diff --git a/package.json b/package.json
index 14cf71a..c5918cf 100644
--- a/package.json
+++ b/package.json
@@ -23,6 +23,7 @@
   },
   "devDependencies": {
     "@types/chrome": "^0.0.77",
+    "@types/ini": "^1.3.30",
     "@types/nprogress": "^0.0.29",
     "@types/react": "^16.8.2",
     "@types/react-dom": "^16.8.0",
diff --git a/src/components/FileExplorer.tsx b/src/components/FileExplorer.tsx
index 65f98cb..b2fa573 100644
--- a/src/components/FileExplorer.tsx
+++ b/src/components/FileExplorer.tsx
@@ -6,28 +6,19 @@ import Node from 'components/Node'
 import LoadingIndicator from 'components/LoadingIndicator'
 import cx from 'utils/cx'
 import { TreeData, MetaData, VisibleNodes } from './SideBar'
+import { ConnectorState } from 'driver/core/FileExplorer'
 
-type Props = {
+export type Props = {
   treeData: TreeData
   metaData: MetaData
-  visibleNodes: VisibleNodes
   freeze: boolean
-
-  stateText: string
-
-  init: () => void
-  execAfterRender: () => void
-  handleKeyDown: React.KeyboardEventHandler
-  handleSearchKeyChange: React.FormEventHandler
-  onNodeClick: Node['props']['onClick']
+  compressSingletonFolder: boolean
+  accessToken: string
   toggleShowSettings: React.MouseEventHandler
-  onFocusSearchBar: React.FocusEventHandler
-  setUpTree: (treeData?: TreeData) => void
 }
 
-@(connect(FileExplorerCore) as any)
-export default class FileExplorer extends React.Component<Props> {
-  static defaultProps: Partial<Props> = {
+class FileExplorer extends React.Component<Props & ConnectorState> {
+  static defaultProps: Partial<Props & ConnectorState> = {
     treeData: null,
     metaData: null,
     freeze: false,
@@ -45,7 +36,7 @@ export default class FileExplorer extends React.Component<Props> {
     execAfterRender()
   }
 
-  componentWillReceiveProps(nextProps: Props) {
+  componentWillReceiveProps(nextProps: Props & ConnectorState) {
     if (nextProps.treeData !== this.props.treeData) {
       const { setUpTree } = nextProps
       setUpTree()
@@ -110,3 +101,5 @@ export default class FileExplorer extends React.Component<Props> {
     )
   }
 }
+
+export default connect<Props, ConnectorState>(FileExplorerCore)(FileExplorer)
diff --git a/src/driver/core/FileExplorer.js b/src/driver/core/FileExplorer.js
deleted file mode 100644
index e1cd0f0..0000000
--- a/src/driver/core/FileExplorer.js
+++ /dev/null
@@ -1,284 +0,0 @@
-import ini from 'ini'
-import DOMHelper from 'utils/DOMHelper'
-import treeParser from 'utils/treeParser'
-import URLHelper from 'utils/URLHelper'
-import VisibleNodesGenerator from 'utils/VisibleNodesGenerator'
-import GitHubHelper from 'utils/GitHubHelper'
-
-function getVisibleParentNode(nodes, focusedNode, depths) {
-  const focusedNodeIndex = nodes.indexOf(focusedNode)
-  const focusedNodeDepth = depths.get(focusedNode)
-  let indexOfParentNode = focusedNodeIndex - 1
-  while (
-    indexOfParentNode !== -1 &&
-    depths.get(nodes[indexOfParentNode]) >= focusedNodeDepth
-  ) {
-    --indexOfParentNode
-  }
-  const parentNode = nodes[indexOfParentNode]
-  return parentNode
-}
-
-const tasksAfterRender = []
-const visibleNodesGenerator = new VisibleNodesGenerator()
-
-const init = dispatch => () => dispatch(async () => {
-  dispatch(setStateText, 'Fetching File List...')
-})
-
-function resolveGitModules(root, blobData) {
-  if (blobData) {
-    if (blobData.encoding === 'base64') {
-      const content = atob(blobData.content)
-      const parsed = ini.parse(content)
-      Object.values(parsed).map(value => {
-        const { url, path } = value
-        // for now, handle modules at root only
-        const node = root.contents.find(node => node.path === path)
-        if (node) {
-          node.url = url
-        }
-      })
-    }
-  }
-}
-
-const setUpTree = dispatch => () => dispatch(async (state, { treeData, metaData, compressSingletonFolder, accessToken }) => {
-  if (!treeData) return
-  dispatch(setStateText, 'Rendering File List...')
-  const { root, gitModules } = treeParser.parse(treeData, metaData)
-
-  if (gitModules) {
-    const blobData = await GitHubHelper.getBlobData({
-      userName: metaData.userName,
-      repoName: metaData.repoName,
-      fileSHA: gitModules.sha,
-      accessToken,
-    })
-
-    resolveGitModules(root, blobData)
-  }
-
-  visibleNodesGenerator.setCompress(compressSingletonFolder)
-  await visibleNodesGenerator.plantTree(root)
-
-  tasksAfterRender.push(DOMHelper.focusSearchInput)
-  dispatch(setStateText, null)
-  const currentPath = URLHelper.getCurrentPath(metaData.branchName)
-  if (currentPath.length) {
-    const nodeExpandedTo = visibleNodesGenerator.expandTo(currentPath.join('/'))
-    if (nodeExpandedTo) {
-      visibleNodesGenerator.focusNode(nodeExpandedTo)
-      const { nodes } = visibleNodesGenerator.visibleNodes
-      tasksAfterRender.push(() => DOMHelper.scrollToNodeElement(nodes.indexOf(nodeExpandedTo)))
-    }
-  }
-  dispatch(updateVisibleNodes)
-})
-
-const execAfterRender = dispatch => () => {
-  for (const task of tasksAfterRender) {
-    task()
-  }
-  tasksAfterRender.length = 0
-}
-
-const setStateText = dispatch => text => dispatch({
-  stateText: text,
-})
-
-const handleKeyDown = dispatch => event => dispatch(({ visibleNodes: { nodes, focusedNode, expandedNodes, depths } }) => {
-  function handleVerticalMove(index) {
-    if (0 <= index && index < nodes.length) {
-      DOMHelper.focusFileExplorer()
-      dispatch(focusNode, nodes[index])
-    } else {
-      DOMHelper.focusSearchInput()
-      dispatch(focusNode, null)
-    }
-  }
-
-  const { key } = event
-  // prevent document body scrolling if the keypress results in Gitako action
-  let muteEvent = true
-  if (focusedNode) {
-    const focusedNodeIndex = nodes.indexOf(focusedNode)
-    switch (key) {
-      case 'ArrowUp':
-        // focus on previous node
-        handleVerticalMove(focusedNodeIndex - 1)
-        break
-
-      case 'ArrowDown':
-        // focus on next node
-        handleVerticalMove(focusedNodeIndex + 1)
-        break
-
-      case 'ArrowLeft':
-        // collapse node or go to parent node
-        if (expandedNodes.has(focusedNode)) {
-          dispatch(setExpand, focusedNode, false)
-        } else {
-          // go forward to the start of the list, find the closest node with lower depth
-          const parentNode = getVisibleParentNode(nodes, focusedNode, depths)
-          if (parentNode) {
-            dispatch(focusNode, parentNode)
-          }
-        }
-        break
-
-      // consider the two keys as 'confirm' key
-      case 'ArrowRight':
-        // expand node or focus on first content node or redirect to file page
-        if (focusedNode.type === 'tree') {
-          if (expandedNodes.has(focusedNode)) {
-            const nextNode = nodes[focusedNodeIndex + 1]
-            if (depths.get(nextNode) > depths.get(focusedNode)) {
-              dispatch(focusNode, nextNode)
-            }
-          } else {
-            dispatch(setExpand, focusedNode, true)
-          }
-        } else if (focusedNode.type === 'blob') {
-          DOMHelper.loadWithPJAX(focusedNode.url)
-        } else if (focusedNode.type === 'commit') {
-          window.open(focusedNode.url)
-        }
-        break
-      case 'Enter':
-        // expand node or redirect to file page
-        if (focusedNode.type === 'tree') {
-          dispatch(setExpand, focusedNode, true)
-        } else if (focusedNode.type === 'blob') {
-          DOMHelper.loadWithPJAX(focusedNode.url)
-        } else if (focusedNode.type === 'commit') {
-          window.open(focusedNode.url)
-        }
-        break
-      default:
-        muteEvent = false
-    }
-    if (muteEvent) {
-      event.preventDefault()
-    }
-  } else {
-    // now search input is focused
-    if (nodes.length) {
-      switch (key) {
-        case 'ArrowDown':
-          DOMHelper.focusFileExplorer()
-          dispatch(focusNode, nodes[0])
-          break
-        case 'ArrowUp':
-          DOMHelper.focusFileExplorer()
-          dispatch(focusNode, nodes[nodes.length - 1])
-          break
-        default:
-          muteEvent = false
-      }
-      if (muteEvent) {
-        event.preventDefault()
-      }
-    }
-  }
-})
-
-const onFocusSearchBar = dispatch => () => dispatch(focusNode, null)
-
-const handleSearchKeyChange = dispatch => {
-  let i = 0
-  return async event => {
-    const searchKey = event.target.value
-    const j = i += 1
-    await visibleNodesGenerator.search(searchKey)
-    if (i === j) dispatch(updateVisibleNodes)
-  }
-}
-
-const delayExpandThreshold = 400
-function shouldDelayExpand(node) {
-  return visibleNodesGenerator.visibleNodes.expandedNodes.has(node)
-    && node.contents.length > delayExpandThreshold
-}
-
-const setExpand = dispatch => (node, expand) => {
-  visibleNodesGenerator.setExpand(node, expand)
-  const applyChanges = () => dispatch(focusNode, node)
-  if (shouldDelayExpand(node)) {
-    dispatch(mountExpandingIndicator, node)
-    tasksAfterRender.push(() => setTimeout(applyChanges, 0))
-  } else {
-    applyChanges()
-  }
-}
-
-const toggleNodeExpansion = dispatch => (node, skipScrollToNode) => {
-  visibleNodesGenerator.toggleExpand(node)
-  const applyChanges = () => {
-    dispatch(focusNode, node, skipScrollToNode)
-    tasksAfterRender.push(DOMHelper.focusFileExplorer)
-  }
-  if (shouldDelayExpand(node)) {
-    dispatch(mountExpandingIndicator, node)
-    tasksAfterRender.push(() => setTimeout(applyChanges, 0))
-  } else {
-    applyChanges()
-  }
-}
-
-const focusNode = dispatch => (node, skipScroll) => dispatch(({ visibleNodes: { nodes } }) => {
-  visibleNodesGenerator.focusNode(node)
-  if (node && !skipScroll) {
-    // when focus a node not in viewport(by keyboard), scroll to it
-    const indexOfToBeFocusedNode = nodes.indexOf(node)
-    tasksAfterRender.push(() => DOMHelper.scrollToNodeElement(indexOfToBeFocusedNode))
-  }
-  dispatch(updateVisibleNodes)
-})
-
-const onNodeClick = dispatch => (node) => dispatch((state, { metaData, accessToken }) => {
-  if (node.type === 'tree') {
-    dispatch(toggleNodeExpansion, node, true)
-  } else if (node.type === 'blob') {
-    dispatch(focusNode, node, true)
-    DOMHelper.loadWithPJAX(node.url)
-  } else if (node.type === 'commit') {
-    window.open(node.url, '_blank')
-  }
-})
-
-const mountExpandingIndicator = dispatch => node => dispatch(({ visibleNodes }) => {
-  const dummyVisibleNodes = {
-    ...visibleNodes,
-    nodes: visibleNodes.nodes.slice(),
-  }
-  dummyVisibleNodes.nodes.splice(
-    dummyVisibleNodes.nodes.indexOf(node) + 1,
-    0,
-    { virtual: true, name: 'Loading', path: '-' },
-  )
-  return {
-    visibleNodes: dummyVisibleNodes
-  }
-})
-
-const updateVisibleNodes = dispatch => () => {
-  const { visibleNodes } = visibleNodesGenerator
-  dispatch({ visibleNodes })
-}
-
-export default {
-  init,
-  setUpTree,
-  execAfterRender,
-  setStateText,
-  handleKeyDown,
-  onFocusSearchBar,
-  handleSearchKeyChange,
-  setExpand,
-  toggleNodeExpansion,
-  focusNode,
-  onNodeClick,
-  updateVisibleNodes,
-  mountExpandingIndicator,
-}
diff --git a/src/driver/core/FileExplorer.ts b/src/driver/core/FileExplorer.ts
new file mode 100644
index 0000000..e593823
--- /dev/null
+++ b/src/driver/core/FileExplorer.ts
@@ -0,0 +1,307 @@
+import * as ini from 'ini'
+import DOMHelper from 'utils/DOMHelper'
+import treeParser from 'utils/treeParser'
+import URLHelper from 'utils/URLHelper'
+import VisibleNodesGenerator, { TreeNode } from 'utils/VisibleNodesGenerator'
+import GitHubHelper, { BlobData, TreeData, MetaData } from 'utils/GitHubHelper'
+import { MethodCreator } from 'driver/connect'
+import { Props } from 'components/FileExplorer'
+import Node from 'components/Node'
+import { VisibleNodes } from 'components/SideBar'
+
+export type ConnectorState = {
+  stateText: string
+  visibleNodes: VisibleNodes
+
+  init: () => void
+  execAfterRender: () => void
+  handleKeyDown: React.KeyboardEventHandler
+  handleSearchKeyChange: React.FormEventHandler
+  onNodeClick: Node['props']['onClick']
+  onFocusSearchBar: React.FocusEventHandler
+  setUpTree: (treeData?: TreeData) => void
+}
+
+type DepthMap = Map<TreeNode, number>
+
+function getVisibleParentNode(nodes: TreeNode[], focusedNode: TreeNode, depths: DepthMap) {
+  const focusedNodeIndex = nodes.indexOf(focusedNode)
+  const focusedNodeDepth = depths.get(focusedNode)
+  let indexOfParentNode = focusedNodeIndex - 1
+  while (indexOfParentNode !== -1 && depths.get(nodes[indexOfParentNode]) >= focusedNodeDepth) {
+    --indexOfParentNode
+  }
+  const parentNode = nodes[indexOfParentNode]
+  return parentNode
+}
+
+type Task = () => void
+const tasksAfterRender: (Task)[] = []
+const visibleNodesGenerator = new VisibleNodesGenerator()
+
+const init: MethodCreator = dispatch => () => dispatch.for(setStateText, 'Fetching File List...')
+
+function resolveGitModules(root: TreeNode, blobData: BlobData) {
+  if (blobData) {
+    if (blobData.encoding === 'base64') {
+      const content = atob(blobData.content)
+      const parsed = ini.parse(content)
+      Object.values(parsed).map((value: { url: string; path: string }) => {
+        const { url, path } = value
+        // for now, handle modules at root only
+        const node = root.contents.find(node => node.path === path)
+        if (node) {
+          node.url = url
+        }
+      })
+    }
+  }
+}
+
+const setUpTree: MethodCreator<Props> = dispatch => () =>
+  dispatch.prepare(async ({ treeData, metaData, compressSingletonFolder, accessToken }) => {
+    if (!treeData) return
+    dispatch.for(setStateText, 'Rendering File List...')
+    const { root, gitModules } = treeParser.parse(treeData, metaData)
+
+    if (gitModules) {
+      const blobData = await GitHubHelper.getBlobData({
+        userName: metaData.userName,
+        repoName: metaData.repoName,
+        fileSHA: gitModules.sha,
+        accessToken,
+      })
+
+      resolveGitModules(root as TreeNode, blobData)
+    }
+
+    visibleNodesGenerator.setCompress(compressSingletonFolder)
+    await visibleNodesGenerator.plantTree(root as TreeNode)
+
+    tasksAfterRender.push(DOMHelper.focusSearchInput)
+    dispatch.for(setStateText, null)
+    const currentPath = URLHelper.getCurrentPath(metaData.branchName)
+    if (currentPath.length) {
+      const nodeExpandedTo = visibleNodesGenerator.expandTo(currentPath.join('/'))
+      if (nodeExpandedTo) {
+        visibleNodesGenerator.focusNode(nodeExpandedTo)
+        const { nodes } = visibleNodesGenerator.visibleNodes
+        tasksAfterRender.push(() => DOMHelper.scrollToNodeElement(nodes.indexOf(nodeExpandedTo)))
+      }
+    }
+    dispatch.for(updateVisibleNodes)
+  })
+
+const execAfterRender: MethodCreator = dispatch => () => {
+  for (const task of tasksAfterRender) {
+    task()
+  }
+  tasksAfterRender.length = 0
+}
+
+const setStateText: MethodCreator<Props> = dispatch => (text: string) =>
+  dispatch.state({
+    stateText: text,
+  })
+
+const handleKeyDown: MethodCreator = dispatch => event =>
+  dispatch.prepare((_, { visibleNodes: { nodes, focusedNode, expandedNodes, depths } }) => {
+    function handleVerticalMove(index: number) {
+      if (0 <= index && index < nodes.length) {
+        DOMHelper.focusFileExplorer()
+        dispatch.for(focusNode, nodes[index])
+      } else {
+        DOMHelper.focusSearchInput()
+        dispatch.for(focusNode, null)
+      }
+    }
+
+    const { key } = event
+    // prevent document body scrolling if the keypress results in Gitako action
+    let muteEvent = true
+    if (focusedNode) {
+      const focusedNodeIndex = nodes.indexOf(focusedNode)
+      switch (key) {
+        case 'ArrowUp':
+          // focus on previous node
+          handleVerticalMove(focusedNodeIndex - 1)
+          break
+
+        case 'ArrowDown':
+          // focus on next node
+          handleVerticalMove(focusedNodeIndex + 1)
+          break
+
+        case 'ArrowLeft':
+          // collapse node or go to parent node
+          if (expandedNodes.has(focusedNode)) {
+            dispatch.for(setExpand, focusedNode, false)
+          } else {
+            // go forward to the start of the list, find the closest node with lower depth
+            const parentNode = getVisibleParentNode(nodes, focusedNode, depths)
+            if (parentNode) {
+              dispatch.for(focusNode, parentNode)
+            }
+          }
+          break
+
+        // consider the two keys as 'confirm' key
+        case 'ArrowRight':
+          // expand node or focus on first content node or redirect to file page
+          if (focusedNode.type === 'tree') {
+            if (expandedNodes.has(focusedNode)) {
+              const nextNode = nodes[focusedNodeIndex + 1]
+              if (depths.get(nextNode) > depths.get(focusedNode)) {
+                dispatch.for(focusNode, nextNode)
+              }
+            } else {
+              dispatch.for(setExpand, focusedNode, true)
+            }
+          } else if (focusedNode.type === 'blob') {
+            DOMHelper.loadWithPJAX(focusedNode.url)
+          } else if (focusedNode.type === 'commit') {
+            window.open(focusedNode.url)
+          }
+          break
+        case 'Enter':
+          // expand node or redirect to file page
+          if (focusedNode.type === 'tree') {
+            dispatch.for(setExpand, focusedNode, true)
+          } else if (focusedNode.type === 'blob') {
+            DOMHelper.loadWithPJAX(focusedNode.url)
+          } else if (focusedNode.type === 'commit') {
+            window.open(focusedNode.url)
+          }
+          break
+        default:
+          muteEvent = false
+      }
+      if (muteEvent) {
+        event.preventDefault()
+      }
+    } else {
+      // now search input is focused
+      if (nodes.length) {
+        switch (key) {
+          case 'ArrowDown':
+            DOMHelper.focusFileExplorer()
+            dispatch.for(focusNode, nodes[0])
+            break
+          case 'ArrowUp':
+            DOMHelper.focusFileExplorer()
+            dispatch.for(focusNode, nodes[nodes.length - 1])
+            break
+          default:
+            muteEvent = false
+        }
+        if (muteEvent) {
+          event.preventDefault()
+        }
+      }
+    }
+  })
+
+const onFocusSearchBar: MethodCreator = dispatch => () => dispatch.for(focusNode, null)
+
+const handleSearchKeyChange: MethodCreator = dispatch => {
+  let i = 0
+  return async event => {
+    const searchKey = event.target.value
+    const j = (i += 1)
+    await visibleNodesGenerator.search(searchKey)
+    if (i === j) dispatch.for(updateVisibleNodes)
+  }
+}
+
+const delayExpandThreshold = 400
+function shouldDelayExpand(node: TreeNode) {
+  return (
+    visibleNodesGenerator.visibleNodes.expandedNodes.has(node) &&
+    node.contents.length > delayExpandThreshold
+  )
+}
+
+const setExpand: MethodCreator = dispatch => (node, expand) => {
+  visibleNodesGenerator.setExpand(node, expand)
+  const applyChanges = () => dispatch.for(focusNode, node)
+  if (shouldDelayExpand(node)) {
+    dispatch.for(mountExpandingIndicator, node)
+    tasksAfterRender.push(() => setTimeout(applyChanges, 0))
+  } else {
+    applyChanges()
+  }
+}
+
+const toggleNodeExpansion: MethodCreator = dispatch => (node, skipScrollToNode) => {
+  visibleNodesGenerator.toggleExpand(node)
+  const applyChanges = () => {
+    dispatch.for(focusNode, node, skipScrollToNode)
+    tasksAfterRender.push(DOMHelper.focusFileExplorer)
+  }
+  if (shouldDelayExpand(node)) {
+    dispatch.for(mountExpandingIndicator, node)
+    tasksAfterRender.push(() => setTimeout(applyChanges, 0))
+  } else {
+    applyChanges()
+  }
+}
+
+const focusNode: MethodCreator = dispatch => (node, skipScroll) =>
+  dispatch.prepare((_, { visibleNodes: { nodes } }) => {
+    visibleNodesGenerator.focusNode(node)
+    if (node && !skipScroll) {
+      // when focus a node not in viewport(by keyboard), scroll to it
+      const indexOfToBeFocusedNode = nodes.indexOf(node)
+      tasksAfterRender.push(() => DOMHelper.scrollToNodeElement(indexOfToBeFocusedNode))
+    }
+    dispatch.for(updateVisibleNodes)
+  })
+
+const onNodeClick: MethodCreator = dispatch => node => {
+  if (node.type === 'tree') {
+    dispatch.for(toggleNodeExpansion, node, true)
+  } else if (node.type === 'blob') {
+    dispatch.for(focusNode, node, true)
+    DOMHelper.loadWithPJAX(node.url)
+  } else if (node.type === 'commit') {
+    window.open(node.url, '_blank')
+  }
+}
+
+const mountExpandingIndicator: MethodCreator = dispatch => node =>
+  dispatch.prepare((_, { visibleNodes }) => {
+    const dummyVisibleNodes = {
+      ...visibleNodes,
+      nodes: visibleNodes.nodes.slice(),
+    }
+    dummyVisibleNodes.nodes.splice(dummyVisibleNodes.nodes.indexOf(node) + 1, 0, {
+      virtual: true,
+      name: 'Loading',
+      path: '-',
+      type: 'virtual',
+    })
+    dispatch.state({
+      visibleNodes: dummyVisibleNodes,
+    })
+  })
+
+const updateVisibleNodes: MethodCreator = dispatch => () => {
+  const { visibleNodes } = visibleNodesGenerator
+  dispatch.state({ visibleNodes })
+}
+
+export default {
+  init,
+  setUpTree,
+  execAfterRender,
+  setStateText,
+  handleKeyDown,
+  onFocusSearchBar,
+  handleSearchKeyChange,
+  setExpand,
+  toggleNodeExpansion,
+  focusNode,
+  onNodeClick,
+  updateVisibleNodes,
+  mountExpandingIndicator,
+}
diff --git a/yarn.lock b/yarn.lock
index 37ef08f..64969bb 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -762,6 +762,11 @@
   resolved "https://registry.yarnpkg.com/@types/filewriter/-/filewriter-0.0.28.tgz#c054e8af4d9dd75db4e63abc76f885168714d4b3"
   integrity sha1-wFTor02d11205jq8dviFFocU1LM=
 
+"@types/ini@^1.3.30":
+  version "1.3.30"
+  resolved "https://registry.yarnpkg.com/@types/ini/-/ini-1.3.30.tgz#d1485459c9fad84e937414b832a2adb649eab379"
+  integrity sha512-2+iF8zPSbpU83UKE+PNd4r/MhwNAdyGpk3H+VMgEH3EhjFZq1kouLgRoZrmIcmoGX97xFvqdS44DkICR5Nz3tQ==
+
 "@types/nprogress@^0.0.29":
   version "0.0.29"
   resolved "https://registry.yarnpkg.com/@types/nprogress/-/nprogress-0.0.29.tgz#060bd510022a005f1840234030d3132fb9195471"