diff --git a/lib/hamlit.rb b/lib/hamlit.rb
index 1b32562f..6dde93ef 100644
--- a/lib/hamlit.rb
+++ b/lib/hamlit.rb
@@ -1,5 +1,4 @@
 require 'hamlit/engine'
-require 'hamlit/helpers'
 require 'hamlit/template'
 require 'hamlit/version'
 
diff --git a/lib/hamlit/attribute.rb b/lib/hamlit/attribute.rb
new file mode 100644
index 00000000..91f3f3d3
--- /dev/null
+++ b/lib/hamlit/attribute.rb
@@ -0,0 +1,29 @@
+require 'hamlit/concerns/attribute_builder'
+
+# Hamlit::Attribute is a module to compile old-style attributes which
+# can be compiled only on runtime. If you write old-style attributes
+# which is not valid as Ruby hash, the attributes are compiled on runtime.
+#
+# Note that you should avoid writing such a template for performance.
+module Hamlit
+  class Attribute
+    include Concerns::AttributeBuilder
+
+    def self.build(quote, attributes)
+      builder = self.new(quote)
+      builder.build(attributes)
+    end
+
+    def initialize(quote)
+      @quote = quote
+    end
+
+    def build(attributes)
+      result = ''
+      flatten_attributes(attributes).each do |key, value|
+        result += " #{key}=#{@quote}#{value}#{@quote}"
+      end
+      result
+    end
+  end
+end
diff --git a/lib/hamlit/compilers/attributes.rb b/lib/hamlit/compilers/attributes.rb
index 681c6820..0beabae3 100644
--- a/lib/hamlit/compilers/attributes.rb
+++ b/lib/hamlit/compilers/attributes.rb
@@ -10,7 +10,7 @@ module Hamlit
       include Compilers::OldAttribute
 
       included do
-        define_options :format
+        define_options :format, :attr_quote
       end
 
       def on_haml_attrs(*attrs)
diff --git a/lib/hamlit/compilers/old_attribute.rb b/lib/hamlit/compilers/old_attribute.rb
index 5acf8968..fe567a36 100644
--- a/lib/hamlit/compilers/old_attribute.rb
+++ b/lib/hamlit/compilers/old_attribute.rb
@@ -1,3 +1,5 @@
+require 'hamlit/attribute'
+require 'hamlit/concerns/attribute_builder'
 require 'hamlit/concerns/balanceable'
 require 'hamlit/concerns/ripperable'
 
@@ -6,9 +8,13 @@ require 'hamlit/concerns/ripperable'
 module Hamlit
   module Compilers
     module OldAttribute
+      include Concerns::AttributeBuilder
       include Concerns::Balanceable
+      include Concerns::Ripperable
 
       def compile_old_attribute(str)
+        return runtime_build(str) unless Ripper.sexp(str)
+
         attrs = parse_old_attributes(str)
         flatten_attributes(attrs).map do |key, value|
           next true_attribute(key) if value == 'true'
@@ -40,22 +46,6 @@ module Hamlit
         attributes
       end
 
-      def flatten_attributes(attributes)
-        flattened = {}
-
-        attributes.each do |key, value|
-          case value
-          when Hash
-            flatten_attributes(value).each do |k, v|
-              flattened["#{key}-#{k}"] = v
-            end
-          else
-            flattened[key] = value
-          end
-        end
-        flattened
-      end
-
       def read_hash_key!(tokens)
         skip_tokens!(tokens, :on_sp)
 
@@ -92,6 +82,13 @@ module Hamlit
         raise SyntaxError unless type == :on_op && str == '=>'
       end
 
+      def runtime_build(str)
+        str = str.gsub(/(\A\{|\}\Z)/, '')
+        quote = options[:attr_quote].inspect
+        code = "::Hamlit::Attribute.build(#{quote}, #{str})"
+        [[:dynamic, code]]
+      end
+
       def split_hash(str)
         columns = HashParser.assoc_columns(str)
         columns = reject_nested_columns(str, columns)
diff --git a/lib/hamlit/concerns/attribute_builder.rb b/lib/hamlit/concerns/attribute_builder.rb
new file mode 100644
index 00000000..27d6def4
--- /dev/null
+++ b/lib/hamlit/concerns/attribute_builder.rb
@@ -0,0 +1,21 @@
+module Hamlit
+  module Concerns
+    module AttributeBuilder
+      def flatten_attributes(attributes)
+        flattened = {}
+
+        attributes.each do |key, value|
+          case value
+          when Hash
+            flatten_attributes(value).each do |k, v|
+              flattened["#{key}-#{k}"] = v
+            end
+          else
+            flattened[key] = value
+          end
+        end
+        flattened
+      end
+    end
+  end
+end
diff --git a/spec/hamlit/engine/old_attributs_spec.rb b/spec/hamlit/engine/old_attributes_spec.rb
similarity index 89%
rename from spec/hamlit/engine/old_attributs_spec.rb
rename to spec/hamlit/engine/old_attributes_spec.rb
index 001c7237..da4eebf0 100644
--- a/spec/hamlit/engine/old_attributs_spec.rb
+++ b/spec/hamlit/engine/old_attributes_spec.rb
@@ -63,5 +63,14 @@ describe Hamlit::Engine do
         <body class='bb' data-confirm='really?' data-disable id='a'></body>
       HTML
     end
+
+    it 'renders runtime hash attribute' do
+      assert_render(<<-'HAML', <<-HTML)
+        - hash = { foo: 'bar' }
+        %span{ hash }
+      HAML
+        <span foo='bar'></span>
+      HTML
+    end
   end
 end