diff --git a/src/background/index.js b/src/background/index.js
index 040a2d5..e968c82 100644
--- a/src/background/index.js
+++ b/src/background/index.js
@@ -1,36 +1,22 @@
-import * as keys from './keys';
-import * as inputActions from '../actions/input';
-import * as operationActions from '../actions/operation';
-import * as commandActions from '../actions/command';
 import * as consoleActions from '../actions/console';
 import * as settingsActions from '../actions/setting';
-import * as tabActions from '../actions/tab';
+import BackgroundComponent from '../components/background';
+import BackgroundInputComponent from '../components/background-input';
 import reducers from '../reducers';
 import messages from '../content/messages';
 import * as store from '../store';
 
-let prevInput = [];
-let settings = {};
-
 const backgroundStore = store.createStore(reducers, (e, sender) => {
   console.error('Vim-Vixen:', e);
   if (sender) {
     backgroundStore.dispatch(consoleActions.showError(e.message), sender);
   }
 });
+const backgroundComponent = new BackgroundComponent(backgroundStore);
+const backgroundInputComponent = new BackgroundInputComponent(backgroundStore);
 backgroundStore.subscribe((sender) => {
-  let currentInput = backgroundStore.getState().input;
-  if (JSON.stringify(prevInput) === JSON.stringify(currentInput)) {
-    return;
-  }
-  prevInput = currentInput;
-
-  if (currentInput.keys.length === 0) {
-    return;
-  }
-  if (sender) {
-    return keyQueueChanged(backgroundStore.getState(), sender);
-  }
+  backgroundComponent.update(sender);
+  backgroundInputComponent.update(sender);
 });
 backgroundStore.subscribe((sender) => {
   if (sender) {
@@ -40,68 +26,5 @@ backgroundStore.subscribe((sender) => {
     });
   }
 });
-backgroundStore.subscribe(() => {
-  let state = backgroundStore.getState().setting;
-  if (!state.settings.json) {
-    return;
-  }
-  settings = JSON.parse(backgroundStore.getState().setting.settings.json);
-});
-
-const keyQueueChanged = (state, sender) => {
-  let prefix = keys.asKeymapChars(state.input.keys);
-  let matched = Object.keys(settings.keymaps).filter((keyStr) => {
-    return keyStr.startsWith(prefix);
-  });
-  if (matched.length === 0) {
-    backgroundStore.dispatch(inputActions.clearKeys(), sender);
-    return Promise.resolve();
-  } else if (matched.length > 1 ||
-    matched.length === 1 && prefix !== matched[0]) {
-    return Promise.resolve();
-  }
-  let action = settings.keymaps[matched];
-  backgroundStore.dispatch(
-    operationActions.exec(action, sender.tab, settings), sender);
-  backgroundStore.dispatch(inputActions.clearKeys(), sender);
-};
-
-const handleMessage = (message, sender) => {
-  switch (message.type) {
-  case messages.KEYDOWN:
-    return backgroundStore.dispatch(
-      inputActions.keyPress(message.code, message.ctrl), sender);
-  case messages.OPEN_URL:
-    if (message.newTab) {
-      return backgroundStore.dispatch(
-        tabActions.openNewTab(message.url), sender);
-    }
-    return backgroundStore.dispatch(
-      tabActions.openToTab(message.url, sender.tab), sender);
-  case messages.CONSOLE_BLURRED:
-    return backgroundStore.dispatch(
-      consoleActions.hide(), sender);
-  case messages.CONSOLE_ENTERED:
-    return backgroundStore.dispatch(
-      commandActions.exec(message.text, settings), sender);
-  case messages.CONSOLE_CHANGEED:
-    return backgroundStore.dispatch(
-      commandActions.complete(message.text, settings), sender);
-  case messages.SETTINGS_RELOAD:
-    backgroundStore.dispatch(settingsActions.load());
-  }
-};
-
-browser.runtime.onMessage.addListener((message, sender) => {
-  try {
-    handleMessage(message, sender);
-  } catch (e) {
-    backgroundStore.dispatch(consoleActions.showError(e.message), sender);
-  }
-});
-
-const initializeSettings = () => {
-  backgroundStore.dispatch(settingsActions.load());
-};
 
-initializeSettings();
+backgroundStore.dispatch(settingsActions.load());
diff --git a/src/components/background-input.js b/src/components/background-input.js
new file mode 100644
index 0000000..9c6ef1c
--- /dev/null
+++ b/src/components/background-input.js
@@ -0,0 +1,55 @@
+import * as inputActions from '../actions/input';
+import * as keys from '../shared/keys';
+import * as operationActions from '../actions/operation';
+
+export default class BackgroundInputComponent {
+  constructor(store) {
+    this.store = store;
+    this.keymaps = {};
+    this.prevInputs = [];
+  }
+
+  update(sender) {
+    let state = this.store.getState();
+    this.reloadSettings(state.setting);
+    this.handleKeyInputs(sender, state.input);
+  }
+
+  reloadSettings(setting) {
+    if (!setting.settings.json) {
+      return;
+    }
+    this.keymaps = JSON.parse(setting.settings.json).keymaps;
+  }
+
+  handleKeyInputs(sender, input) {
+    if (JSON.stringify(this.prevInputs) === JSON.stringify(input)) {
+      return;
+    }
+    this.prevInputs = input;
+
+    if (input.keys.length === 0) {
+      return;
+    }
+    if (sender) {
+      return this.handleKeysChanged(sender, input);
+    }
+  }
+
+  handleKeysChanged(sender, input) {
+    let prefix = keys.asKeymapChars(input.keys);
+    let matched = Object.keys(this.keymaps).filter((keyStr) => {
+      return keyStr.startsWith(prefix);
+    });
+    if (matched.length === 0) {
+      this.store.dispatch(inputActions.clearKeys(), sender);
+      return Promise.resolve();
+    } else if (matched.length > 1 ||
+      matched.length === 1 && prefix !== matched[0]) {
+      return Promise.resolve();
+    }
+    let operation = this.keymaps[matched];
+    this.store.dispatch(operationActions.exec(operation, sender.tab), sender);
+    this.store.dispatch(inputActions.clearKeys(), sender);
+  }
+}
diff --git a/src/components/background.js b/src/components/background.js
new file mode 100644
index 0000000..4c5bb19
--- /dev/null
+++ b/src/components/background.js
@@ -0,0 +1,59 @@
+import messages from '../content/messages';
+import * as commandActions from '../actions/command';
+import * as consoleActions from '../actions/console';
+import * as inputActions from '../actions/input';
+import * as settingsActions from '../actions/setting';
+import * as tabActions from '../actions/tab';
+
+export default class BackgroundComponent {
+  constructor(store) {
+    this.store = store;
+    this.setting = {};
+
+    browser.runtime.onMessage.addListener((message, sender) => {
+      try {
+        this.onMessage(message, sender);
+      } catch (e) {
+        this.store.dispatch(consoleActions.showError(e.message), sender);
+      }
+    });
+  }
+
+  update() {
+    let state = this.store.getState();
+    this.updateSettings(state.setting);
+  }
+
+  updateSettings(setting) {
+    if (!setting.settings.json) {
+      return;
+    }
+    this.settings = JSON.parse(setting.settings.json);
+  }
+
+  onMessage(message, sender) {
+    switch (message.type) {
+    case messages.KEYDOWN:
+      return this.store.dispatch(
+        inputActions.keyPress(message.code, message.ctrl), sender);
+    case messages.OPEN_URL:
+      if (message.newTab) {
+        return this.store.dispatch(
+          tabActions.openNewTab(message.url), sender);
+      }
+      return this.store.dispatch(
+        tabActions.openToTab(message.url, sender.tab), sender);
+    case messages.CONSOLE_BLURRED:
+      return this.store.dispatch(
+        consoleActions.hide(), sender);
+    case messages.CONSOLE_ENTERED:
+      return this.store.dispatch(
+        commandActions.exec(message.text, this.settings), sender);
+    case messages.CONSOLE_CHANGEED:
+      return this.store.dispatch(
+        commandActions.complete(message.text, this.settings), sender);
+    case messages.SETTINGS_RELOAD:
+      this.store.dispatch(settingsActions.load());
+    }
+  }
+}
diff --git a/src/background/keys.js b/src/shared/keys.js
similarity index 100%
rename from src/background/keys.js
rename to src/shared/keys.js
diff --git a/test/background/keys.test.js b/test/shared/keys.test.js
similarity index 92%
rename from test/background/keys.test.js
rename to test/shared/keys.test.js
index 2cb9a3a..53c953d 100644
--- a/test/background/keys.test.js
+++ b/test/shared/keys.test.js
@@ -1,5 +1,5 @@
 import { expect } from "chai";
-import * as keys from '../../src/background/keys';
+import * as keys from '../../src/shared/keys';
 
 describe("keys", () => {
   const KEYMAP = {