diff --git a/.gitmodules b/.gitmodules
new file mode 100644
index 0000000000000000000000000000000000000000..1edad4b653470d853ca94ae187fea53d2eb37494
--- /dev/null
+++ b/.gitmodules
@@ -0,0 +1,3 @@
+[submodule "src/backend/public/algorithms"]
+	path = src/backend/public/algorithms
+	url = git@github.com:algorithm-visualizer/algorithms.git
diff --git a/environment.js b/environment.js
index c9c9819cef88df30696cf1a91a876bb1fc629916..fc365b163a2b434153c27125b7deb8c06f9d14e5 100644
--- a/environment.js
+++ b/environment.js
@@ -8,6 +8,10 @@ const {
 
   GITHUB_CLIENT_ID,
   GITHUB_CLIENT_SECRET,
+  GITHUB_BOT_USERNAME,
+  GITHUB_BOT_PASSWORD,
+  GITHUB_ORG = 'algorithm-visualizer',
+  GITHUB_REPO_ALGORITHMS = 'algorithms',
 } = process.env;
 
 const __PROD__ = NODE_ENV === 'production';
@@ -18,6 +22,14 @@ const proxyPort = parseInt(PROXY_PORT);
 
 const githubClientId = GITHUB_CLIENT_ID;
 const githubClientSecret = GITHUB_CLIENT_SECRET;
+const githubBotAuth = {
+  username: GITHUB_BOT_USERNAME,
+  password: GITHUB_BOT_PASSWORD,
+};
+const githubOrg = GITHUB_ORG;
+const githubRepos = {
+  algorithms: GITHUB_REPO_ALGORITHMS
+};
 
 const builtPath = path.resolve(__dirname, 'built');
 const frontendBuiltPath = path.resolve(builtPath, 'frontend');
@@ -36,6 +48,9 @@ module.exports = {
   proxyPort,
   githubClientId,
   githubClientSecret,
+  githubBotAuth,
+  githubOrg,
+  githubRepos,
   frontendBuiltPath,
   backendBuiltPath,
   frontendSrcPath,
diff --git a/src/backend/controllers/auth.js b/src/backend/controllers/auth.js
index e3d43f3407edcfb2460333cb1f215846aeec6cbe..6855ae429f8b844af4fca0834a6952573cb0eb36 100644
--- a/src/backend/controllers/auth.js
+++ b/src/backend/controllers/auth.js
@@ -21,7 +21,7 @@ const response = (req, res, next) => {
     const { access_token } = response.data;
     res.cookie('access_token', access_token);
     res.redirect('/');
-  });
+  }).catch(next);
 };
 
 const destroy = (req, res, next) => {
diff --git a/src/backend/controllers/directory.js b/src/backend/controllers/hierarchy.js
similarity index 73%
rename from src/backend/controllers/directory.js
rename to src/backend/controllers/hierarchy.js
index be4ed502672ec628aa7017d8717326b55c2fa2fb..f68883e812f22105801dead939d28934756b01a6 100644
--- a/src/backend/controllers/directory.js
+++ b/src/backend/controllers/hierarchy.js
@@ -5,11 +5,11 @@ import { NotFoundError } from '/common/error';
 
 const router = express.Router();
 
-const getPath = (...args) => path.resolve(__dirname, '..', '..', '..', 'algorithm', ...args);
+const getPath = (...args) => path.resolve(__dirname, '..', 'public', 'algorithms', ...args);
+const createKey = name => name.toLowerCase().replace(/ /g, '-');
+const list = dirPath => fs.readdirSync(dirPath).filter(filename => !filename.startsWith('.'));
 
-const readCategories = () => {
-  const createKey = name => name.toLowerCase().replace(/ /g, '-');
-  const list = dirPath => fs.readdirSync(dirPath).filter(filename => !filename.startsWith('.'));
+const cacheHierarchy = () => {
   const getCategory = categoryName => {
     const categoryKey = createKey(categoryName);
     const categoryPath = getPath(categoryName);
@@ -33,16 +33,16 @@ const readCategories = () => {
   return list(getPath()).map(getCategory);
 };
 
-const categories = readCategories();
+const hierarchy = cacheHierarchy();
 
-const getCategories = (req, res, next) => {
-  res.json({ categories });
+const getHierarchy = (req, res, next) => {
+  res.json({ hierarchy });
 };
 
 const getFile = (req, res, next) => {
   const { categoryKey, algorithmKey, fileName } = req.params;
 
-  const category = categories.find(category => category.key === categoryKey);
+  const category = hierarchy.find(category => category.key === categoryKey);
   if (!category) return next(new NotFoundError());
   const algorithm = category.algorithms.find(algorithm => algorithm.key === algorithmKey);
   if (!algorithm) return next(new NotFoundError());
@@ -53,7 +53,7 @@ const getFile = (req, res, next) => {
 };
 
 router.route('/')
-  .get(getCategories);
+  .get(getHierarchy);
 
 router.route('/:categoryKey/:algorithmKey/:fileName')
   .get(getFile);
diff --git a/src/backend/controllers/index.js b/src/backend/controllers/index.js
index 9c9e1a1a33a9bf4d1080ba0d512cc2f3c60b1cb2..3f9484e72cae0d997be393b0410dc3ac0b0fd2c7 100644
--- a/src/backend/controllers/index.js
+++ b/src/backend/controllers/index.js
@@ -1,13 +1,13 @@
 import express from 'express';
 import { AuthorizationError, NotFoundError, PermissionError } from '/common/error';
 import auth from './auth';
-import directory from './directory';
+import hierarchy from './hierarchy';
 import wiki from './wiki';
 
 const router = new express.Router();
 
 router.use('/auth', auth);
-router.use('/directory', directory);
+router.use('/hierarchy', hierarchy);
 router.use('/wiki', wiki);
 router.use((req, res, next) => next(new NotFoundError()));
 router.use((err, req, res, next) => {
diff --git a/src/backend/public/algorithms b/src/backend/public/algorithms
new file mode 160000
index 0000000000000000000000000000000000000000..417e8c9ffe9bf8411f0099ea01098c0919468a07
--- /dev/null
+++ b/src/backend/public/algorithms
@@ -0,0 +1 @@
+Subproject commit 417e8c9ffe9bf8411f0099ea01098c0919468a07
diff --git a/src/frontend/apis/index.js b/src/frontend/apis/index.js
index f0c333cb0b5e207f61a180778b6cd7adf72684ef..7a3d67b54b69e3d4de760ef2c8d0a6a44be9b2ff 100644
--- a/src/frontend/apis/index.js
+++ b/src/frontend/apis/index.js
@@ -2,7 +2,7 @@ import Promise from 'bluebird';
 import axios from 'axios';
 import GitHub from 'github-api';
 
-let gitHub = new GitHub();
+let gh = new GitHub();
 
 axios.interceptors.response.use(response => {
   return response.data;
@@ -49,9 +49,9 @@ const PUT = URL => {
   });
 };
 
-const DirectoryApi = {
-  getCategories: GET('/directory'),
-  getFile: GET('/directory/:categoryKey/:algorithmKey/:fileName'),
+const HierarchyApi = {
+  getHierarchy: GET('/hierarchy'),
+  getFile: GET('/hierarchy/:categoryKey/:algorithmKey/:fileName'),
 };
 
 const WikiApi = {
@@ -60,12 +60,12 @@ const WikiApi = {
 };
 
 const GitHubApi = {
-  auth: token => gitHub = new GitHub({ token }),
-  getProfile: () => gitHub.getUser().getProfile(),
+  auth: token => gh = new GitHub({ token }),
+  getProfile: () => gh.getUser().getProfile(),
 };
 
 export {
-  DirectoryApi,
+  HierarchyApi,
   WikiApi,
   GitHubApi,
 };
\ No newline at end of file
diff --git a/src/frontend/components/App/index.jsx b/src/frontend/components/App/index.jsx
index 5c9b2c557d0db9181a3e5470021f2938b0b35f29..493f6d8cc38dd36c1568a6e1124a7f7d804e3b71 100644
--- a/src/frontend/components/App/index.jsx
+++ b/src/frontend/components/App/index.jsx
@@ -6,7 +6,7 @@ import { Workspace, WSSectionContainer, WSTabContainer } from '/workspace/compon
 import { Section } from '/workspace/core';
 import { actions as toastActions } from '/reducers/toast';
 import { actions as envActions } from '/reducers/env';
-import { DirectoryApi, GitHubApi } from '/apis';
+import { HierarchyApi, GitHubApi } from '/apis';
 import { tracerManager } from '/core';
 import styles from './stylesheet.scss';
 import 'axios-progress-bar/dist/nprogress.css'
@@ -33,11 +33,11 @@ class App extends React.Component {
   componentDidMount() {
     this.updateDirectory(this.props.match.params);
 
-    DirectoryApi.getCategories()
-      .then(({ categories }) => {
-        this.props.setCategories(categories);
+    HierarchyApi.getHierarchy()
+      .then(({ hierarchy }) => {
+        this.props.setHierarchy(hierarchy);
         const { categoryKey, algorithmKey } = this.props.env;
-        const category = categories.find(category => category.key === categoryKey) || categories[0];
+        const category = hierarchy.find(category => category.key === categoryKey) || hierarchy[0];
         const algorithm = category.algorithms.find(algorithm => algorithm.key === algorithmKey) || category.algorithms[0];
         this.props.history.push(`/${category.key}/${algorithm.key}`);
       });
@@ -63,7 +63,7 @@ class App extends React.Component {
   updateDirectory({ categoryKey = null, algorithmKey = null }) {
     if (categoryKey && algorithmKey) {
       this.props.setDirectory(categoryKey, algorithmKey);
-      DirectoryApi.getFile(categoryKey, algorithmKey, 'code.js').then(code => tracerManager.setCode(code));
+      HierarchyApi.getFile(categoryKey, algorithmKey, 'code.js').then(code => tracerManager.setCode(code));
     }
   }
 
@@ -88,11 +88,11 @@ class App extends React.Component {
   }
 
   render() {
-    const { categories, categoryKey, algorithmKey } = this.props.env;
+    const { hierarchy, categoryKey, algorithmKey } = this.props.env;
 
     const navigatorOpened = true;
 
-    return categories && categoryKey && algorithmKey && (
+    return hierarchy && categoryKey && algorithmKey && (
       <div className={styles.app}>
         <Workspace className={styles.workspace} wsProps={{ horizontal: false }}>
           <Header wsProps={{
diff --git a/src/frontend/components/DescriptionViewer/index.jsx b/src/frontend/components/DescriptionViewer/index.jsx
index 22d030bb961d15d1d4ee67b65112f07af76e29c8..1b97c46f510b9965dd20ff22f038a346dd38f2e2 100644
--- a/src/frontend/components/DescriptionViewer/index.jsx
+++ b/src/frontend/components/DescriptionViewer/index.jsx
@@ -1,7 +1,7 @@
 import React from 'react';
 import { connect } from 'react-redux';
 import { actions as envActions } from '/reducers/env';
-import { DirectoryApi } from '/apis/index';
+import { HierarchyApi } from '/apis/index';
 import { MarkdownViewer } from '/components';
 
 @connect(
@@ -37,7 +37,7 @@ class DescriptionViewer extends React.Component {
 
   loadMarkdown(href) {
     const [, , categoryKey, algorithmKey] = href.split('/');
-    DirectoryApi.getFile(categoryKey, algorithmKey, 'desc.md')
+    HierarchyApi.getFile(categoryKey, algorithmKey, 'desc.md')
       .then(source => this.setState({ source }))
       .catch(() => this.setState({ source: null }));
   }
diff --git a/src/frontend/components/Header/index.jsx b/src/frontend/components/Header/index.jsx
index b7680c4b695ff328f6ca04ebfec52ec4dc94fbb3..93ee1c5f41646f3efe2885bb00b1b6fad748663e 100644
--- a/src/frontend/components/Header/index.jsx
+++ b/src/frontend/components/Header/index.jsx
@@ -70,9 +70,9 @@ class Header extends React.Component {
   render() {
     const { interval, paused, started, profile } = this.state;
     const { className, onClickTitleBar, navigatorOpened } = this.props;
-    const { categories, categoryKey, algorithmKey, signedIn } = this.props.env;
+    const { hierarchy, categoryKey, algorithmKey, signedIn } = this.props.env;
 
-    const category = categories.find(category => category.key === categoryKey);
+    const category = hierarchy.find(category => category.key === categoryKey);
     const algorithm = category.algorithms.find(algorithm => algorithm.key === algorithmKey);
 
     return (
diff --git a/src/frontend/components/Navigator/index.jsx b/src/frontend/components/Navigator/index.jsx
index 37d03dd98739ca03f2eab5b71f7c7fe7a9465235..d03fdd4956208fba16a69accd1793d39ef24a1d6 100644
--- a/src/frontend/components/Navigator/index.jsx
+++ b/src/frontend/components/Navigator/index.jsx
@@ -40,10 +40,10 @@ class Navigator extends React.Component {
   }
 
   handleChangeQuery(e) {
-    const { categories } = this.props.env;
+    const { hierarchy } = this.props.env;
     const categoriesOpened = {};
     const query = e.target.value;
-    categories.forEach(category => {
+    hierarchy.forEach(category => {
       if (this.testQuery(name) || category.algorithms.find(algorithm => this.testQuery(algorithm.name))) {
         categoriesOpened[category.key] = true;
       }
@@ -60,7 +60,7 @@ class Navigator extends React.Component {
   render() {
     const { categoriesOpened, query } = this.state;
     const { className, style } = this.props;
-    const { categoryKey: selectedCategoryKey, algorithmKey: selectedAlgorithmKey, categories } = this.props.env;
+    const { hierarchy, categoryKey: selectedCategoryKey, algorithmKey: selectedAlgorithmKey } = this.props.env;
 
     return (
       <nav className={classes(styles.navigator, className)} style={style}>
@@ -71,7 +71,7 @@ class Navigator extends React.Component {
         </div>
         <div className={styles.algorithm_list}>
           {
-            categories.map(category => {
+            hierarchy.map(category => {
               const categoryOpened = categoriesOpened[category.key];
               let algorithms = category.algorithms;
               if (!this.testQuery(category.name)) {
diff --git a/src/frontend/reducers/env.js b/src/frontend/reducers/env.js
index b875a11245669df4e946db58716ab63851ccf58d..d6dbb0c758b5bd315c43d07e2f6046ff96e252ab 100644
--- a/src/frontend/reducers/env.js
+++ b/src/frontend/reducers/env.js
@@ -3,20 +3,20 @@ import { combineActions, createAction, handleActions } from 'redux-actions';
 
 const prefix = 'ENV';
 
-const setCategories = createAction(`${prefix}/SET_CATEGORIES`, categories => ({ categories }));
+const setHierarchy = createAction(`${prefix}/SET_HIERARCHY`, hierarchy => ({ hierarchy }));
 const setDirectory = createAction(`${prefix}/SET_DIRECTORY`, (categoryKey, algorithmKey) => ({
   categoryKey,
   algorithmKey,
 }));
 
 export const actions = {
-  setCategories,
+  setHierarchy,
   setDirectory,
 };
 
 const accessToken = Cookies.get('access_token');
 const defaultState = {
-  categories: null,
+  hierarchy: null,
   categoryKey: null,
   algorithmKey: null,
   accessToken,
@@ -25,7 +25,7 @@ const defaultState = {
 
 export default handleActions({
   [combineActions(
-    setCategories,
+    setHierarchy,
     setDirectory,
   )]: (state, { payload }) => ({
     ...state,