diff --git a/libs/remix-lib/src/execution/eventsDecoder.ts b/libs/remix-lib/src/execution/eventsDecoder.ts
index a6c0454736..debbd37440 100644
--- a/libs/remix-lib/src/execution/eventsDecoder.ts
+++ b/libs/remix-lib/src/execution/eventsDecoder.ts
@@ -1,6 +1,6 @@
 'use strict'
 import { ethers } from 'ethers'
-const txHelper = require('./txHelper')
+import { visitContracts } from './txHelper'
 
 /**
   * Register to txListener and extract events
@@ -50,7 +50,7 @@ export class EventsDecoder {
 
   _eventsABI (compiledContracts) {
     const eventsABI = {}
-    txHelper.visitContracts(compiledContracts, (contract) => {
+    visitContracts(compiledContracts, (contract) => {
       eventsABI[contract.name] = this._eventABI(contract.object)
     })
     return eventsABI
diff --git a/libs/remix-lib/src/execution/execution-context.ts b/libs/remix-lib/src/execution/execution-context.ts
index 611693c3d0..a40b550b60 100644
--- a/libs/remix-lib/src/execution/execution-context.ts
+++ b/libs/remix-lib/src/execution/execution-context.ts
@@ -3,14 +3,12 @@
 import Web3 from 'web3'
 const EventManager = require('../eventManager')
 const EthJSVM = require('ethereumjs-vm').default
-const ethUtil = require('ethereumjs-util')
+import { rlp, keccak, bufferToHex } from 'ethereumjs-util'
 const StateManager = require('ethereumjs-vm/dist/state/stateManager').default
 const Web3VMProvider = require('../web3Provider/web3VmProvider')
 
 const LogsManager = require('./logsManager.js')
 
-const rlp = ethUtil.rlp
-
 let web3
 if (typeof window !== 'undefined' && typeof window['ethereum'] !== 'undefined') {
   var injectedProvider = window['ethereum']
@@ -32,7 +30,7 @@ class StateManagerCommonStorageDump extends StateManager {
   }
 
   putContractStorage (address, key, value, cb) {
-    this.keyHashes[ethUtil.keccak(key).toString('hex')] = ethUtil.bufferToHex(key)
+    this.keyHashes[keccak(key).toString('hex')] = bufferToHex(key)
     super.putContractStorage(address, key, value, cb)
   }
 
diff --git a/libs/remix-lib/src/execution/txListener.ts b/libs/remix-lib/src/execution/txListener.ts
index 590fbfe4f8..e8bd2953d4 100644
--- a/libs/remix-lib/src/execution/txListener.ts
+++ b/libs/remix-lib/src/execution/txListener.ts
@@ -1,13 +1,13 @@
 'use strict'
 import async from 'async'
 import { ethers } from 'ethers'
-const ethJSUtil = require('ethereumjs-util')
+import { toBuffer } from 'ethereumjs-util'
 const EventManager = require('../eventManager')
 const codeUtil = require('../util')
 
-const defaultExecutionContext = require('./execution-context')
-const txFormat = require('./txFormat')
-const txHelper = require('./txHelper')
+import  { ExecutionContext } from './execution-context'
+import  { decodeResponse } from './txFormat'
+import  { getFunction, getReceiveInterface, getConstructorInterface, visitContracts, makeFullTypeDefinition } from './txHelper'
 
 function addExecutionCosts(txResult, tx) {
   if (txResult && txResult.result) {
@@ -26,7 +26,7 @@ function addExecutionCosts(txResult, tx) {
   * trigger 'newBlock'
   *
   */
-class TxListener {
+export class TxListener {
 
   event
   executionContext
@@ -42,7 +42,7 @@ class TxListener {
   constructor (opt, executionContext) {
     this.event = new EventManager()
     // has a default for now for backwards compatability
-    this.executionContext = executionContext || defaultExecutionContext
+    this.executionContext = executionContext || new ExecutionContext()
     this._api = opt.api
     this._resolvedTransactions = {}
     this._resolvedContracts = {}
@@ -71,7 +71,7 @@ class TxListener {
         input: data,
         hash: txResult.transactionHash ? txResult.transactionHash : 'call' + (from || '') + to + data,
         isCall: true,
-        returnValue: this.executionContext.isVM() ? txResult.result.execResult.returnValue : ethJSUtil.toBuffer(txResult.result),
+        returnValue: this.executionContext.isVM() ? txResult.result.execResult.returnValue : toBuffer(txResult.result),
         envMode: this.executionContext.getProvider()
       }
 
@@ -289,7 +289,7 @@ class TxListener {
       const methodIdentifiers = contract.object.evm.methodIdentifiers
       for (let fn in methodIdentifiers) {
         if (methodIdentifiers[fn] === inputData.substring(0, 8)) {
-          const fnabi = txHelper.getFunction(abi, fn)
+          const fnabi = getFunction(abi, fn)
           this._resolvedTransactions[tx.hash] = {
             contractName: contract.name,
             to: tx.to,
@@ -297,13 +297,13 @@ class TxListener {
             params: this._decodeInputParams(inputData.substring(8), fnabi)
           }
           if (tx.returnValue) {
-            this._resolvedTransactions[tx.hash].decodedReturnValue = txFormat.decodeResponse(tx.returnValue, fnabi)
+            this._resolvedTransactions[tx.hash].decodedReturnValue = decodeResponse(tx.returnValue, fnabi)
           }
           return this._resolvedTransactions[tx.hash]
         }
       }
       // receive function
-      if (!inputData && txHelper.getReceiveInterface(abi)) {
+      if (!inputData && getReceiveInterface(abi)) {
         this._resolvedTransactions[tx.hash] = {
           contractName: contract.name,
           to: tx.to,
@@ -323,7 +323,7 @@ class TxListener {
       const bytecode = contract.object.evm.bytecode.object
       let params = null
       if (bytecode && bytecode.length) {
-        params = this._decodeInputParams(inputData.substring(bytecode.length), txHelper.getConstructorInterface(abi))
+        params = this._decodeInputParams(inputData.substring(bytecode.length), getConstructorInterface(abi))
       }
       this._resolvedTransactions[tx.hash] = {
         contractName: contract.name,
@@ -337,7 +337,7 @@ class TxListener {
 
   _tryResolveContract (codeToResolve, compiledContracts, isCreation) {
     let found = null
-    txHelper.visitContracts(compiledContracts, (contract) => {
+    visitContracts(compiledContracts, (contract) => {
       const bytes = isCreation ? contract.object.evm.bytecode.object : contract.object.evm.deployedBytecode.object
       if (codeUtil.compareByteCode(codeToResolve, '0x' + bytes)) {
         found = contract
@@ -348,13 +348,13 @@ class TxListener {
   }
 
   _decodeInputParams (data, abi) {
-    data = ethJSUtil.toBuffer('0x' + data)
+    data = toBuffer('0x' + data)
     if (!data.length) data = new Uint8Array(32 * abi.inputs.length) // ensuring the data is at least filled by 0 cause `AbiCoder` throws if there's not engouh data
 
     const inputTypes = []
     for (let i = 0; i < abi.inputs.length; i++) {
       const type = abi.inputs[i].type
-      inputTypes.push(type.indexOf('tuple') === 0 ? txHelper.makeFullTypeDefinition(abi.inputs[i]) : type)
+      inputTypes.push(type.indexOf('tuple') === 0 ? makeFullTypeDefinition(abi.inputs[i]) : type)
     }
     const abiCoder = new ethers.utils.AbiCoder()
     const decoded = abiCoder.decode(inputTypes, data)
@@ -365,5 +365,3 @@ class TxListener {
     return ret
   }
 }
-
-module.exports = TxListener
diff --git a/libs/remix-lib/src/execution/txRunner.ts b/libs/remix-lib/src/execution/txRunner.ts
index a4e3e3f588..0b325add04 100644
--- a/libs/remix-lib/src/execution/txRunner.ts
+++ b/libs/remix-lib/src/execution/txRunner.ts
@@ -1,8 +1,8 @@
 'use strict'
-const EthJSTX = require('ethereumjs-tx').Transaction
-const EthJSBlock = require('ethereumjs-block')
+import { Transaction } from 'ethereumjs-tx'
+import { Block } from 'ethereumjs-block'
 import { BN } from 'ethereumjs-util'
-const defaultExecutionContext = require('./execution-context')
+import  { ExecutionContext } from './execution-context'
 const EventManager = require('../eventManager')
 
 class TxRunner {
@@ -20,7 +20,7 @@ class TxRunner {
   constructor (vmaccounts, api, executionContext) {
     this.event = new EventManager()
     // has a default for now for backwards compatability
-    this.executionContext = executionContext || defaultExecutionContext
+    this.executionContext = executionContext || new ExecutionContext()
     this._api = api
     this.blockNumber = 0
     this.runAsync = true
@@ -117,7 +117,7 @@ class TxRunner {
         // See https://github.com/ethereumjs/ethereumjs-tx/blob/master/docs/classes/transaction.md#constructor
         // for initialization fields and their types
         value = value ? parseInt(value) : 0
-        const tx = new EthJSTX({
+        const tx = new Transaction({
           nonce: new BN(res.nonce),
           gasPrice: '0x1',
           gasLimit: gasLimit,
@@ -128,7 +128,7 @@ class TxRunner {
         tx.sign(account.privateKey)
         const coinbases = ['0x0e9281e9c6a0808672eaba6bd1220e144c9bb07a', '0x8945a1288dc78a6d8952a92c77aee6730b414778', '0x94d76e24f818426ae84aa404140e8d5f60e10e7e']
         const difficulties = [new BN('69762765929000', 10), new BN('70762765929000', 10), new BN('71762765929000', 10)]
-        const block = new EthJSBlock({
+        const block = new Block({
           header: {
             timestamp: timestamp || (new Date().getTime() / 1000 | 0),
             number: self.blockNumber,
@@ -166,7 +166,7 @@ class TxRunner {
       this.executionContext.trackTx('0x' + tx.hash().toString('hex'), block)
       callback(null, {
         result: result,
-        transactionHash: ethJSUtil.bufferToHex(Buffer.from(tx.hash()))
+        transactionHash: bufferToHex(Buffer.from(tx.hash()))
       })
     }).catch(function (err) {
       callback(err)
diff --git a/libs/remix-lib/src/execution/typeConversion.ts b/libs/remix-lib/src/execution/typeConversion.ts
index 04559eb8f6..207057e7f9 100644
--- a/libs/remix-lib/src/execution/typeConversion.ts
+++ b/libs/remix-lib/src/execution/typeConversion.ts
@@ -1,35 +1,33 @@
 'use strict'
-const ethJSUtil = require('ethereumjs-util')
-const BN = ethJSUtil.BN
+import  { BN, bufferToHex } from 'ethereumjs-util'
 
-module.exports = {
-  toInt: (h) => {
-    if (h.indexOf && h.indexOf('0x') === 0) {
-      return (new BN(h.replace('0x', ''), 16)).toString(10)
-    } else if (h.constructor && h.constructor.name === 'BigNumber' || BN.isBN(h)) {
-      return h.toString(10)
-    }
-    return h
-  },
-  stringify: stringify
+export function toInt (h) {
+  if (h.indexOf && h.indexOf('0x') === 0) {
+    return (new BN(h.replace('0x', ''), 16)).toString(10)
+  } else if (h.constructor && h.constructor.name === 'BigNumber' || BN.isBN(h)) {
+    return h.toString(10)
+  }
+  return h
 }
+  
+export var stringify = convertToString
 
-function stringify (v) {
+function convertToString (v) {
   try {
     if (v instanceof Array) {
       const ret = []
       for (var k in v) {
-        ret.push(stringify(v[k]))
+        ret.push(convertToString(v[k]))
       }
       return ret
     } else if (BN.isBN(v) || (v.constructor && v.constructor.name === 'BigNumber')) {
       return v.toString(10)
     } else if (v._isBuffer) {
-      return ethJSUtil.bufferToHex(v)
+      return bufferToHex(v)
     } else if (typeof v === 'object') {
       const retObject = {}
       for (let i in v) {
-        retObject[i] = stringify(v[i])
+        retObject[i] = convertToString(v[i])
       }
       return retObject
     } else {