diff --git a/src/app/tabs/run-tab.js b/src/app/tabs/run-tab.js
index c3e4a48609..29a21af149 100644
--- a/src/app/tabs/run-tab.js
+++ b/src/app/tabs/run-tab.js
@@ -1,7 +1,7 @@
 var $ = require('jquery')
 var yo = require('yo-yo')
 var EventManager = require('../../lib/events')
-var globlalRegistry = require('../../global/registry')
+var globalRegistry = require('../../global/registry')
 var executionContext = require('../../execution-context')
 var Card = require('../ui/card')
 var css = require('./styles/run-tab-styles')
@@ -15,177 +15,183 @@ var ContractDropdownUI = require('./runTab/contractDropdown.js')
 var Recorder = require('./runTab/model/recorder.js')
 var RecorderUI = require('./runTab/recorder.js')
 
-function runTab (opts, localRegistry) {
-  var self = this
-  self.event = new EventManager()
-  self._view = {}
-  self.data = {
-    count: 0,
-    text: `All transactions (deployed contracts and function executions) in this environment can be saved and replayed in
-    another environment. e.g Transactions created in Javascript VM can be replayed in the Injected Web3.`
-  }
-  self._components = {}
-  self._components.registry = localRegistry || globlalRegistry
-  self._components.transactionContextAPI = {
-    getAddress: (cb) => {
-      cb(null, $('#txorigin').val())
-    },
-    getValue: (cb) => {
-      try {
-        var number = document.querySelector('#value').value
-        var select = document.getElementById('unit')
-        var index = select.selectedIndex
-        var selectedUnit = select.querySelectorAll('option')[index].dataset.unit
-        var unit = 'ether' // default
-        if (['ether', 'finney', 'gwei', 'wei'].indexOf(selectedUnit) >= 0) {
-          unit = selectedUnit
+class RunTab {
+
+  constructor (opts, localRegistry) {
+    var self = this
+    self.event = new EventManager()
+    self._view = {}
+    self.data = {
+      count: 0,
+      text: `All transactions (deployed contracts and function executions) in this environment can be saved and replayed in
+      another environment. e.g Transactions created in Javascript VM can be replayed in the Injected Web3.`
+    }
+    self._components = {}
+    self._components.registry = localRegistry || globalRegistry
+    self._components.transactionContextAPI = {
+      getAddress: (cb) => {
+        cb(null, $('#txorigin').val())
+      },
+      getValue: (cb) => {
+        try {
+          var number = document.querySelector('#value').value
+          var select = document.getElementById('unit')
+          var index = select.selectedIndex
+          var selectedUnit = select.querySelectorAll('option')[index].dataset.unit
+          var unit = 'ether' // default
+          if (['ether', 'finney', 'gwei', 'wei'].indexOf(selectedUnit) >= 0) {
+            unit = selectedUnit
+          }
+          cb(null, executionContext.web3().toWei(number, unit))
+        } catch (e) {
+          cb(e)
         }
-        cb(null, executionContext.web3().toWei(number, unit))
-      } catch (e) {
-        cb(e)
+      },
+      getGasLimit: (cb) => {
+        cb(null, $('#gasLimit').val())
       }
-    },
-    getGasLimit: (cb) => {
-      cb(null, $('#gasLimit').val())
     }
-  }
-  // dependencies
-  self._deps = {
-    udapp: self._components.registry.get('udapp').api,
-    udappUI: self._components.registry.get('udappUI').api,
-    config: self._components.registry.get('config').api,
-    fileManager: self._components.registry.get('filemanager').api,
-    editor: self._components.registry.get('editor').api,
-    logCallback: self._components.registry.get('logCallback').api,
-    filePanel: self._components.registry.get('filepanel').api,
-    pluginManager: self._components.registry.get('pluginmanager').api,
-    compilersArtefacts: self._components.registry.get('compilersartefacts').api
-  }
-  self._deps.udapp.resetAPI(self._components.transactionContextAPI)
-  self._view.recorderCount = yo`<span>0</span>`
-  self._view.instanceContainer = yo`<div class="${css.instanceContainer}"></div>`
-  self._view.clearInstanceElement = yo`
-    <i class="${css.clearinstance} ${css.icon} fa fa-trash" onclick=${() => self.event.trigger('clearInstance', [])}
-    title="Clear instances list and reset recorder" aria-hidden="true">
-  </i>`
-  self._view.instanceContainerTitle = yo`
-    <div class=${css.instanceContainerTitle}
-      title="Autogenerated generic user interfaces for interaction with deployed contracts">
-      Deployed Contracts
-      ${self._view.clearInstanceElement}
-    </div>`
-  self._view.noInstancesText = yo`
-    <div class="${css.noInstancesText}">
-      Currently you have no contract instances to interact with.
-    </div>`
-
-  var container = yo`<div class="${css.runTabView}" id="runTabView" ></div>`
-
-  var recorder = new Recorder(self._deps.udapp, self._deps.fileManager, self._deps.config)
-  recorder.event.register('newTxRecorded', (count) => {
-    this.data.count = count
-    this._view.recorderCount.innerText = count
-  })
-  recorder.event.register('cleared', () => {
-    this.data.count = 0
-    this._view.recorderCount.innerText = 0
-  })
-  executionContext.event.register('contextChanged', recorder.clearAll.bind(recorder))
-  self.event.register('clearInstance', recorder.clearAll.bind(recorder))
-
-  var recorderInterface = new RecorderUI(recorder, self._deps.logCallback)
-
-  recorderInterface.event.register('newScenario', (abi, address, contractName) => {
-    var noInstancesText = this._view.noInstancesText
-    if (noInstancesText.parentNode) { noInstancesText.parentNode.removeChild(noInstancesText) }
-    this._view.instanceContainer.appendChild(this._deps.udappUI.renderInstanceFromABI(abi, address, contractName))
-  })
-
-  recorderInterface.render()
-
-  self._view.collapsedView = yo`
-    <div class=${css.recorderCollapsedView}>
-      <div class=${css.recorderCount}>${self._view.recorderCount}</div>
-    </div>`
-
-  self._view.expandedView = yo`
-    <div class=${css.recorderExpandedView}>
-      <div class=${css.recorderDescription}>
-        ${self.data.text}
-      </div>
-      <div class="${css.transactionActions}">
-        ${recorderInterface.recordButton}
-        ${recorderInterface.runButton}
+    // dependencies
+    self._deps = {
+      udapp: self._components.registry.get('udapp').api,
+      udappUI: self._components.registry.get('udappUI').api,
+      config: self._components.registry.get('config').api,
+      fileManager: self._components.registry.get('filemanager').api,
+      editor: self._components.registry.get('editor').api,
+      logCallback: self._components.registry.get('logCallback').api,
+      filePanel: self._components.registry.get('filepanel').api,
+      pluginManager: self._components.registry.get('pluginmanager').api,
+      compilersArtefacts: self._components.registry.get('compilersartefacts').api
+    }
+    self._deps.udapp.resetAPI(self._components.transactionContextAPI)
+    self._view.recorderCount = yo`<span>0</span>`
+    self._view.instanceContainer = yo`<div class="${css.instanceContainer}"></div>`
+    self._view.clearInstanceElement = yo`
+      <i class="${css.clearinstance} ${css.icon} fa fa-trash" onclick=${() => self.event.trigger('clearInstance', [])}
+      title="Clear instances list and reset recorder" aria-hidden="true">
+    </i>`
+    self._view.instanceContainerTitle = yo`
+      <div class=${css.instanceContainerTitle}
+        title="Autogenerated generic user interfaces for interaction with deployed contracts">
+        Deployed Contracts
+        ${self._view.clearInstanceElement}
+      </div>`
+    self._view.noInstancesText = yo`
+      <div class="${css.noInstancesText}">
+        Currently you have no contract instances to interact with.
+      </div>`
+
+    var container = yo`<div class="${css.runTabView}" id="runTabView" ></div>`
+
+    var recorder = new Recorder(self._deps.udapp, self._deps.fileManager, self._deps.config)
+    recorder.event.register('newTxRecorded', (count) => {
+      this.data.count = count
+      this._view.recorderCount.innerText = count
+    })
+    recorder.event.register('cleared', () => {
+      this.data.count = 0
+      this._view.recorderCount.innerText = 0
+    })
+    executionContext.event.register('contextChanged', recorder.clearAll.bind(recorder))
+    self.event.register('clearInstance', recorder.clearAll.bind(recorder))
+
+    var recorderInterface = new RecorderUI(recorder, self._deps.logCallback)
+
+    recorderInterface.event.register('newScenario', (abi, address, contractName) => {
+      var noInstancesText = this._view.noInstancesText
+      if (noInstancesText.parentNode) { noInstancesText.parentNode.removeChild(noInstancesText) }
+      this._view.instanceContainer.appendChild(this._deps.udappUI.renderInstanceFromABI(abi, address, contractName))
+    })
+
+    recorderInterface.render()
+
+    self._view.collapsedView = yo`
+      <div class=${css.recorderCollapsedView}>
+        <div class=${css.recorderCount}>${self._view.recorderCount}</div>
+      </div>`
+
+    self._view.expandedView = yo`
+      <div class=${css.recorderExpandedView}>
+        <div class=${css.recorderDescription}>
+          ${self.data.text}
         </div>
-      </div>
-    </div>`
+        <div class="${css.transactionActions}">
+          ${recorderInterface.recordButton}
+          ${recorderInterface.runButton}
+          </div>
+        </div>
+      </div>`
+
+    self.recorderOpts = {
+      title: 'Transactions recorded:',
+      collapsedView: self._view.collapsedView
+    }
 
-  self.recorderOpts = {
-    title: 'Transactions recorded:',
-    collapsedView: self._view.collapsedView
+    var recorderCard = new Card({}, {}, self.recorderOpts)
+    recorderCard.event.register('expandCollapseCard', (arrow, body, status) => {
+      body.innerHTML = ''
+      status.innerHTML = ''
+      if (arrow === 'down') {
+        status.appendChild(self._view.collapsedView)
+        body.appendChild(self._view.expandedView)
+      } else if (arrow === 'up') {
+        status.appendChild(self._view.collapsedView)
+      }
+    })
+
+    var settings = new Settings(self._deps.udapp)
+    var settingsUI = new SettingsUI(settings)
+
+    self.event.register('clearInstance', () => {
+      this._view.instanceContainer.innerHTML = '' // clear the instances list
+      this._view.instanceContainer.appendChild(self._view.instanceContainerTitle)
+      this._view.instanceContainer.appendChild(self._view.noInstancesText)
+    })
+    settingsUI.event.register('clearInstance', () => {
+      this.event.trigger('clearInstance', [])
+    })
+
+    var dropdownLogic = new DropdownLogic(
+      this._deps.fileManager,
+      this._deps.pluginManager,
+      this._deps.compilersArtefacts,
+      this._deps.compiler,
+      this._deps.config,
+      this._deps.editor,
+      this._deps.udapp,
+      this._deps.filePanel
+    )
+    var contractDropdownUI = new ContractDropdownUI(dropdownLogic, this._deps.logCallback)
+
+    contractDropdownUI.event.register('clearInstance', () => {
+      var noInstancesText = this._view.noInstancesText
+      if (noInstancesText.parentNode) { noInstancesText.parentNode.removeChild(noInstancesText) }
+    })
+    contractDropdownUI.event.register('newContractABIAdded', (abi, address) => {
+      this._view.instanceContainer.appendChild(this._deps.udappUI.renderInstanceFromABI(abi, address, address))
+    })
+    contractDropdownUI.event.register('newContractInstanceAdded', (contractObject, address, value) => {
+      this._view.instanceContainer.appendChild(this._deps.udappUI.renderInstance(contractObject, address, value))
+    })
+
+    this._view.instanceContainer.appendChild(this._view.instanceContainerTitle)
+    this._view.instanceContainer.appendChild(this._view.noInstancesText)
+
+    var el = yo`
+    <div>
+      ${settingsUI.render()}
+      ${contractDropdownUI.render()}
+      ${recorderCard.render()}
+      ${self._view.instanceContainer}
+    </div>
+    `
+    container.appendChild(el)
+    this.container = container
   }
 
-  var recorderCard = new Card({}, {}, self.recorderOpts)
-  recorderCard.event.register('expandCollapseCard', (arrow, body, status) => {
-    body.innerHTML = ''
-    status.innerHTML = ''
-    if (arrow === 'down') {
-      status.appendChild(self._view.collapsedView)
-      body.appendChild(self._view.expandedView)
-    } else if (arrow === 'up') {
-      status.appendChild(self._view.collapsedView)
-    }
-  })
-
-  var settings = new Settings(self._deps.udapp)
-  var settingsUI = new SettingsUI(settings)
-
-  self.event.register('clearInstance', () => {
-    this._view.instanceContainer.innerHTML = '' // clear the instances list
-    this._view.instanceContainer.appendChild(self._view.instanceContainerTitle)
-    this._view.instanceContainer.appendChild(self._view.noInstancesText)
-  })
-  settingsUI.event.register('clearInstance', () => {
-    this.event.trigger('clearInstance', [])
-  })
-
-  var dropdownLogic = new DropdownLogic(
-    this._deps.fileManager,
-    this._deps.pluginManager,
-    this._deps.compilersArtefacts,
-    this._deps.compiler,
-    this._deps.config,
-    this._deps.editor,
-    this._deps.udapp,
-    this._deps.filePanel
-  )
-  var contractDropdownUI = new ContractDropdownUI(dropdownLogic, this._deps.logCallback)
-
-  contractDropdownUI.event.register('clearInstance', () => {
-    var noInstancesText = this._view.noInstancesText
-    if (noInstancesText.parentNode) { noInstancesText.parentNode.removeChild(noInstancesText) }
-  })
-  contractDropdownUI.event.register('newContractABIAdded', (abi, address) => {
-    this._view.instanceContainer.appendChild(this._deps.udappUI.renderInstanceFromABI(abi, address, address))
-  })
-  contractDropdownUI.event.register('newContractInstanceAdded', (contractObject, address, value) => {
-    this._view.instanceContainer.appendChild(this._deps.udappUI.renderInstance(contractObject, address, value))
-  })
-
-  this._view.instanceContainer.appendChild(this._view.instanceContainerTitle)
-  this._view.instanceContainer.appendChild(this._view.noInstancesText)
-
-  var el = yo`
-  <div>
-    ${settingsUI.render()}
-    ${contractDropdownUI.render()}
-    ${recorderCard.render()}
-    ${self._view.instanceContainer}
-  </div>
-  `
-  container.appendChild(el)
-
-  return { render () { return container } }
+  render () {
+    return this.container
+  }
 }
 
-module.exports = runTab
+module.exports = RunTab