTORE opcode where the major "cost" occurs after block execution on checkpoint commit, which is not taken into account by the profiler.

Generally all results should rather encourage and need "self thinking" 😋 and are not suited to be blindly taken over without a deeper understanding/grasping of the underlying measurement conditions.

Happy EVM Profiling! 🎉 🤩

See @ethereumjs/vm README.

The EthereumJS GitHub organization and its repositories are managed by the Ethereum Foundation JavaScript team, see our website for a team introduction. If you want to join for work or carry out improvements on the libraries see the developer docs for an overview of current standards and tools and review our code of conduct.

MPL-2.0