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diff --git a/app/models/concerns/safely_change_column_default.rb b/app/models/concerns/safely_change_column_default.rb
new file mode 100644
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+++ b/app/models/concerns/safely_change_column_default.rb
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+# frozen_string_literal: true
+
+# == SafelyChangeColumnDefault concern.
+#
+# Contains functionality that allows safely changing a column default without downtime.
+# Without this concern, Rails can mutate the old default value to the new default value if the old default is explicitly
+# specified.
+#
+# Usage:
+#
+#   class SomeModel < ApplicationRecord
+#     include SafelyChangeColumnDefault
+#
+#     columns_changing_default :value
+#   end
+#
+#   # Assume a default of 100 for value
+#   SomeModel.create!(value: 100) # INSERT INTO some_model (value) VALUES (100)
+#   change_column_default('some_model', 'value', from: 100, to: 101)
+#   SomeModel.create!(value: 100) # INSERT INTO some_model (value) VALUES (100)
+#   # Without this concern, would be INSERT INTO some_model (value) DEFAULT VALUES and would insert 101.
+module SafelyChangeColumnDefault
+  extend ActiveSupport::Concern
+
+  class_methods do
+    # Indicate that one or more columns will have their database default change.
+    #
+    # By indicating those columns here, this helper prevents a case where explicitly writing the old database default
+    # will be mutated to the new database default.
+    def columns_changing_default(*columns)
+      self.columns_with_changing_default = columns.map(&:to_s)
+    end
+  end
+
+  included do
+    class_attribute :columns_with_changing_default, default: []
+
+    before_create do
+      columns_with_changing_default.to_a.each do |attr_name|
+        attr = @attributes[attr_name]
+
+        attribute_will_change!(attr_name) if !attr.changed? && attr.came_from_user?
+      end
+    end
+  end
+end