diff --git a/assets/javascripts/templates/pages/about_tmpl.coffee b/assets/javascripts/templates/pages/about_tmpl.coffee
index b066c0ab..46001979 100644
--- a/assets/javascripts/templates/pages/about_tmpl.coffee
+++ b/assets/javascripts/templates/pages/about_tmpl.coffee
@@ -262,6 +262,11 @@ credits = [
     '2001-2015 by the original authors<br>Drupal is a registered trademark of Dries Buytaert.',
     'GPLv2',
     'https://api.drupal.org/api/drupal/LICENSE.txt'
+  ],[
+    'Eigen3',
+    'Eigen',
+    'MPL2',
+    'https://www.mozilla.org/en-US/MPL/2.0/'
   ], [
     'Electron',
     'GitHub Inc.',
diff --git a/assets/stylesheets/application.css.scss b/assets/stylesheets/application.css.scss
index 3a6d428e..1d5da325 100644
--- a/assets/stylesheets/application.css.scss
+++ b/assets/stylesheets/application.css.scss
@@ -52,6 +52,7 @@
         'pages/dart',
         'pages/dojo',
         'pages/drupal',
+        'pages/eigen3',
         'pages/elixir',
         'pages/elisp',
         'pages/ember',
diff --git a/assets/stylesheets/pages/_eigen3.scss b/assets/stylesheets/pages/_eigen3.scss
new file mode 100644
index 00000000..e69de29b
diff --git a/lib/docs/filters/eigen3/clean_html.rb b/lib/docs/filters/eigen3/clean_html.rb
new file mode 100644
index 00000000..3870566e
--- /dev/null
+++ b/lib/docs/filters/eigen3/clean_html.rb
@@ -0,0 +1,25 @@
+module Docs
+  class Eigen3
+    class CleanHtmlFilter < Filter
+
+      def call
+        @doc = at_css('#doc-content')
+        css('#MSearchSelectWindow').remove
+        css('#MSearchResultsWindow').remove
+        css('.directory .levels').remove
+        css('.header .summary').remove
+        css('.ttc').remove
+        css('.top').remove
+        css('.dynheader.closed').remove
+        css('.permalink').remove
+        css('.groupheader').remove
+        css('.header').remove
+        css('#details').remove
+        css('*').each do |node|
+          node.remove_attribute('class')
+        end
+        doc
+      end
+    end
+  end
+end
diff --git a/lib/docs/filters/eigen3/entries.rb b/lib/docs/filters/eigen3/entries.rb
new file mode 100644
index 00000000..b80b0e24
--- /dev/null
+++ b/lib/docs/filters/eigen3/entries.rb
@@ -0,0 +1,123 @@
+module Docs
+  class Eigen3
+    class EntriesFilter < Docs::EntriesFilter
+      def get_type
+        group = at_css('.title .ingroups')
+        content = at_css('.contents').content
+        title = get_title()
+        downtitle = title.downcase
+        name = get_name
+
+        if slug.include?('unsupported')
+          return 'Unsupported'
+        elsif slug.start_with?('Topic') || downtitle.end_with?("topics")
+            return 'Topics'
+        elsif downtitle.end_with?("class template reference") || downtitle.end_with?("class reference")
+          return 'Classes'
+        elsif downtitle.end_with?("struct reference")
+          return 'Structs'
+        elsif downtitle.end_with?("typedefs")
+          return 'Typedefs'
+        elsif downtitle.end_with?("namespace reference")
+            return 'Namespaces'
+        elsif not group.nil? and group.content.include?('Reference') and (downtitle.end_with?("module") || downtitle.end_with?("modules"))
+            return "Modules"
+        elsif not group.nil?
+          if group.children.length > 0
+            return 'Chapter: ' + group.children[-1].content
+          else
+            return 'Chapter: ' + group.content
+          end
+        else
+          return 'Eigen'
+        end
+      end
+
+      def get_name
+        title = get_title().gsub(/[<(].*/, '').gsub(/(Class|Class Template|Namespace|Struct) Reference/, '').strip
+      end
+
+      def get_title
+        unless at_css('.title').nil?
+          group = at_css('.title .ingroups')
+          title = at_css('.title').content
+          if not group.nil?
+            title = title.delete_suffix(group.content)
+          end
+          return title.strip
+        else
+          return slug
+        end
+      end
+
+
+      def additional_entries
+        # return [] if slug.include?('unsupported')
+        name = get_name()
+        entries = []
+
+        css('table.memberdecls').map do |table|
+          doxygen_type = table.at_css("tr.heading").text.strip
+          case doxygen_type
+          when "Functions"
+            type = "Functions"
+          when "Public Member Functions", "Static Public Member Functions", "Public Types", "Additional Inherited Members"
+            type = nil
+          when "Classes"
+            type = "Classes"
+          when "Typedefs"
+            type = "Typedefs"
+          when "Variables"
+            type = "Variables"
+          else
+            next
+          end
+
+          tmp_entries = []
+
+          table.css('td.memItemRight,td.memTemplItemRight').map do |node_r|
+            node_l = node_r.parent.at_css('memItemLeft')
+            if (not node_l.nil? and node_l.text.strip == 'enum') || node_r.content.include?('{')
+              node_r.css("a").each {|n| tmp_entries << [n.content, n.attr('href')]}
+            else
+              n = node_r.at_css("a")
+              next if n.nil?
+              tmp_entries << [node_r.content, n.attr('href')]
+            end
+          end
+
+          tmp_entries.each do |args|
+            (content, href) = args
+            next if href.nil?
+            if not href.include?("#") and (name == 'Eigen' || type == "Classes") then
+              next
+            end
+
+            if slug.include?('unsupported')
+              if not (href.include?('unsupported') || href.include?('#'))
+                next
+              elsif href.include?('#') and not href.include?('unsupported')
+                href = 'unsupported/' + href
+              end
+            end
+
+            if doxygen_type == "Typedefs"
+              content = content.sub(/\s*=.*$/, "")
+            end
+
+            if not (name.end_with?('module') || name.end_with?('typedefs')) \
+              and not content.start_with?("Eigen::")
+              content = name + "::" + content
+            end
+            content.gsub! /^\s+/, ''
+            content.gsub! /\s+,\s+/, ', '
+            content.gsub! /\s\s+/, ' '
+            entries << [content, href, type]
+          end
+
+        end
+        entries
+      end
+    end
+  end
+end
diff --git a/lib/docs/scrapers/eigen3.rb b/lib/docs/scrapers/eigen3.rb
new file mode 100644
index 00000000..7ed3d1eb
--- /dev/null
+++ b/lib/docs/scrapers/eigen3.rb
@@ -0,0 +1,76 @@
+module Docs
+  class Eigen3 < UrlScraper
+    self.name = 'Eigen3'
+    self.type = 'eigen3'
+    self.slug = 'eigen3'
+    self.base_url = 'https://eigen.tuxfamily.org/dox/'
+    self.root_path = 'index.html'
+    self.initial_paths = [
+      "modules.html"
+    ]
+    self.release = '3.4.0'
+
+    self.links = {
+      home: 'https://eigen.tuxfamily.org',
+      code: 'https://gitlab.com/libeigen/eigen'
+    }
+
+    html_filters.push 'eigen3/entries', 'eigen3/clean_html', 'title'
+
+    # Remove the `clean_text` because Doxygen are actually creating empty
+    # anchor such as <a id="asd"></a> to do anchor link.. and that anchor
+    # will be removed by clean_text
+    self.text_filters = FilterStack.new
+    text_filters.push 'images', 'inner_html', 'attribution'
+
+
+
+    def get_latest_version(opts)
+      tags = get_gitlab_tags("https://gitlab.com", "libeigen", "eigen", opts)
+      tags[0]['name']
+    end
+
+    options[:attribution] = <<-HTML
+      &copy; Eigen.<br>
+      Licensed under the MPL2 License.
+    HTML
+
+    # Skip source code since it doesn't provide any useful docs
+    options[:skip_patterns] = [/_source/, /-members/, /__Reference\.html/, /_chapter\.html/, /\.txt/, /\.tgz/]
+
+    # TODO: replace cppreference
+    # options[:replace_urls] = { 'http://en.cppreference.com/w/cpp/' => 'cpp/' }
+
+    def parse(response) # Hook here because Nokogori removes whitespace from code fragments
+      last_idx = 0
+      # Process nested <div>s inside code fragment div.
+      while not (last_idx = response.body.index('<div class="fragment">', last_idx)).nil?
+        # enter code fragment <div>
+        level = 1
+        while not (last_idx = response.body.index(/<\/?div/, last_idx+1)).nil?
+          # skip nested divs inside.
+          if response.body[last_idx..last_idx+3] == '<div'
+            level += 1
+          else
+            level -= 1
+          end
+          break if level == 0 # exit code fragment
+        end
+        if not last_idx.nil? and response.body[last_idx..last_idx+5] == '</div>'
+          response.body[last_idx..last_idx+5] = '</pre>'
+        end
+      end
+      response.body.gsub! /[\r\n\s]*<div class="ttc"[^>]*>.*<\/div>[\r\n\s]*/, ""
+      response.body.gsub! /<div class="line">(.*?)<\/div>/m, "\\1"
+      response.body.gsub! '<div class="fragment">', '<pre class="fragment" data-language="cpp">'
+      super
+    end
+
+    def process_response?(response)
+      return false unless super
+      # Remove Empty pages.
+      response.body.index(/<div class="contents">[\r\n\s]*<\/div>/m).nil? and \
+        response.body.index(/<p>TODO: write this dox page!<\/p>/).nil?
+    end
+  end
+end
diff --git a/public/icons/docs/eigen3/16.png b/public/icons/docs/eigen3/16.png
new file mode 100644
index 00000000..265a2f49
Binary files /dev/null and b/public/icons/docs/eigen3/16.png differ
diff --git a/public/icons/docs/eigen3/16@2x.png b/public/icons/docs/eigen3/16@2x.png
new file mode 100644
index 00000000..9cc98d2c
Binary files /dev/null and b/public/icons/docs/eigen3/16@2x.png differ
diff --git a/public/icons/docs/eigen3/SOURCE b/public/icons/docs/eigen3/SOURCE
new file mode 100644
index 00000000..439adb72
--- /dev/null
+++ b/public/icons/docs/eigen3/SOURCE
@@ -0,0 +1 @@
+https://gitlab.com/libeigen/eigen/-/blob/master/doc/Eigen_Silly_Professor_64x64.png