diff --git a/lib/accountify/contact.rb b/app/domains/accountify/contact.rb
similarity index 100%
rename from lib/accountify/contact.rb
rename to app/domains/accountify/contact.rb
diff --git a/lib/accountify/error.rb b/app/domains/accountify/error.rb
similarity index 100%
rename from lib/accountify/error.rb
rename to app/domains/accountify/error.rb
diff --git a/lib/accountify/invoice.rb b/app/domains/accountify/invoice.rb
similarity index 100%
rename from lib/accountify/invoice.rb
rename to app/domains/accountify/invoice.rb
diff --git a/lib/accountify/invoice_status_summary.rb b/app/domains/accountify/invoice_status_summary.rb
similarity index 100%
rename from lib/accountify/invoice_status_summary.rb
rename to app/domains/accountify/invoice_status_summary.rb
diff --git a/lib/accountify/models/contact.rb b/app/domains/accountify/models/contact.rb
similarity index 100%
rename from lib/accountify/models/contact.rb
rename to app/domains/accountify/models/contact.rb
diff --git a/lib/accountify/models/invoice.rb b/app/domains/accountify/models/invoice.rb
similarity index 100%
rename from lib/accountify/models/invoice.rb
rename to app/domains/accountify/models/invoice.rb
diff --git a/lib/accountify/models/invoice_status_summary.rb b/app/domains/accountify/models/invoice_status_summary.rb
similarity index 100%
rename from lib/accountify/models/invoice_status_summary.rb
rename to app/domains/accountify/models/invoice_status_summary.rb
diff --git a/lib/accountify/models/organisation.rb b/app/domains/accountify/models/organisation.rb
similarity index 100%
rename from lib/accountify/models/organisation.rb
rename to app/domains/accountify/models/organisation.rb
diff --git a/lib/accountify/not_available.rb b/app/domains/accountify/not_available.rb
similarity index 100%
rename from lib/accountify/not_available.rb
rename to app/domains/accountify/not_available.rb
diff --git a/lib/accountify/not_found.rb b/app/domains/accountify/not_found.rb
similarity index 100%
rename from lib/accountify/not_found.rb
rename to app/domains/accountify/not_found.rb
diff --git a/lib/accountify/organisation.rb b/app/domains/accountify/organisation.rb
similarity index 100%
rename from lib/accountify/organisation.rb
rename to app/domains/accountify/organisation.rb
diff --git a/app/models/event.rb b/app/models/event.rb
new file mode 100644
index 0000000..dbc5573
--- /dev/null
+++ b/app/models/event.rb
@@ -0,0 +1,19 @@
+class Event < ActiveRecord::Base
+  self.table_name = 'events'
+
+  # associations
+
+  belongs_to :eventable, polymorphic: true
+
+  # validations
+
+  validates :user_id, presence: true
+  validates :tenant_id, presence: true
+
+  validates :type, presence: true, length: { maximum: 255 }
+
+  validates :eventable_type, presence: true, length: { maximum: 255 },
+    if: -> { eventable_id.present? }
+
+  validates :eventable_id, presence: true, if: -> { eventable_type.present? }
+end
diff --git a/db/migrate/20240114120424_create_events.rb b/db/migrate/20240114120424_create_events.rb
index a0545bd..b7b82a5 100644
--- a/db/migrate/20240114120424_create_events.rb
+++ b/db/migrate/20240114120424_create_events.rb
@@ -4,16 +4,13 @@ def change
       t.bigint :user_id, null: false
       t.bigint :tenant_id, null: false
 
-      t.text :type, null: false
-
-      t.text :eventable_type, null: false
-      t.bigint :eventable_id, null: false
-
+      t.string :type, null: false, limit: 255
       t.jsonb :body
-
       t.datetime :created_at, null: false
-    end
 
-    add_index :events, [:eventable_type, :eventable_id]
+      t.string :eventable_type, null: false, limit: 255
+      t.bigint :eventable_id, null: false
+      t.index [:eventable_type, :eventable_id]
+    end
   end
 end
diff --git a/lib/event.rb b/lib/event.rb
deleted file mode 100644
index 8269f43..0000000
--- a/lib/event.rb
+++ /dev/null
@@ -1,12 +0,0 @@
-class Event < ActiveRecord::Base
-  self.table_name = 'events'
-
-  # validations
-
-  validates :user_id, :tenant_id, presence: true
-  validates :eventable_type, :eventable_id, presence: true
-
-  # associations
-
-  belongs_to :eventable, polymorphic: true
-end