diff --git a/app/models/problem.rb b/app/models/problem.rb
index 55403fa..928fc41 100644
--- a/app/models/problem.rb
+++ b/app/models/problem.rb
@@ -160,6 +160,7 @@ class Problem
     Rails.application.routes.url_helpers.app_problem_url(
       app,
       self,
+      protocol: Errbit::Config.protocol,
       host: Errbit::Config.host,
       port: Errbit::Config.port
     )
diff --git a/spec/models/problem_spec.rb b/spec/models/problem_spec.rb
index 9ed1dab..ba3d0c5 100644
--- a/spec/models/problem_spec.rb
+++ b/spec/models/problem_spec.rb
@@ -475,4 +475,26 @@ describe Problem, type: 'model' do
       end
     end
   end
+
+  context "#url" do
+    subject { Fabricate(:problem) }
+
+    it "uses the configured protocol" do
+      allow(Errbit::Config).to receive(:protocol).and_return("https")
+
+      expect(subject.url).to eq "https://errbit.example.com/apps/#{subject.app.id}/problems/#{subject.id}"
+    end
+
+    it "uses the configured host" do
+      allow(Errbit::Config).to receive(:host).and_return("memyselfandi.com")
+
+      expect(subject.url).to eq "http://memyselfandi.com/apps/#{subject.app.id}/problems/#{subject.id}"
+    end
+
+    it "uses the configured port" do
+      allow(Errbit::Config).to receive(:port).and_return(8123)
+
+      expect(subject.url).to eq "http://errbit.example.com:8123/apps/#{subject.app.id}/problems/#{subject.id}"
+    end
+  end
 end
--
libgit2 0.21.2