diff --git a/.DS_Store b/.DS_Store
deleted file mode 100644
index 5eaa47a..0000000
Binary files a/.DS_Store and /dev/null differ
diff --git a/.env b/.env
new file mode 100644
index 0000000..fff8dc8
--- /dev/null
+++ b/.env
@@ -0,0 +1,2 @@
+HTTP_PORT = 8080
+HTTPS_PORT = 8443
diff --git a/.env.development b/.env.development
new file mode 100644
index 0000000..e502fc9
--- /dev/null
+++ b/.env.development
@@ -0,0 +1,2 @@
+CREDENTIALS_ENABLED = 0
+WEBHOOK_ENABLED = 0
diff --git a/.env.production b/.env.production
new file mode 100644
index 0000000..8cabc5a
--- /dev/null
+++ b/.env.production
@@ -0,0 +1,2 @@
+CREDENTIALS_ENABLED = 1
+WEBHOOK_ENABLED = 1
diff --git a/.gitignore b/.gitignore
index 689bc6a..ed81866 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,16 @@
+# WebStorm settings
 /.idea
+
+# npm
 /node_modules
 /npm-debug.log
-/public
-/pm2.config.js
+
+# macOS
 .DS_Store
+
+# local .env* files
+.env.local
+.env.*.local
+
+# downloaded files
+/public
diff --git a/.idea/encodings.xml b/.idea/encodings.xml
deleted file mode 100644
index 15a15b2..0000000
--- a/.idea/encodings.xml
+++ /dev/null
@@ -1,4 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="Encoding" addBOMForNewFiles="with NO BOM" />
-</project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
deleted file mode 100644
index 28a804d..0000000
--- a/.idea/misc.xml
+++ /dev/null
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="JavaScriptSettings">
-    <option name="languageLevel" value="ES6" />
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/modules.xml b/.idea/modules.xml
deleted file mode 100644
index fbd90b4..0000000
--- a/.idea/modules.xml
+++ /dev/null
@@ -1,8 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="ProjectModuleManager">
-    <modules>
-      <module fileurl="file://$PROJECT_DIR$/.idea/server.iml" filepath="$PROJECT_DIR$/.idea/server.iml" />
-    </modules>
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/server.iml b/.idea/server.iml
deleted file mode 100644
index 24643cc..0000000
--- a/.idea/server.iml
+++ /dev/null
@@ -1,12 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<module type="WEB_MODULE" version="4">
-  <component name="NewModuleRootManager">
-    <content url="file://$MODULE_DIR$">
-      <excludeFolder url="file://$MODULE_DIR$/.tmp" />
-      <excludeFolder url="file://$MODULE_DIR$/temp" />
-      <excludeFolder url="file://$MODULE_DIR$/tmp" />
-    </content>
-    <orderEntry type="inheritedJdk" />
-    <orderEntry type="sourceFolder" forTests="false" />
-  </component>
-</module>
\ No newline at end of file
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
deleted file mode 100644
index d6eacee..0000000
--- a/.idea/vcs.xml
+++ /dev/null
@@ -1,8 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$" vcs="Git" />
-    <mapping directory="$PROJECT_DIR$/public/algorithms" vcs="Git" />
-    <mapping directory="$PROJECT_DIR$/src/public/algorithms" vcs="Git" />
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/webResources.xml b/.idea/webResources.xml
deleted file mode 100644
index edf30b3..0000000
--- a/.idea/webResources.xml
+++ /dev/null
@@ -1,14 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="WebResourcesPaths">
-    <contentEntries>
-      <entry url="file://$PROJECT_DIR$">
-        <entryData>
-          <resourceRoots>
-            <path value="file://$PROJECT_DIR$/src" />
-          </resourceRoots>
-        </entryData>
-      </entry>
-    </contentEntries>
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
deleted file mode 100644
index 3b2c9de..0000000
--- a/.idea/workspace.xml
+++ /dev/null
@@ -1,266 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="ChangeListManager">
-    <list default="true" id="33967b4c-80ab-44ef-aea7-fe45cd91b9b7" name="Default Changelist" comment="">
-      <change afterPath="$PROJECT_DIR$/.gitignore" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/.idea/encodings.xml" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/.idea/misc.xml" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/.idea/modules.xml" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/.idea/server.iml" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/.idea/vcs.xml" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/.idea/webResources.xml" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/app/backend.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/app/frontend.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/app/index.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/bin/pull" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/bin/www" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/package.json" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/pm2.config.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/public/algorithm-visualizer.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/public/codes/3fe76da7-b5cb-4925-8b32-9ff05204e78d/Main" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/public/codes/3fe76da7-b5cb-4925-8b32-9ff05204e78d/Main.cpp" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/apis/index.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/common/config.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/common/error.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/common/hierarchy.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/common/util.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/common/webhook.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/controllers/algorithms.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/controllers/auth.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/controllers/index.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/controllers/tracers.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/controllers/visualizations.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/index.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/models/Algorithm.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/models/Category.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/models/File.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/models/Hierarchy.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/models/index.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/tracers/ImageBuilder.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/tracers/WorkerBuilder.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/tracers/cpp/Dockerfile" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/tracers/index.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/tracers/java/Dockerfile" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/src/tracers/js/worker.js" afterDir="false" />
-      <change afterPath="$PROJECT_DIR$/webpack.backend.config.js" afterDir="false" />
-    </list>
-    <ignored path="$PROJECT_DIR$/.tmp/" />
-    <ignored path="$PROJECT_DIR$/temp/" />
-    <ignored path="$PROJECT_DIR$/tmp/" />
-    <option name="EXCLUDED_CONVERTED_TO_IGNORED" value="true" />
-    <option name="SHOW_DIALOG" value="false" />
-    <option name="HIGHLIGHT_CONFLICTS" value="true" />
-    <option name="HIGHLIGHT_NON_ACTIVE_CHANGELIST" value="false" />
-    <option name="LAST_RESOLUTION" value="IGNORE" />
-  </component>
-  <component name="FileEditorManager">
-    <leaf>
-      <file pinned="false" current-in-tab="true">
-        <entry file="file://$PROJECT_DIR$/bin/pull">
-          <provider selected="true" editor-type-id="text-editor">
-            <state relative-caret-position="105">
-              <caret line="7" lean-forward="true" selection-start-line="7" selection-end-line="7" />
-            </state>
-          </provider>
-        </entry>
-      </file>
-    </leaf>
-  </component>
-  <component name="FindInProjectRecents">
-    <findStrings>
-      <find>robot</find>
-    </findStrings>
-    <dirStrings>
-      <dir>$PROJECT_DIR$</dir>
-    </dirStrings>
-  </component>
-  <component name="Git.Settings">
-    <option name="RECENT_GIT_ROOT_PATH" value="$PROJECT_DIR$" />
-  </component>
-  <component name="IdeDocumentHistory">
-    <option name="CHANGED_PATHS">
-      <list>
-        <option value="$PROJECT_DIR$/package.json" />
-        <option value="$PROJECT_DIR$/.gitignore" />
-        <option value="$PROJECT_DIR$/bin/pull" />
-      </list>
-    </option>
-  </component>
-  <component name="ProjectFrameBounds" extendedState="6" fullScreen="true">
-    <option name="width" value="1680" />
-    <option name="height" value="1050" />
-  </component>
-  <component name="ProjectLevelVcsManager" settingsEditedManually="true" />
-  <component name="ProjectView">
-    <navigator proportions="" version="1">
-      <foldersAlwaysOnTop value="true" />
-    </navigator>
-    <panes>
-      <pane id="ProjectPane">
-        <subPane>
-          <expand>
-            <path>
-              <item name="server" type="b2602c69:ProjectViewProjectNode" />
-              <item name="server" type="462c0819:PsiDirectoryNode" />
-            </path>
-            <path>
-              <item name="server" type="b2602c69:ProjectViewProjectNode" />
-              <item name="server" type="462c0819:PsiDirectoryNode" />
-              <item name="app" type="462c0819:PsiDirectoryNode" />
-            </path>
-            <path>
-              <item name="server" type="b2602c69:ProjectViewProjectNode" />
-              <item name="server" type="462c0819:PsiDirectoryNode" />
-              <item name="bin" type="462c0819:PsiDirectoryNode" />
-            </path>
-            <path>
-              <item name="server" type="b2602c69:ProjectViewProjectNode" />
-              <item name="server" type="462c0819:PsiDirectoryNode" />
-              <item name="src" type="462c0819:PsiDirectoryNode" />
-            </path>
-            <path>
-              <item name="server" type="b2602c69:ProjectViewProjectNode" />
-              <item name="server" type="462c0819:PsiDirectoryNode" />
-              <item name="src" type="462c0819:PsiDirectoryNode" />
-              <item name="controllers" type="462c0819:PsiDirectoryNode" />
-            </path>
-          </expand>
-          <select />
-        </subPane>
-      </pane>
-      <pane id="Scope" />
-    </panes>
-  </component>
-  <component name="PropertiesComponent">
-    <property name="WebServerToolWindowFactoryState" value="false" />
-    <property name="last_opened_file_path" value="$PROJECT_DIR$" />
-    <property name="nodejs_interpreter_path.stuck_in_default_project" value="undefined stuck path" />
-    <property name="nodejs_npm_path_reset_for_default_project" value="true" />
-    <property name="nodejs_package_manager_path" value="npm" />
-  </component>
-  <component name="RecentsManager">
-    <key name="MoveFile.RECENT_KEYS">
-      <recent name="$PROJECT_DIR$" />
-    </key>
-    <key name="CopyFile.RECENT_KEYS">
-      <recent name="$PROJECT_DIR$" />
-    </key>
-  </component>
-  <component name="RunDashboard">
-    <option name="ruleStates">
-      <list>
-        <RuleState>
-          <option name="name" value="ConfigurationTypeDashboardGroupingRule" />
-        </RuleState>
-        <RuleState>
-          <option name="name" value="StatusDashboardGroupingRule" />
-        </RuleState>
-      </list>
-    </option>
-  </component>
-  <component name="SvnConfiguration">
-    <configuration />
-  </component>
-  <component name="TaskManager">
-    <task active="true" id="Default" summary="Default task">
-      <changelist id="33967b4c-80ab-44ef-aea7-fe45cd91b9b7" name="Default Changelist" comment="" />
-      <created>1559885518055</created>
-      <option name="number" value="Default" />
-      <option name="presentableId" value="Default" />
-      <updated>1559885518055</updated>
-      <workItem from="1559885519397" duration="1598000" />
-    </task>
-    <servers />
-  </component>
-  <component name="TimeTrackingManager">
-    <option name="totallyTimeSpent" value="1598000" />
-  </component>
-  <component name="ToolWindowManager">
-    <frame x="0" y="0" width="1680" height="1050" extended-state="6" />
-    <editor active="true" />
-    <layout>
-      <window_info id="Favorites" side_tool="true" />
-      <window_info active="true" content_ui="combo" id="Project" order="0" visible="true" weight="0.24954791" />
-      <window_info id="Structure" order="1" side_tool="true" weight="0.25" />
-      <window_info anchor="bottom" id="Docker" show_stripe_button="false" />
-      <window_info anchor="bottom" id="Version Control" />
-      <window_info anchor="bottom" id="Terminal" visible="true" weight="0.32959184" />
-      <window_info anchor="bottom" id="Event Log" side_tool="true" />
-      <window_info anchor="bottom" id="Message" order="0" />
-      <window_info anchor="bottom" id="Find" order="1" />
-      <window_info anchor="bottom" id="Run" order="2" />
-      <window_info anchor="bottom" id="Debug" order="3" weight="0.4" />
-      <window_info anchor="bottom" id="Cvs" order="4" weight="0.25" />
-      <window_info anchor="bottom" id="Inspection" order="5" weight="0.4" />
-      <window_info anchor="bottom" id="TODO" order="6" />
-      <window_info anchor="right" id="Commander" internal_type="SLIDING" order="0" type="SLIDING" weight="0.4" />
-      <window_info anchor="right" id="Ant Build" order="1" weight="0.25" />
-      <window_info anchor="right" content_ui="combo" id="Hierarchy" order="2" weight="0.25" />
-    </layout>
-  </component>
-  <component name="TypeScriptGeneratedFilesManager">
-    <option name="version" value="1" />
-  </component>
-  <component name="editorHistoryManager">
-    <entry file="file://$PROJECT_DIR$/package.json">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="75">
-          <caret line="5" column="56" selection-start-line="5" selection-start-column="56" selection-end-line="5" selection-end-column="56" />
-        </state>
-      </provider>
-    </entry>
-    <entry file="file://$PROJECT_DIR$/src/apis/index.js">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="30">
-          <caret line="2" column="20" lean-forward="true" selection-start-line="2" selection-start-column="20" selection-end-line="2" selection-end-column="20" />
-        </state>
-      </provider>
-    </entry>
-    <entry file="file://$PROJECT_DIR$/pm2.config.js">
-      <provider selected="true" editor-type-id="text-editor" />
-    </entry>
-    <entry file="file://$PROJECT_DIR$/webpack.backend.config.js">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="-47" />
-      </provider>
-    </entry>
-    <entry file="file://$PROJECT_DIR$/app/backend.js">
-      <provider selected="true" editor-type-id="text-editor" />
-    </entry>
-    <entry file="file://$PROJECT_DIR$/app/index.js">
-      <provider selected="true" editor-type-id="text-editor" />
-    </entry>
-    <entry file="file://$PROJECT_DIR$/src/controllers/index.js">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="60">
-          <caret line="4" lean-forward="true" selection-start-line="4" selection-end-line="4" />
-        </state>
-      </provider>
-    </entry>
-    <entry file="file://$PROJECT_DIR$/.gitignore">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="90">
-          <caret line="6" lean-forward="true" selection-start-line="6" selection-end-line="6" />
-        </state>
-      </provider>
-    </entry>
-    <entry file="file://$PROJECT_DIR$/src/index.js">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="285">
-          <caret line="19" column="13" selection-start-line="19" selection-start-column="13" selection-end-line="19" selection-end-column="13" />
-          <folding>
-            <element signature="e#0#30#0" expanded="true" />
-          </folding>
-        </state>
-      </provider>
-    </entry>
-    <entry file="file://$PROJECT_DIR$/bin/pull">
-      <provider selected="true" editor-type-id="text-editor">
-        <state relative-caret-position="105">
-          <caret line="7" lean-forward="true" selection-start-line="7" selection-end-line="7" />
-        </state>
-      </provider>
-    </entry>
-  </component>
-</project>
\ No newline at end of file
diff --git a/app/backend.js b/app/backend.js
deleted file mode 100644
index ebec15a..0000000
--- a/app/backend.js
+++ /dev/null
@@ -1,42 +0,0 @@
-const {
-  __DEV__,
-  backendBuildPath,
-} = require('../environment');
-
-if (__DEV__) {
-  const webpack = require('webpack');
-  const webpackConfig = require('../webpack.backend.config.js');
-  const compiler = webpack(webpackConfig);
-
-  let backend = null;
-  let lastHash = null;
-  compiler.watch({
-    watchOptions: {
-      ignored: /public/,
-    },
-  }, (err, stats) => {
-    if (err) {
-      lastHash = null;
-      compiler.purgeInputFileSystem();
-      console.error(err);
-    } else if (stats.hash !== lastHash) {
-      lastHash = stats.hash;
-      console.info(stats.toString({
-        cached: false,
-        colors: true,
-      }));
-
-      delete require.cache[require.resolve(backendBuildPath)];
-      backend = require(backendBuildPath).default;
-    }
-  });
-
-  const backendWrapper = (req, res, next) => backend(req, res, next);
-  backendWrapper.getHierarchy = () => backend.hierarchy;
-  module.exports = backendWrapper;
-} else {
-  const backend = require(backendBuildPath).default;
-  const backendWrapper = (req, res, next) => backend(req, res, next);
-  backendWrapper.getHierarchy = () => backend.hierarchy;
-  module.exports = backendWrapper;
-}
diff --git a/app/frontend.js b/app/frontend.js
deleted file mode 100644
index d54c3fb..0000000
--- a/app/frontend.js
+++ /dev/null
@@ -1,78 +0,0 @@
-const express = require('express');
-const path = require('path');
-const fs = require('fs');
-const url = require('url');
-const packageJson = require('../package');
-
-const {
-  __DEV__,
-  frontendSrcPath,
-  frontendBuildPath,
-} = require('../environment');
-
-const app = express();
-
-if (__DEV__) {
-  const webpack = require('webpack');
-  const webpackDev = require('webpack-dev-middleware');
-  const webpackHot = require('webpack-hot-middleware');
-  const webpackConfig = require('../webpack.frontend.config.js');
-  const compiler = webpack(webpackConfig);
-  app.use(express.static(path.resolve(frontendSrcPath, 'static')));
-  app.use(webpackDev(compiler, {
-    stats: {
-      cached: false,
-      colors: true,
-    },
-    serverSideRender: true,
-    index: false,
-  }));
-  app.use(webpackHot(compiler));
-  app.use((req, res, next) => {
-    const { fs } = res.locals;
-    const outputPath = res.locals.webpackStats.toJson().outputPath;
-    const filePath = path.resolve(outputPath, 'index.html');
-    fs.readFile(filePath, 'utf8', (err, data) => {
-      if (err) return next(err);
-      res.indexFile = data;
-      next();
-    });
-  });
-} else {
-  app.use(express.static(frontendBuildPath, { index: false }));
-  app.use((req, res, next) => {
-    const filePath = path.resolve(frontendBuildPath, 'index.html');
-    fs.readFile(filePath, 'utf8', (err, data) => {
-      if (err) return next(err);
-      res.indexFile = data;
-      next();
-    });
-  });
-}
-
-app.use((req, res) => {
-  const backend = require('./backend');
-  const hierarchy = backend.getHierarchy();
-
-  const [, categoryKey, algorithmKey] = url.parse(req.originalUrl).pathname.split('/');
-  let { title, description } = packageJson;
-  let algorithm = undefined;
-  if (categoryKey && categoryKey !== 'scratch-paper') {
-    algorithm = hierarchy.find(categoryKey, algorithmKey) || null;
-    if (algorithm) {
-      title = [algorithm.categoryName, algorithm.algorithmName].join(' - ');
-      description = algorithm.description;
-    } else {
-      res.status(404);
-    }
-  }
-
-  const indexFile = res.indexFile
-    .replace(/\$TITLE/g, title)
-    .replace(/\$DESCRIPTION/g, description)
-    .replace(/\$ALGORITHM/g, algorithm === undefined ? 'undefined' :
-      JSON.stringify(algorithm).replace(/</g, '\\u003c'));
-  res.send(indexFile);
-});
-
-module.exports = app;
diff --git a/app/index.js b/app/index.js
deleted file mode 100644
index 2cd4d10..0000000
--- a/app/index.js
+++ /dev/null
@@ -1,30 +0,0 @@
-const path = require('path');
-const express = require('express');
-const compression = require('compression');
-const app = express();
-
-const frontend = require('./frontend');
-const backend = require('./backend');
-
-const {
-  apiEndpoint,
-  credentials,
-} = require('../environment');
-
-app.use(compression());
-app.use((req, res, next) => {
-  if (req.hostname === 'algo-visualizer.jasonpark.me') {
-    res.redirect(301, 'https://algorithm-visualizer.org/');
-  } else if (credentials && !req.secure) {
-    res.redirect(301, `https://${req.hostname}${req.url}`);
-  } else {
-    next();
-  }
-});
-app.get('/robots.txt', (req, res) => {
-  res.sendFile(path.resolve(__dirname, '..', 'robots.txt'));
-});
-app.use(apiEndpoint, backend);
-app.use(frontend);
-
-module.exports = app;
diff --git a/bin/pull b/bin/pull
deleted file mode 100755
index e0acb4d..0000000
--- a/bin/pull
+++ /dev/null
@@ -1,7 +0,0 @@
-#!/usr/bin/env bash
-
-git fetch &&
-! git diff-index --quiet origin/master -- ':!package-lock.json' &&
-git reset --hard origin/master &&
-npm install &&
-npm run build
diff --git a/bin/www b/bin/www
deleted file mode 100755
index 19bd763..0000000
--- a/bin/www
+++ /dev/null
@@ -1,21 +0,0 @@
-#!/usr/bin/env node
-
-const http = require('http');
-const https = require('https');
-
-const app = require('../app');
-const {
-  httpPort,
-  httpsPort,
-  credentials,
-} = require('../environment');
-
-const httpServer = http.createServer(app);
-httpServer.listen(httpPort);
-console.info(`http: listening on port ${httpPort}`);
-
-if (credentials) {
-  const httpsServer = https.createServer(credentials, app);
-  httpsServer.listen(httpsPort);
-  console.info(`https: listening on port ${httpsPort}`);
-}
diff --git a/package-lock.json b/package-lock.json
new file mode 100644
index 0000000..c6f3005
--- /dev/null
+++ b/package-lock.json
@@ -0,0 +1,1640 @@
+{
+  "name": "@algorithm-visualizer/server",
+  "version": "2.0.0",
+  "lockfileVersion": 1,
+  "requires": true,
+  "dependencies": {
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+      "dev": true,
+      "requires": {
+        "@babel/highlight": "^7.0.0"
+      }
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+    "@babel/highlight": {
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+      "resolved": "https://registry.npmjs.org/@babel/highlight/-/highlight-7.0.0.tgz",
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+      "dev": true,
+      "requires": {
+        "chalk": "^2.0.0",
+        "esutils": "^2.0.2",
+        "js-tokens": "^4.0.0"
+      }
+    },
+    "@types/body-parser": {
+      "version": "1.17.0",
+      "resolved": "https://registry.npmjs.org/@types/body-parser/-/body-parser-1.17.0.tgz",
+      "integrity": "sha512-a2+YeUjPkztKJu5aIF2yArYFQQp8d51wZ7DavSHjFuY1mqVgidGyzEQ41JIVNy82fXj8yPgy2vJmfIywgESW6w==",
+      "dev": true,
+      "requires": {
+        "@types/connect": "*",
+        "@types/node": "*"
+      }
+    },
+    "@types/compression": {
+      "version": "0.0.36",
+      "resolved": "https://registry.npmjs.org/@types/compression/-/compression-0.0.36.tgz",
+      "integrity": "sha512-B66iZCIcD2eB2F8e8YDIVtCUKgfiseOR5YOIbmMN2tM57Wu55j1xSdxdSw78aVzsPmbZ6G+hINc+1xe1tt4NBg==",
+      "dev": true,
+      "requires": {
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+      }
+    },
+    "@types/connect": {
+      "version": "3.4.32",
+      "resolved": "https://registry.npmjs.org/@types/connect/-/connect-3.4.32.tgz",
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+      "dev": true,
+      "requires": {
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+    },
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+      "resolved": "https://registry.npmjs.org/@types/execa/-/execa-0.9.0.tgz",
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+      "dev": true,
+      "requires": {
+        "@types/body-parser": "*",
+        "@types/express-serve-static-core": "*",
+        "@types/serve-static": "*"
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+      "resolved": "https://registry.npmjs.org/@types/express-serve-static-core/-/express-serve-static-core-4.16.7.tgz",
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+      "requires": {
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+      "resolved": "https://registry.npmjs.org/@types/remove-markdown/-/remove-markdown-0.1.1.tgz",
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+      "version": "1.13.2",
+      "resolved": "https://registry.npmjs.org/@types/serve-static/-/serve-static-1.13.2.tgz",
+      "integrity": "sha512-/BZ4QRLpH/bNYgZgwhKEh+5AsboDBcUdlBYgzoLX0fpj3Y2gp6EApyOlM3bK53wQS/OE1SrdSYBAbux2D1528Q==",
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+      "requires": {
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diff --git a/package.json b/package.json
index c212fb9..e0afbc1 100644
--- a/package.json
+++ b/package.json
@@ -3,11 +3,42 @@
   "version": "2.0.0",
   "description": "Server for Algorithm Visualizer",
   "scripts": {
-    "test": "echo \"Error: no test specified\" && exit 1"
+    "watch": "NODE_ENV=development NODE_PATH=src ts-node-dev --respawn --ignore-watch node_modules --no-notify src",
+    "start": "NODE_ENV=production NODE_PATH=src ts-node --transpile-only src",
+    "tslint": "tslint -c tslint.json -p tsconfig.json"
   },
   "repository": {
     "type": "git",
     "url": "git+https://github.com/algorithm-visualizer/server.git"
   },
-  "license": "MIT"
+  "license": "MIT",
+  "devDependencies": {
+    "@types/compression": "0.0.36",
+    "@types/execa": "^0.9.0",
+    "@types/express": "^4.16.1",
+    "@types/fs-extra": "^7.0.0",
+    "@types/morgan": "^1.7.35",
+    "@types/node": "^12.0.0",
+    "@types/remove-markdown": "^0.1.1",
+    "@types/uuid": "^3.4.4",
+    "ts-node-dev": "^1.0.0-pre.39",
+    "tslint": "^5.16.0"
+  },
+  "dependencies": {
+    "axios": "^0.19.0",
+    "body-parser": "^1.18.2",
+    "compression": "^1.7.3",
+    "dotenv": "^8.0.0",
+    "dotenv-flow": "^2.0.0",
+    "execa": "^1.0.0",
+    "express": "^4.16.4",
+    "express-github-webhook": "^1.0.6",
+    "fs-extra": "^6.0.1",
+    "morgan": "^1.9.1",
+    "remove-markdown": "^0.3.0",
+    "ts-httpexceptions": "^4.1.0",
+    "ts-node": "^8.1.0",
+    "typescript": "^3.4.5",
+    "uuid": "^3.3.2"
+  }
 }
diff --git a/pm2.config.js b/pm2.config.js
deleted file mode 100644
index 92786cc..0000000
--- a/pm2.config.js
+++ /dev/null
@@ -1,23 +0,0 @@
-const env = {
-  NODE_ENV: 'production',
-  HTTP_PORT: '80',
-  HTTPS_PORT: '443',
-  GITHUB_CLIENT_ID: '4ca41e5d1e4ae21b6f75',
-  GITHUB_CLIENT_SECRET: '72fb530eb676b89a1a77e5371f8e21c5965f56ea',
-  GITHUB_WEBHOOK_SECRET: 'flapdoodle_blandiloquence',
-  CREDENTIALS_ENABLED: '1',
-  CREDENTIALS_PATH: '/etc/letsencrypt/live/algorithm-visualizer.org',
-  CREDENTIALS_CA: 'chain.pem',
-  CREDENTIALS_KEY: 'privkey.pem',
-  CREDENTIALS_CERT: 'cert.pem',
-};
-
-module.exports = {
-  apps: [
-    {
-      name: 'algorithm-visualizer',
-      script: 'npm run pm2',
-      env,
-    },
-  ],
-};
diff --git a/public/algorithm-visualizer.js b/public/algorithm-visualizer.js
deleted file mode 100644
index ff8035b..0000000
--- a/public/algorithm-visualizer.js
+++ /dev/null
@@ -1 +0,0 @@
-!function webpackUniversalModuleDefinition(t,r){"object"==typeof exports&&"object"==typeof module?module.exports=r():"function"==typeof define&&define.amd?define([],r):"object"==typeof exports?exports.AlgorithmVisualizer=r():t.AlgorithmVisualizer=r()}("undefined"!=typeof self?self:this,function(){return function(t){var r={};function __webpack_require__(e){if(r[e])return r[e].exports;var o=r[e]={i:e,l:!1,exports:{}};return t[e].call(o.exports,o,o.exports,__webpack_require__),o.l=!0,o.exports}return __webpack_require__.m=t,__webpack_require__.c=r,__webpack_require__.d=function(t,r,e){__webpack_require__.o(t,r)||Object.defineProperty(t,r,{enumerable:!0,get:e})},__webpack_require__.r=function(t){"undefined"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(t,Symbol.toStringTag,{value:"Module"}),Object.defineProperty(t,"__esModule",{value:!0})},__webpack_require__.t=function(t,r){if(1&r&&(t=__webpack_require__(t)),8&r)return t;if(4&r&&"object"==typeof t&&t&&t.__esModule)return 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d=e(13);r.GraphTracer=d.default},function(t,r,e){"use strict";var o=this&&this.__extends||function(){var t=function(r,e){return(t=Object.setPrototypeOf||{__proto__:[]}instanceof Array&&function(t,r){t.__proto__=r}||function(t,r){for(var e in r)r.hasOwnProperty(e)&&(t[e]=r[e])})(r,e)};return function(r,e){function __(){this.constructor=r}t(r,e),r.prototype=null===e?Object.create(e):(__.prototype=e.prototype,new __)}}();Object.defineProperty(r,"__esModule",{value:!0});var n=function(){function Randomizer(){}return Randomizer.prototype.create=function(){return null},Randomizer}(),a=function(t){function Integer(r,e){void 0===r&&(r=1),void 0===e&&(e=9);var o=t.call(this)||this;return o._min=r,o._max=e,o}return o(Integer,t),Integer.prototype.create=function(){return Math.random()*(this._max-this._min+1)+this._min|0},Integer}(n),i=(function(t){function Double(r,e){void 0===r&&(r=0),void 0===e&&(e=1);var o=t.call(this)||this;return o._min=r,o._max=e,o}o(Double,t),Double.prototype.create=function(){return Math.random()*(this._max-this._min)+this._min}}(n),function(t){function String(r,e){void 0===r&&(r=16),void 0===e&&(e="abcdefghijklmnopqrstuvwxyz");var o=t.call(this)||this;return o._length=r,o._letters=e,o}return o(String,t),String.prototype.create=function(){for(var t="",r=new a(0,this._letters.length-1),e=0;e<this._length;e++)t+=this._letters[r.create()];return t},String}(n)),c=function(t){function Array2D(r,e,o){void 0===r&&(r=10),void 0===e&&(e=10),void 0===o&&(o=new a);var n=t.call(this)||this;return n._N=r,n._M=e,n._randomizer=o,n._sorted=!1,n}return o(Array2D,t),Array2D.prototype.sorted=function(t){return void 0===t&&(t=!0),this._sorted=t,this},Array2D.prototype.create=function(){for(var t=[],r=0;r<this._N;r++){t.push([]);for(var e=0;e<this._M;e++)t[r].push(this._randomizer.create());this._sorted&&t[r].sort(function(t,r){return t-r})}return t},Array2D}(n),u=function(t){function Array1D(r,e){return t.call(this,1,r,e)||this}return o(Array1D,t),Array1D.prototype.create=function(){return t.prototype.create.call(this)[0]},Array1D}(c),p=function(t){function Graph(r,e,o){void 0===r&&(r=5),void 0===e&&(e=.3),void 0===o&&(o=new a);var n=t.call(this)||this;return n._N=r,n._ratio=e,n._randomizer=o,n._directed=!0,n._weighted=!1,n}return o(Graph,t),Graph.prototype.directed=function(t){return void 0===t&&(t=!0),this._directed=t,this},Graph.prototype.weighted=function(t){return void 0===t&&(t=!0),this._weighted=t,this},Graph.prototype.create=function(){for(var t=new Array(this._N),r=0;r<this._N;r++)t[r]=new Array(this._N);for(r=0;r<this._N;r++)for(var e=0;e<this._N;e++)r===e?t[r][e]=0:this._directed||r<e?t[r][e]=Math.random()<this._ratio?this._weighted?this._randomizer.create():1:0:t[r][e]=t[e][r];return t},Graph}(n);r.default={Integer:a,String:i,Array1D:u,Array2D:c,Graph:p}},function(t,r,e){"use strict";Object.defineProperty(r,"__esModule",{value:!0});var o=e(0),n=function(){function Commander(t){Commander.objectCount++;var r=this.constructor.name;this.key=Commander.keyRandomizer.create(),this.command(r,t)}return Commander.command=function(t,r,e){var o=Array.from(e);if(this.commands.push({key:t,method:r,args:JSON.parse(JSON.stringify(o))}),this.commands.length>1e6)throw new Error("Too Many Commands");if(this.objectCount>100)throw new Error("Too Many Objects")},Commander.prototype.destroy=function(){Commander.objectCount--,this.command("destroy",arguments)},Commander.prototype.command=function(t,r){Commander.command(this.key,t,r)},Commander.prototype.toJSON=function(){return this.key},Commander.keyRandomizer=new o.Randomize.String(8,"abcdefghijklmnopqrstuvwxyz0123456789"),Commander.objectCount=0,Commander.commands=[],Commander}();if(!process.env.ALGORITHM_VISUALIZER){var a=e(3),i=e(4);process.on("beforeExit",function(){a.post("https://algorithm-visualizer.org/api/visualizations",{content:JSON.stringify(n.commands)}).then(function(t){return i(t.data,{wait:!1})}).catch(console.error).finally(function(){return process.exit()})})}r.default=n},function(t,r){t.exports=require("axios")},function(t,r){t.exports=require("opn")},function(t,r,e){"use strict";var o=this&&this.__extends||function(){var t=function(r,e){return(t=Object.setPrototypeOf||{__proto__:[]}instanceof Array&&function(t,r){t.__proto__=r}||function(t,r){for(var e in r)r.hasOwnProperty(e)&&(t[e]=r[e])})(r,e)};return function(r,e){function __(){this.constructor=r}t(r,e),r.prototype=null===e?Object.create(e):(__.prototype=e.prototype,new __)}}();Object.defineProperty(r,"__esModule",{value:!0});var n=function(t){function Layout(r){return t.call(this,arguments)||this}return 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this.command("layoutRandom",arguments),this},GraphTracer.prototype.addNode=function(t,r,e,o,n,a){this.command("addNode",arguments)},GraphTracer.prototype.updateNode=function(t,r,e,o,n,a){this.command("updateNode",arguments)},GraphTracer.prototype.removeNode=function(t){this.command("removeNode",arguments)},GraphTracer.prototype.addEdge=function(t,r,e,o,n){this.command("addEdge",arguments)},GraphTracer.prototype.updateEdge=function(t,r,e,o,n){this.command("updateEdge",arguments)},GraphTracer.prototype.removeEdge=function(t,r){this.command("removeEdge",arguments)},GraphTracer.prototype.visit=function(t,r,e){this.command("visit",arguments)},GraphTracer.prototype.leave=function(t,r,e){this.command("leave",arguments)},GraphTracer.prototype.select=function(t,r){this.command("select",arguments)},GraphTracer.prototype.deselect=function(t,r){this.command("deselect",arguments)},GraphTracer.prototype.log=function(t){this.command("log",arguments)},GraphTracer}(e(0).Tracer);r.default=n}])});
\ No newline at end of file
diff --git a/public/codes/3fe76da7-b5cb-4925-8b32-9ff05204e78d/Main b/public/codes/3fe76da7-b5cb-4925-8b32-9ff05204e78d/Main
deleted file mode 100755
index 6bb425a..0000000
Binary files a/public/codes/3fe76da7-b5cb-4925-8b32-9ff05204e78d/Main and /dev/null differ
diff --git a/public/codes/3fe76da7-b5cb-4925-8b32-9ff05204e78d/Main.cpp b/public/codes/3fe76da7-b5cb-4925-8b32-9ff05204e78d/Main.cpp
deleted file mode 100644
index 3719b86..0000000
--- a/public/codes/3fe76da7-b5cb-4925-8b32-9ff05204e78d/Main.cpp
+++ /dev/null
@@ -1,22 +0,0 @@
-#include <string>
-#include <iostream>
-#include "algorithm-visualizer/GraphTracer.h"
-#include "algorithm-visualizer/Randomize.h"
-
-#define N 5
-
-using namespace std;
-
-int main() {
-    int array[N][N];
-    Randomize::Graph<int>(N, 1, *(new Randomize::Integer(1, 9))).weighted().directed(false).fill(&array[0][0]);
-    GraphTracer graphTracer;
-    graphTracer.set(array);
-    for (int i = 0; i < N; i++) {
-        for (int j = 0; j < N; j++) {
-            cout << array[i][j] << " ";
-        }
-        cout << endl;
-    }
-    return 0;
-}
diff --git a/src/Server.ts b/src/Server.ts
new file mode 100644
index 0000000..f478451
--- /dev/null
+++ b/src/Server.ts
@@ -0,0 +1,104 @@
+import express, { NextFunction, Request, Response } from 'express';
+import morgan from 'morgan';
+import bodyParser from 'body-parser';
+import * as Controllers from 'controllers';
+import { NotFound } from 'ts-httpexceptions';
+import compression from 'compression';
+import { __PROD__, credentials, httpPort, httpsPort, webhookOptions } from 'config/environments';
+import http from 'http';
+import https from 'https';
+import { Hierarchy } from 'models';
+import execa from 'execa';
+import * as Tracers from 'tracers';
+import { errorHandlerMiddleware, frontendMiddleware, redirectMiddleware } from 'middlewares';
+import { pull } from 'utils/misc';
+import { frontendBuildDir, frontendBuiltDir, frontendDir, rootDir } from 'config/paths';
+
+const Webhook = require('express-github-webhook');
+
+export default class Server {
+  private readonly app = express();
+  readonly hierarchy = new Hierarchy();
+  readonly tracers = Object.values(Tracers).map(Tracer => new Tracer());
+  private readonly webhook = webhookOptions && Webhook(webhookOptions);
+
+  constructor() {
+    this.app
+      .use(compression())
+      .use(morgan(__PROD__ ? 'tiny' : 'dev'))
+      .use(redirectMiddleware())
+      .use(bodyParser.json())
+      .use(bodyParser.urlencoded({extended: true}))
+      .use('/api', this.getApiRouter())
+      .use(frontendMiddleware(this));
+    if (this.webhook) {
+      this.app.use('/webhook', this.webhook);
+    }
+    this.app.use(errorHandlerMiddleware());
+
+    if (this.webhook) {
+      this.webhook.on('push', async (repo: string, data: any) => {
+        const {ref, head_commit} = data;
+        if (ref !== 'refs/heads/master') return;
+        if (!head_commit) throw new Error('The `head_commit` is empty.');
+
+        switch (repo) {
+          case 'server':
+            await this.update(head_commit.id);
+            break;
+          case 'algorithm-visualizer':
+            await this.updateFrontend(head_commit.id);
+            break;
+          case 'algorithms':
+            await this.hierarchy.update(head_commit.id);
+            break;
+          default:
+            throw new Error(`Webhook from unknown repository '${repo}'.`);
+        }
+      });
+
+      this.webhook.on('release', async (repo: string, data: any) => {
+        const tracer = this.tracers.find(tracer => repo === `tracers.${tracer.lang}`);
+        if (!tracer) throw new Error(`Tracer not found for repository '${repo}'.`);
+        await tracer.update(data.release);
+      });
+    }
+  }
+
+  getApiRouter() {
+    const router = express.Router();
+    Object.values(Controllers).forEach(Controller => new Controller(this).route(router));
+    router.use((req: Request, res: Response, next: NextFunction) => {
+      next(new NotFound('API not found.'));
+    });
+    return router;
+  };
+
+  async update(commit?: string) {
+    await pull(rootDir, 'server', commit);
+    await execa.shell('npm install', {cwd: rootDir});
+    process.exit(0);
+  };
+
+  async updateFrontend(commit?: string) {
+    await pull(frontendDir, 'algorithm-visualizer', commit);
+    await execa.shell([
+      'npm install',
+      'npm run build',
+      `rm -rf ${frontendBuiltDir}`,
+      `mv ${frontendBuildDir} ${frontendBuiltDir}`,
+    ].join(' && '), {cwd: frontendDir});
+  }
+
+  start() {
+    const httpServer = http.createServer(this.app);
+    httpServer.listen(httpPort);
+    console.info(`http: listening on port ${httpPort}`);
+
+    if (credentials) {
+      const httpsServer = https.createServer(credentials, this.app);
+      httpsServer.listen(httpsPort);
+      console.info(`https: listening on port ${httpsPort}`);
+    }
+  }
+}
diff --git a/src/apis/index.js b/src/apis/index.js
deleted file mode 100644
index 5aedb72..0000000
--- a/src/apis/index.js
+++ /dev/null
@@ -1,82 +0,0 @@
-import Promise from 'bluebird';
-import axios from 'axios';
-import fs from 'fs';
-import { githubClientId, githubClientSecret } from '/environment';
-
-const instance = axios.create();
-
-instance.interceptors.request.use(request => {
-  request.params = { client_id: githubClientId, client_secret: githubClientSecret, ...request.params };
-  return request;
-});
-
-instance.interceptors.response.use(response => {
-  return response.data;
-}, error => {
-  return Promise.reject(error.response.data);
-});
-
-const request = (url, process) => {
-  const tokens = url.split('/');
-  const baseURL = /^https?:\/\//i.test(url) ? '' : 'https://api.github.com';
-  return (...args) => {
-    return new Promise((resolve, reject) => {
-      const mappedURL = baseURL + tokens.map((token, i) => token.startsWith(':') ? args.shift() : token).join('/');
-      return resolve(process(mappedURL, args));
-    });
-  };
-};
-
-const GET = URL => {
-  return request(URL, (mappedURL, args) => {
-    const [params] = args;
-    return instance.get(mappedURL, { params });
-  });
-};
-
-const DELETE = URL => {
-  return request(URL, (mappedURL, args) => {
-    const [params] = args;
-    return instance.delete(mappedURL, { params });
-  });
-};
-
-const POST = URL => {
-  return request(URL, (mappedURL, args) => {
-    const [body, params] = args;
-    return instance.post(mappedURL, body, { params });
-  });
-};
-
-const PUT = URL => {
-  return request(URL, (mappedURL, args) => {
-    const [body, params] = args;
-    return instance.put(mappedURL, body, { params });
-  });
-};
-
-const PATCH = URL => {
-  return request(URL, (mappedURL, args) => {
-    const [body, params] = args;
-    return instance.patch(mappedURL, body, { params });
-  });
-};
-
-const GitHubApi = {
-  listCommits: GET('/repos/:owner/:repo/commits'),
-  getAccessToken: code => instance.post('https://github.com/login/oauth/access_token', { code }, { headers: { Accept: 'application/json' } }),
-  getLatestRelease: GET('/repos/:owner/:repo/releases/latest'),
-  download: (url, path) => instance({
-    method: 'get',
-    url,
-    responseType: 'stream',
-  }).then(data => new Promise((resolve, reject) => {
-    data.pipe(fs.createWriteStream(path));
-    data.on('end', resolve);
-    data.on('error', reject);
-  })),
-};
-
-export {
-  GitHubApi,
-};
\ No newline at end of file
diff --git a/src/common/config.js b/src/common/config.js
deleted file mode 100644
index 6e06a99..0000000
--- a/src/common/config.js
+++ /dev/null
@@ -1,7 +0,0 @@
-const memoryLimit = 256; // in megabytes
-const timeLimit = 5000; // in milliseconds
-
-export {
-  memoryLimit,
-  timeLimit,
-};
diff --git a/src/common/error.js b/src/common/error.js
deleted file mode 100644
index c089470..0000000
--- a/src/common/error.js
+++ /dev/null
@@ -1,18 +0,0 @@
-class ClientError extends Error {
-}
-
-class NotFoundError extends ClientError {
-}
-
-class ForbiddenError extends ClientError {
-}
-
-class UnauthorizedError extends ClientError {
-}
-
-export {
-  ClientError,
-  NotFoundError,
-  ForbiddenError,
-  UnauthorizedError,
-};
diff --git a/src/common/hierarchy.js b/src/common/hierarchy.js
deleted file mode 100644
index 61635f1..0000000
--- a/src/common/hierarchy.js
+++ /dev/null
@@ -1,7 +0,0 @@
-import { Hierarchy } from '/models';
-import path from 'path';
-
-const repoPath = path.resolve(__dirname, '..', 'public', 'algorithms');
-const hierarchy = new Hierarchy(repoPath);
-
-export default hierarchy;
diff --git a/src/common/util.js b/src/common/util.js
deleted file mode 100644
index 8c9ddfa..0000000
--- a/src/common/util.js
+++ /dev/null
@@ -1,52 +0,0 @@
-import Promise from 'bluebird';
-import axios from 'axios';
-import child_process from 'child_process';
-import path from 'path';
-import fs from 'fs-extra';
-import removeMarkdown from 'remove-markdown';
-
-const execute = (command, { stdout = process.stdout, stderr = process.stderr, ...options } = {}) => new Promise((resolve, reject) => {
-  const child = child_process.exec(command, options, (error, stdout, stderr) => {
-    if (error) return reject(error.code ? new Error(stderr) : error);
-    resolve(stdout);
-  });
-  if (stdout) child.stdout.pipe(stdout);
-  if (stderr) child.stderr.pipe(stderr);
-});
-
-const createKey = name => name.toLowerCase().trim().replace(/[^\w \-]/g, '').replace(/ /g, '-');
-
-const isDirectory = dirPath => fs.lstatSync(dirPath).isDirectory();
-
-const listFiles = dirPath => fs.readdirSync(dirPath).filter(fileName => !fileName.startsWith('.'));
-
-const listDirectories = dirPath => listFiles(dirPath).filter(fileName => isDirectory(path.resolve(dirPath, fileName)));
-
-const getDescription = files => {
-  const readmeFile = files.find(file => file.name === 'README.md');
-  if (!readmeFile) return '';
-  const lines = readmeFile.content.split('\n');
-  lines.shift();
-  while (lines.length && !lines[0].trim()) lines.shift();
-  let descriptionLines = [];
-  while (lines.length && lines[0].trim()) descriptionLines.push(lines.shift());
-  return removeMarkdown(descriptionLines.join(' '));
-};
-
-const download = (url, localPath) => axios({ url, method: 'GET', responseType: 'stream' })
-  .then(response => new Promise((resolve, reject) => {
-    const writer = fs.createWriteStream(localPath);
-    writer.on('finish', resolve);
-    writer.on('error', reject);
-    response.data.pipe(writer);
-  }));
-
-export {
-  execute,
-  createKey,
-  isDirectory,
-  listFiles,
-  listDirectories,
-  getDescription,
-  download,
-};
diff --git a/src/common/webhook.js b/src/common/webhook.js
deleted file mode 100644
index 5f7599a..0000000
--- a/src/common/webhook.js
+++ /dev/null
@@ -1,6 +0,0 @@
-import GithubWebHook from 'express-github-webhook';
-import { githubWebhookSecret } from '/environment';
-
-const webhook = GithubWebHook({ path: '/', secret: githubWebhookSecret });
-
-export default webhook;
diff --git a/src/config/constants.ts b/src/config/constants.ts
new file mode 100644
index 0000000..34f9787
--- /dev/null
+++ b/src/config/constants.ts
@@ -0,0 +1,2 @@
+export const memoryLimit = 256; // in megabytes
+export const timeLimit = 5000; // in milliseconds
diff --git a/src/config/environments.ts b/src/config/environments.ts
new file mode 100644
index 0000000..0a8ae31
--- /dev/null
+++ b/src/config/environments.ts
@@ -0,0 +1,73 @@
+import fs from 'fs';
+import { ServerOptions } from 'https';
+import path from 'path';
+
+require('dotenv-flow').config();
+
+declare var process: {
+  env: {
+    [key: string]: string,
+  }
+};
+
+const {
+  NODE_ENV,
+
+  HTTP_PORT,
+  HTTPS_PORT,
+
+  CREDENTIALS_ENABLED,
+  CREDENTIALS_PATH,
+  CREDENTIALS_CA,
+  CREDENTIALS_KEY,
+  CREDENTIALS_CERT,
+
+  WEBHOOK_ENABLED,
+  WEBHOOK_SECRET,
+
+  GITHUB_CLIENT_ID,
+  GITHUB_CLIENT_SECRET,
+} = process.env;
+
+const isEnabled = (v: string) => v === '1';
+
+const missingVars = [
+  'NODE_ENV',
+  'HTTP_PORT',
+  'HTTPS_PORT',
+  'CREDENTIALS_ENABLED',
+  ...(isEnabled(CREDENTIALS_ENABLED) ? [
+    'CREDENTIALS_PATH',
+    'CREDENTIALS_CA',
+    'CREDENTIALS_KEY',
+    'CREDENTIALS_CERT',
+  ] : []),
+  'WEBHOOK_ENABLED',
+  ...(isEnabled(WEBHOOK_ENABLED) ? [
+    'WEBHOOK_SECRET',
+  ] : []),
+  'GITHUB_CLIENT_ID',
+  'GITHUB_CLIENT_SECRET',
+].filter(variable => process.env[variable] === undefined);
+if (missingVars.length) throw new Error(`The following environment variables are missing: ${missingVars.join(', ')}`);
+
+export const __PROD__ = NODE_ENV === 'production';
+export const __DEV__ = NODE_ENV === 'development';
+
+export const httpPort = parseInt(HTTP_PORT);
+export const httpsPort = parseInt(HTTPS_PORT);
+
+export const webhookOptions = isEnabled(WEBHOOK_ENABLED) ? {
+  path: '/webhook',
+  secret: WEBHOOK_SECRET,
+} : undefined;
+
+const readCredentials = (file: string) => fs.readFileSync(path.resolve(CREDENTIALS_PATH, file));
+export const credentials: ServerOptions | undefined = isEnabled(CREDENTIALS_ENABLED) ? {
+  ca: readCredentials(CREDENTIALS_CA),
+  key: readCredentials(CREDENTIALS_KEY),
+  cert: readCredentials(CREDENTIALS_CERT),
+} : undefined;
+
+export const githubClientId = GITHUB_CLIENT_ID;
+export const githubClientSecret = GITHUB_CLIENT_SECRET;
diff --git a/src/config/paths.ts b/src/config/paths.ts
new file mode 100644
index 0000000..3d69c81
--- /dev/null
+++ b/src/config/paths.ts
@@ -0,0 +1,10 @@
+import path from 'path';
+
+export const rootDir = path.resolve(__dirname, '..', '..');
+export const publicDir = path.resolve(rootDir, 'public');
+export const algorithmsDir = path.resolve(publicDir, 'algorithms');
+export const codesDir = path.resolve(publicDir, 'codes');
+export const visualizationsDir = path.resolve(publicDir, 'visualizations');
+export const frontendDir = path.resolve(publicDir, 'frontend');
+export const frontendBuildDir = path.resolve(frontendDir, 'build');
+export const frontendBuiltDir = path.resolve(publicDir, 'frontend-built');
diff --git a/src/controllers/AlgorithmsController.ts b/src/controllers/AlgorithmsController.ts
new file mode 100644
index 0000000..3db320b
--- /dev/null
+++ b/src/controllers/AlgorithmsController.ts
@@ -0,0 +1,38 @@
+import express from 'express';
+import { Controller } from 'controllers/Controller';
+import { NotFound } from 'ts-httpexceptions';
+import Server from 'Server';
+
+export class AlgorithmsController extends Controller {
+  constructor(server: Server) {
+    super(server);
+    this.router
+      .get('/', this.getHierarchy)
+      .get('/:categoryKey/:algorithmKey', this.getAlgorithm)
+      .get('/sitemap.txt', this.getSitemap);
+  }
+
+  route = (router: express.Router): void => {
+    router.use('/algorithms', this.router);
+  };
+
+  getHierarchy = (req: express.Request, res: express.Response) => {
+    res.json(this.server.hierarchy);
+  };
+
+  getAlgorithm = (req: express.Request, res: express.Response, next: express.NextFunction) => {
+    const {categoryKey, algorithmKey} = req.params;
+    const algorithm = this.server.hierarchy.find(categoryKey, algorithmKey);
+    if (!algorithm) return next(new NotFound('Algorithm not found.'));
+    res.json({algorithm});
+  };
+
+  getSitemap = (req: express.Request, res: express.Response) => {
+    const urls: string[] = [];
+    this.server.hierarchy.iterate((category, algorithm) => {
+      urls.push(`https://algorithm-visualizer.org/${category.key}/${algorithm.key}`);
+    });
+    res.set('Content-Type', 'text/plain');
+    res.send(urls.join('\n'));
+  };
+}
diff --git a/src/controllers/AuthController.ts b/src/controllers/AuthController.ts
new file mode 100644
index 0000000..74080ed
--- /dev/null
+++ b/src/controllers/AuthController.ts
@@ -0,0 +1,36 @@
+import express from 'express';
+import { githubClientId } from 'config/environments';
+import { GitHubApi } from 'utils/apis';
+import { Controller } from 'controllers/Controller';
+import Server from 'Server';
+
+export class AuthController extends Controller {
+  constructor(server: Server) {
+    super(server);
+    this.router
+      .get('/request', this.request)
+      .get('/response', this.response)
+      .get('/destroy', this.destroy);
+  }
+
+  route = (router: express.Router): void => {
+    router.use('/auth', this.router);
+  };
+
+  request = (req: express.Request, res: express.Response) => {
+    res.redirect(`https://github.com/login/oauth/authorize?client_id=${githubClientId}&scope=user,gist`);
+  };
+
+  response = (req: express.Request, res: express.Response, next: express.NextFunction) => {
+    const {code} = req.query;
+
+    GitHubApi.getAccessToken(code).then(({data}) => {
+      const {access_token} = data;
+      res.send(`<script>window.opener.signIn('${access_token}');window.close();</script>`);
+    }).catch(next);
+  };
+
+  destroy = (req: express.Request, res: express.Response) => {
+    res.send(`<script>window.opener.signOut();window.close();</script>`);
+  };
+}
diff --git a/src/controllers/Controller.ts b/src/controllers/Controller.ts
new file mode 100644
index 0000000..9be63b6
--- /dev/null
+++ b/src/controllers/Controller.ts
@@ -0,0 +1,12 @@
+import express from "express";
+import Server from 'Server';
+
+export abstract class Controller {
+  protected readonly router: express.Router;
+
+  protected constructor(protected server: Server) {
+    this.router = express.Router();
+  }
+
+  abstract route(router: express.Router): void;
+}
diff --git a/src/controllers/TracersController.ts b/src/controllers/TracersController.ts
new file mode 100644
index 0000000..51a4070
--- /dev/null
+++ b/src/controllers/TracersController.ts
@@ -0,0 +1,14 @@
+import express from 'express';
+import { Controller } from 'controllers/Controller';
+import Server from 'Server';
+
+export class TracersController extends Controller {
+  constructor(server: Server) {
+    super(server);
+    this.server.tracers.forEach(tracer => tracer.route(this.router));
+  }
+
+  route = (router: express.Router): void => {
+    router.use('/tracers', this.router);
+  };
+}
diff --git a/src/controllers/VisualizationsController.ts b/src/controllers/VisualizationsController.ts
new file mode 100644
index 0000000..3b9cfa9
--- /dev/null
+++ b/src/controllers/VisualizationsController.ts
@@ -0,0 +1,41 @@
+import express from 'express';
+import path from 'path';
+import uuid from 'uuid';
+import fs from 'fs-extra';
+import { Controller } from 'controllers/Controller';
+import Server from 'Server';
+import { visualizationsDir } from 'config/paths';
+
+export class VisualizationsController extends Controller {
+  constructor(server: Server) {
+    super(server);
+    this.router
+      .post('/', this.uploadVisualization)
+      .get('/:visualizationId', this.getVisualization);
+
+    fs.remove(visualizationsDir).catch(console.error);
+  }
+
+  route = (router: express.Router): void => {
+    router.use('/visualizations', this.router);
+  };
+
+  uploadVisualization = (req: express.Request, res: express.Response, next: express.NextFunction) => {
+    const {content} = req.body;
+    const visualizationId = uuid.v4();
+    const visualizationPath = path.resolve(visualizationsDir, `${visualizationId}.json`);
+    const url = `https://algorithm-visualizer.org/scratch-paper/new?visualizationId=${visualizationId}`;
+    fs.outputFile(visualizationPath, content)
+      .then(() => res.send(url))
+      .catch(next);
+  };
+
+  getVisualization = (req: express.Request, res: express.Response, next: express.NextFunction) => {
+    const {visualizationId} = req.params;
+    const visualizationPath = path.resolve(visualizationsDir, `${visualizationId}.json`);
+    res.sendFile(visualizationPath, err => {
+      if (err) next(new Error('Visualization Expired'));
+      fs.remove(visualizationPath);
+    });
+  };
+}
diff --git a/src/controllers/algorithms.js b/src/controllers/algorithms.js
deleted file mode 100644
index 6bac374..0000000
--- a/src/controllers/algorithms.js
+++ /dev/null
@@ -1,49 +0,0 @@
-import express from 'express';
-import fs from 'fs-extra';
-import { execute } from '/common/util';
-import webhook from '/common/webhook';
-import hierarchy from '/common/hierarchy';
-import { NotFoundError } from '/common/error';
-
-const router = express.Router();
-
-const downloadCategories = () => (
-  fs.pathExistsSync(hierarchy.path) ?
-    execute(`git fetch && git reset --hard origin/master`, { cwd: hierarchy.path }) :
-    execute(`git clone https://github.com/algorithm-visualizer/algorithms.git ${hierarchy.path}`)
-).then(() => hierarchy.refresh());
-
-downloadCategories().catch(console.error);
-
-webhook.on('algorithms', event => {
-  switch (event) {
-    case 'push':
-      downloadCategories().catch(console.error);
-      break;
-  }
-});
-
-router.route('/')
-  .get((req, res, next) => {
-    res.json(hierarchy);
-  });
-
-router.route('/:categoryKey/:algorithmKey')
-  .get((req, res, next) => {
-    const { categoryKey, algorithmKey } = req.params;
-    const algorithm = hierarchy.find(categoryKey, algorithmKey);
-    if (!algorithm) return next(new NotFoundError());
-    res.json({ algorithm });
-  });
-
-router.route('/sitemap.txt')
-  .get((req, res, next) => {
-    const urls = [];
-    hierarchy.iterate((category, algorithm) => {
-      urls.push(`https://algorithm-visualizer.org/${category.key}/${algorithm.key}`);
-    });
-    res.set('Content-Type', 'text/plain');
-    res.send(urls.join('\n'));
-  });
-
-export default router;
diff --git a/src/controllers/auth.js b/src/controllers/auth.js
deleted file mode 100644
index 45e156e..0000000
--- a/src/controllers/auth.js
+++ /dev/null
@@ -1,32 +0,0 @@
-import express from 'express';
-import { githubClientId } from '/environment';
-import { GitHubApi } from '/apis';
-
-const router = express.Router();
-
-const request = (req, res, next) => {
-  res.redirect(`https://github.com/login/oauth/authorize?client_id=${githubClientId}&scope=user,gist`);
-};
-
-const response = (req, res, next) => {
-  const { code } = req.query;
-
-  GitHubApi.getAccessToken(code).then(({ access_token }) => {
-    res.send(`<script>window.opener.signIn('${access_token}');window.close();</script>`);
-  }).catch(next);
-};
-
-const destroy = (req, res, next) => {
-  res.send(`<script>window.opener.signOut();window.close();</script>`);
-};
-
-router.route('/request')
-  .get(request);
-
-router.route('/response')
-  .get(response);
-
-router.route('/destroy')
-  .get(destroy);
-
-export default router;
diff --git a/src/controllers/index.js b/src/controllers/index.js
deleted file mode 100644
index a971818..0000000
--- a/src/controllers/index.js
+++ /dev/null
@@ -1,4 +0,0 @@
-export { default as auth } from './auth';
-export { default as algorithms } from './algorithms';
-export { default as tracers } from './tracers';
-export { default as visualizations } from './visualizations';
diff --git a/src/controllers/index.ts b/src/controllers/index.ts
new file mode 100644
index 0000000..7d3ebf0
--- /dev/null
+++ b/src/controllers/index.ts
@@ -0,0 +1,4 @@
+export { AlgorithmsController } from './AlgorithmsController';
+export { AuthController } from './AuthController';
+export { TracersController } from './TracersController';
+export { VisualizationsController } from './VisualizationsController';
diff --git a/src/controllers/tracers.js b/src/controllers/tracers.js
deleted file mode 100644
index 04806e4..0000000
--- a/src/controllers/tracers.js
+++ /dev/null
@@ -1,81 +0,0 @@
-import express from 'express';
-import fs from 'fs-extra';
-import Promise from 'bluebird';
-import uuid from 'uuid';
-import path from 'path';
-import { GitHubApi } from '/apis';
-import { execute } from '/common/util';
-import webhook from '/common/webhook';
-import { ImageBuilder, WorkerBuilder } from '/tracers';
-import { memoryLimit, timeLimit } from '/common/config';
-
-const router = express.Router();
-
-const trace = lang => (req, res, next) => {
-  const { code } = req.body;
-  const tempPath = path.resolve(__dirname, '..', 'public', 'codes', uuid.v4());
-  fs.outputFile(path.resolve(tempPath, `Main.${lang}`), code)
-    .then(() => {
-      const builder = builderMap[lang];
-      const containerName = uuid.v4();
-      let killed = false;
-      const timer = setTimeout(() => {
-        execute(`docker kill ${containerName}`).then(() => {
-          killed = true;
-        });
-      }, timeLimit);
-      return execute([
-        'docker run --rm',
-        `--name=${containerName}`,
-        '-w=/usr/visualization',
-        `-v=${tempPath}:/usr/visualization:rw`,
-        `-m=${memoryLimit}m`,
-        '-e ALGORITHM_VISUALIZER=1',
-        builder.imageName,
-      ].join(' '), { stdout: null, stderr: null }).catch(error => {
-        if (killed) throw new Error('Time Limit Exceeded');
-        throw error;
-      }).finally(() => clearTimeout(timer));
-    })
-    .then(() => new Promise((resolve, reject) => {
-      const visualizationPath = path.resolve(tempPath, 'visualization.json');
-      res.sendFile(visualizationPath, err => {
-        if (err) return reject(new Error('Visualization Not Found'));
-        resolve();
-      });
-    }))
-    .catch(next)
-    .finally(() => fs.remove(tempPath));
-};
-
-const builderMap = {
-  js: new WorkerBuilder(),
-  cpp: new ImageBuilder('cpp'),
-  java: new ImageBuilder('java'),
-};
-
-Promise.map(Object.keys(builderMap), lang => {
-  const builder = builderMap[lang];
-  return GitHubApi.getLatestRelease('algorithm-visualizer', `tracers.${lang}`).then(builder.build);
-}).catch(console.error);
-
-webhook.on('release', (repo, data) => {
-  const result = /^tracers\.(\w+)$/.exec(repo);
-  if (result) {
-    const [, lang] = result;
-    const builder = builderMap[lang];
-    builder.build(data.release).catch(console.error);
-  }
-});
-
-Object.keys(builderMap).forEach(lang => {
-  const builder = builderMap[lang];
-  if (builder instanceof ImageBuilder) {
-    router.post(`/${lang}`, trace(lang));
-  } else if (builder instanceof WorkerBuilder) {
-    router.get(`/${lang}`, (req, res) => res.sendFile(builder.tracerPath));
-    router.get(`/${lang}/worker`, (req, res) => res.sendFile(builder.workerPath));
-  }
-});
-
-export default router;
diff --git a/src/controllers/visualizations.js b/src/controllers/visualizations.js
deleted file mode 100644
index 968f78a..0000000
--- a/src/controllers/visualizations.js
+++ /dev/null
@@ -1,42 +0,0 @@
-import express from 'express';
-import path from 'path';
-import uuid from 'uuid';
-import fs from 'fs-extra';
-import Promise from 'bluebird';
-
-const router = express.Router();
-
-const uploadPath = path.resolve(__dirname, '..', 'public', 'visualizations');
-const getVisualizationPath = visualizationId => path.resolve(uploadPath, `${visualizationId}.json`);
-
-fs.remove(uploadPath).catch(console.error);
-
-const uploadVisualization = (req, res, next) => {
-  const { content } = req.body;
-  const visualizationId = uuid.v4();
-  const tracesPath = getVisualizationPath(visualizationId);
-  const url = `https://algorithm-visualizer.org/scratch-paper/new?visualizationId=${visualizationId}`;
-  fs.outputFile(tracesPath, content)
-    .then(() => res.send(url))
-    .catch(next);
-};
-
-const getVisualization = (req, res, next) => {
-  const { visualizationId } = req.params;
-  const visualizationPath = getVisualizationPath(visualizationId);
-  new Promise((resolve, reject) => {
-    res.sendFile(visualizationPath, err => {
-      if (err) return reject(new Error('Visualization Expired'));
-      resolve();
-    });
-  }).catch(next)
-    .finally(() => fs.remove(visualizationPath));
-};
-
-router.route('/')
-  .post(uploadVisualization);
-
-router.route('/:visualizationId')
-  .get(getVisualization);
-
-export default router;
diff --git a/src/index.js b/src/index.js
deleted file mode 100644
index 3f9df62..0000000
--- a/src/index.js
+++ /dev/null
@@ -1,41 +0,0 @@
-import express from 'express';
-import morgan from 'morgan';
-import cookieParser from 'cookie-parser';
-import bodyParser from 'body-parser';
-import * as controllers from '/controllers';
-import { ClientError, ForbiddenError, NotFoundError, UnauthorizedError } from '/common/error';
-import webhook from '/common/webhook';
-import hierarchy from '/common/hierarchy';
-
-const app = express();
-app.use(morgan('tiny'));
-app.use(cookieParser());
-app.use(bodyParser.json());
-app.use(bodyParser.urlencoded({ extended: true }));
-Object.keys(controllers).forEach(key => app.use(`/${key}`, controllers[key]));
-app.use('/webhook', webhook);
-app.use((req, res, next) => next(new NotFoundError()));
-app.use((err, req, res, next) => {
-  const statusMap = [
-    [UnauthorizedError, 401],
-    [ForbiddenError, 403],
-    [NotFoundError, 404],
-    [ClientError, 400],
-    [Error, 500],
-  ];
-  const [, status] = statusMap.find(([Error]) => err instanceof Error);
-  res.status(status);
-  res.send(err.message);
-  console.error(err);
-});
-app.hierarchy = hierarchy;
-
-webhook.on('algorithm-visualizer', event => {
-  switch (event) {
-    case 'push':
-      process.exit(0);
-      break;
-  }
-});
-
-export default app;
diff --git a/src/index.ts b/src/index.ts
new file mode 100644
index 0000000..329043e
--- /dev/null
+++ b/src/index.ts
@@ -0,0 +1,3 @@
+import Server from 'Server';
+
+new Server().start();
diff --git a/src/middlewares/errorHandlerMiddleware.ts b/src/middlewares/errorHandlerMiddleware.ts
new file mode 100644
index 0000000..8a1936a
--- /dev/null
+++ b/src/middlewares/errorHandlerMiddleware.ts
@@ -0,0 +1,14 @@
+import { NextFunction, Request, Response } from 'express';
+import { Exception, InternalServerError } from 'ts-httpexceptions';
+
+export function errorHandlerMiddleware() {
+  return (err: any, req: Request, res: Response, next: NextFunction) => {
+    if (!(err instanceof Exception)) {
+      console.error(err);
+      err = new InternalServerError(err.message, err);
+    }
+
+    const {name, message, status} = err;
+    res.status(status).json({name, message, status});
+  };
+}
diff --git a/src/middlewares/frontendMiddleware.ts b/src/middlewares/frontendMiddleware.ts
new file mode 100644
index 0000000..d793b1c
--- /dev/null
+++ b/src/middlewares/frontendMiddleware.ts
@@ -0,0 +1,51 @@
+import express, { NextFunction, Request, Response } from 'express';
+import path from 'path';
+import fs from 'fs-extra';
+import url from 'url';
+import Server from 'Server';
+import { frontendBuiltDir } from 'config/paths';
+
+const packageJson = require('../../package.json');
+
+export function frontendMiddleware(server: Server) {
+  const staticMiddleware = express.static(frontendBuiltDir, {index: false});
+
+  if (!fs.pathExistsSync(frontendBuiltDir)) {
+    server.updateFrontend().catch(console.error);
+  }
+
+  return (req: Request, res: Response, next: NextFunction) => {
+    staticMiddleware(req, res, err => {
+      if (err) return next(err);
+      if (req.method !== 'GET') return next();
+
+      const filePath = path.resolve(frontendBuiltDir, 'index.html');
+      fs.readFile(filePath, 'utf8', (err, data) => {
+        if (err) return next(err);
+
+        const {pathname} = url.parse(req.originalUrl);
+        if (!pathname) return next(new Error('Failed to get `pathname`.'));
+        const [, categoryKey, algorithmKey] = pathname.split('/');
+        let {title, description} = packageJson;
+        let algorithm = undefined;
+        if (categoryKey && categoryKey !== 'scratch-paper') {
+          algorithm = server.hierarchy.find(categoryKey, algorithmKey) || null;
+          if (algorithm) {
+            title = [algorithm.categoryName, algorithm.algorithmName].join(' - ');
+            description = algorithm.description;
+          } else {
+            res.status(404);
+            return;
+          }
+        }
+
+        const indexFile = data
+          .replace(/\$TITLE/g, title)
+          .replace(/\$DESCRIPTION/g, description)
+          .replace(/\$ALGORITHM/g, algorithm === undefined ? 'undefined' :
+            JSON.stringify(algorithm).replace(/</g, '\\u003c'));
+        res.send(indexFile);
+      });
+    });
+  };
+}
diff --git a/src/middlewares/index.ts b/src/middlewares/index.ts
new file mode 100644
index 0000000..67a71ec
--- /dev/null
+++ b/src/middlewares/index.ts
@@ -0,0 +1,3 @@
+export { errorHandlerMiddleware } from './errorHandlerMiddleware';
+export { frontendMiddleware } from './frontendMiddleware';
+export { redirectMiddleware } from './redirectMiddleware';
diff --git a/src/middlewares/redirectMiddleware.ts b/src/middlewares/redirectMiddleware.ts
new file mode 100644
index 0000000..6029f80
--- /dev/null
+++ b/src/middlewares/redirectMiddleware.ts
@@ -0,0 +1,14 @@
+import { NextFunction, Request, Response } from 'express';
+import { credentials } from 'config/environments';
+
+export function redirectMiddleware() {
+  return (req: Request, res: Response, next: NextFunction) => {
+    if (req.hostname === 'algo-visualizer.jasonpark.me') {
+      res.redirect(301, 'https://algorithm-visualizer.org/');
+    } else if (credentials && !req.secure) {
+      res.redirect(301, `https://${req.hostname}${req.url}`);
+    } else {
+      next();
+    }
+  };
+}
diff --git a/src/models/Algorithm.js b/src/models/Algorithm.js
deleted file mode 100644
index 45dfde2..0000000
--- a/src/models/Algorithm.js
+++ /dev/null
@@ -1,25 +0,0 @@
-import path from 'path';
-import { createKey, getDescription, listFiles } from '/common/util';
-import { File } from '/models';
-
-class Algorithm {
-  constructor(path, name) {
-    this.path = path;
-    this.key = createKey(name);
-    this.name = name;
-    this.refresh();
-  }
-
-  refresh() {
-    this.files = listFiles(this.path)
-      .map(fileName => new File(path.resolve(this.path, fileName), fileName));
-    this.description = getDescription(this.files);
-  }
-
-  toJSON() {
-    const { key, name } = this;
-    return { key, name };
-  }
-}
-
-export default Algorithm;
diff --git a/src/models/Algorithm.ts b/src/models/Algorithm.ts
new file mode 100644
index 0000000..d886799
--- /dev/null
+++ b/src/models/Algorithm.ts
@@ -0,0 +1,26 @@
+import path from 'path';
+import { createKey, listFiles } from 'utils/hierarchy';
+import { File } from 'models';
+import { getDescription } from 'utils/misc';
+
+export class Algorithm {
+  key: string;
+  files!: File[];
+  description!: string;
+
+  constructor(private path: string, public name: string) {
+    this.key = createKey(name);
+    this.refresh();
+  }
+
+  refresh() {
+    this.files = listFiles(this.path)
+      .map(fileName => new File(path.resolve(this.path, fileName), fileName));
+    this.description = getDescription(this.files);
+  }
+
+  toJSON() {
+    const {key, name} = this;
+    return {key, name};
+  }
+}
diff --git a/src/models/Category.js b/src/models/Category.js
deleted file mode 100644
index 03ea980..0000000
--- a/src/models/Category.js
+++ /dev/null
@@ -1,24 +0,0 @@
-import path from 'path';
-import { createKey, listDirectories } from '/common/util';
-import { Algorithm } from '/models';
-
-class Category {
-  constructor(path, name) {
-    this.path = path;
-    this.key = createKey(name);
-    this.name = name;
-    this.refresh();
-  }
-
-  refresh() {
-    this.algorithms = listDirectories(this.path)
-      .map(algorithmName => new Algorithm(path.resolve(this.path, algorithmName), algorithmName));
-  }
-
-  toJSON() {
-    const { key, name, algorithms } = this;
-    return { key, name, algorithms };
-  }
-}
-
-export default Category;
diff --git a/src/models/Category.ts b/src/models/Category.ts
new file mode 100644
index 0000000..52c9048
--- /dev/null
+++ b/src/models/Category.ts
@@ -0,0 +1,25 @@
+import path from 'path';
+import { createKey, listDirectories } from 'utils/hierarchy';
+import { Algorithm } from 'models';
+
+export class Category {
+  key: string;
+  algorithms!: Algorithm[];
+
+  constructor(private path: string, public name: string) {
+    this.key = createKey(name);
+    this.refresh();
+  }
+
+  refresh() {
+    this.algorithms = listDirectories(this.path)
+      .map(algorithmName => new Algorithm(path.resolve(this.path, algorithmName), algorithmName));
+  }
+
+  toJSON() {
+    const {key, name, algorithms} = this;
+    return {key, name, algorithms};
+  }
+}
+
+export default Category;
diff --git a/src/models/File.js b/src/models/File.js
deleted file mode 100644
index 3bb69da..0000000
--- a/src/models/File.js
+++ /dev/null
@@ -1,21 +0,0 @@
-import fs from 'fs-extra';
-
-class File {
-  constructor(path, name) {
-    this.path = path;
-    this.name = name;
-    this.refresh();
-  }
-
-  refresh() {
-    this.content = fs.readFileSync(this.path, 'utf-8');
-    this.contributors = [];
-  }
-
-  toJSON() {
-    const { name, content, contributors } = this;
-    return { name, content, contributors };
-  }
-}
-
-export default File;
diff --git a/src/models/File.ts b/src/models/File.ts
new file mode 100644
index 0000000..d97aa26
--- /dev/null
+++ b/src/models/File.ts
@@ -0,0 +1,25 @@
+import fs from 'fs-extra';
+
+export type Author = {
+  login: string,
+  avatar_url: string,
+}
+
+export class File {
+  content!: string;
+  contributors!: Author[];
+
+  constructor(public path: string, public name: string) {
+    this.refresh();
+  }
+
+  refresh() {
+    this.content = fs.readFileSync(this.path, 'utf-8');
+    this.contributors = [];
+  }
+
+  toJSON() {
+    const {name, content, contributors} = this;
+    return {name, content, contributors};
+  }
+}
diff --git a/src/models/Hierarchy.js b/src/models/Hierarchy.js
deleted file mode 100644
index 589910e..0000000
--- a/src/models/Hierarchy.js
+++ /dev/null
@@ -1,84 +0,0 @@
-import Promise from 'bluebird';
-import path from 'path';
-import { execute, listDirectories } from '/common/util';
-import { GitHubApi } from '/apis';
-import { Category } from '/models';
-
-class Hierarchy {
-  constructor(path) {
-    this.path = path;
-    this.refresh();
-  }
-
-  refresh() {
-    this.categories = listDirectories(this.path)
-      .map(categoryName => new Category(path.resolve(this.path, categoryName), categoryName));
-
-    const files = [];
-    this.categories.forEach(category => category.algorithms.forEach(algorithm => files.push(...algorithm.files)));
-    this.cacheCommitAuthors().then(commitAuthors => this.cacheContributors(files, commitAuthors));
-  }
-
-  cacheCommitAuthors(page = 1, commitAuthors = {}) {
-    const per_page = 100;
-    return GitHubApi.listCommits('algorithm-visualizer', 'algorithms', {
-      per_page,
-      page,
-    }).then(commits => {
-      commits.forEach(({ sha, commit, author }) => {
-        if (!author) return;
-        const { login, avatar_url } = author;
-        commitAuthors[sha] = { login, avatar_url };
-      });
-      if (commits.length < per_page) {
-        return commitAuthors;
-      } else {
-        return this.cacheCommitAuthors(page + 1, commitAuthors);
-      }
-    });
-  }
-
-  cacheContributors(files, commitAuthors) {
-    return Promise.each(files, file => {
-      return execute(`git --no-pager log --follow --no-merges --format="%H" "${file.path}"`, {
-        cwd: this.path, stdout: null,
-      }).then(stdout => {
-        const output = stdout.toString().replace(/\n$/, '');
-        const shas = output.split('\n').reverse();
-        const contributors = [];
-        for (const sha of shas) {
-          const author = commitAuthors[sha];
-          if (author && !contributors.find(contributor => contributor.login === author.login)) {
-            contributors.push(author);
-          }
-        }
-        file.contributors = contributors;
-      });
-    });
-  }
-
-  find(categoryKey, algorithmKey) {
-    const category = this.categories.find(category => category.key === categoryKey);
-    if (!category) return;
-    const algorithm = category.algorithms.find(algorithm => algorithm.key === algorithmKey);
-    if (!algorithm) return;
-
-    const categoryName = category.name;
-    const algorithmName = algorithm.name;
-    const files = algorithm.files;
-    const description = algorithm.description;
-
-    return { categoryKey, categoryName, algorithmKey, algorithmName, files, description };
-  }
-
-  iterate(callback) {
-    this.categories.forEach(category => category.algorithms.forEach(algorithm => callback(category, algorithm)));
-  }
-
-  toJSON() {
-    const { categories } = this;
-    return { categories };
-  }
-}
-
-export default Hierarchy;
diff --git a/src/models/Hierarchy.ts b/src/models/Hierarchy.ts
new file mode 100644
index 0000000..c5d6ff1
--- /dev/null
+++ b/src/models/Hierarchy.ts
@@ -0,0 +1,93 @@
+import path from 'path';
+import { listDirectories } from 'utils/hierarchy';
+import { GitHubApi } from 'utils/apis';
+import { Algorithm, Category, File } from 'models';
+import { Author } from 'models/File';
+import { algorithmsDir } from 'config/paths';
+import { pull } from 'utils/misc';
+import execa from 'execa';
+
+type CommitAuthors = {
+  [sha: string]: Author,
+}
+
+export class Hierarchy {
+  private categories!: Category[];
+  readonly path: string = algorithmsDir;
+
+  constructor() {
+    this.refresh();
+    this.update().catch(console.error);
+  }
+
+  refresh() {
+    this.categories = listDirectories(this.path)
+      .map(categoryName => new Category(path.resolve(this.path, categoryName), categoryName));
+
+    const files: File[] = [];
+    this.categories.forEach(category => category.algorithms.forEach(algorithm => files.push(...algorithm.files)));
+    this.cacheCommitAuthors().then(commitAuthors => this.cacheContributors(files, commitAuthors));
+  }
+
+  async update(commit?: string) {
+    await pull(this.path, 'algorithms', commit);
+    this.refresh();
+  };
+
+  async cacheCommitAuthors(page = 1, commitAuthors: CommitAuthors = {}): Promise<CommitAuthors> {
+    const per_page = 100;
+    const {data} = await GitHubApi.listCommits('algorithm-visualizer', 'algorithms', {per_page, page});
+    const commits: any[] = data;
+    for (const {sha, author} of commits) {
+      if (!author) continue;
+      const {login, avatar_url} = author;
+      commitAuthors[sha] = {login, avatar_url};
+    }
+    if (commits.length < per_page) {
+      return commitAuthors;
+    } else {
+      return this.cacheCommitAuthors(page + 1, commitAuthors);
+    }
+  }
+
+  async cacheContributors(files: File[], commitAuthors: CommitAuthors) {
+    for (const file of files) {
+      const stdout = await execa('git', ['--no-pager', 'log', '--follow', '--no-merges', '--format="%H"', '--', `"${file.path}"`], {
+        cwd: this.path,
+      });
+      const output = stdout.toString().replace(/\n$/, '');
+      const shas = output.split('\n').reverse();
+      const contributors: Author[] = [];
+      for (const sha of shas) {
+        const author = commitAuthors[sha];
+        if (author && !contributors.find(contributor => contributor.login === author.login)) {
+          contributors.push(author);
+        }
+      }
+      file.contributors = contributors;
+    }
+  }
+
+  find(categoryKey: string, algorithmKey: string) {
+    const category = this.categories.find(category => category.key === categoryKey);
+    if (!category) return;
+    const algorithm = category.algorithms.find(algorithm => algorithm.key === algorithmKey);
+    if (!algorithm) return;
+
+    const categoryName = category.name;
+    const algorithmName = algorithm.name;
+    const files = algorithm.files;
+    const description = algorithm.description;
+
+    return {categoryKey, categoryName, algorithmKey, algorithmName, files, description};
+  }
+
+  iterate(callback: (category: Category, algorithm: Algorithm) => void) {
+    this.categories.forEach(category => category.algorithms.forEach(algorithm => callback(category, algorithm)));
+  }
+
+  toJSON() {
+    const {categories} = this;
+    return {categories};
+  }
+}
diff --git a/src/models/index.js b/src/models/index.js
deleted file mode 100644
index 64dea13..0000000
--- a/src/models/index.js
+++ /dev/null
@@ -1,4 +0,0 @@
-export { default as Algorithm } from './Algorithm';
-export { default as Category } from './Category';
-export { default as File } from './File';
-export { default as Hierarchy } from './Hierarchy';
diff --git a/src/models/index.ts b/src/models/index.ts
new file mode 100644
index 0000000..4ace972
--- /dev/null
+++ b/src/models/index.ts
@@ -0,0 +1,4 @@
+export { Algorithm } from './Algorithm';
+export { Category } from './Category';
+export { File } from './File';
+export { Hierarchy } from './Hierarchy';
diff --git a/src/tracers/DockerTracer.ts b/src/tracers/DockerTracer.ts
new file mode 100644
index 0000000..ae40663
--- /dev/null
+++ b/src/tracers/DockerTracer.ts
@@ -0,0 +1,64 @@
+import path from 'path';
+import { Release, Tracer } from 'tracers/Tracer';
+import express from 'express';
+import uuid from 'uuid';
+import fs from 'fs-extra';
+import { memoryLimit, timeLimit } from 'config/constants';
+import { codesDir } from 'config/paths';
+import execa = require('execa');
+
+export class DockerTracer extends Tracer {
+  private readonly directory: string;
+  private readonly imageName: string;
+
+  constructor(lang: string) {
+    super(lang);
+    this.directory = path.resolve(__dirname, lang);
+    this.imageName = `tracer-${this.lang}`;
+
+    this.build = this.build.bind(this);
+  }
+
+  build(release: Release) {
+    const {tag_name} = release;
+    return execa('docker', ['build', '-t', this.imageName, '.', '--build-arg', `tag_name=${tag_name}`], {cwd: this.directory});
+  }
+
+  route(router: express.Router) {
+    router.post(`/${this.lang}`, (req, res, next) => {
+      const {code} = req.body;
+      const tempPath = path.resolve(codesDir, uuid.v4());
+      fs.outputFile(path.resolve(tempPath, `Main.${this.lang}`), code)
+        .then(() => {
+          const containerName = uuid.v4();
+          let killed = false;
+          const timer = setTimeout(() => {
+            execa('docker', ['kill', containerName]).then(() => {
+              killed = true;
+            });
+          }, timeLimit);
+          return execa('docker', [
+            'run', '--rm',
+            `--name=${containerName}`,
+            '-w=/usr/visualization',
+            `-v=${tempPath}:/usr/visualization:rw`,
+            `-m=${memoryLimit}m`,
+            '-e', 'ALGORITHM_VISUALIZER=1',
+            this.imageName,
+          ]).catch(error => {
+            if (killed) throw new Error('Time Limit Exceeded');
+            throw error;
+          }).finally(() => clearTimeout(timer));
+        })
+        .then(() => new Promise((resolve, reject) => {
+          const visualizationPath = path.resolve(tempPath, 'visualization.json');
+          res.sendFile(visualizationPath, (err: any) => {
+            if (err) return reject(new Error('Visualization Not Found'));
+            resolve();
+          });
+        }))
+        .catch(next)
+        .finally(() => fs.remove(tempPath));
+    });
+  }
+}
diff --git a/src/tracers/ImageBuilder.js b/src/tracers/ImageBuilder.js
deleted file mode 100644
index e25d7c1..0000000
--- a/src/tracers/ImageBuilder.js
+++ /dev/null
@@ -1,19 +0,0 @@
-import path from 'path';
-import { execute } from '/common/util';
-
-class ImageBuilder {
-  constructor(lang) {
-    this.lang = lang;
-    this.directory = path.resolve(__dirname, lang);
-    this.imageName = `tracer-${this.lang}`;
-
-    this.build = this.build.bind(this);
-  }
-
-  build(release) {
-    const { tag_name } = release;
-    return execute(`docker build -t ${this.imageName} . --build-arg tag_name=${tag_name}`, { cwd: this.directory });
-  }
-}
-
-export default ImageBuilder;
diff --git a/src/tracers/Tracer.ts b/src/tracers/Tracer.ts
new file mode 100644
index 0000000..400afe2
--- /dev/null
+++ b/src/tracers/Tracer.ts
@@ -0,0 +1,24 @@
+import express from 'express';
+import { GitHubApi } from 'utils/apis';
+
+export type Release = {
+  tag_name: string;
+}
+
+export abstract class Tracer {
+  protected constructor(public lang: string) {
+    this.update().catch(console.error);
+  }
+
+  abstract build(release: Release): Promise<any>;
+
+  abstract route(router: express.Router): void;
+
+  async update(release?: Release) {
+    if (release) {
+      return this.build(release);
+    }
+    const {data} = await GitHubApi.getLatestRelease('algorithm-visualizer', `tracers.${this.lang}`);
+    return this.build(data);
+  }
+}
diff --git a/src/tracers/WorkerBuilder.js b/src/tracers/WorkerBuilder.js
deleted file mode 100644
index 07369cd..0000000
--- a/src/tracers/WorkerBuilder.js
+++ /dev/null
@@ -1,18 +0,0 @@
-import path from 'path';
-import { download } from '/common/util';
-
-class WorkerBuilder {
-  constructor() {
-    this.tracerPath = path.resolve(__dirname, '..', 'public', 'algorithm-visualizer.js');
-    this.workerPath = path.resolve(__dirname, 'js', 'worker.js');
-
-    this.build = this.build.bind(this);
-  }
-
-  build(release) {
-    const { tag_name } = release;
-    return download(`https://github.com/algorithm-visualizer/tracers.js/releases/download/${tag_name}/algorithm-visualizer.js`, this.tracerPath);
-  }
-}
-
-export default WorkerBuilder;
diff --git a/src/tracers/cpp/CppTracer.ts b/src/tracers/cpp/CppTracer.ts
new file mode 100644
index 0000000..a2bc807
--- /dev/null
+++ b/src/tracers/cpp/CppTracer.ts
@@ -0,0 +1,7 @@
+import { DockerTracer } from 'tracers/DockerTracer';
+
+export class CppTracer extends DockerTracer {
+  constructor() {
+    super('cpp');
+  }
+}
diff --git a/src/tracers/index.js b/src/tracers/index.js
deleted file mode 100644
index d41b049..0000000
--- a/src/tracers/index.js
+++ /dev/null
@@ -1,2 +0,0 @@
-export { default as ImageBuilder } from './ImageBuilder';
-export { default as WorkerBuilder } from './WorkerBuilder';
diff --git a/src/tracers/index.ts b/src/tracers/index.ts
new file mode 100644
index 0000000..ae5ad72
--- /dev/null
+++ b/src/tracers/index.ts
@@ -0,0 +1,3 @@
+export { CppTracer } from './cpp/CppTracer';
+export { JavaTracer } from './java/JavaTracer';
+export { JsTracer } from './js/JsTracer';
diff --git a/src/tracers/java/JavaTracer.ts b/src/tracers/java/JavaTracer.ts
new file mode 100644
index 0000000..043c3c6
--- /dev/null
+++ b/src/tracers/java/JavaTracer.ts
@@ -0,0 +1,7 @@
+import { DockerTracer } from 'tracers/DockerTracer';
+
+export class JavaTracer extends DockerTracer {
+  constructor() {
+    super('java');
+  }
+}
diff --git a/src/tracers/js/JsTracer.ts b/src/tracers/js/JsTracer.ts
new file mode 100644
index 0000000..b253a92
--- /dev/null
+++ b/src/tracers/js/JsTracer.ts
@@ -0,0 +1,26 @@
+import path from 'path';
+import { download } from 'utils/misc';
+import { Release, Tracer } from 'tracers/Tracer';
+import express from 'express';
+import { publicDir } from 'config/paths';
+
+export class JsTracer extends Tracer {
+  readonly tracerPath: string;
+  readonly workerPath: string;
+
+  constructor() {
+    super('js');
+    this.tracerPath = path.resolve(publicDir, 'algorithm-visualizer.js');
+    this.workerPath = path.resolve(__dirname, 'worker.js');
+  }
+
+  build(release: Release) {
+    const {tag_name} = release;
+    return download(`https://github.com/algorithm-visualizer/tracers.js/releases/download/${tag_name}/algorithm-visualizer.js`, this.tracerPath);
+  }
+
+  route(router: express.Router) {
+    router.get(`/${this.lang}`, (req, res) => res.sendFile(this.tracerPath));
+    router.get(`/${this.lang}/worker`, (req, res) => res.sendFile(this.workerPath));
+  }
+}
diff --git a/src/utils/apis.ts b/src/utils/apis.ts
new file mode 100644
index 0000000..73355d8
--- /dev/null
+++ b/src/utils/apis.ts
@@ -0,0 +1,61 @@
+import axios, { AxiosResponse } from 'axios';
+import { githubClientId, githubClientSecret } from 'config/environments';
+
+const instance = axios.create();
+
+instance.interceptors.request.use(request => {
+  request.params = {client_id: githubClientId, client_secret: githubClientSecret, ...request.params};
+  return request;
+});
+
+const request = (url: string, process: (mappedUrl: string, args: any[]) => Promise<AxiosResponse<any>>) => {
+  const tokens = url.split('/');
+  const baseURL = /^https?:\/\//i.test(url) ? '' : 'https://api.github.com';
+  return (...args: any[]) => {
+    const mappedUrl = baseURL + tokens.map(token => token.startsWith(':') ? args.shift() : token).join('/');
+    return process(mappedUrl, args);
+  };
+};
+
+const GET = (url: string) => {
+  return request(url, (mappedUrl: string, args: any[]) => {
+    const [params] = args;
+    return instance.get(mappedUrl, {params});
+  });
+};
+
+const DELETE = (url: string) => {
+  return request(url, (mappedUrl: string, args: any[]) => {
+    const [params] = args;
+    return instance.delete(mappedUrl, {params});
+  });
+};
+
+const POST = (url: string) => {
+  return request(url, (mappedUrl: string, args: any[]) => {
+    const [body, params] = args;
+    return instance.post(mappedUrl, body, {params});
+  });
+};
+
+const PUT = (url: string) => {
+  return request(url, (mappedUrl: string, args: any[]) => {
+    const [body, params] = args;
+    return instance.put(mappedUrl, body, {params});
+  });
+};
+
+const PATCH = (url: string) => {
+  return request(url, (mappedUrl: string, args: any[]) => {
+    const [body, params] = args;
+    return instance.patch(mappedUrl, body, {params});
+  });
+};
+
+export const GitHubApi = {
+  listCommits: GET('/repos/:owner/:repo/commits'),
+
+  getAccessToken: (code: string) => instance.post('https://github.com/login/oauth/access_token', {code}, {headers: {Accept: 'application/json'}}),
+
+  getLatestRelease: GET('/repos/:owner/:repo/releases/latest'),
+};
diff --git a/src/utils/hierarchy.ts b/src/utils/hierarchy.ts
new file mode 100644
index 0000000..50baa82
--- /dev/null
+++ b/src/utils/hierarchy.ts
@@ -0,0 +1,18 @@
+import path from 'path';
+import fs from 'fs-extra';
+
+export function createKey(name: string) {
+  return name.toLowerCase().trim().replace(/[^\w \-]/g, '').replace(/ /g, '-');
+}
+
+export function isDirectory(dirPath: string) {
+  return fs.lstatSync(dirPath).isDirectory();
+}
+
+export function listFiles(dirPath: string) {
+  return fs.pathExistsSync(dirPath) ? fs.readdirSync(dirPath).filter(fileName => !fileName.startsWith('.')) : [];
+}
+
+export function listDirectories(dirPath: string) {
+  return listFiles(dirPath).filter(fileName => isDirectory(path.resolve(dirPath, fileName)));
+}
diff --git a/src/utils/misc.ts b/src/utils/misc.ts
new file mode 100644
index 0000000..ed4303e
--- /dev/null
+++ b/src/utils/misc.ts
@@ -0,0 +1,39 @@
+import axios from 'axios';
+import fs from 'fs-extra';
+import execa from 'execa';
+import { File } from 'models';
+import removeMarkdown from 'remove-markdown';
+
+export function download(url: string, localPath: string) {
+  return axios({url, method: 'GET', responseType: 'stream'})
+    .then(response => new Promise((resolve, reject) => {
+      const writer = fs.createWriteStream(localPath);
+      writer.on('finish', resolve);
+      writer.on('error', reject);
+      response.data.pipe(writer);
+    }));
+}
+
+export async function pull(dir: string, repo: string, commit = 'origin/master') {
+  if (fs.pathExistsSync(dir)) {
+    await execa.shell(`git fetch`, {cwd: dir});
+  } else {
+    await execa.shell(`git clone https://github.com/algorithm-visualizer/${repo}.git ${dir}`);
+  }
+  await execa.shell(`git reset --hard ${commit}`, {cwd: dir});
+}
+
+export function getDescription(files: File[]) {
+  const readmeFile = files.find(file => file.name === 'README.md');
+  if (!readmeFile) return '';
+  const lines = readmeFile.content.split('\n');
+  lines.shift();
+  while (lines.length && !lines[0].trim()) lines.shift();
+  let descriptionLines = [];
+  while (lines.length && lines[0].trim()) descriptionLines.push(lines.shift());
+  return removeMarkdown(descriptionLines.join(' '));
+}
+
+export function rethrow(err: any) {
+  throw err;
+}
diff --git a/tsconfig.json b/tsconfig.json
new file mode 100644
index 0000000..eaedd03
--- /dev/null
+++ b/tsconfig.json
@@ -0,0 +1,22 @@
+{
+  "compilerOptions": {
+    "target": "es2015",
+    "lib": [
+      "es2015",
+      "esnext"
+    ],
+    "module": "commonjs",
+    "moduleResolution": "node",
+    "esModuleInterop": true,
+    "experimentalDecorators": true,
+    "emitDecoratorMetadata": true,
+    "sourceMap": true,
+    "declaration": false,
+    "strict": true,
+    "baseUrl": "src",
+    "resolveJsonModule": true
+  },
+  "exclude": [
+    "node_modules",
+  ]
+}
diff --git a/tslint.json b/tslint.json
new file mode 100644
index 0000000..655d091
--- /dev/null
+++ b/tslint.json
@@ -0,0 +1,61 @@
+{
+  "rules": {
+    "class-name": true,
+    "comment-format": [
+      true,
+      "check-space"
+    ],
+    "indent": [
+      true,
+      "spaces",
+      2
+    ],
+    "one-line": [
+      true,
+      "check-open-brace",
+      "check-whitespace"
+    ],
+    "no-var-keyword": true,
+    "quotemark": [
+      true,
+      "single",
+      "avoid-escape"
+    ],
+    "semicolon": [
+      true,
+      "always",
+      "ignore-bound-class-methods"
+    ],
+    "whitespace": [
+      true,
+      "check-branch",
+      "check-decl",
+      "check-operator",
+      "check-module",
+      "check-separator",
+      "check-type"
+    ],
+    "typedef-whitespace": [
+      true,
+      {
+        "call-signature": "nospace",
+        "index-signature": "nospace",
+        "parameter": "nospace",
+        "property-declaration": "nospace",
+        "variable-declaration": "nospace"
+      },
+      {
+        "call-signature": "onespace",
+        "index-signature": "onespace",
+        "parameter": "onespace",
+        "property-declaration": "onespace",
+        "variable-declaration": "onespace"
+      }
+    ],
+    "no-internal-module": true,
+    "no-trailing-whitespace": true,
+    "no-null-keyword": true,
+    "prefer-const": true,
+    "jsdoc-format": true
+  }
+}
diff --git a/webpack.backend.config.js b/webpack.backend.config.js
deleted file mode 100644
index 5185c70..0000000
--- a/webpack.backend.config.js
+++ /dev/null
@@ -1,45 +0,0 @@
-const CleanWebpackPlugin = require('clean-webpack-plugin');
-const nodeExternals = require('webpack-node-externals');
-const path = require('path');
-const fs = require('fs');
-
-const {
-  __DEV__,
-  backendBuildPath: buildPath,
-  backendSrcPath: srcPath,
-} = require('./environment');
-
-const alias = {
-  '/environment': path.resolve(__dirname, 'environment.js'),
-};
-fs.readdirSync(srcPath).forEach(name => {
-  alias['/' + name] = path.resolve(srcPath, name);
-});
-
-module.exports = {
-  target: 'node',
-  node: {
-    __dirname: true,
-  },
-  entry: srcPath,
-  externals: [nodeExternals()],
-  resolve: {
-    modules: [srcPath],
-    extensions: ['.js'],
-    alias,
-  },
-  output: {
-    path: buildPath,
-    filename: 'index.js',
-    libraryTarget: 'umd',
-  },
-  module: {
-    rules: [
-      { test: /\.js$/, use: 'babel-loader', include: srcPath },
-    ],
-  },
-  plugins: [
-    new CleanWebpackPlugin([buildPath]),
-  ],
-  mode: __DEV__ ? 'development' : 'production',
-};
\ No newline at end of file