diff --git a/lib/raven/interfaces/stack_trace.rb b/lib/raven/interfaces/stack_trace.rb
index 90b9bdc37..e42807153 100644
--- a/lib/raven/interfaces/stack_trace.rb
+++ b/lib/raven/interfaces/stack_trace.rb
@@ -35,16 +35,19 @@ class Frame < Interface
       def filename
         return nil if self.abs_path.nil?
 
-        prefix = $LOAD_PATH.select { |s| self.abs_path.start_with?(s.to_s) }.sort_by { |s| s.to_s.length }.last
-        if prefix.nil? && Raven.configuration.project_root
-          project_root = Raven.configuration.project_root.to_s
-          if self.abs_path.start_with?(project_root)
-            prefix = project_root
-          end
+        prefix = if project_root && self.abs_path.start_with?(project_root)
+          project_root
+        else
+          $LOAD_PATH.select { |s| self.abs_path.start_with?(s.to_s) }.sort_by { |s| s.to_s.length }.last
         end
+
         prefix ? self.abs_path[prefix.to_s.chomp(File::SEPARATOR).length+1..-1] : self.abs_path
       end
 
+      def project_root
+        @project_root ||= Raven.configuration.project_root && Raven.configuration.project_root.to_s
+      end
+
       def to_hash(*args)
         data = super(*args)
         data[:filename] = self.filename
diff --git a/spec/raven/event_spec.rb b/spec/raven/event_spec.rb
index fd0308cdc..01dc05fa9 100644
--- a/spec/raven/event_spec.rb
+++ b/spec/raven/event_spec.rb
@@ -368,7 +368,6 @@ class SubExc < BaseExc; end
       end
 
       context 'in a rails environment' do
-
         before do
           rails = double('Rails')
           allow(rails).to receive(:root) { '/rails/root' }
@@ -384,7 +383,7 @@ class SubExc < BaseExc; end
             allow(e).to receive(:backtrace).and_return([
               "/rails/root/vendor/bundle/cache/other_gem.rb:10:in `public_method'",
               "vendor/bundle/some_gem.rb:10:in `a_method'",
-              "/rails/root/app/foobar:132:in `new_function'",
+              "/rails/root/app/models/user.rb:132:in `new_function'",
               "/gem/lib/path:87:in `a_function'",
               "/app/some/other/path:1412:in `other_function'",
               "test/some/other/path:1412:in `other_function'"
@@ -401,13 +400,28 @@ class SubExc < BaseExc; end
             expect(frames[1][:in_app]).to eq(false)
             expect(frames[2][:filename]).to eq("/gem/lib/path")
             expect(frames[2][:in_app]).to eq(false)
-            expect(frames[3][:filename]).to eq("app/foobar")
+            expect(frames[3][:filename]).to eq("app/models/user.rb")
             expect(frames[3][:in_app]).to eq(true)
             expect(frames[4][:filename]).to eq("vendor/bundle/some_gem.rb")
             expect(frames[4][:in_app]).to eq(false)
             expect(frames[5][:filename]).to eq("vendor/bundle/cache/other_gem.rb")
             expect(frames[5][:in_app]).to eq(false)
           end
+
+          context 'when a path under project_root is on the load path' do
+            before do
+              $LOAD_PATH << '/rails/root/app/models'
+            end
+
+            after do
+              $LOAD_PATH.delete('/rails/root/app/models')
+            end
+
+            it "doesn't remove any path information under project_root" do
+              frames = hash[:exception][:stacktrace][:frames]
+              expect(frames[3][:filename]).to eq("app/models/user.rb")
+            end
+          end
         end
       end