diff --git a/Gemfile b/Gemfile
index c0d04304..dcf6d696 100644
--- a/Gemfile
+++ b/Gemfile
@@ -18,8 +18,7 @@ gem 'jquery-rails'
 gem 'haml-rails'
 gem 'gravatar_image_tag'
 gem 'paperclip'
-gem 'formtastic', '~> 3.1'
-gem 'formtastic-bootstrap'
+gem 'simple_form'
 gem 'favicon_maker'
 gem 'mini_magick'
 gem 'puma'
diff --git a/Gemfile.lock b/Gemfile.lock
index dfbcc6bc..a8982f58 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -96,10 +96,6 @@ GEM
     favicon_maker (1.3.1)
       docile (~> 1.1)
     ffi (1.15.0)
-    formtastic (3.1.5)
-      actionpack (>= 3.2.13)
-    formtastic-bootstrap (3.1.1)
-      formtastic (>= 3.0)
     git_rev (0.1.0)
     globalid (0.4.2)
       activesupport (>= 4.2.0)
@@ -208,6 +204,9 @@ GEM
     sentry-raven (3.1.1)
       faraday (>= 1.0)
     sexp_processor (4.15.2)
+    simple_form (5.1.0)
+      actionpack (>= 5.2)
+      activemodel (>= 5.2)
     simplecov (0.13.0)
       docile (~> 1.1.0)
       json (>= 1.8, < 3)
@@ -248,8 +247,6 @@ DEPENDENCIES
   coffee-rails
   faker
   favicon_maker
-  formtastic (~> 3.1)
-  formtastic-bootstrap
   git_rev
   gravatar_image_tag
   haml-rails
@@ -265,6 +262,7 @@ DEPENDENCIES
   ruby-prof
   sassc-rails
   sentry-raven
+  simple_form
   spring
   sqlite3
   uglifier
diff --git a/app/assets/stylesheets/application.css.scss b/app/assets/stylesheets/application.css.scss
index f89ddf32..13d7ad74 100644
--- a/app/assets/stylesheets/application.css.scss
+++ b/app/assets/stylesheets/application.css.scss
@@ -1,6 +1,5 @@
 @import "bootswatch/slate/variables";
 @import "bootstrap";
-@import "formtastic-bootstrap";
 @import "bootswatch/slate/bootswatch";
 
 // make room for navigation bar
diff --git a/app/views/barcodes/_form.html.haml b/app/views/barcodes/_form.html.haml
index 8946a302..983b6c7f 100644
--- a/app/views/barcodes/_form.html.haml
+++ b/app/views/barcodes/_form.html.haml
@@ -1,7 +1,7 @@
-= semantic_form_for @barcode, :html => { :class => 'form-horizontal' } do |f|
-  = f.semantic_errors
-  = f.inputs do
+= simple_form_for @barcode, :html => { :class => 'form-horizontal' } do |f|
+  = f.error_notification
+  .form-inputs
     = f.input :id, hint: 'the label says…', input_html: { :autofocus => true }
     = f.input :drink, hint: 'If you edit a drink and click on "add barcode" this will be prefilled for you.', as: "select", collection: @drinks
-  = f.actions do
-    = f.action :submit
+  .form-actions
+    = f.button :submit, class: 'btn-primary'
diff --git a/app/views/drinks/_form.html.haml b/app/views/drinks/_form.html.haml
index 537c18a0..506e826f 100644
--- a/app/views/drinks/_form.html.haml
+++ b/app/views/drinks/_form.html.haml
@@ -2,15 +2,15 @@
   %li
     = link_to 'delete drink', @drink, method: :delete, :data => {confirm: "Really delete drink #{@drink.name}?"}
 
-= semantic_form_for @drink, :html => { :class => 'form-horizontal' } do |f|
-  = f.semantic_errors
-  = f.inputs  do
+= simple_form_for @drink, :html => { :class => 'form-horizontal' } do |f|
+  = f.error_notification
+  .form-inputs
     = f.input :name, hint:'the label says…'
-    = f.input :price, as: :number, hint:'e.g. 1.50; locked due to vandalism', :input_html => { :disabled => true }
+    = f.input :price, as: :decimal, hint:'e.g. 1.50; locked due to vandalism', :input_html => { :disabled => true }
     = f.input :bottle_size, hint: '0.5 or 0.33?'
     = f.input :caffeine, hint: 'in mg/100 ml'
     = f.input :logo, hint: 'make it look pretty'
     = f.input :active
-  = f.actions do
-    = f.action :submit
+  .form-actions
+    = f.button :submit, class: 'btn-primary'
     = link_to 'Add a barcode', new_barcode_path(:drink => @drink.id), :class => 'btn'
diff --git a/app/views/users/_form.html.haml b/app/views/users/_form.html.haml
index 4c4716b5..787b0d11 100644
--- a/app/views/users/_form.html.haml
+++ b/app/views/users/_form.html.haml
@@ -1,13 +1,13 @@
-= semantic_form_for @user, :html => { :class => 'form-horizontal' } do |f|
-  = f.semantic_errors
-  = f.inputs do
+= simple_form_for @user, :html => { :class => 'form-horizontal' } do |f|
+  = f.error_notification
+  .form-inputs
     = f.input :name, hint: 'your nickname'
     = f.input :email, hint: 'your eMail address. Only used to fetch your avatar from gravatar.com.'
-    = f.input :balance, :as => :number, hint: 'just in case you need to correct this'
+    = f.input :balance, :as => :decimal, hint: 'just in case you need to correct this'
     = f.input :active
     = f.input :audit, hint: 'This will create detailed logs about what you buy and deposit. If you uncheck this box, all records will be deleted.'
     = f.input :redirect, hint: "Redirect after buying a drink?"
-  = f.actions do
-    = f.action :submit
+  .form-actions
+    = f.button :submit, class: 'btn-primary'
 
 %style .user { display: initial!important; }
diff --git a/config/initializers/formtastic.rb b/config/initializers/formtastic.rb
deleted file mode 100644
index f281ba8b..00000000
--- a/config/initializers/formtastic.rb
+++ /dev/null
@@ -1,76 +0,0 @@
-# encoding: utf-8
-
-# Set the default text field size when input is a string. Default is nil.
-# Formtastic::FormBuilder.default_text_field_size = 50
-
-# Set the default text area height when input is a text. Default is 20.
-# Formtastic::FormBuilder.default_text_area_height = 5
-
-# Set the default text area width when input is a text. Default is nil.
-# Formtastic::FormBuilder.default_text_area_width = 50
-
-# Should all fields be considered "required" by default?
-# Defaults to true.
-# Formtastic::FormBuilder.all_fields_required_by_default = true
-
-# Should select fields have a blank option/prompt by default?
-# Defaults to true.
-# Formtastic::FormBuilder.include_blank_for_select_by_default = true
-
-# Set the string that will be appended to the labels/fieldsets which are required
-# It accepts string or procs and the default is a localized version of
-# '<abbr title="required">*</abbr>'. In other words, if you configure formtastic.required
-# in your locale, it will replace the abbr title properly. But if you don't want to use
-# abbr tag, you can simply give a string as below
-# Formtastic::FormBuilder.required_string = "(required)"
-
-# Set the string that will be appended to the labels/fieldsets which are optional
-# Defaults to an empty string ("") and also accepts procs (see required_string above)
-# Formtastic::FormBuilder.optional_string = "(optional)"
-
-# Set the way inline errors will be displayed.
-# Defaults to :sentence, valid options are :sentence, :list, :first and :none
-# Formtastic::FormBuilder.inline_errors = :sentence
-# Formtastic uses the following classes as default for hints, inline_errors and error list
-
-# If you override the class here, please ensure to override it in your stylesheets as well
-# Formtastic::FormBuilder.default_hint_class = "inline-hints"
-# Formtastic::FormBuilder.default_inline_error_class = "inline-errors"
-# Formtastic::FormBuilder.default_error_list_class = "errors"
-
-# Set the method to call on label text to transform or format it for human-friendly
-# reading when formtastic is used without object. Defaults to :humanize.
-# Formtastic::FormBuilder.label_str_method = :humanize
-
-# Set the array of methods to try calling on parent objects in :select and :radio inputs
-# for the text inside each @<option>@ tag or alongside each radio @<input>@. The first method
-# that is found on the object will be used.
-# Defaults to ["to_label", "display_name", "full_name", "name", "title", "username", "login", "value", "to_s"]
-# Formtastic::FormBuilder.collection_label_methods = [
-#   "to_label", "display_name", "full_name", "name", "title", "username", "login", "value", "to_s"]
-
-# Specifies if labels/hints for input fields automatically be looked up using I18n.
-# Default value: true. Overridden for specific fields by setting value to true,
-# i.e. :label => true, or :hint => true (or opposite depending on initialized value)
-# Formtastic::FormBuilder.i18n_lookups_by_default = false
-
-# Specifies if I18n lookups of the default I18n Localizer should be cached to improve performance.
-# Defaults to true.
-# Formtastic::FormBuilder.i18n_cache_lookups = false
-
-# Specifies the class to use for localization lookups. You can create your own
-# class and use it instead by subclassing Formtastic::Localizer (which is the default).
-# Formtastic::FormBuilder.i18n_localizer = MyOwnLocalizer
-
-# You can add custom inputs or override parts of Formtastic by subclassing Formtastic::FormBuilder and
-# specifying that class here.  Defaults to Formtastic::FormBuilder.
-Formtastic::Helpers::FormHelper.builder = FormtasticBootstrap::FormBuilder
-
-# You can opt-in to Formtastic's use of the HTML5 `required` attribute on `<input>`, `<select>`
-# and `<textarea>` tags by setting this to false (defaults to true).
-Formtastic::FormBuilder.use_required_attribute = true
-
-# You can opt-in to new HTML5 browser validations (for things like email and url inputs) by setting
-# this to false. Doing so will add a `novalidate` attribute to the `<form>` tag.
-# See http://diveintohtml5.org/forms.html#validation for more info.
-Formtastic::FormBuilder.perform_browser_validations = true
diff --git a/config/initializers/simple_form.rb b/config/initializers/simple_form.rb
new file mode 100644
index 00000000..a0360439
--- /dev/null
+++ b/config/initializers/simple_form.rb
@@ -0,0 +1,176 @@
+# frozen_string_literal: true
+#
+# Uncomment this and change the path if necessary to include your own
+# components.
+# See https://github.com/plataformatec/simple_form#custom-components to know
+# more about custom components.
+# Dir[Rails.root.join('lib/components/**/*.rb')].each { |f| require f }
+#
+# Use this setup block to configure all options available in SimpleForm.
+SimpleForm.setup do |config|
+  # Wrappers are used by the form builder to generate a
+  # complete input. You can remove any component from the
+  # wrapper, change the order or even add your own to the
+  # stack. The options given below are used to wrap the
+  # whole input.
+  config.wrappers :default, class: :input,
+    hint_class: :field_with_hint, error_class: :field_with_errors, valid_class: :field_without_errors do |b|
+    ## Extensions enabled by default
+    # Any of these extensions can be disabled for a
+    # given input by passing: `f.input EXTENSION_NAME => false`.
+    # You can make any of these extensions optional by
+    # renaming `b.use` to `b.optional`.
+
+    # Determines whether to use HTML5 (:email, :url, ...)
+    # and required attributes
+    b.use :html5
+
+    # Calculates placeholders automatically from I18n
+    # You can also pass a string as f.input placeholder: "Placeholder"
+    b.use :placeholder
+
+    ## Optional extensions
+    # They are disabled unless you pass `f.input EXTENSION_NAME => true`
+    # to the input. If so, they will retrieve the values from the model
+    # if any exists. If you want to enable any of those
+    # extensions by default, you can change `b.optional` to `b.use`.
+
+    # Calculates maxlength from length validations for string inputs
+    # and/or database column lengths
+    b.optional :maxlength
+
+    # Calculate minlength from length validations for string inputs
+    b.optional :minlength
+
+    # Calculates pattern from format validations for string inputs
+    b.optional :pattern
+
+    # Calculates min and max from length validations for numeric inputs
+    b.optional :min_max
+
+    # Calculates readonly automatically from readonly attributes
+    b.optional :readonly
+
+    ## Inputs
+    # b.use :input, class: 'input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :label_input
+    b.use :hint,  wrap_with: { tag: :span, class: :hint }
+    b.use :error, wrap_with: { tag: :span, class: :error }
+
+    ## full_messages_for
+    # If you want to display the full error message for the attribute, you can
+    # use the component :full_error, like:
+    #
+    # b.use :full_error, wrap_with: { tag: :span, class: :error }
+  end
+
+  # The default wrapper to be used by the FormBuilder.
+  config.default_wrapper = :default
+
+  # Define the way to render check boxes / radio buttons with labels.
+  # Defaults to :nested for bootstrap config.
+  #   inline: input + label
+  #   nested: label > input
+  config.boolean_style = :nested
+
+  # Default class for buttons
+  config.button_class = 'btn'
+
+  # Method used to tidy up errors. Specify any Rails Array method.
+  # :first lists the first message for each field.
+  # Use :to_sentence to list all errors for each field.
+  # config.error_method = :first
+
+  # Default tag used for error notification helper.
+  config.error_notification_tag = :div
+
+  # CSS class to add for error notification helper.
+  config.error_notification_class = 'error_notification'
+
+  # Series of attempts to detect a default label method for collection.
+  # config.collection_label_methods = [ :to_label, :name, :title, :to_s ]
+
+  # Series of attempts to detect a default value method for collection.
+  # config.collection_value_methods = [ :id, :to_s ]
+
+  # You can wrap a collection of radio/check boxes in a pre-defined tag, defaulting to none.
+  # config.collection_wrapper_tag = nil
+
+  # You can define the class to use on all collection wrappers. Defaulting to none.
+  # config.collection_wrapper_class = nil
+
+  # You can wrap each item in a collection of radio/check boxes with a tag,
+  # defaulting to :span.
+  # config.item_wrapper_tag = :span
+
+  # You can define a class to use in all item wrappers. Defaulting to none.
+  # config.item_wrapper_class = nil
+
+  # How the label text should be generated altogether with the required text.
+  # config.label_text = lambda { |label, required, explicit_label| "#{required} #{label}" }
+
+  # You can define the class to use on all labels. Default is nil.
+  # config.label_class = nil
+
+  # You can define the default class to be used on forms. Can be overriden
+  # with `html: { :class }`. Defaulting to none.
+  # config.default_form_class = nil
+
+  # You can define which elements should obtain additional classes
+  # config.generate_additional_classes_for = [:wrapper, :label, :input]
+
+  # Whether attributes are required by default (or not). Default is true.
+  # config.required_by_default = true
+
+  # Tell browsers whether to use the native HTML5 validations (novalidate form option).
+  # These validations are enabled in SimpleForm's internal config but disabled by default
+  # in this configuration, which is recommended due to some quirks from different browsers.
+  # To stop SimpleForm from generating the novalidate option, enabling the HTML5 validations,
+  # change this configuration to true.
+  config.browser_validations = true
+
+  # Custom mappings for input types. This should be a hash containing a regexp
+  # to match as key, and the input type that will be used when the field name
+  # matches the regexp as value.
+  # config.input_mappings = { /count/ => :integer }
+
+  # Custom wrappers for input types. This should be a hash containing an input
+  # type as key and the wrapper that will be used for all inputs with specified type.
+  # config.wrapper_mappings = { string: :prepend }
+
+  # Namespaces where SimpleForm should look for custom input classes that
+  # override default inputs.
+  # config.custom_inputs_namespaces << "CustomInputs"
+
+  # Default priority for time_zone inputs.
+  # config.time_zone_priority = nil
+
+  # Default priority for country inputs.
+  # config.country_priority = nil
+
+  # When false, do not use translations for labels.
+  # config.translate_labels = true
+
+  # Automatically discover new inputs in Rails' autoload path.
+  # config.inputs_discovery = true
+
+  # Cache SimpleForm inputs discovery
+  # config.cache_discovery = !Rails.env.development?
+
+  # Default class for inputs
+  # config.input_class = nil
+
+  # Define the default class of the input wrapper of the boolean input.
+  config.boolean_label_class = 'checkbox'
+
+  # Defines if the default input wrapper class should be included in radio
+  # collection wrappers.
+  # config.include_default_input_wrapper_class = true
+
+  # Defines which i18n scope will be used in Simple Form.
+  # config.i18n_scope = 'simple_form'
+
+  # Defines validation classes to the input_field. By default it's nil.
+  # config.input_field_valid_class = 'is-valid'
+  # config.input_field_error_class = 'is-invalid'
+end
diff --git a/config/initializers/simple_form_bootstrap.rb b/config/initializers/simple_form_bootstrap.rb
new file mode 100644
index 00000000..471a64d1
--- /dev/null
+++ b/config/initializers/simple_form_bootstrap.rb
@@ -0,0 +1,440 @@
+# frozen_string_literal: true
+
+# Please do not make direct changes to this file!
+# This generator is maintained by the community around simple_form-bootstrap:
+# https://github.com/rafaelfranca/simple_form-bootstrap
+# All future development, tests, and organization should happen there.
+# Background history: https://github.com/plataformatec/simple_form/issues/1561
+
+# Uncomment this and change the path if necessary to include your own
+# components.
+# See https://github.com/plataformatec/simple_form#custom-components
+# to know more about custom components.
+# Dir[Rails.root.join('lib/components/**/*.rb')].each { |f| require f }
+
+# Use this setup block to configure all options available in SimpleForm.
+SimpleForm.setup do |config|
+  # Default class for buttons
+  config.button_class = 'btn'
+
+  # Define the default class of the input wrapper of the boolean input.
+  config.boolean_label_class = 'form-check-label'
+
+  # How the label text should be generated altogether with the required text.
+  config.label_text = lambda { |label, required, explicit_label| "#{label} #{required}" }
+
+  # Define the way to render check boxes / radio buttons with labels.
+  config.boolean_style = :inline
+
+  # You can wrap each item in a collection of radio/check boxes with a tag
+  config.item_wrapper_tag = :div
+
+  # Defines if the default input wrapper class should be included in radio
+  # collection wrappers.
+  config.include_default_input_wrapper_class = false
+
+  # CSS class to add for error notification helper.
+  config.error_notification_class = 'alert alert-danger'
+
+  # Method used to tidy up errors. Specify any Rails Array method.
+  # :first lists the first message for each field.
+  # :to_sentence to list all errors for each field.
+  config.error_method = :to_sentence
+
+  # add validation classes to `input_field`
+  config.input_field_error_class = 'is-invalid'
+  config.input_field_valid_class = 'is-valid'
+
+
+  # vertical forms
+  #
+  # vertical default_wrapper
+  config.wrappers :vertical_form, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :pattern
+    b.optional :min_max
+    b.optional :readonly
+    b.use :label
+    b.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical input for boolean
+  config.wrappers :vertical_boolean, tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :form_check_wrapper, tag: 'div', class: 'form-check' do |bb|
+      bb.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      bb.use :label, class: 'form-check-label'
+      bb.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+      bb.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # vertical input for radio buttons and check boxes
+  config.wrappers :vertical_collection, item_wrapper_class: 'form-check', item_label_class: 'form-check-label', tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :legend_tag, tag: 'legend', class: 'col-form-label pt-0' do |ba|
+      ba.use :label_text
+    end
+    b.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical input for inline radio buttons and check boxes
+  config.wrappers :vertical_collection_inline, item_wrapper_class: 'form-check form-check-inline', item_label_class: 'form-check-label', tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :legend_tag, tag: 'legend', class: 'col-form-label pt-0' do |ba|
+      ba.use :label_text
+    end
+    b.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical file input
+  config.wrappers :vertical_file, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :readonly
+    b.use :label
+    b.use :input, class: 'form-control-file', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical multi select
+  config.wrappers :vertical_multi_select, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label
+    b.wrapper tag: 'div', class: 'd-flex flex-row justify-content-between align-items-center' do |ba|
+      ba.use :input, class: 'form-control mx-1', error_class: 'is-invalid', valid_class: 'is-valid'
+    end
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # vertical range input
+  config.wrappers :vertical_range, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :readonly
+    b.optional :step
+    b.use :label
+    b.use :input, class: 'form-control-range', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+
+  # horizontal forms
+  #
+  # horizontal default_wrapper
+  config.wrappers :horizontal_form, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :pattern
+    b.optional :min_max
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 col-form-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal input for boolean
+  config.wrappers :horizontal_boolean, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper tag: 'label', class: 'col-sm-3' do |ba|
+      ba.use :label_text
+    end
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |wr|
+      wr.wrapper :form_check_wrapper, tag: 'div', class: 'form-check' do |bb|
+        bb.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+        bb.use :label, class: 'form-check-label'
+        bb.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+        bb.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+      end
+    end
+  end
+
+  # horizontal input for radio buttons and check boxes
+  config.wrappers :horizontal_collection, item_wrapper_class: 'form-check', item_label_class: 'form-check-label', tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 col-form-label pt-0'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal input for inline radio buttons and check boxes
+  config.wrappers :horizontal_collection_inline, item_wrapper_class: 'form-check form-check-inline', item_label_class: 'form-check-label', tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 col-form-label pt-0'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal file input
+  config.wrappers :horizontal_file, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 col-form-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal multi select
+  config.wrappers :horizontal_multi_select, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label, class: 'col-sm-3 col-form-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.wrapper tag: 'div', class: 'd-flex flex-row justify-content-between align-items-center' do |bb|
+        bb.use :input, class: 'form-control mx-1', error_class: 'is-invalid', valid_class: 'is-valid'
+      end
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # horizontal range input
+  config.wrappers :horizontal_range, tag: 'div', class: 'form-group row', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :readonly
+    b.optional :step
+    b.use :label, class: 'col-sm-3 col-form-label'
+    b.wrapper :grid_wrapper, tag: 'div', class: 'col-sm-9' do |ba|
+      ba.use :input, class: 'form-control-range', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+      ba.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+
+  # inline forms
+  #
+  # inline default_wrapper
+  config.wrappers :inline_form, tag: 'span', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :pattern
+    b.optional :min_max
+    b.optional :readonly
+    b.use :label, class: 'sr-only'
+
+    b.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.optional :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # inline input for boolean
+  config.wrappers :inline_boolean, tag: 'span', class: 'form-check mb-2 mr-sm-2', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :input, class: 'form-check-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :label, class: 'form-check-label'
+    b.use :error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.optional :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+
+  # bootstrap custom forms
+  #
+  # custom input for boolean
+  config.wrappers :custom_boolean, tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :form_check_wrapper, tag: 'div', class: 'custom-control custom-checkbox' do |bb|
+      bb.use :input, class: 'custom-control-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      bb.use :label, class: 'custom-control-label'
+      bb.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+      bb.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # custom input switch for boolean
+  config.wrappers :custom_boolean_switch, tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :form_check_wrapper, tag: 'div', class: 'custom-control custom-switch' do |bb|
+      bb.use :input, class: 'custom-control-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      bb.use :label, class: 'custom-control-label'
+      bb.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+      bb.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+    end
+  end
+
+  # custom input for radio buttons and check boxes
+  config.wrappers :custom_collection, item_wrapper_class: 'custom-control', item_label_class: 'custom-control-label', tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :legend_tag, tag: 'legend', class: 'col-form-label pt-0' do |ba|
+      ba.use :label_text
+    end
+    b.use :input, class: 'custom-control-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom input for inline radio buttons and check boxes
+  config.wrappers :custom_collection_inline, item_wrapper_class: 'custom-control custom-control-inline', item_label_class: 'custom-control-label', tag: 'fieldset', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.wrapper :legend_tag, tag: 'legend', class: 'col-form-label pt-0' do |ba|
+      ba.use :label_text
+    end
+    b.use :input, class: 'custom-control-input', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom file input
+  config.wrappers :custom_file, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :readonly
+    b.use :label
+    b.wrapper :custom_file_wrapper, tag: 'div', class: 'custom-file' do |ba|
+      ba.use :input, class: 'custom-file-input', error_class: 'is-invalid', valid_class: 'is-valid'
+      ba.use :label, class: 'custom-file-label'
+      ba.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    end
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom multi select
+  config.wrappers :custom_multi_select, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :label
+    b.wrapper tag: 'div', class: 'd-flex flex-row justify-content-between align-items-center' do |ba|
+      ba.use :input, class: 'custom-select mx-1', error_class: 'is-invalid', valid_class: 'is-valid'
+    end
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom range input
+  config.wrappers :custom_range, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :readonly
+    b.optional :step
+    b.use :label
+    b.use :input, class: 'custom-range', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+
+  # Input Group - custom component
+  # see example app and config at https://github.com/rafaelfranca/simple_form-bootstrap
+  # config.wrappers :input_group, tag: 'div', class: 'form-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+  #   b.use :html5
+  #   b.use :placeholder
+  #   b.optional :maxlength
+  #   b.optional :minlength
+  #   b.optional :pattern
+  #   b.optional :min_max
+  #   b.optional :readonly
+  #   b.use :label
+  #   b.wrapper :input_group_tag, tag: 'div', class: 'input-group' do |ba|
+  #     ba.optional :prepend
+  #     ba.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+  #     ba.optional :append
+  #   end
+  #   b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback d-block' }
+  #   b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  # end
+
+
+  # Floating Labels form
+  #
+  # floating labels default_wrapper
+  config.wrappers :floating_labels_form, tag: 'div', class: 'form-label-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.use :placeholder
+    b.optional :maxlength
+    b.optional :minlength
+    b.optional :pattern
+    b.optional :min_max
+    b.optional :readonly
+    b.use :input, class: 'form-control', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :label
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+  # custom multi select
+  config.wrappers :floating_labels_select, tag: 'div', class: 'form-label-group', error_class: 'form-group-invalid', valid_class: 'form-group-valid' do |b|
+    b.use :html5
+    b.optional :readonly
+    b.use :input, class: 'custom-select', error_class: 'is-invalid', valid_class: 'is-valid'
+    b.use :label
+    b.use :full_error, wrap_with: { tag: 'div', class: 'invalid-feedback' }
+    b.use :hint, wrap_with: { tag: 'small', class: 'form-text text-muted' }
+  end
+
+
+  # The default wrapper to be used by the FormBuilder.
+  config.default_wrapper = :vertical_form
+
+  # Custom wrappers for input types. This should be a hash containing an input
+  # type as key and the wrapper that will be used for all inputs with specified type.
+  config.wrapper_mappings = {
+    boolean:       :vertical_boolean,
+    check_boxes:   :vertical_collection,
+    date:          :vertical_multi_select,
+    datetime:      :vertical_multi_select,
+    file:          :vertical_file,
+    radio_buttons: :vertical_collection,
+    range:         :vertical_range,
+    time:          :vertical_multi_select
+  }
+
+  # enable custom form wrappers
+  # config.wrapper_mappings = {
+  #   boolean:       :custom_boolean,
+  #   check_boxes:   :custom_collection,
+  #   date:          :custom_multi_select,
+  #   datetime:      :custom_multi_select,
+  #   file:          :custom_file,
+  #   radio_buttons: :custom_collection,
+  #   range:         :custom_range,
+  #   time:          :custom_multi_select
+  # }
+end
diff --git a/config/locales/simple_form.en.yml b/config/locales/simple_form.en.yml
new file mode 100644
index 00000000..23743833
--- /dev/null
+++ b/config/locales/simple_form.en.yml
@@ -0,0 +1,31 @@
+en:
+  simple_form:
+    "yes": 'Yes'
+    "no": 'No'
+    required:
+      text: 'required'
+      mark: '*'
+      # You can uncomment the line below if you need to overwrite the whole required html.
+      # When using html, text and mark won't be used.
+      # html: '<abbr title="required">*</abbr>'
+    error_notification:
+      default_message: "Please review the problems below:"
+    # Examples
+    # labels:
+    #   defaults:
+    #     password: 'Password'
+    #   user:
+    #     new:
+    #       email: 'E-mail to sign in.'
+    #     edit:
+    #       email: 'E-mail.'
+    # hints:
+    #   defaults:
+    #     username: 'User name to sign in.'
+    #     password: 'No special characters, please.'
+    # include_blanks:
+    #   defaults:
+    #     age: 'Rather not say'
+    # prompts:
+    #   defaults:
+    #     age: 'Select your age'
diff --git a/lib/templates/haml/scaffold/_form.html.haml b/lib/templates/haml/scaffold/_form.html.haml
index de6af813..849155a5 100644
--- a/lib/templates/haml/scaffold/_form.html.haml
+++ b/lib/templates/haml/scaffold/_form.html.haml
@@ -1,8 +1,12 @@
-= semantic_form_for @<%= singular_name %> do |f|
-  = f.inputs do
+-# frozen_string_literal: true
+= simple_form_for(@<%= singular_table_name %>) do |f|
+  = f.error_notification
+  = f.error_notification message: f.object.errors[:base].to_sentence if f.object.errors[:base].present?
+
+  .form-inputs
   <%- attributes.each do |attribute| -%>
-    = f.input :<%= attribute.name %>
+    = f.<%= attribute.reference? ? :association : :input %> :<%= attribute.name %>
   <%- end -%>
 
-  = f.actions do
-    = f.action :submit, :as => :input
+  .form-actions
+    = f.button :submit