diff --git a/app/models/condition.rb b/app/models/condition.rb
index ef0d79cca..fd1379300 100644
--- a/app/models/condition.rb
+++ b/app/models/condition.rb
@@ -28,9 +28,9 @@
 class Condition < ApplicationRecord
   belongs_to :question
   enum action_type: %i[remove add_webhook]
-  serialize :option_list, Array
-  serialize :remove_data, Array
-  serialize :webhook_data, JSON
+  serialize :option_list, type: Array
+  serialize :remove_data, type: Array
+  serialize :webhook_data, coder: JSON
 
   # Sort order: Number ASC
   default_scope { order(number: :asc) }
diff --git a/app/models/org.rb b/app/models/org.rb
index 2f7aa76bb..92122900e 100644
--- a/app/models/org.rb
+++ b/app/models/org.rb
@@ -54,7 +54,7 @@ class Org < ApplicationRecord
   # The links are validated against custom validator allocated at
   # validators/template_links_validator.rb
   attribute :links, :text, default: { org: [] }
-  serialize :links, JSON
+  serialize :links, coder: JSON
 
   # ================
   # = Associations =
diff --git a/app/models/pref.rb b/app/models/pref.rb
index 01f83ee17..65af0fedc 100644
--- a/app/models/pref.rb
+++ b/app/models/pref.rb
@@ -13,7 +13,7 @@
 class Pref < ApplicationRecord
   ##
   # Serialize prefs to JSON
-  serialize :settings, JSON
+  serialize :settings, coder: JSON
 
   # ================
   # = Associations =
diff --git a/app/models/stat_created_plan.rb b/app/models/stat_created_plan.rb
index 6ba26d227..4c2c7f2c1 100644
--- a/app/models/stat_created_plan.rb
+++ b/app/models/stat_created_plan.rb
@@ -19,7 +19,7 @@
 
 # Object that represents a Nbr of Plans created usage statistic
 class StatCreatedPlan < Stat
-  serialize :details, JSON
+  serialize :details, coder: JSON
 
   def by_template
     parse_details.fetch('by_template', [])
diff --git a/app/models/template.rb b/app/models/template.rb
index 6cbb3c3e4..4e83978b6 100644
--- a/app/models/template.rb
+++ b/app/models/template.rb
@@ -53,7 +53,7 @@ class Template < ApplicationRecord
   # The links is validated against custom validator allocated at
   # validators/template_links_validator.rb
   attribute :links, :text, default: { funder: [], sample_plan: [] }
-  serialize :links, JSON
+  serialize :links, coder: JSON
 
   attribute :published, :boolean, default: false
   attribute :archived, :boolean, default: false
diff --git a/app/models/user.rb b/app/models/user.rb
index c3ff35796..4d93247c4 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -70,7 +70,7 @@ class User < ApplicationRecord
 
   ##
   # User Notification Preferences
-  serialize :prefs, Hash
+  serialize :prefs, type: Hash
 
   # default user language to the default language
   attribute :language_id, :integer, default: -> { Language.default&.id }
diff --git a/config/environments/test.rb b/config/environments/test.rb
index 179bb104b..122ad051b 100644
--- a/config/environments/test.rb
+++ b/config/environments/test.rb
@@ -31,7 +31,7 @@
   config.action_controller.perform_caching = false
 
   # Raise exceptions instead of rendering exception templates.
-  config.action_dispatch.show_exceptions = false
+  config.action_dispatch.show_exceptions = :none
 
   # Disable request forgery protection in test environment.
   config.action_controller.allow_forgery_protection = false