Assisted-by: GLM-5.1 via pi

diff --git a/lib/app.rb b/lib/app.rb
index c130264..09938f0 100644
--- a/lib/app.rb
+++ b/lib/app.rb
@@ -1,11 +1,18 @@
 # frozen_string_literal: true
 
 require "roda"
+require_relative "views/layout"
 
 class App < Roda
   route do |r|
     r.root do
-      "ok"
+      render_with_layout { "ok" }
     end
   end
+
+  private
+
+  def render_with_layout(&block)
+    Views::Layout.new(&block).call
+  end
 end
diff --git a/lib/views/layout.rb b/lib/views/layout.rb
new file mode 100644
index 0000000..5b0782a
--- /dev/null
+++ b/lib/views/layout.rb
@@ -0,0 +1,27 @@
+# frozen_string_literal: true
+
+require "phlex"
+
+module Views
+end
+
+class Views::Layout < Phlex::HTML
+  def initialize(title: "Domus", &content)
+    @title = title
+    @content = content
+  end
+
+  def view_template
+    doctype
+
+    html(lang: "en") do
+      head do
+        title { @title }
+      end
+
+      body do
+        yield
+      end
+    end
+  end
+end
diff --git a/test/test_app.rb b/test/test_app.rb
index 81dd232..c6c7065 100644
--- a/test/test_app.rb
+++ b/test/test_app.rb
@@ -14,6 +14,7 @@ class TestApp < Minitest::Test
   def test_root
     get "/"
     assert_equal 200, last_response.status
-    assert_equal "ok", last_response.body
+    assert_includes last_response.body, "<title>Domus</title>"
+    assert_includes last_response.body, "ok"
   end
 end