diff --git a/.env.example b/.env.example
index 4bf6b30..cf01e61 100644
--- a/.env.example
+++ b/.env.example
@@ -1,3 +1,4 @@
 SECRET_KEY_BASE=
 IMAP_SERVER=
 DEFAULT_FROM=
+DEVISE_PEPPER=
diff --git a/.rubocop.yml b/.rubocop.yml
index febceec..980b6f0 100644
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -12,3 +12,7 @@ Metrics/MethodLength:
   Exclude:
     - 'db/schema.rb'
     - 'db/migrate/*.rb'
+
+Metrics/BlockLength:
+  Exclude:
+    - 'config/initializers/devise.rb'
diff --git a/Gemfile b/Gemfile
index 0a0406f..578a8ae 100644
--- a/Gemfile
+++ b/Gemfile
@@ -22,9 +22,11 @@ gem 'uglifier', '>= 1.3.0'
 # See https://github.com/rails/execjs#readme for more supported runtimes
 # gem 'therubyracer', platforms: :ruby
 
-# Turbolinks makes navigating your web application faster. Read more: https://github.com/turbolinks/turbolinks
+# Turbolinks makes navigating your web application faster. Read more:
+# https://github.com/turbolinks/turbolinks
 gem 'turbolinks', '~> 5'
-# Build JSON APIs with ease. Read more: https://github.com/rails/jbuilder
+# Build JSON APIs with ease. Read more:
+# https://github.com/rails/jbuilder
 gem 'jbuilder', '~> 2.5'
 # Use ActiveModel has_secure_password
 gem 'bcrypt', '~> 3.1.7'
@@ -37,6 +39,8 @@ gem 'carrierwave'
 gem 'carrierwave-bombshelter'
 gem 'carrierwave-i18n'
 gem 'commonmarker'
+gem 'devise'
+gem 'devise-i18n'
 gem 'email_address'
 gem 'exception_notification'
 gem 'font-awesome-rails'
@@ -56,10 +60,12 @@ group :development, :test do
 end
 
 group :development do
-  # Access an IRB console on exception pages or by using <%= console %> anywhere in the code.
+  # Access an IRB console on exception pages or by using <%= console %>
+  # anywhere in the code.
   gem 'listen', '>= 3.0.5', '< 3.2'
   gem 'web-console', '>= 3.3.0'
-  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
+  # Spring speeds up development by keeping your application running in
+  # the background. Read more: https://github.com/rails/spring
   gem 'bcrypt_pbkdf'
   gem 'capistrano'
   gem 'capistrano-bundler'
diff --git a/Gemfile.lock b/Gemfile.lock
index 49fb3de..a9572c0 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -98,6 +98,14 @@ GEM
       ruby-enum (~> 0.5)
     concurrent-ruby (1.1.5)
     crass (1.0.4)
+    devise (4.6.2)
+      bcrypt (~> 3.0)
+      orm_adapter (~> 0.1)
+      railties (>= 4.1.0, < 6.0)
+      responders
+      warden (~> 1.2.3)
+    devise-i18n (1.8.0)
+      devise (>= 4.6)
     dotenv (2.7.2)
     dotenv-rails (2.7.2)
       dotenv (= 2.7.2)
@@ -200,6 +208,7 @@ GEM
     nio4r (2.3.1)
     nokogiri (1.10.2)
       mini_portile2 (~> 2.4.0)
+    orm_adapter (0.5.0)
     parallel (1.16.0)
     parser (2.6.2.0)
       ast (~> 2.4.0)
@@ -250,6 +259,9 @@ GEM
       ffi (~> 1.0)
     rbnacl (4.0.2)
       ffi
+    responders (3.0.0)
+      actionpack (>= 5.0)
+      railties (>= 5.0)
     rouge (3.3.0)
     rubocop (0.66.0)
       jaro_winkler (~> 1.5.1)
@@ -347,6 +359,8 @@ DEPENDENCIES
   carrierwave-bombshelter
   carrierwave-i18n
   commonmarker
+  devise
+  devise-i18n
   dotenv-rails
   ed25519
   email_address
@@ -377,4 +391,4 @@ DEPENDENCIES
   whenever
 
 BUNDLED WITH
-   1.17.1
+   1.17.3
diff --git a/app/views/devise/confirmations/new.haml b/app/views/devise/confirmations/new.haml
new file mode 100644
index 0000000..cb4c1d7
--- /dev/null
+++ b/app/views/devise/confirmations/new.haml
@@ -0,0 +1,10 @@
+%h2= t('.resend_confirmation_instructions')
+= form_for(resource, as: resource_name, url: confirmation_path(resource_name), html: { method: :post }) do |f|
+  = render "devise/shared/error_messages", resource: resource
+  .field
+    = f.label :email
+    %br/
+    = f.email_field :email, autofocus: true, autocomplete: "email", value: (resource.pending_reconfirmation? ? resource.unconfirmed_email : resource.email)
+  .actions
+    = f.submit t('.resend_confirmation_instructions')
+= render "devise/shared/links"
diff --git a/app/views/devise/mailer/confirmation_instructions.haml b/app/views/devise/mailer/confirmation_instructions.haml
new file mode 100644
index 0000000..46706c4
--- /dev/null
+++ b/app/views/devise/mailer/confirmation_instructions.haml
@@ -0,0 +1,3 @@
+%p= t('.greeting', recipient: @email)
+%p= t('.instruction')
+%p= link_to t('.action'), confirmation_url(@resource, confirmation_token: @token)
diff --git a/app/views/devise/mailer/email_changed.haml b/app/views/devise/mailer/email_changed.haml
new file mode 100644
index 0000000..8ae4d38
--- /dev/null
+++ b/app/views/devise/mailer/email_changed.haml
@@ -0,0 +1,5 @@
+%p= t('.greeting', recipient: @email)
+- if @resource.try(:unconfirmed_email?)
+  %p= t('.message', email: @resource.unconfirmed_email)
+- else
+  %p= t('.message', email: @resource.email)
diff --git a/app/views/devise/mailer/password_change.haml b/app/views/devise/mailer/password_change.haml
new file mode 100644
index 0000000..ebb43d0
--- /dev/null
+++ b/app/views/devise/mailer/password_change.haml
@@ -0,0 +1,2 @@
+%p= t('.greeting', recipient: @resource.email)
+%p= t('.message')
diff --git a/app/views/devise/mailer/reset_password_instructions.haml b/app/views/devise/mailer/reset_password_instructions.haml
new file mode 100644
index 0000000..ccc4aa5
--- /dev/null
+++ b/app/views/devise/mailer/reset_password_instructions.haml
@@ -0,0 +1,5 @@
+%p= t('.greeting', recipient: @resource.email)
+%p= t('.instruction')
+%p= link_to t('.action'), edit_password_url(@resource, reset_password_token: @token)
+%p= t('.instruction_2')
+%p= t('.instruction_3')
diff --git a/app/views/devise/mailer/unlock_instructions.haml b/app/views/devise/mailer/unlock_instructions.haml
new file mode 100644
index 0000000..d68bf7c
--- /dev/null
+++ b/app/views/devise/mailer/unlock_instructions.haml
@@ -0,0 +1,4 @@
+%p= t('.greeting', recipient: @resource.email)
+%p= t('.message')
+%p= t('.instruction')
+%p= link_to t('.action'), unlock_url(@resource, unlock_token: @token)
diff --git a/app/views/devise/passwords/edit.haml b/app/views/devise/passwords/edit.haml
new file mode 100644
index 0000000..f492ff8
--- /dev/null
+++ b/app/views/devise/passwords/edit.haml
@@ -0,0 +1,18 @@
+%h2= t('.change_your_password')
+= form_for(resource, as: resource_name, url: password_path(resource_name), html: { method: :put }) do |f|
+  = render "devise/shared/error_messages", resource: resource
+  = f.hidden_field :reset_password_token
+  .field
+    = f.label :password, t('.new_password')
+    %br/
+    - if @minimum_password_length
+      %em= t('devise.shared.minimum_password_length', count: @minimum_password_length)
+      %br/
+    = f.password_field :password, autofocus: true, autocomplete: "new-password"
+  .field
+    = f.label :password_confirmation, t('.confirm_new_password')
+    %br/
+    = f.password_field :password_confirmation, autocomplete: "off"
+  .actions
+    = f.submit t('.change_my_password')
+= render "devise/shared/links"
diff --git a/app/views/devise/passwords/new.haml b/app/views/devise/passwords/new.haml
new file mode 100644
index 0000000..39936f3
--- /dev/null
+++ b/app/views/devise/passwords/new.haml
@@ -0,0 +1,10 @@
+%h2= t('.forgot_your_password')
+= form_for(resource, as: resource_name, url: password_path(resource_name), html: { method: :post }) do |f|
+  = render "devise/shared/error_messages", resource: resource
+  .field
+    = f.label :email
+    %br/
+    = f.email_field :email, autofocus: true, autocomplete: "email"
+  .actions
+    = f.submit t('.send_me_reset_password_instructions')
+= render "devise/shared/links"
diff --git a/app/views/devise/registrations/edit.haml b/app/views/devise/registrations/edit.haml
new file mode 100644
index 0000000..9b7f4f0
--- /dev/null
+++ b/app/views/devise/registrations/edit.haml
@@ -0,0 +1,35 @@
+%h2= t('.title', resource: resource.model_name.human)
+= form_for(resource, as: resource_name, url: registration_path(resource_name), html: { method: :put }) do |f|
+  = render "devise/shared/error_messages", resource: resource
+  .field
+    = f.label :email
+    %br/
+    = f.email_field :email, autofocus: true, autocomplete: "email"
+  - if devise_mapping.confirmable? && resource.pending_reconfirmation?
+    %div= t('.currently_waiting_confirmation_for_email', email: resource.unconfirmed_email)
+  .field
+    = f.label :password
+    %i
+      (#{t('.leave_blank_if_you_don_t_want_to_change_it')})
+    %br/
+    = f.password_field :password, autocomplete: "new-password"
+    - if @minimum_password_length
+      %br/
+      %em= t('devise.shared.minimum_password_length', count: @minimum_password_length)
+  .field
+    = f.label :password_confirmation
+    %br/
+    = f.password_field :password_confirmation, autocomplete: "new-password"
+  .field
+    = f.label :current_password
+    %i
+      (#{t('.we_need_your_current_password_to_confirm_your_changes')})
+    %br/
+    = f.password_field :current_password, autocomplete: "current-password"
+  .actions
+    = f.submit t('.update')
+%h3= t('.cancel_my_account')
+%p
+  = t('.unhappy')
+  = button_to t('.cancel_my_account'), registration_path(resource_name), data: { confirm: t('.are_you_sure') }, method: :delete
+= link_to t('devise.shared.links.back'), :back
diff --git a/app/views/devise/registrations/new.haml b/app/views/devise/registrations/new.haml
new file mode 100644
index 0000000..21fec96
--- /dev/null
+++ b/app/views/devise/registrations/new.haml
@@ -0,0 +1,20 @@
+%h2= t('.sign_up')
+= form_for(resource, as: resource_name, url: registration_path(resource_name)) do |f|
+  = render "devise/shared/error_messages", resource: resource
+  .field
+    = f.label :email
+    %br/
+    = f.email_field :email, autofocus: true, autocomplete: "email"
+  .field
+    = f.label :password
+    - if @minimum_password_length
+      %em= t('devise.shared.minimum_password_length', count: @minimum_password_length)
+    %br/
+    = f.password_field :password, autocomplete: "new-password"
+  .field
+    = f.label :password_confirmation
+    %br/
+    = f.password_field :password_confirmation, autocomplete: "new-password"
+  .actions
+    = f.submit t('.sign_up')
+= render "devise/shared/links"
diff --git a/app/views/devise/sessions/new.haml b/app/views/devise/sessions/new.haml
new file mode 100644
index 0000000..625e380
--- /dev/null
+++ b/app/views/devise/sessions/new.haml
@@ -0,0 +1,17 @@
+%h2= t('.sign_in')
+= form_for(resource, as: resource_name, url: session_path(resource_name)) do |f|
+  .field
+    = f.label :email
+    %br/
+    = f.email_field :email, autofocus: true, autocomplete: "email"
+  .field
+    = f.label :password
+    %br/
+    = f.password_field :password, autocomplete: "current-password"
+  - if devise_mapping.rememberable?
+    .field
+      = f.check_box :remember_me
+      = f.label :remember_me
+  .actions
+    = f.submit t('.sign_in')
+= render "devise/shared/links"
diff --git a/app/views/devise/shared/_error_messages.haml b/app/views/devise/shared/_error_messages.haml
new file mode 100644
index 0000000..a921fd6
--- /dev/null
+++ b/app/views/devise/shared/_error_messages.haml
@@ -0,0 +1,9 @@
+- if resource.errors.any?
+  #error_explanation
+    %h2
+      = I18n.t("errors.messages.not_saved",                 |
+        count: resource.errors.count,                       |
+        resource: resource.class.model_name.human.downcase) |
+    %ul
+      - resource.errors.full_messages.each do |message|
+        %li= message
diff --git a/app/views/devise/shared/_links.haml b/app/views/devise/shared/_links.haml
new file mode 100644
index 0000000..5577592
--- /dev/null
+++ b/app/views/devise/shared/_links.haml
@@ -0,0 +1,19 @@
+- if controller_name != 'sessions'
+  = link_to t(".sign_in"), new_session_path(resource_name)
+  %br/
+- if devise_mapping.registerable? && controller_name != 'registrations'
+  = link_to t(".sign_up"), new_registration_path(resource_name)
+  %br/
+- if devise_mapping.recoverable? && controller_name != 'passwords' && controller_name != 'registrations'
+  = link_to t(".forgot_your_password"), new_password_path(resource_name)
+  %br/
+- if devise_mapping.confirmable? && controller_name != 'confirmations'
+  = link_to t('.didn_t_receive_confirmation_instructions'), new_confirmation_path(resource_name)
+  %br/
+- if devise_mapping.lockable? && resource_class.unlock_strategy_enabled?(:email) && controller_name != 'unlocks'
+  = link_to t('.didn_t_receive_unlock_instructions'), new_unlock_path(resource_name)
+  %br/
+- if devise_mapping.omniauthable?
+  - resource_class.omniauth_providers.each do |provider|
+    = link_to t('.sign_in_with_provider', provider: OmniAuth::Utils.camelize(provider)), omniauth_authorize_path(resource_name, provider)
+    %br/
diff --git a/app/views/devise/unlocks/new.haml b/app/views/devise/unlocks/new.haml
new file mode 100644
index 0000000..f381615
--- /dev/null
+++ b/app/views/devise/unlocks/new.haml
@@ -0,0 +1,10 @@
+%h2= t('.resend_unlock_instructions')
+= form_for(resource, as: resource_name, url: unlock_path(resource_name), html: { method: :post }) do |f|
+  = render "devise/shared/error_messages", resource: resource
+  .field
+    = f.label :email
+    %br/
+    = f.email_field :email, autofocus: true, autocomplete: "email"
+  .actions
+    = f.submit t('.resend_unlock_instructions')
+= render "devise/shared/links"
diff --git a/app/views/layouts/mailer.haml b/app/views/layouts/mailer.haml
new file mode 100644
index 0000000..cbf6b8e
--- /dev/null
+++ b/app/views/layouts/mailer.haml
@@ -0,0 +1,8 @@
+!!!
+%html
+  %head
+    %meta{:content => "text/html; charset=utf-8", "http-equiv" => "Content-Type"}/
+    :css
+      /* Email styles need to be inline */
+  %body
+    = yield
diff --git a/app/views/layouts/mailer.html.erb b/app/views/layouts/mailer.html.erb
deleted file mode 100644
index cbd34d2..0000000
--- a/app/views/layouts/mailer.html.erb
+++ /dev/null
@@ -1,13 +0,0 @@
-<!DOCTYPE html>
-<html>
-  <head>
-    <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
-    <style>
-      /* Email styles need to be inline */
-    </style>
-  </head>
-
-  <body>
-    <%= yield %>
-  </body>
-</html>
diff --git a/config/initializers/devise.rb b/config/initializers/devise.rb
new file mode 100644
index 0000000..256b37e
--- /dev/null
+++ b/config/initializers/devise.rb
@@ -0,0 +1,336 @@
+# frozen_string_literal: true
+
+# Use this hook to configure devise mailer, warden hooks and so forth.
+# Many of these configuration options can be set straight in your model.
+Devise.setup do |config|
+  # The secret key used by Devise. Devise uses this key to generate
+  # random tokens. Changing this key will render invalid all existing
+  # confirmation, reset password and unlock tokens in the database.
+  # Devise will use the `secret_key_base` as its `secret_key`
+  # by default. You can change it below and use your own secret key.
+  # config.secret_key = ''
+
+  # ==> Controller configuration
+  # Configure the parent class to the devise controllers.
+  # config.parent_controller = 'DeviseController'
+
+  # ==> Mailer Configuration
+  # Configure the e-mail address which will be shown in Devise::Mailer,
+  # note that it will be overwritten if you use your own mailer class
+  # with default "from" parameter.
+  config.mailer_sender = ENV['DEFAULT_FROM']
+
+  # Configure the class responsible to send e-mails.
+  # config.mailer = 'Devise::Mailer'
+
+  # Configure the parent class responsible to send e-mails.
+  # config.parent_mailer = 'ActionMailer::Base'
+
+  # ==> ORM configuration
+  # Load and configure the ORM. Supports :active_record (default) and
+  # :mongoid (bson_ext recommended) by default. Other ORMs may be
+  # available as additional gems.
+  require 'devise/orm/active_record'
+
+  # ==> Configuration for any authentication mechanism
+  #
+  # Configure which keys are used when authenticating a user. The
+  # default is just :email. You can configure it to use [:username,
+  # :subdomain], so for authenticating a user, both parameters are
+  # required. Remember that those parameters are used only when
+  # authenticating and not when retrieving from session. If you need
+  # permissions, you should implement that in a before filter.  You can
+  # also supply a hash where the value is a boolean determining whether
+  # or not authentication should be aborted when the value is not
+  # present.
+  # config.authentication_keys = [:email]
+
+  # Configure parameters from the request object used for
+  # authentication. Each entry given should be a request method and it
+  # will automatically be passed to the find_for_authentication method
+  # and considered in your model lookup. For instance, if you set
+  # :request_keys to [:subdomain], :subdomain will be used on
+  # authentication.  The same considerations mentioned for
+  # authentication_keys also apply to request_keys.
+  # config.request_keys = []
+
+  # Configure which authentication keys should be case-insensitive.
+  # These keys will be downcased upon creating or modifying a user and
+  # when used to authenticate or find a user. Default is :email.
+  config.case_insensitive_keys = [:email]
+
+  # Configure which authentication keys should have whitespace stripped.
+  # These keys will have whitespace before and after removed upon
+  # creating or modifying a user and when used to authenticate or find a
+  # user. Default is :email.
+  config.strip_whitespace_keys = [:email]
+
+  # Tell if authentication through request.params is enabled. True by
+  # default.  It can be set to an array that will enable params
+  # authentication only for the given strategies, for example,
+  # `config.params_authenticatable = [:database]` will enable it only
+  # for database (email + password) authentication.
+  # config.params_authenticatable = true
+
+  # Tell if authentication through HTTP Auth is enabled. False by
+  # default.  It can be set to an array that will enable http
+  # authentication only for the given strategies, for example,
+  # `config.http_authenticatable = [:database]` will enable it only for
+  # database authentication. The supported strategies are: :database
+  # = Support basic authentication with authentication key + password
+  # config.http_authenticatable = false
+
+  # If 401 status code should be returned for AJAX requests. True by
+  # default.
+  # config.http_authenticatable_on_xhr = true
+
+  # The realm used in Http Basic Authentication. 'Application' by
+  # default.
+  # config.http_authentication_realm = 'Application'
+
+  # It will change confirmation, password recovery and other workflows
+  # to behave the same regardless if the e-mail provided was right or
+  # wrong.  Does not affect registerable.
+  # config.paranoid = true
+
+  # By default Devise will store the user in session. You can skip
+  # storage for particular strategies by setting this option.
+  # Notice that if you are skipping storage for all authentication
+  # paths, you may want to disable generating routes to Devise's
+  # sessions controller by passing skip: :sessions to `devise_for` in
+  # your config/routes.rb
+  config.skip_session_storage = [:http_auth]
+
+  # By default, Devise cleans up the CSRF token on authentication to
+  # avoid CSRF token fixation attacks. This means that, when using AJAX
+  # requests for sign in and sign up, you need to get a new CSRF token
+  # from the server. You can disable this option at your own risk.
+  # config.clean_up_csrf_token_on_authentication = true
+
+  # When false, Devise will not attempt to reload routes on eager load.
+  # This can reduce the time taken to boot the app but if your
+  # application requires the Devise mappings to be loaded during boot
+  # time the application won't boot properly.
+  # config.reload_routes = true
+
+  # ==> Configuration for :database_authenticatable
+  # For bcrypt, this is the cost for hashing the password and defaults
+  # to 11. If using other algorithms, it sets how many times you want
+  # the password to be hashed.
+  #
+  # Limiting the stretches to just one in testing will increase the
+  # performance of your test suite dramatically. However, it is STRONGLY
+  # RECOMMENDED to not use a value less than 10 in other environments.
+  # Note that, for bcrypt (the default algorithm), the cost increases
+  # exponentially with the number of stretches (e.g.  a value of 20 is
+  # already extremely slow: approx. 60 seconds for 1 calculation).
+  config.stretches = Rails.env.test? ? 1 : 11
+
+  # Set up a pepper to generate the hashed password.
+  config.pepper = ENV['DEVISE_PEPPER']
+
+  # Send a notification to the original email when the user's email is
+  # changed.
+  config.send_email_changed_notification = true
+
+  # Send a notification email when the user's password is changed.
+  config.send_password_change_notification = true
+
+  # ==> Configuration for :confirmable
+  # A period that the user is allowed to access the website even without
+  # confirming their account. For instance, if set to 2.days, the user
+  # will be able to access the website for two days without confirming
+  # their account, access will be blocked just in the third day.
+  # You can also set it to nil, which will allow the user to access the
+  # website without confirming their account.
+  # Default is 0.days, meaning the user cannot access the website
+  # without confirming their account.
+  config.allow_unconfirmed_access_for = 2.days
+
+  # A period that the user is allowed to confirm their account before
+  # their token becomes invalid. For example, if set to 3.days, the user
+  # can confirm their account within 3 days after the mail was sent, but
+  # on the fourth day their account can't be confirmed with the token
+  # any more.  Default is nil, meaning there is no restriction on how
+  # long a user can take before confirming their account.
+  config.confirm_within = 3.days
+
+  # If true, requires any email changes to be confirmed (exactly the
+  # same way as initial account confirmation) to be applied. Requires
+  # additional unconfirmed_email db field (see migrations). Until
+  # confirmed, new email is stored in unconfirmed_email column, and
+  # copied to email column on successful confirmation.
+  config.reconfirmable = true
+
+  # Defines which key will be used when confirming an account
+  # config.confirmation_keys = [:email]
+
+  # ==> Configuration for :rememberable
+  # The time the user will be remembered without asking for credentials
+  # again.
+  # config.remember_for = 2.weeks
+
+  # Invalidates all the remember me tokens when the user signs out.
+  config.expire_all_remember_me_on_sign_out = true
+
+  # If true, extends the user's remember period when remembered via
+  # cookie.
+  # config.extend_remember_period = false
+
+  # Options to be passed to the created cookie. For instance, you can
+  # set secure: true in order to force SSL only cookies.
+  # config.rememberable_options = {}
+
+  # ==> Configuration for :validatable
+  # Range for password length.
+  config.password_length = 8..128
+
+  # Email regex used to validate email formats. It simply asserts that
+  # one (and only one) @ exists in the given string. This is mainly
+  # to give user feedback and not to assert the e-mail validity.
+  config.email_regexp = /\A[^@\s]+@[^@\s]+\z/
+
+  # ==> Configuration for :timeoutable
+  # The time you want to timeout the user session without activity.
+  # After this time the user will be asked for credentials again.
+  # Default is 30 minutes.
+  # config.timeout_in = 30.minutes
+
+  # ==> Configuration for :lockable
+  #
+  # Defines which strategy will be used to lock an account.
+  # :failed_attempts = Locks an account after a number of failed
+  # attempts to sign in.
+  # :none            = No lock strategy. You should handle locking by
+  # yourself.
+  config.lock_strategy = :failed_attempts
+
+  # Defines which key will be used when locking and unlocking an account
+  # config.unlock_keys = [:email]
+
+  # Defines which strategy will be used to unlock an account.
+  # :email = Sends an unlock link to the user email
+  # :time  = Re-enables login after a certain amount of time (see
+  # :unlock_in below)
+  # :both  = Enables both strategies
+  # :none  = No unlock strategy. You should handle unlocking by
+  # yourself.
+  config.unlock_strategy = :both
+
+  # Number of authentication tries before locking an account if
+  # lock_strategy is failed attempts.
+  config.maximum_attempts = 20
+
+  # Time interval to unlock the account if :time is enabled as
+  # unlock_strategy.
+  config.unlock_in = 1.hour
+
+  # Warn on the last attempt before the account is locked.
+  # config.last_attempt_warning = true
+
+  # ==> Configuration for :recoverable
+  #
+  # Defines which key will be used when recovering the password for an
+  # account
+  # config.reset_password_keys = [:email]
+
+  # Time interval you can reset your password with a reset password key.
+  # Don't put a too small interval or your users won't have the time to
+  # change their passwords.
+  config.reset_password_within = 6.hours
+
+  # When set to false, does not sign a user in automatically after their
+  # password is reset. Defaults to true, so a user is signed in
+  # automatically after a reset.
+  config.sign_in_after_reset_password = true
+
+  # ==> Configuration for :encryptable
+  # Allow you to use another hashing or encryption algorithm besides
+  # bcrypt (default).  You can use :sha1, :sha512 or algorithms from
+  # others authentication tools as :clearance_sha1, :authlogic_sha512
+  # (then you should set stretches above to 20 for default behavior) and
+  # :restful_authentication_sha1 (then you should set stretches to 10,
+  # and copy REST_AUTH_SITE_KEY to pepper).
+  #
+  # Require the `devise-encryptable` gem when using anything other than
+  # bcrypt
+  # config.encryptor = :sha512
+
+  # ==> Scopes configuration
+  # Turn scoped views on. Before rendering "sessions/new", it will first
+  # check for "users/sessions/new". It's turned off by default because
+  # it's slower if you are using only default views.
+  # config.scoped_views = false
+
+  # Configure the default scope given to Warden. By default it's the
+  # first devise role declared in your routes (usually :user).
+  # config.default_scope = :user
+
+  # Set this configuration to false if you want /users/sign_out to sign
+  # out only the current scope. By default, Devise signs out all scopes.
+  # config.sign_out_all_scopes = true
+
+  # ==> Navigation configuration
+  # Lists the formats that should be treated as navigational. Formats
+  # like :html, should redirect to the sign in page when the user does
+  # not have access, but formats like :xml or :json, should return 401.
+  #
+  # If you have any extra navigational formats, like :iphone or :mobile,
+  # you should add them to the navigational formats lists.
+  #
+  # The "*/*" below is required to match Internet Explorer requests.
+  # config.navigational_formats = ['*/*', :html]
+
+  # The default HTTP method used to sign out a resource. Default is
+  # :delete.
+  config.sign_out_via = :delete
+
+  # ==> OmniAuth
+  # Add a new OmniAuth provider. Check the wiki for more information on
+  # setting up on your models and hooks.
+  #
+  # config.omniauth :github, 'APP_ID', 'APP_SECRET', scope:
+  # 'user,public_repo'
+
+  # ==> Warden configuration
+  #
+  # If you want to use other strategies, that are not supported by
+  # Devise, or change the failure app, you can configure them inside the
+  # config.warden block.
+  #
+  # config.warden do |manager|
+  #   manager.intercept_401 = false
+  #   manager.default_strategies(scope: :user)
+  #     .unshift :some_external_strategy
+  # end
+
+  # ==> Mountable engine configurations
+  #
+  # When using Devise inside an engine, let's call it `MyEngine`, and
+  # this engine is mountable, there are some extra configurations to be
+  # taken into account.  The following options are available, assuming
+  # the engine is mounted as:
+  #
+  #     mount MyEngine, at: '/my_engine'
+  #
+  # The router that invoked `devise_for`, in the example above, would
+  # be: config.router_name = :my_engine
+  #
+  # When using OmniAuth, Devise cannot automatically set OmniAuth path,
+  # so you need to do it manually. For the users scope, it would be:
+  # config.omniauth_path_prefix = '/my_engine/users/auth'
+
+  # ==> Turbolinks configuration
+  #
+  # If your app is using Turbolinks, Turbolinks::Controller needs to be
+  # included to make redirection work correctly:
+  ActiveSupport.on_load(:devise_failure_app) do
+    include Turbolinks::Controller
+  end
+
+  # ==> Configuration for :registerable
+  # When set to false, does not sign a user in automatically after their
+  # password is changed. Defaults to true, so a user is signed in
+  # automatically after changing a password.
+  config.sign_in_after_change_password = true
+end
diff --git a/config/locales/devise.en.yml b/config/locales/devise.en.yml
new file mode 100644
index 0000000..55617bd
--- /dev/null
+++ b/config/locales/devise.en.yml
@@ -0,0 +1,65 @@
+# Additional translations at https://github.com/plataformatec/devise/wiki/I18n
+
+en:
+  devise:
+    confirmations:
+      confirmed: "Your email address has been successfully confirmed."
+      send_instructions: "You will receive an email with instructions for how to confirm your email address in a few minutes."
+      send_paranoid_instructions: "If your email address exists in our database, you will receive an email with instructions for how to confirm your email address in a few minutes."
+    failure:
+      already_authenticated: "You are already signed in."
+      inactive: "Your account is not activated yet."
+      invalid: "Invalid %{authentication_keys} or password."
+      locked: "Your account is locked."
+      last_attempt: "You have one more attempt before your account is locked."
+      not_found_in_database: "Invalid %{authentication_keys} or password."
+      timeout: "Your session expired. Please sign in again to continue."
+      unauthenticated: "You need to sign in or sign up before continuing."
+      unconfirmed: "You have to confirm your email address before continuing."
+    mailer:
+      confirmation_instructions:
+        subject: "Confirmation instructions"
+      reset_password_instructions:
+        subject: "Reset password instructions"
+      unlock_instructions:
+        subject: "Unlock instructions"
+      email_changed:
+        subject: "Email Changed"
+      password_change:
+        subject: "Password Changed"
+    omniauth_callbacks:
+      failure: "Could not authenticate you from %{kind} because \"%{reason}\"."
+      success: "Successfully authenticated from %{kind} account."
+    passwords:
+      no_token: "You can't access this page without coming from a password reset email. If you do come from a password reset email, please make sure you used the full URL provided."
+      send_instructions: "You will receive an email with instructions on how to reset your password in a few minutes."
+      send_paranoid_instructions: "If your email address exists in our database, you will receive a password recovery link at your email address in a few minutes."
+      updated: "Your password has been changed successfully. You are now signed in."
+      updated_not_active: "Your password has been changed successfully."
+    registrations:
+      destroyed: "Bye! Your account has been successfully cancelled. We hope to see you again soon."
+      signed_up: "Welcome! You have signed up successfully."
+      signed_up_but_inactive: "You have signed up successfully. However, we could not sign you in because your account is not yet activated."
+      signed_up_but_locked: "You have signed up successfully. However, we could not sign you in because your account is locked."
+      signed_up_but_unconfirmed: "A message with a confirmation link has been sent to your email address. Please follow the link to activate your account."
+      update_needs_confirmation: "You updated your account successfully, but we need to verify your new email address. Please check your email and follow the confirm link to confirm your new email address."
+      updated: "Your account has been updated successfully."
+      updated_but_not_signed_in: "Your account has been updated successfully, but since your password was changed, you need to sign in again"
+    sessions:
+      signed_in: "Signed in successfully."
+      signed_out: "Signed out successfully."
+      already_signed_out: "Signed out successfully."
+    unlocks:
+      send_instructions: "You will receive an email with instructions for how to unlock your account in a few minutes."
+      send_paranoid_instructions: "If your account exists, you will receive an email with instructions for how to unlock it in a few minutes."
+      unlocked: "Your account has been unlocked successfully. Please sign in to continue."
+  errors:
+    messages:
+      already_confirmed: "was already confirmed, please try signing in"
+      confirmation_period_expired: "needs to be confirmed within %{period}, please request a new one"
+      expired: "has expired, please request a new one"
+      not_found: "not found"
+      not_locked: "was not locked"
+      not_saved:
+        one: "1 error prohibited this %{resource} from being saved:"
+        other: "%{count} errors prohibited this %{resource} from being saved:"
diff --git a/config/locales/devise.views.en.yml b/config/locales/devise.views.en.yml
new file mode 100644
index 0000000..aa0697c
--- /dev/null
+++ b/config/locales/devise.views.en.yml
@@ -0,0 +1,146 @@
+en:
+  activerecord:
+    attributes:
+      user:
+        confirmation_sent_at: Confirmation sent at
+        confirmation_token: Confirmation token
+        confirmed_at: Confirmed at
+        created_at: Created at
+        current_password: Current password
+        current_sign_in_at: Current sign in at
+        current_sign_in_ip: Current sign in IP
+        email: Email
+        encrypted_password: Encrypted password
+        failed_attempts: Failed attempts
+        last_sign_in_at: Last sign in at
+        last_sign_in_ip: Last sign in IP
+        locked_at: Locked at
+        password: Password
+        password_confirmation: Password confirmation
+        remember_created_at: Remember created at
+        remember_me: Remember me
+        reset_password_sent_at: Reset password sent at
+        reset_password_token: Reset password token
+        sign_in_count: Sign in count
+        unconfirmed_email: Unconfirmed email
+        unlock_token: Unlock token
+        updated_at: Updated at
+    models:
+      user:
+        one: User
+        other: Users
+  devise:
+    confirmations:
+      confirmed: Your email address has been successfully confirmed.
+      new:
+        resend_confirmation_instructions: Resend confirmation instructions
+      send_instructions: You will receive an email with instructions for how to confirm your email address in a few minutes.
+      send_paranoid_instructions: If your email address exists in our database, you will receive an email with instructions for how to confirm your email address in a few minutes.
+    failure:
+      already_authenticated: You are already signed in.
+      inactive: Your account is not activated yet.
+      invalid: Invalid %{authentication_keys} or password.
+      last_attempt: You have one more attempt before your account is locked.
+      locked: Your account is locked.
+      not_found_in_database: Invalid %{authentication_keys} or password.
+      timeout: Your session expired. Please sign in again to continue.
+      unauthenticated: You need to sign in or sign up before continuing.
+      unconfirmed: You have to confirm your email address before continuing.
+    mailer:
+      confirmation_instructions:
+        action: Confirm my account
+        greeting: Welcome %{recipient}!
+        instruction: 'You can confirm your account email through the link below:'
+        subject: Confirmation instructions
+      email_changed:
+        greeting: Hello %{recipient}!
+        message: We're contacting you to notify you that your email has been changed to %{email}.
+        subject: Email Changed
+      password_change:
+        greeting: Hello %{recipient}!
+        message: We're contacting you to notify you that your password has been changed.
+        subject: Password Changed
+      reset_password_instructions:
+        action: Change my password
+        greeting: Hello %{recipient}!
+        instruction: Someone has requested a link to change your password. You can do this through the link below.
+        instruction_2: If you didn't request this, please ignore this email.
+        instruction_3: Your password won't change until you access the link above and create a new one.
+        subject: Reset password instructions
+      unlock_instructions:
+        action: Unlock my account
+        greeting: Hello %{recipient}!
+        instruction: 'Click the link below to unlock your account:'
+        message: Your account has been locked due to an excessive number of unsuccessful sign in attempts.
+        subject: Unlock instructions
+    omniauth_callbacks:
+      failure: Could not authenticate you from %{kind} because "%{reason}".
+      success: Successfully authenticated from %{kind} account.
+    passwords:
+      edit:
+        change_my_password: Change my password
+        change_your_password: Change your password
+        confirm_new_password: Confirm new password
+        new_password: New password
+      new:
+        forgot_your_password: Forgot your password?
+        send_me_reset_password_instructions: Send me reset password instructions
+      no_token: You can't access this page without coming from a password reset email. If you do come from a password reset email, please make sure you used the full URL provided.
+      send_instructions: You will receive an email with instructions on how to reset your password in a few minutes.
+      send_paranoid_instructions: If your email address exists in our database, you will receive a password recovery link at your email address in a few minutes.
+      updated: Your password has been changed successfully. You are now signed in.
+      updated_not_active: Your password has been changed successfully.
+    registrations:
+      destroyed: Bye! Your account has been successfully cancelled. We hope to see you again soon.
+      edit:
+        are_you_sure: Are you sure?
+        cancel_my_account: Cancel my account
+        currently_waiting_confirmation_for_email: 'Currently waiting confirmation for: %{email}'
+        leave_blank_if_you_don_t_want_to_change_it: leave blank if you don't want to change it
+        title: Edit %{resource}
+        unhappy: Unhappy?
+        update: Update
+        we_need_your_current_password_to_confirm_your_changes: we need your current password to confirm your changes
+      new:
+        sign_up: Sign up
+      signed_up: Welcome! You have signed up successfully.
+      signed_up_but_inactive: You have signed up successfully. However, we could not sign you in because your account is not yet activated.
+      signed_up_but_locked: You have signed up successfully. However, we could not sign you in because your account is locked.
+      signed_up_but_unconfirmed: A message with a confirmation link has been sent to your email address. Please follow the link to activate your account.
+      update_needs_confirmation: You updated your account successfully, but we need to verify your new email address. Please check your email and follow the confirm link to confirm your new email address.
+      updated: Your account has been updated successfully.
+      updated_but_not_signed_in: Your account has been updated successfully, but since your password was changed, you need to sign in again
+    sessions:
+      already_signed_out: Signed out successfully.
+      new:
+        sign_in: Log in
+      signed_in: Signed in successfully.
+      signed_out: Signed out successfully.
+    shared:
+      links:
+        back: Back
+        didn_t_receive_confirmation_instructions: Didn't receive confirmation instructions?
+        didn_t_receive_unlock_instructions: Didn't receive unlock instructions?
+        forgot_your_password: Forgot your password?
+        sign_in: Log in
+        sign_in_with_provider: Sign in with %{provider}
+        sign_up: Sign up
+      minimum_password_length:
+        one: "(%{count} character minimum)"
+        other: "(%{count} characters minimum)"
+    unlocks:
+      new:
+        resend_unlock_instructions: Resend unlock instructions
+      send_instructions: You will receive an email with instructions for how to unlock your account in a few minutes.
+      send_paranoid_instructions: If your account exists, you will receive an email with instructions for how to unlock it in a few minutes.
+      unlocked: Your account has been unlocked successfully. Please sign in to continue.
+  errors:
+    messages:
+      already_confirmed: was already confirmed, please try signing in
+      confirmation_period_expired: needs to be confirmed within %{period}, please request a new one
+      expired: has expired, please request a new one
+      not_found: not found
+      not_locked: was not locked
+      not_saved:
+        one: '1 error prohibited this %{resource} from being saved:'
+        other: "%{count} errors prohibited this %{resource} from being saved:"
diff --git a/config/locales/devise.views.es.yml b/config/locales/devise.views.es.yml
new file mode 100644
index 0000000..4a631e8
--- /dev/null
+++ b/config/locales/devise.views.es.yml
@@ -0,0 +1,146 @@
+es:
+  activerecord:
+    attributes:
+      user:
+        confirmation_sent_at: Confirmación enviada a
+        confirmation_token: Código de confirmación
+        confirmed_at: Confirmado en
+        created_at: Creado en
+        current_password: Contraseña actual
+        current_sign_in_at: Fecha del ingreso actual
+        current_sign_in_ip: IP del ingreso actual
+        email: Email
+        encrypted_password: Contraseña cifrada
+        failed_attempts: Intentos fallidos
+        last_sign_in_at: Fecha del último ingreso
+        last_sign_in_ip: IP del último inicio
+        locked_at: Fecha de bloqueo
+        password: Contraseña
+        password_confirmation: Confirmación de la contraseña
+        remember_created_at: Fecha de 'Recordarme'
+        remember_me: Recordarme
+        reset_password_sent_at: Fecha de envío de código para contraseña
+        reset_password_token: Código para restablecer contraseña
+        sign_in_count: Cantidad de ingresos
+        unconfirmed_email: Email no confirmado
+        unlock_token: Código de desbloqueo
+        updated_at: Actualizado en
+    models:
+      user:
+        one: Usuario
+        other: Usuarios
+  devise:
+    confirmations:
+      confirmed: Tu cuenta ha sido confirmada satisfactoriamente.
+      new:
+        resend_confirmation_instructions: Reenviar instrucciones de confirmación
+      send_instructions: Vas a recibir un correo con instrucciones sobre cómo confirmar tu cuenta en unos minutos.
+      send_paranoid_instructions: Si tu correo existe en nuestra base de datos, en unos minutos recibirás un correo con instrucciones sobre cómo confirmar tu cuenta.
+    failure:
+      already_authenticated: Ya has iniciado sesión.
+      inactive: Tu cuenta aún no ha sido activada.
+      invalid: "%{authentication_keys} o contraseña inválidos."
+      last_attempt: Tienes un intento más antes de que tu cuenta sea bloqueada.
+      locked: Tu cuenta está bloqueada.
+      not_found_in_database: "%{authentication_keys} o contraseña inválidos."
+      timeout: Tu sesión expiró. Por favor, inicia sesión nuevamente para continuar.
+      unauthenticated: Tienes que iniciar sesión o registrarte para poder continuar.
+      unconfirmed: Tienes que confirmar tu cuenta para poder continuar.
+    mailer:
+      confirmation_instructions:
+        action: Confirmar mi cuenta
+        greeting: "¡Bienvenido %{recipient}!"
+        instruction: 'Usted puede confirmar el correo electrónico de su cuenta a través de este enlace:'
+        subject: Instrucciones de confirmación
+      email_changed:
+        greeting: "¡Hola %{recipient}! "
+        message: Estamos contactando contigo para notificarte que tu email ha sido cambiado a %{email}.
+        subject: Email cambiado
+      password_change:
+        greeting: Hola %{recipient}!
+        message: Le estamos contactando para notificarle que su contraseña ha sido cambiada.
+        subject: Contraseña cambiada
+      reset_password_instructions:
+        action: Cambiar mi contraseña
+        greeting: "¡Hola %{recipient}!"
+        instruction: Alguien ha solicitado un enlace para cambiar su contraseña, lo que se puede realizar a través del siguiente enlace.
+        instruction_2: Si usted no lo ha solicitado, por favor ignore este correo electrónico.
+        instruction_3: Su contraseña no será cambiada hasta que usted acceda al enlace y cree una nueva.
+        subject: Instrucciones de recuperación de contraseña
+      unlock_instructions:
+        action: Desbloquear mi cuenta
+        greeting: "¡Hola %{recipient}!"
+        instruction: 'Haga click en el siguiente enlace para desbloquear su cuenta:'
+        message: Su cuenta ha sido bloqueada debido a una cantidad excesiva de intentos infructuosos para ingresar.
+        subject: Instrucciones para desbloquear
+    omniauth_callbacks:
+      failure: No has sido autorizado en la cuenta %{kind} porque "%{reason}".
+      success: Has sido autorizado satisfactoriamente en la cuenta %{kind}.
+    passwords:
+      edit:
+        change_my_password: Cambiar mi contraseña
+        change_your_password: Cambie su contraseña
+        confirm_new_password: Confirme la nueva contraseña
+        new_password: Nueva contraseña
+      new:
+        forgot_your_password: "¿Ha olvidado su contraseña?"
+        send_me_reset_password_instructions: Envíeme las instrucciones para resetear mi contraseña
+      no_token: No puedes acceder a esta página si no es a través de un enlace para resetear tu contraseña. Si has llegado hasta aquí desde el email para resetear tu contraseña, por favor asegúrate de que la URL introducida está completa.
+      send_instructions: Recibirás un correo con instrucciones sobre cómo resetear tu contraseña en unos pocos minutos.
+      send_paranoid_instructions: Si tu correo existe en nuestra base de datos, recibirás un correo con instrucciones sobre cómo resetear tu contraseña en tu bandeja de entrada.
+      updated: Se ha cambiado tu contraseña. Ya iniciaste sesión.
+      updated_not_active: Tu contraseña fue cambiada.
+    registrations:
+      destroyed: "¡Adiós! Tu cuenta ha sido cancelada correctamente. Esperamos verte pronto."
+      edit:
+        are_you_sure: "¿Está usted seguro?"
+        cancel_my_account: Anular mi cuenta
+        currently_waiting_confirmation_for_email: 'Actualmente esperando la confirmacion de: %{email} '
+        leave_blank_if_you_don_t_want_to_change_it: dejar en blanco si no desea cambiarlo
+        title: Editar %{resource}
+        unhappy: "¿Disconforme?"
+        update: Actualizar
+        we_need_your_current_password_to_confirm_your_changes: necesitamos su contraseña actual para confirmar los cambios
+      new:
+        sign_up: Registrarse
+      signed_up: Bienvenido. Tu cuenta fue creada.
+      signed_up_but_inactive: Tu cuenta ha sido creada correctamente. Sin embargo, no hemos podido iniciar la sesión porque tu cuenta aún no está activada.
+      signed_up_but_locked: Tu cuenta ha sido creada correctamente. Sin embargo, no hemos podido iniciar la sesión porque que tu cuenta está bloqueada.
+      signed_up_but_unconfirmed: Se ha enviado un mensaje con un enlace de confirmación a tu correo electrónico. Abre el enlace para activar tu cuenta.
+      update_needs_confirmation: Has actualizado tu cuenta correctamente, pero es necesario confirmar tu nuevo correo electrónico. Por favor, comprueba tu correo y sigue el enlace de confirmación para finalizar la comprobación del nuevo correo electrónico.
+      updated: Tu cuenta se ha actualizado.
+      updated_but_not_signed_in: 
+    sessions:
+      already_signed_out: Sesión finalizada.
+      new:
+        sign_in: Iniciar sesión
+      signed_in: Sesión iniciada.
+      signed_out: Sesión finalizada.
+    shared:
+      links:
+        back: Atrás
+        didn_t_receive_confirmation_instructions: "¿No ha recibido las instrucciones de confirmación?"
+        didn_t_receive_unlock_instructions: "¿No ha recibido instrucciones para desbloquear?"
+        forgot_your_password: "¿Ha olvidado su contraseña?"
+        sign_in: Iniciar sesión
+        sign_in_with_provider: Iniciar sesión con %{provider}
+        sign_up: Registrarse
+      minimum_password_length:
+        one: "(%{count} caractere como mínimo)"
+        other: "(%{count} caracteres como mínimo)"
+    unlocks:
+      new:
+        resend_unlock_instructions: Reenviar instrucciones para desbloquear
+      send_instructions: Vas a recibir instrucciones para desbloquear tu cuenta en unos pocos minutos.
+      send_paranoid_instructions: Si tu cuenta existe, vas a recibir instrucciones para desbloquear tu cuenta en unos pocos minutos.
+      unlocked: Tu cuenta ha sido desbloqueada. Ya puedes iniciar sesión.
+  errors:
+    messages:
+      already_confirmed: ya ha sido confirmada, por favor intenta iniciar sesión
+      confirmation_period_expired: necesita confirmarse dentro de %{period}, por favor solicita una nueva
+      expired: ha expirado, por favor solicita una nueva
+      not_found: no se ha encontrado
+      not_locked: no estaba bloqueada
+      not_saved:
+        one: 'Ocurrió un error al tratar de guardar %{resource}:'
+        other: 'Ocurrieron %{count} errores al tratar de guardar %{resource}:'
diff --git a/doc/autenticacion.md b/doc/autenticacion.md
new file mode 100644
index 0000000..b83ed84
--- /dev/null
+++ b/doc/autenticacion.md
@@ -0,0 +1,23 @@
+# Autenticación de usuaries
+
+Estamos pasando de un modelo integrado donde Usuarias son usuaries de
+una red IMAP e Invitadxs son usuaries locales de la plataforma, a una
+más "monolítica" donde las cuentas se gestionan desde la plataforma
+misma.
+
+Entonces, Usuaria e Invitadx se fusionan y su diferencia es solo de
+privilegios sobre un sitio (puede hacer todo / solo puede cargar
+artículos y modificar los propios).
+
+No nos gusta la idea de implementar todo un sistema de privilegios,
+primero porque queremos que Sutty sea una plataforma democrática y
+segundo porque en nuestra experiencia nadie los usa y prefieren usar una
+cuenta de administración.
+
+La migración a Devise nos va a permitir tener recuperación de
+contraseñas, registro independiente, correos de bienvenida y varias
+cosas más.
+
+Planeamos que Sutty también sea un proveedor de oAuth, para poder
+integrarla con otras plataformas comunitarias
+(rocket.chat/mattermost.com principalmente).