diff --git a/app/models/user.rb b/app/models/user.rb
index a3d5efae234784070fab14b15e00602f35fee525..989e2c05a40ee1d1a645187150c37629a58f9ba7 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -63,7 +63,7 @@ class User < ApplicationRecord
   end
 
   def cleanup_languages
-    self.languages_from = self.languages_from.gsub(/\s+/, '').downcase
-    self.languages_to = self.languages_to.gsub(/\s+/, '').downcase
+    self.languages_from = self.languages_from&.gsub(/\s+/, '')&.downcase
+    self.languages_to = self.languages_to&.gsub(/\s+/, '')&.downcase
   end
 end
diff --git a/db/seeds.rb b/db/seeds.rb
index 329fa7b2e6f5259395c3187ac6972dbecb2203e6..b1d241e05d962d8d7bf0b6ff1fb33dd2c53f9d2d 100644
--- a/db/seeds.rb
+++ b/db/seeds.rb
@@ -46,7 +46,7 @@ Conference.find_or_create_by!(slug: "37c3") do |c|
   c.location = "Congress Center Hamburg"
 end
 
-Conference.find_or_create_by!(slug: "38c3").tap do |c|
+Conference.find_or_create_by!(slug: "38c3") do |c|
   c.name = "38th Chaos Communication Congress (de-en)"
   c.time_zone = "Berlin"
   c.starts_at = DateTime.parse("27 December 2024 10:30 CET")
@@ -59,7 +59,7 @@ Conference.find_or_create_by!(slug: "38c3").tap do |c|
   c.save!
 end
 
-Conference.find_or_create_by!(slug: "38c3-more").tap do |c|
+Conference.find_or_create_by!(slug: "38c3-more") do |c|
   c.name = "38th Chaos Communication Congress (more languages)"
   c.time_zone = "Berlin"
   c.starts_at = DateTime.parse("27 December 2024 10:30 CET")
@@ -74,7 +74,7 @@ end
 
 if Rails.env.development?
   %w[coverage fog comedy adjust forge fail vigorous promise chemistry conception meat storage certain warm develop civilian cousin injection hammer health appetite conventional good snake grant suspect atmosphere linen wrong deal calf sea management silence watch nuance loan quit convert failure bracket slice sweat treaty plot still chimpanzee assume functional marsh dream mail state dorm kid formation secular agile beach guide salesperson merit goalkeeper incongruous cart pig joystick regulation apparatus myth patent glue behead flu departure spectrum parking indication delay hesitate viable lay treat cooperative sensation auction sphere stain tap pass].each do |username|
-    User.find_or_create_by(name: username).tap do |u|
+    User.find_or_create_by(name: username) do |u|
       u.email = "c3lingo+#{username}@x.moeffju.net"
       u.invitation_token = "gargamel"
       u.save!