diff --git a/docs/js/extra.js b/docs/js/extra.js
new file mode 100644
index 00000000000..a0224705a88
--- /dev/null
+++ b/docs/js/extra.js
@@ -0,0 +1,219 @@
+var nodemcu = nodemcu || {};
+(function () {
+  'use strict';
+  //var languageCodeToNameMap = {en: 'English', de: 'Deutsch'};
+  var languageCodeToNameMap = {en: 'English'};
+  var languageNames = values(languageCodeToNameMap);
+  var defaultLanguageCode = 'en';
+
+  $(document).ready(function () {
+    addToc();
+    fixSearch();
+    hideNavigationForAllButSelectedLanguage();
+    addLanguageSelectorToRtdFlyOutMenu();
+    replaceRelativeLinksWithStaticGitHubUrl();
+  });
+
+  /**
+   * Adds a TOC-style table to each page in the 'Modules' section.
+   */
+  function addToc() {
+    var func, intro, tocHtmlTable;
+    if (isModulePage()) {
+      tocHtmlTable = '<table class="docutils">';
+      $('h2').each(function (index) {
+        // 'slice' cuts off the single permalink character at the end of the text (e.g. '¶')
+        func = $(this).text().slice(0, -1);
+        // get the first sentence of the paragraph directly below h2
+        intro = $(this).next().text();
+        intro = intro.substring(0, intro.indexOf('.') + 1);
+        tocHtmlTable += createTocTableRow(func, intro);
+      });
+      tocHtmlTable += '</table>';
+      $(tocHtmlTable).insertBefore($('h2').first())
+    }
+    function isModulePage() {
+      // if the breadcrumb contains 'Modules »' it must be an API page
+      return $("ul.wy-breadcrumbs li:contains('Modules »')").size() > 0;
+    }
+    function createTocTableRow(func, intro) {
+      // fragile attempt to auto-create the in-page anchor
+      var href = func.replace(/\.|:/g, '').replace('()', '').replace(' --', '-').replace(/ /g, '-');
+      var link = '<a href="#' + href.toLowerCase() + '">' + func + '</a>';
+      return '<tr><td>' + link + '</td><td>' + intro + '</td></tr>';
+    }
+  }
+
+  /*
+   * RTD messes up MkDocs' search feature by tinkering with the search box defined in the theme, see
+   * https://github.com/rtfd/readthedocs.org/issues/1088. This function sets up a DOM4 MutationObserver
+   * to react to changes to the search form (triggered by RTD on doc ready). It then reverts everything
+   * the RTD JS code modified.
+   */
+  function fixSearch() {
+    var target = document.getElementById('rtd-search-form');
+    var config = {attributes: true, childList: true};
+
+    var observer = new MutationObserver(function(mutations) {
+      // if it isn't disconnected it'll loop infinitely because the observed element is modified
+      observer.disconnect();
+      var form = $('#rtd-search-form');
+      form.empty();
+      form.attr('action', 'https://' + window.location.hostname + '/en/' + determineSelectedBranch() + '/search.html');
+      $('<input>').attr({
+        type: "text",
+        name: "q",
+        placeholder: "Search docs"
+      }).appendTo(form);
+    });
+
+    if (window.location.origin.indexOf('readthedocs') > -1) {
+      observer.observe(target, config);
+    }
+  }
+
+  function hideNavigationForAllButSelectedLanguage() {
+    var selectedLanguageCode = determineSelectedLanguageCode();
+    var selectedLanguageName = languageCodeToNameMap[selectedLanguageCode];
+    // Finds all subnav elements and hides them if they're /language/ subnavs. Hence, all 'Modules' subnav elements
+    // won't be hidden.
+    // <ul class="subnav">
+    //   <li><span>Modules</span></li>
+    //   <li class="toctree-l1 ">
+    //     <a class="" href="EN/modules/node/">node</a>
+    //   </li>
+    $('.subnav li span').not(':contains(' + selectedLanguageName + ')').each(function (index) {
+      var spanElement = $(this);
+      if ($.inArray(spanElement.text(), languageNames) > -1) {
+        spanElement.parent().parent().hide();
+      }
+    });
+  }
+
+  /**
+   * Adds a language selector to the RTD fly-out menu found bottom left. Example:
+   *
+   * <dl>
+   *   <dt>Languages</dt>
+   *   <dd><a href="http://nodemcu.readthedocs.io/en/<branch>/de/">de</a></dd>
+   *   <strong>
+   *     <dd><a href="http://nodemcu.readthedocs.io/en/<branch>/en/">en</a></dd>
+   *   </strong>
+   * </dl>
+   *
+   * UGLY! That fly-out menu is added by RTD with an AJAX call after page load. Hence, we need to
+   * react to the subsequent DOM manipulation using a DOM4 MutationObserver. The provided structure
+   * is as follows:
+   *
+   * <div class="rst-other-versions">
+   *   <!-- Inserted RTD Footer -->
+   *   <div class="injected">
+   */
+  function addLanguageSelectorToRtdFlyOutMenu() {
+    var flyOutWrapper = $('.rst-other-versions');
+    // only relevant on RTD
+    if (flyOutWrapper.size() > 0) {
+      var observer = new MutationObserver(function (mutations) {
+        // since mutation on the target node was triggered we can safely assume the injected RTD div has now been added
+        var injectedDiv = $('.rst-other-versions .injected');
+        var selectedLanguageCode = determineSelectedLanguageCode();
+        var dl = document.createElement('dl');
+        var dt = document.createElement('dt');
+        dl.appendChild(dt);
+        dt.appendChild(document.createTextNode('Languages'));
+        for (var languageCode in languageCodeToNameMap) {
+          dl.appendChild(createLanguageLinkFor(languageCode, selectedLanguageCode === languageCode));
+        }
+        injectedDiv.prepend(dl);
+        // no need for that observer anymore
+        observer.disconnect();
+      });
+
+      // observed target node is the fly-out wrapper, the only event we care about is when children are modified
+      observer.observe(flyOutWrapper[0], {childList: true});
+    }
+  }
+
+  /**
+   * The module doc pages contain relative links to artifacts in the GitHub repository. For those links to work both
+   * on GitHub (i.e. when the page is viewed on GitHub) and on RTD they are defined with a relative URL. This function
+   * replaces the relative path with an absolute path based on the selected branch.
+   */
+  function replaceRelativeLinksWithStaticGitHubUrl() {
+    var relativePath = "../../../..";
+    var gitHubPath = "https://github.com/nodemcu/nodemcu-firmware/tree/" + determineSelectedBranch();
+    var gitHubLinks = $("a[href^='" + relativePath + "']").each(function (index) {
+      var url = $(this).attr('href');
+      $(this).attr('href', url.replace(relativePath, gitHubPath));
+    });
+  }
+
+  function createLanguageLinkFor(languageCode, isCurrentlySelected) {
+    var strong;
+    // split[0] is an '' because the path starts with the separator
+    var pathSegments = window.location.pathname.split('/');
+    var dd = document.createElement("dd");
+    var href = document.createElement("a");
+    href.setAttribute('href', '/' + pathSegments[1] + '/' + pathSegments[2] + '/' + languageCode);
+    href.appendChild(document.createTextNode(languageCode));
+    dd.appendChild(href);
+    if (isCurrentlySelected) {
+      strong = document.createElement("strong");
+      strong.appendChild(dd);
+      return strong;
+    } else {
+      return dd;
+    }
+  }
+
+  /**
+   * Analyzes the URL of the current page to find out what the selected language is. It's usually
+   * part of the location path. The code needs to distinguish between running MkDocs standalone
+   * and docs served from RTD. If no valid language could be determined the default language is
+   * returned.
+   *
+   * @returns 2-char language code
+   */
+  function determineSelectedLanguageCode() {
+    var selectedLanguageCode, path = window.location.pathname;
+    if (window.location.origin.indexOf('readthedocs') > -1) {
+      // path is like /en/<branch>/<lang>/build/ -> extract 'lang'
+      // split[0] is an '' because the path starts with the separator
+      selectedLanguageCode = path.split('/')[3];
+    } else {
+      // path is like /<lang>/build/ -> extract 'lang'
+      selectedLanguageCode = path.substr(1, 2);
+    }
+    if (!selectedLanguageCode || selectedLanguageCode.length > 2) {
+      selectedLanguageCode = defaultLanguageCode;
+    }
+    return selectedLanguageCode;
+  }
+
+  /**
+   * Analyzes the URL of the current page to find out what the selected GitHub branch is. It's usually
+   * part of the location path. The code needs to distinguish between running MkDocs standalone
+   * and docs served from RTD. If no valid branch could be determined 'dev' returned.
+   *
+   * @returns GitHub branch name
+   */
+  function determineSelectedBranch() {
+    var branch = 'dev', path = window.location.pathname;
+    if (window.location.origin.indexOf('readthedocs') > -1) {
+      // path is like /en/<branch>/<lang>/build/ -> extract 'lang'
+      // split[0] is an '' because the path starts with the separator
+      branch = path.split('/')[2];
+    }
+    return branch;
+  }
+
+  function values(associativeArray) {
+    var values = [];
+    for (var key in associativeArray) {
+      if (associativeArray.hasOwnProperty(key)) {
+        values.push(associativeArray[key]);
+      }
+    }
+    return values;
+  }
+}());
diff --git a/mkdocs.yml b/mkdocs.yml
index e11c3d9056b..b46a2e326d0 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -60,6 +60,8 @@ theme: readthedocs
 
 extra_css:
     - css/extra.css
+extra_javascript:
+    - js/extra.js
 
 copyright: Copyright &copy; 2017 <a href="https://broadinstitute.org">Broad Institute</a>
 # google_analytics: ['identifierID', 'URL.org']