diff --git a/Gemfile b/Gemfile
index 7859791..9136cc7 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,87 +1,59 @@
 source 'https://rubygems.org'
 
-
-# Bundle edge Rails instead: gem 'rails', github: 'rails/rails'
 gem 'rails', '~> 5.1.5'
 gem 'rails-i18n'
-# Use sqlite3 as the database for Active Record
+
+# database and search index
+gem 'elasticsearch', '~> 6'
+gem 'elasticsearch-dsl'
+gem 'elasticsearch-model', '~> 6'
+gem 'elasticsearch-rails', '~> 6'
 gem 'sqlite3'
+
+# pagination
 gem 'kaminari'
 gem 'kaminari-i18n'
-# Use SCSS for stylesheets
-gem 'sass-rails'
-# Use Uglifier as compressor for JavaScript assets
-gem 'uglifier'
-# Use CoffeeScript for .js.coffee assets and views
-gem 'coffee-rails'
-# See https://github.com/sstephenson/execjs#readme for more supported runtimes
-# gem 'therubyracer',  platforms: :ruby
-gem 'slim-rails'
-# Use jquery as the JavaScript library
-gem 'jquery-rails'
-# Turbolinks makes following links in your web application faster. Read more: https://github.com/rails/turbolinks
-gem 'turbolinks'
-# Assets
-gem 'foundation-rails', '~> 5.5'
 
-gem 'validate_url'
-
-# Authentication
+# authentication
 gem 'omniauth'
 gem 'omniauth-browserid'
 
-gem 'elasticsearch', '~> 6'
-gem 'elasticsearch-model', '~> 6'
-gem 'elasticsearch-rails', '~> 6'
-gem 'elasticsearch-dsl'
+# templates, css and other frontend related
+gem 'foundation-rails', '~> 5.5'
+gem 'jquery-rails'
+gem 'sass-rails'
+gem 'slim-rails'
+gem 'turbolinks'
+gem 'uglifier'
 
+# misc
 gem 'leaflet-rails'
-
-gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw]
-
-# bundle exec rake doc:rails generates the API under doc/api.
-gem 'sdoc', '~> 0.4.0',          group: :doc
+gem 'validate_url'
 
 group :development do
+  gem 'awesome_print'
   gem 'spring'
   gem 'spring-commands-rspec'
-  # https://rossta.net/blog/quiet-assets-in-rails-5.html
-  # gem 'quiet_assets'
-  gem 'awesome_print'
-  # gem 'guard-rspec', require: false
-  # gem 'terminal-notifier-guard' # FIXME cross-platform
 end
 
 group :development, :test do
-  gem 'rspec-rails', '~> 3.0'
+  gem 'capybara'
+  gem 'launchy'
   gem 'pry'
   gem 'pry-rails'
-  gem 'capybara'
   gem 'puma'
-  gem 'launchy'
+  gem 'rspec-rails', '~> 3.0'
   gem 'rubocop'
 end
 
 group :test do
-  gem "factory_bot_rails"
-  gem 'shoulda-matchers', '~> 3.1'
-  gem 'faker'
-  gem 'rubocop-faker'
-  gem 'simplecov', require: false
-  gem 'database_cleaner'
-  gem 'coveralls', require: false
   gem 'apparition'
+  gem 'coveralls', require: false
+  gem 'database_cleaner'
+  gem 'factory_bot_rails'
+  gem 'faker'
   gem 'rails-controller-testing'
+  gem 'rubocop-faker'
+  gem 'shoulda-matchers', '~> 3.1'
+  gem 'simplecov', require: false
 end
-
-# Use ActiveModel has_secure_password
-# gem 'bcrypt', '~> 3.1.7'
-
-# Use unicorn as the app server
-# gem 'unicorn'
-
-# Use Capistrano for deployment
-# gem 'capistrano-rails', group: :development
-
-# Use debugger
-# gem 'debugger', group: [:development, :test]
diff --git a/Gemfile.lock b/Gemfile.lock
index 2149d94..1636b97 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -56,13 +56,6 @@ GEM
       regexp_parser (~> 1.5)
       xpath (~> 3.2)
     coderay (1.1.2)
-    coffee-rails (4.2.2)
-      coffee-script (>= 2.2.0)
-      railties (>= 4.0.0)
-    coffee-script (2.4.1)
-      coffee-script-source
-      execjs
-    coffee-script-source (1.12.2)
     concurrent-ruby (1.1.6)
     coveralls (0.7.2)
       multi_json (~> 1.3)
@@ -113,7 +106,6 @@ GEM
       rails-dom-testing (>= 1, < 3)
       railties (>= 4.2.0)
       thor (>= 0.14, < 2.0)
-    json (1.8.6)
     kaminari (1.2.0)
       activesupport (>= 4.1.0)
       kaminari-actionview (= 1.2.0)
@@ -203,7 +195,6 @@ GEM
       thor (>= 0.18.1, < 2.0)
     rainbow (3.0.0)
     rake (13.0.1)
-    rdoc (4.3.0)
     regexp_parser (1.7.0)
     rest-client (1.6.7)
       mime-types (>= 1.16)
@@ -247,9 +238,6 @@ GEM
       sprockets (> 3.0)
       sprockets-rails
       tilt
-    sdoc (0.4.2)
-      json (~> 1.7, >= 1.7.7)
-      rdoc (~> 4.0)
     shoulda-matchers (3.1.3)
       activesupport (>= 4.0.0)
     simplecov (0.18.5)
@@ -305,7 +293,6 @@ DEPENDENCIES
   apparition
   awesome_print
   capybara
-  coffee-rails
   coveralls
   database_cleaner
   elasticsearch (~> 6)
@@ -332,7 +319,6 @@ DEPENDENCIES
   rubocop
   rubocop-faker
   sass-rails
-  sdoc (~> 0.4.0)
   shoulda-matchers (~> 3.1)
   simplecov
   slim-rails
@@ -340,7 +326,6 @@ DEPENDENCIES
   spring-commands-rspec
   sqlite3
   turbolinks
-  tzinfo-data
   uglifier
   validate_url
 
diff --git a/app/assets/javascripts/sessions.js.coffee b/app/assets/javascripts/sessions.js.coffee
deleted file mode 100644
index 24f83d1..0000000
--- a/app/assets/javascripts/sessions.js.coffee
+++ /dev/null
@@ -1,3 +0,0 @@
-# Place all the behaviors and hooks related to the matching controller here.
-# All this logic will automatically be available in application.js.
-# You can use CoffeeScript in this file: http://coffeescript.org/