diff --git a/.gitignore b/.gitignore
index 3c2860b..3a7bf6a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,6 +3,6 @@ pkg/
 .idea/*
 *.db
 tmp/fixture_builder.yml
-test/fixtures/magical_creatures.yml
+test/fixtures/*.yml
 Gemfile.lock
 *.gem
diff --git a/Rakefile b/Rakefile
index 568b3ba..ad9cb94 100644
--- a/Rakefile
+++ b/Rakefile
@@ -3,9 +3,29 @@ include Rake::DSL if defined?(Rake::DSL)
 Bundler::GemHelper.install_tasks
 
 require 'rake/testtask'
-Rake::TestTask.new(:test) do |t|
+Rake::TestTask.new(:run_test) do |t|
   t.test_files = FileList['test/*_test.rb']
   t.verbose = false
 end
 
+task :test do
+  begin
+    Rake::Task[:run_test].execute
+  ensure
+    Rake::Task[:dbdrop].invoke
+  end
+end
+
+require 'pg'
+task :dbcreate do
+  PG.connect(dbname: 'postgres').exec("CREATE DATABASE testdb")
+end
+
+task :dbdrop do
+  PG.connect(dbname: 'postgres').exec("DROP DATABASE testdb")
+end
+
+task :test => :dbcreate
+
+
 task :default => :test
diff --git a/fixture_builder.gemspec b/fixture_builder.gemspec
index 34c7013..14e89ed 100644
--- a/fixture_builder.gemspec
+++ b/fixture_builder.gemspec
@@ -29,5 +29,5 @@ Gem::Specification.new do |s|
   s.add_development_dependency %q{rake}
   s.add_development_dependency %q{rails}, '>= 2'
   s.add_development_dependency %q{test-unit}
-  s.add_development_dependency %q{sqlite3}
+  s.add_development_dependency %q{pg}
 end
diff --git a/lib/fixture_builder/builder.rb b/lib/fixture_builder/builder.rb
index 83e5d9a..28c37aa 100644
--- a/lib/fixture_builder/builder.rb
+++ b/lib/fixture_builder/builder.rb
@@ -91,13 +91,25 @@ def dump_empty_fixtures_for_all_tables
       end
     end
 
+    def klass_by_table_name
+      @klass_by_table_name ||= ActiveRecord::Base
+                                   .descendants
+                                   .reject(&:abstract_class)
+                                   .group_by(&:table_name)
+                                   .transform_values { |klasses| klasses.min { |klass| klass.ancestors.size } }
+    end
+
+    def eligible_for_serialization(table_klass)
+      table_klass && table_klass < ActiveRecord::Base && table_klass.attribute_names.include?('id')
+    end
+
     def dump_tables
       default_date_format = Date::DATE_FORMATS[:default]
       Date::DATE_FORMATS[:default] = Date::DATE_FORMATS[:db]
       begin
         fixtures = tables.inject([]) do |files, table_name|
-          table_klass = table_name.classify.constantize rescue nil
-          if table_klass && table_klass < ActiveRecord::Base
+          table_klass = klass_by_table_name[table_name] rescue nil
+          if eligible_for_serialization(table_klass)
             rows = table_klass.unscoped do
               table_klass.order(:id).all.collect do |obj|
                 attrs = obj.attributes.select { |attr_name| table_klass.column_names.include?(attr_name) }
diff --git a/test/fixture_builder_test.rb b/test/fixture_builder_test.rb
index eac005d..481070c 100644
--- a/test/fixture_builder_test.rb
+++ b/test/fixture_builder_test.rb
@@ -53,6 +53,58 @@ def test_serialization
     assert_equal "---\n- shading\n- rooting\n- seeding\n", generated_fixture['enty']['powers']
   end
 
+  def test_sti_serialization
+    create_and_blow_away_old_db
+    force_fixture_generation
+
+    FixtureBuilder.configure do |fbuilder|
+      fbuilder.files_to_check += Dir[test_path("*.rb")]
+      fbuilder.factory do
+        @argus = MythicalCreature.create(name: 'Argus',
+                                         species: 'giant',
+                                         powers: %w[watching seeing])
+      end
+    end
+    generated_fixture = YAML.load(File.open(test_path("fixtures/magical_creatures.yml")))
+    assert_equal "---\n- watching\n- seeing\n", generated_fixture['argus']['powers']
+    assert_equal 'MythicalCreature', generated_fixture['argus']['type']
+  end
+
+  def test_namespace_serialization
+    create_and_blow_away_old_db
+    force_fixture_generation
+
+    powers = { 'super' => 'flying', 'normal' => 'galloping' }
+
+    FixtureBuilder.configure do |fbuilder|
+      fbuilder.files_to_check += Dir[test_path("*.rb")]
+      fbuilder.factory do
+        @pegasos = Legendary::Creature.create(name: 'Pegasos',
+                                              species: 'wingedhorse',
+                                              powers: powers)
+      end
+    end
+    generated_fixture = YAML.load(File.open(test_path("fixtures/my_creatures.yml")))
+    assert_equal powers, generated_fixture['pegasos']['powers']
+  end
+
+  def test_idless_serialization
+    create_and_blow_away_old_db
+    force_fixture_generation
+
+    FixtureBuilder.configure do |fbuilder|
+      fbuilder.files_to_check += Dir[test_path("*.rb")]
+      fbuilder.factory do
+        @enty = MagicalCreature.create(:name => 'Enty', :species => 'ent')
+        @king_of_gnomes = MagicalCreature.create(:name => 'robert', :species => 'gnome')
+        @relationship = CreatureRelationship.create(one: @enty, other: @king_of_gnomes)
+      end
+    end
+    generated_fixture = YAML.load(File.open(test_path("fixtures/creature_relationships.yml")))
+    assert_equal 1, generated_fixture['creature_relationships_001']['one_id']
+    assert_equal 2, generated_fixture['creature_relationships_001']['other_id']
+  end
+
   def test_do_not_include_virtual_attributes
     create_and_blow_away_old_db
     force_fixture_generation
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 778720a..332ee4d 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -24,7 +24,7 @@ def create_fixtures(*table_names, &block)
   Fixtures.create_fixtures(ActiveSupport::TestCase.fixture_path, table_names, {}, &block)
 end
 
-require 'sqlite3'
+require 'pg'
 require 'fixture_builder'
 
 class MagicalCreature < ActiveRecord::Base
@@ -40,19 +40,62 @@ class MagicalCreature < ActiveRecord::Base
   end
 end
 
+
+module Legendary
+  class Creature < ActiveRecord::Base
+    self.table_name = 'my_creatures'
+    validates_presence_of :name, :species
+
+    if ActiveRecord::VERSION::MAJOR >= 4
+      default_scope -> { where(deleted: false) }
+
+      attribute :virtual, ActiveRecord::Type::Integer.new
+    else
+      default_scope conditions: { deleted: false }
+    end
+  end
+end
+
+class MythicalCreature < MagicalCreature
+end
+
+class CreatureRelationship < ActiveRecord::Base
+  belongs_to :one, class_name: 'MagicalCreature'
+  belongs_to :other, class_name: 'MagicalCreature'
+end
+
 def create_and_blow_away_old_db
-  ActiveRecord::Base.configurations['test'] = {
-      'adapter' => 'sqlite3',
-      'database' => 'test.db'
+  ActiveRecord::Base.configurations = {
+      test: {
+          :adapter => 'postgresql',
+          :database => 'testdb',
+          :encoding => 'utf8',
+          :pool => 5
+      }
   }
+
   ActiveRecord::Base.establish_connection(:test)
 
   ActiveRecord::Base.connection.create_table(:magical_creatures, :force => true) do |t|
     t.column :name, :string
+    t.column :type, :string
     t.column :species, :string
     t.column :powers, :string
     t.column :deleted, :boolean, :default => false, :null => false
   end
+
+  ActiveRecord::Base.connection.create_table(:my_creatures, force: true) do |t|
+    t.column :name, :string
+    t.column :type, :string
+    t.column :species, :string
+    t.column :powers, :jsonb
+    t.column :deleted, :boolean, :default => false, :null => false
+  end
+
+  ActiveRecord::Base.connection.create_table(:creature_relationships, force: true, id: false) do |t|
+    t.column :one_id, :integer
+    t.column :other_id, :integer
+  end
 end
 
 def force_fixture_generation