diff --git a/lib/factory_bot_rails/railtie.rb b/lib/factory_bot_rails/railtie.rb
index 2e9cd81..8dca2f4 100644
--- a/lib/factory_bot_rails/railtie.rb
+++ b/lib/factory_bot_rails/railtie.rb
@@ -18,12 +18,9 @@ module FactoryBotRails
       FactoryBot.definition_file_paths = definition_file_paths
     end
 
-    initializer "factory_bot.register_reloader" do |app|
-      Reloader.new(app, config).run
-    end
-
-    config.after_initialize do
-      FactoryBot.reload
+    config.after_initialize do |app|
+      FactoryBot.find_definitions
+      Reloader.new(app).run
     end
 
     private
diff --git a/lib/factory_bot_rails/reloader.rb b/lib/factory_bot_rails/reloader.rb
index dacb94c..57d13d7 100644
--- a/lib/factory_bot_rails/reloader.rb
+++ b/lib/factory_bot_rails/reloader.rb
@@ -4,9 +4,8 @@ require "factory_bot_rails/definition_file_paths"
 
 module FactoryBotRails
   class Reloader
-    def initialize(app, config)
+    def initialize(app)
       @app = app
-      @config = config
       @paths = DefinitionFilePaths.new(FactoryBot.definition_file_paths)
     end
 
@@ -18,7 +17,7 @@ module FactoryBotRails
 
     private
 
-    attr_reader :app, :config
+    attr_reader :app
 
     def build_reloader
       reloader_class.new(@paths.files, @paths.directories) do
@@ -31,12 +30,8 @@ module FactoryBotRails
     end
 
     def register_reloader(reloader)
-      closed_over_app = app
-
-      config.to_prepare do
-        if closed_over_app.initialized?
-          reloader.execute
-        end
+      app.reloader.to_prepare do
+        reloader.execute
       end
 
       app.reloaders << reloader
diff --git a/spec/factory_bot_rails/reloader_spec.rb b/spec/factory_bot_rails/reloader_spec.rb
index 70010d1..30ef75d 100644
--- a/spec/factory_bot_rails/reloader_spec.rb
+++ b/spec/factory_bot_rails/reloader_spec.rb
@@ -12,42 +12,74 @@ describe FactoryBotRails::Reloader do
 
     context "when a definition file paths exist" do
       it "registers a reloader" do
-        allow(reloader_class).to receive(:new)
+        file_watcher = file_watcher_double
 
-        run_reloader(["spec/fixtures/factories", "not_exist_directory"])
+        run_reloader(
+          ["spec/fixtures/factories", "not_exist_directory"],
+          file_watcher
+        )
 
-        expect(reloader_class).to have_received(:new)
+        expect(file_watcher).to have_received(:new)
       end
     end
 
     context "when a file exists but not a directory" do
       it "registers a reloader" do
-        allow(reloader_class).to receive(:new)
+        file_watcher = file_watcher_double
 
-        run_reloader(["spec/fake_app", "not_exist_directory"])
+        run_reloader(
+          ["spec/fake_app", "not_exist_directory"],
+          file_watcher
+        )
 
-        expect(reloader_class).to have_received(:new)
+        expect(file_watcher).to have_received(:new)
       end
     end
 
     context "when a definition file paths NOT exist" do
       it "does NOT register a reloader" do
-        allow(reloader_class).to receive(:new)
+        file_watcher = file_watcher_double
 
-        run_reloader(["not_exist_directory"])
+        run_reloader(["not_exist_directory"], file_watcher)
 
-        expect(reloader_class).not_to have_received(:new)
+        expect(file_watcher).not_to have_received(:new)
       end
     end
 
-    def run_reloader(definition_file_paths)
+    def run_reloader(definition_file_paths, file_watcher)
       FactoryBot.definition_file_paths = definition_file_paths
-      FactoryBotRails::Reloader
-        .new(Rails.application, Rails.application.config).run
+      app = app_double(file_watcher)
+      FactoryBotRails::Reloader.new(app).run
     end
 
-    def reloader_class
-      Rails.application.config.file_watcher
+    def file_watcher_double
+      class_double(
+        Rails.application.config.file_watcher,
+        new: double(:reloader, execute: nil)
+      )
+    end
+
+    def app_double(file_watcher)
+      instance_double(
+        Rails.application.class,
+        config: app_config_double(file_watcher),
+        reloader: reloader_double,
+        reloaders: []
+      )
+    end
+
+    def app_config_double(file_watcher)
+      instance_double(
+        Rails.application.config.class,
+        file_watcher: file_watcher
+      )
+    end
+
+    def reloader_double
+      class_double(
+        Rails.application.reloader,
+        to_prepare: nil
+      )
     end
   end
 end