diff --git a/lib/mom/builtin.rb b/lib/mom/builtin.rb
index fb5e3d24..0c9852b6 100644
--- a/lib/mom/builtin.rb
+++ b/lib/mom/builtin.rb
@@ -34,7 +34,7 @@ module Mom
         if(space_type.methods.nil?)
           @compilers << compiler_for( space_type   , Space , :main)
         end
-        return @compilers 
+        return @compilers
       end
       # TODO go through the virtual parfait layer and adjust function names
       #      to what they really are
diff --git a/lib/parfait/behaviour.rb b/lib/parfait/behaviour.rb
index 183b4f0e..09340553 100644
--- a/lib/parfait/behaviour.rb
+++ b/lib/parfait/behaviour.rb
@@ -18,7 +18,7 @@ module Parfait
 
     def method_names
       names = List.new
-      self.methods.each do |method|
+      methods.each do |method|
         names.push method.name
       end
       names
@@ -31,13 +31,13 @@ module Parfait
 
     def remove_instance_method( method_name )
       found = get_instance_method( method_name )
-      found ? self.methods.delete(found) : false
+      found ? @methods.delete(found) : false
     end
 
     def get_instance_method( fname )
       raise "get_instance_method #{fname}.#{fname.class}" unless fname.is_a?(Symbol)
       #if we had a hash this would be easier.  Detect or find would help too
-      self.instance_methods.find {|m| m.name == fname }
+      @instance_methods.find {|m| m.name == fname }
     end
 
     # get the method and if not found, try superclasses. raise error if not found
@@ -46,7 +46,7 @@ module Parfait
       method = get_instance_method(m_name)
       return method if method
       if( super_class_name && super_class_name != :Object )
-        method = self.super_class.resolve_method(m_name)
+        method = @super_class.resolve_method(m_name)
       end
       method
     end
diff --git a/lib/parfait/binary_code.rb b/lib/parfait/binary_code.rb
index fae79e5a..3daa3766 100644
--- a/lib/parfait/binary_code.rb
+++ b/lib/parfait/binary_code.rb
@@ -7,7 +7,7 @@ module Parfait
   # and as the last code of each link is a jump to the next link.
   #
   class BinaryCode < Data32
-    attr :type, :next_code
+    attr_reader :type, :next_code
 
     def self.type_length
       2 #type + next (could get from space, maybe later)
@@ -27,11 +27,12 @@ module Parfait
 
     def initialize(total_size)
       super()
-      self.next_code = nil
+      @next_code = nil
       extend_to(total_size )
       (0 ... data_length).each{ |index| set_word(index , 0) }
       set_last(0)
     end
+
     def extend_to(total_size)
       return if total_size < data_length
       extend_one() unless next_code
@@ -39,7 +40,7 @@ module Parfait
     end
 
     def extend_one()
-      self.next_code = BinaryCode.new(1)
+      @next_code = BinaryCode.new(1)
       Risc::Position.get(self).trigger_inserted if Risc::Position.set?(self)
     end
 
@@ -107,9 +108,9 @@ module Parfait
       set_internal_word(word_index , char)
     end
     def total_byte_length(start = 0 )
-      start += self.byte_length
+      start += byte_length
       return start unless self.next_code
-      self.next_code.total_byte_length(start)
+      @next_code.total_byte_length(start)
     end
   end
 end
diff --git a/lib/parfait/cache_entry.rb b/lib/parfait/cache_entry.rb
index b68acc6d..5e9dee95 100644
--- a/lib/parfait/cache_entry.rb
+++ b/lib/parfait/cache_entry.rb
@@ -8,15 +8,15 @@
 module Parfait
   class CacheEntry < Object
 
-    attr :type, :cached_type, :cached_method
+    attr_reader :type, :cached_type, :cached_method
 
     def initialize(type , method)
-      self.cached_type = type
-      self.cached_method = method
+      @cached_type = type
+      @cached_method = method
     end
 
     def to_s
-      "CacheEntry" + "#{cached_method&.name}"
+      "CacheEntry" + "#{@cached_method&.name}"
     end
   end
 end
diff --git a/lib/parfait/callable.rb b/lib/parfait/callable.rb
index ea49f2e0..30ca51c5 100644
--- a/lib/parfait/callable.rb
+++ b/lib/parfait/callable.rb
@@ -12,9 +12,9 @@ module Parfait
   #
   class Callable < Object
 
-    attr :type, :self_type , :arguments_type , :frame_type , :binary
-    attr :blocks , :name
-    attr :next_callable
+    attr_reader :type, :self_type , :arguments_type , :frame_type , :binary
+    attr_reader :blocks , :name
+    attr_reader :next_callable
 
     def self.type_length
       8
@@ -25,8 +25,8 @@ module Parfait
       raise "No class #{self}" unless self_type
       raise "For type, not class #{self_type}" unless self_type.is_a?(Type)
       raise "Mixup" unless name.is_a?(Symbol)
-      self.name = name
-      self.self_type = self_type
+      @name = name
+      @self_type = self_type
       init(arguments_type, frame_type)
     end
 
@@ -38,9 +38,9 @@ module Parfait
     def init(arguments_type, frame_type)
       raise "Wrong argument type, expect Type not #{arguments_type.class}" unless arguments_type.is_a? Type
       raise "Wrong frame type, expect Type not #{frame_type.class}" unless frame_type.is_a? Type
-      self.arguments_type = arguments_type
-      self.frame_type = frame_type
-      self.binary = BinaryCode.new(0)
+      @arguments_type = arguments_type
+      @frame_type = frame_type
+      @binary = BinaryCode.new(0)
     end
 
     # determine if method has a local variable or tmp (anonymous local) by given name
@@ -52,7 +52,7 @@ module Parfait
     def add_local( name , type )
       index = has_local( name )
       return index if index
-      self.frame_type = frame_type.add_instance_variable(name,type)
+      @frame_type = frame_type.add_instance_variable(name,type)
     end
 
     def each_binary( &block )
@@ -64,7 +64,7 @@ module Parfait
     end
 
     def set_next( method )
-      self.next_callable = method
+      @next_callable = method
     end
 
   end
diff --git a/lib/parfait/callable_method.rb b/lib/parfait/callable_method.rb
index 5d76d1bd..4fc01faa 100644
--- a/lib/parfait/callable_method.rb
+++ b/lib/parfait/callable_method.rb
@@ -14,16 +14,16 @@ module Parfait
 
     def ==(other)
       return false unless other.is_a?(CallableMethod)
-      return false if name != other.name
+      return false if @name != other.name
       super
     end
 
     def rxf_reference_name
-      "Method: " + name.to_s
+      "Method: " + @name.to_s
     end
 
     def inspect
-      "#{self_type.object_class.name}:#{name}(#{arguments_type.inspect})"
+      "#{@self_type.object_class.name}:#{@name}(#{@arguments_type.inspect})"
     end
 
     def each_method( &block )
@@ -32,14 +32,14 @@ module Parfait
     end
 
     def create_block(args , frame)
-      block_name = "#{name}_block".to_sym #TODO with id, to distinguish
-      add_block( Block.new(block_name , self_type , args , frame))
+      block_name = "#{@name}_block".to_sym #TODO with id, to distinguish
+      add_block( Block.new(block_name , @self_type , args , frame))
     end
 
     def add_block(bl)
       was = blocks
       bl.set_next(was) if(was)
-      self.blocks = bl
+      @blocks = bl
     end
 
     def has_block(block)
@@ -47,7 +47,7 @@ module Parfait
       false
     end
     def each_block(&bl)
-      blo = blocks
+      blo = @blocks
       while( blo )
         yield(blo)
         blo = blo.next_callable
diff --git a/lib/parfait/class.rb b/lib/parfait/class.rb
index 45e8da89..d4bf6e1d 100644
--- a/lib/parfait/class.rb
+++ b/lib/parfait/class.rb
@@ -18,8 +18,8 @@ module Parfait
   class Class < Object
     include Behaviour
 
-    attr :type, :instance_type , :name , :instance_methods
-    attr :super_class_name , :meta_class
+    attr_reader :type, :instance_type , :name , :instance_methods
+    attr_reader :super_class_name , :meta_class
 
     def self.type_length
       6
@@ -27,11 +27,11 @@ module Parfait
 
     def initialize( name , superclass , instance_type)
       super()
-      self.name = name
-      self.super_class_name = superclass
-      self.instance_methods = List.new
+      @name = name
+      @super_class_name = superclass
+      @instance_methods = List.new
       set_instance_type( instance_type )
-      self.meta_class = MetaClass.new( self )
+      @meta_class = MetaClass.new( self )
     end
 
     def rxf_reference_name
@@ -59,14 +59,14 @@ module Parfait
 
     # adding an instance changes the instance_type to include that variable
     def add_instance_variable( name , type)
-      self.instance_type = instance_type.add_instance_variable( name , type )
+      @instance_type = instance_type.add_instance_variable( name , type )
     end
 
     # setting the type generates all methods for this type
     # (or will do, once we store the methods code to do that)
     def set_instance_type( type )
       raise "type must be type #{type}" unless type.is_a?(Type)
-      self.instance_type = type
+      @instance_type = type
     end
 
     # return the super class, but raise exception if either the super class name
diff --git a/lib/parfait/dictionary.rb b/lib/parfait/dictionary.rb
index 4c874e7f..79d65b28 100644
--- a/lib/parfait/dictionary.rb
+++ b/lib/parfait/dictionary.rb
@@ -3,7 +3,7 @@
 module Parfait
   class Dictionary < Object
 
-    attr :type, :i_keys , :i_values
+    attr_reader :type, :i_keys , :i_values
 
     def self.type_length
       3
@@ -14,30 +14,30 @@ module Parfait
     # internally we store keys and values in lists, which means this does **not** scale well
     def initialize
       super()
-      self.i_keys = List.new()
-      self.i_values = List.new()
+      @i_keys = List.new()
+      @i_values = List.new()
     end
 
     def keys
-      i_keys.dup
+      @i_keys.dup
     end
 
     def values
-      i_values.dup
+      @i_values.dup
     end
 
     # are there any key/value items in the list
     def empty?
-      i_keys.empty?
+      @i_keys.empty?
     end
 
     # How many key/value pairs there are
     def length()
-      return i_keys.get_length()
+      return @i_keys.get_length()
     end
 
     def next_value(val)
-      return i_values.next_value(val)
+      return @i_values.next_value(val)
     end
 
     # get a value fot the given key
@@ -46,7 +46,7 @@ module Parfait
     def get(key)
       index = key_index(key)
       if( index )
-        i_values.get(index)
+        @i_values.get(index)
       else
         nil
       end
@@ -59,17 +59,17 @@ module Parfait
 
     # private method
     def key_index(key)
-      i_keys.index_of(key)
+      @i_keys.index_of(key)
     end
 
     # set key with value, returns value
     def set(key , value)
       index = key_index(key)
       if( index )
-        i_values.set(index , value)
+        @i_values.set(index , value)
       else
-        i_keys.push(key)
-        i_values.push(value)
+        @i_keys.push(key)
+        @i_values.push(value)
       end
       value
     end
@@ -82,9 +82,9 @@ module Parfait
     # yield to each key value pair
     def each
       index = 0
-      while index < i_keys.get_length
-        key = i_keys.get(index)
-        value = i_values.get(index)
+      while index < @i_keys.get_length
+        key = @i_keys.get(index)
+        value = @i_values.get(index)
         yield key , value
         index = index + 1
       end
diff --git a/lib/parfait/factory.rb b/lib/parfait/factory.rb
index 86c3b417..08ccd6d5 100644
--- a/lib/parfait/factory.rb
+++ b/lib/parfait/factory.rb
@@ -14,15 +14,15 @@
 
 module Parfait
   class Factory < Object
-    attr :type , :for_type , :next_object , :reserve , :attribute_name , :page_size
+    attr_reader :type , :for_type , :next_object , :reserve , :attribute_name , :page_size
 
     # initialize for a given type (for_type). The attribute that is used to create the
     # list is the first that starts with next_ . "next" itself would have been nice and general
     # but is a keyword, so no go.
     def initialize(type , page)
-      self.for_type = type
-      self.attribute_name = type.names.find {|name| name.to_s.start_with?("next")}
-      self.page_size = page
+      @for_type = type
+      @attribute_name = type.names.find {|name| name.to_s.start_with?("next")}
+      @page_size = page
       raise "No next found for #{type.class_name}" unless attribute_name
     end
 
@@ -32,7 +32,7 @@ module Parfait
     # used, as it get's called from risc (or will)
     def get_next_object
       unless( next_object )
-        self.next_object = reserve
+        @next_object = reserve
         get_more
       end
       get_head
@@ -41,7 +41,7 @@ module Parfait
     # this gets the head of the freelist, swaps it out agains the next and returns it
     def get_head
       nekst = next_object
-      self.next_object = get_next_for(nekst)
+      @next_object = get_next_for(nekst)
       return nekst
     end
 
@@ -49,15 +49,15 @@ module Parfait
     # and rebuilt the reserve (get_next already instantiates the reserve)
     #
     def get_more
-      self.reserve = get_chain
-      last_link = self.reserve
-      count = self.page_size / 100
+      @reserve = get_chain
+      last_link = @reserve
+      count = @page_size / 100
       count = 15 if count < 15
       while(count > 0)
         last_link = get_next_for(last_link)
         count -= 1
       end
-      self.next_object = get_next_for(last_link)
+      @next_object = get_next_for(last_link)
       set_next_for( last_link , nil )
       self
     end
@@ -65,10 +65,10 @@ module Parfait
     # this initiates the syscall to get more memory.
     # it creates objects from the mem and link them into a chain
     def get_chain
-      raise "type is nil" unless self.for_type
-      first = sys_mem( for_type , self.page_size)
+      raise "type is nil" unless @for_type
+      first = sys_mem( for_type , @page_size)
       chain = first
-      counter = self.page_size
+      counter = @page_size
       while( counter > 0)
         nekst = get_next_raw( chain )
         set_next_for(chain,  nekst)
@@ -87,7 +87,7 @@ module Parfait
     # set the next_* attribute of the given object, with the value.
     # the attribute name is determined in initialize
     def set_next_for(object , value)
-      object.send("#{attribute_name}=".to_sym , value)
+      object.send("_set_#{attribute_name}".to_sym , value)
     end
 
     # Return the object _after the given one. In memory terms the next object starts
diff --git a/lib/parfait/integer.rb b/lib/parfait/integer.rb
index 550abf45..3484f043 100644
--- a/lib/parfait/integer.rb
+++ b/lib/parfait/integer.rb
@@ -6,11 +6,11 @@
 module Parfait
   class Integer < Data4
 
-    attr :type, :next_integer
+    attr_reader :type, :next_integer
 
     def initialize(value , next_i = nil)
       super()
-      self.next_integer = next_i
+      @next_integer = next_i
       set_internal_word(Integer.integer_index, value)
     end
 
@@ -39,6 +39,9 @@ module Parfait
       set_internal_word(Integer.integer_index, value)
     end
 
+    def _set_next_integer(nekst)
+      @next_integer = nekst
+    end
     # :integer?, :odd?, :even?, :upto, :downto, :times, :succ, :next, :pred, :chr, :ord, :to_i, :to_int, :floor,
     # :ceil, :truncate, :round, :gcd, :lcm, :gcdlcm, :numerator, :denominator, :to_r, :rationalize,
     # :singleton_method_added, :coerce, :i, :+, :-, :fdiv, :div, :divmod, :%, :modulo, :remainder, :abs, :magnitude,
diff --git a/lib/parfait/list.rb b/lib/parfait/list.rb
index 686bc4e2..28e03d88 100644
--- a/lib/parfait/list.rb
+++ b/lib/parfait/list.rb
@@ -7,7 +7,7 @@
 
 module Parfait
   class List < Data16
-    attr :type, :indexed_length , :next_list
+    attr_reader :type, :indexed_length , :next_list
 
     def self.type_length
       3    # 0 type , 1 length , 2 - next_list
@@ -18,20 +18,20 @@ module Parfait
 
     def initialize
       super
-      self.indexed_length = 0
+      @indexed_length = 0
     end
 
     def data_length
       self.class.data_length
     end
     def get_length
-      r = indexed_length
+      r = @indexed_length
       r.nil? ? 0 : r
     end
 
     def ensure_next
-      self.next_list = List.new unless next_list
-      self.next_list
+      @next_list = List.new unless @next_list
+      @next_list
     end
 
     # set the value at index.
@@ -43,7 +43,7 @@ module Parfait
       end
       if index >= data_length
         ensure_next
-        next_list.set( index - data_length , value)
+        @next_list.set( index - data_length , value)
       else
         set_internal_word( index + self.class.type_length, value)
       end
@@ -54,8 +54,8 @@ module Parfait
     def get( index )
       raise "Only positive indexes, #{index}" if index < 0
       if index >= data_length
-        return nil unless next_list
-        return next_list.get( index - data_length)
+        return nil unless @next_list
+        return @next_list.get( index - data_length)
       else
         ret = nil
         if(index < get_length)
@@ -273,7 +273,7 @@ module Parfait
     end
     private
     def internal_set_length( i )
-      self.indexed_length = i
+      @indexed_length = i
     end
   end
 
diff --git a/lib/parfait/message.rb b/lib/parfait/message.rb
index 42f96975..9620c6db 100644
--- a/lib/parfait/message.rb
+++ b/lib/parfait/message.rb
@@ -15,15 +15,15 @@ module Parfait
     # :return_address => :Integer, :return_value => :Integer,
     # :caller => :Message , :name => :Word , :arguments => :NamedList
 
-    attr  :type, :next_message
-    attr  :receiver
-    attr  :return_address, :return_value
-    attr  :caller , :method
-    attr  :arguments_given
-    attr  :arg1 , :arg2, :arg3, :arg4, :arg5, :arg6
-    attr  :locals_used
-    attr  :local1 , :local2, :local3, :local4, :local5, :local6 ,:local7,:local8
-    attr  :local9 ,:local10, :local11 , :local12, :local13, :local14
+    attr_reader  :type, :next_message
+    attr_reader  :receiver
+    attr_reader  :return_address, :return_value
+    attr_reader  :caller , :method
+    attr_reader  :arguments_given
+    attr_reader  :arg1 , :arg2, :arg3, :arg4, :arg5, :arg6
+    attr_reader  :locals_used
+    attr_reader  :local1 , :local2, :local3, :local4, :local5, :local6 ,:local7,:local8
+    attr_reader  :local9 ,:local10, :local11 , :local12, :local13, :local14
 
     def self.type_length
       31
@@ -40,25 +40,38 @@ module Parfait
 
     def initialize(  )
       super()
-      self.locals_used = Parfait::Integer.new(0)
-      self.arguments_given = Parfait::Integer.new(0)
+      @locals_used = Parfait::Integer.new(0)
+      @arguments_given = Parfait::Integer.new(0)
     end
     public :initialize
 
     def set_receiver(rec)
-      self.receiver = rec
+      @receiver = rec
     end
 
     def set_caller(caller)
-      caller = caller
+      @caller = caller
     end
 
     def get_type_for(name)
-      index = type.get_index(name)
+      index = @type.get_index(name)
       get_at(index)
     end
+
+    def method_name
+      return "" unless @method
+      return "" unless @method == NilClass
+      @method.name
+    end
     def to_s
-      "Message:#{method&.name}(#{arguments_given})"
+      "Message:#{method_name}(#{@arguments_given})"
+    end
+
+    def _set_next_message(nekst)
+      @next_message = nekst
+    end
+    def _set_caller(prev)
+      @caller = prev
     end
   end
 end
diff --git a/lib/parfait/meta_class.rb b/lib/parfait/meta_class.rb
index f3f25de4..34eb0f7c 100644
--- a/lib/parfait/meta_class.rb
+++ b/lib/parfait/meta_class.rb
@@ -20,7 +20,7 @@ module Parfait
   class MetaClass < Object
     include Behaviour
 
-    attr :type, :instance_type , :instance_methods , :clazz
+    attr_reader :type, :instance_type , :instance_methods , :clazz
 
     def self.type_length
       4
@@ -28,17 +28,17 @@ module Parfait
 
     def initialize( clazz )
       super()
-      self.clazz = clazz
-      self.instance_methods = List.new
+      @clazz = clazz
+      @instance_methods = List.new
       set_instance_type( clazz.get_type() )
     end
 
     def rxf_reference_name
-      clazz.name
+      @clazz.name
     end
 
     def inspect
-      "MetaClass(#{clazz.name})"
+      "MetaClass(#{@clazz.name})"
     end
 
     def add_method_for(name , type , frame , body )
@@ -49,23 +49,23 @@ module Parfait
 
     def add_method(method)
       raise "Must be untyped method #{method}" unless method.is_a? Parfait::VoolMethod
-      instance_methods.push(method)
+      @instance_methods.push(method)
     end
 
     def get_method(name)
-      instance_methods.find{|m| m.name == name }
+      @instance_methods.find{|m| m.name == name }
     end
 
     # adding an instance changes the instance_type to include that variable
     def add_instance_variable( name , type)
-      self.instance_type = instance_type.add_instance_variable( name , type )
+      @instance_type = @instance_type.add_instance_variable( name , type )
     end
 
     # setting the type generates all methods for this type
     # (or will do, once we store the methods code to do that)
     def set_instance_type( type )
-      raise "type must be type #{type}" unless type.is_a?(Type)
-      self.instance_type = type
+      raise "type must be type #{type.class}:#{type}" unless type.is_a?(Type)
+      @instance_type = type
     end
 
     # Nil name means no superclass, and so nil returned
diff --git a/lib/parfait/named_list.rb b/lib/parfait/named_list.rb
index f08e2ffb..5745d236 100644
--- a/lib/parfait/named_list.rb
+++ b/lib/parfait/named_list.rb
@@ -23,7 +23,7 @@
 module Parfait
   class NamedList < Object
 
-    attr :type
+    attr_reader :type
 
     def self.memory_size
       16
diff --git a/lib/parfait/object.rb b/lib/parfait/object.rb
index 2865c15a..b4e14f60 100644
--- a/lib/parfait/object.rb
+++ b/lib/parfait/object.rb
@@ -14,7 +14,10 @@
 
 module Parfait
   class Object
-    attr :type
+    attr_reader :type
+    def type=(t)
+      set_type( t )
+    end
 
     def == other
       self.object_id == other.object_id
@@ -34,38 +37,39 @@ module Parfait
     # private
     def set_type(typ)
       raise "not type" + typ.class.to_s + "in " + object_id.to_s(16) unless typ.is_a?(Type)
-      self.type = typ
+      @type = typ
     end
 
     # so we can keep the raise in get_type
     def has_type?
-      ! type.nil?
+      ! @type.nil?
     end
 
     def get_type()
       raise "No type " + self.object_id.to_s(16) + ":" + self.class.name unless has_type?
-      type
+      @type
     end
 
     def get_instance_variables
-      type.names
+      @type.names
     end
 
     def get_instance_variable( name )
       index = instance_variable_defined(name)
-      #puts "getting #{name} at #{index}"
+      #raise "at :#{name}:" if name.to_s[0] == "@"
       return nil if index == nil
       return get_internal_word(index)
     end
 
     def set_instance_variable( name , value )
       index = instance_variable_defined(name)
+      #puts "setting #{name} at #{index}"
       return nil if index == nil
       return set_internal_word(index , value)
     end
 
     def instance_variable_defined( name )
-      type.variable_index(name)
+      @type.variable_index(name)
     end
 
     # objects only come in lengths of multiple of 8 words / 32 bytes
@@ -81,7 +85,7 @@ module Parfait
     end
 
     def padded_length
-      Object.padded_words( type.instance_length )
+      Object.padded_words( @type.instance_length )
     end
 
     # parfait versions are deliberately called different, so we "relay"
diff --git a/lib/parfait/space.rb b/lib/parfait/space.rb
index c7efedc1..248ba9a8 100644
--- a/lib/parfait/space.rb
+++ b/lib/parfait/space.rb
@@ -30,16 +30,16 @@ module Parfait
 
   class Space < Object
 
-    attr  :type, :classes , :types , :factories
-    attr  :true_object , :false_object , :nil_object
+    attr_reader  :type, :classes , :types , :factories
+    attr_reader  :true_object , :false_object , :nil_object
 
     def initialize( classes , pages)
-      self.classes = classes
-      self.types = Dictionary.new
+      @classes = classes
+      @types = Dictionary.new
       classes.each do |name , cl|
         add_type(cl.instance_type)
       end
-      self.factories = Dictionary.new
+      @factories = Dictionary.new
       [:Integer , :ReturnAddress , :Message].each do |fact_name|
         for_type = classes[fact_name].instance_type
         page_size = pages[fact_name] || 1024
@@ -49,9 +49,9 @@ module Parfait
       end
       init_message_chain( factories[ :Message ].reserve  )
       init_message_chain( factories[ :Message ].next_object  )
-      self.true_object = Parfait::TrueClass.new
-      self.false_object = Parfait::FalseClass.new
-      self.nil_object = Parfait::NilClass.new
+      @true_object = Parfait::TrueClass.new
+      @false_object = Parfait::FalseClass.new
+      @nil_object = Parfait::NilClass.new
     end
 
     def self.type_length
@@ -65,7 +65,7 @@ module Parfait
       prev = nil
       while(message)
         message.initialize
-        message.caller = prev if prev
+        message._set_caller(prev) if prev
         prev = message
         message = message.next_message
       end
@@ -73,18 +73,18 @@ module Parfait
     # return the factory for the given type
     # or more exactly the type that has a class_name "name"
     def get_factory_for(name)
-      factories[name]
+      @factories[name]
     end
 
     # use the factory of given name to generate next_object
     # just a shortcut basically
     def get_next_for(name)
-      factories[name].get_next_object
+      @factories[name].get_next_object
     end
 
     # yield each type in the space
     def each_type
-      types.values.each do |type|
+      @types.values.each do |type|
         yield(type)
       end
     end
@@ -100,7 +100,7 @@ module Parfait
 
     # get a type by the type hash (the hash is what uniquely identifies the type)
     def get_type_for( hash )
-      types[hash]
+      @types[hash]
     end
 
     # all methods form all types
@@ -137,7 +137,7 @@ module Parfait
     # return nili if no such class. Use bang version if create should be implicit
     def get_class_by_name( name )
       raise "get_class_by_name #{name}.#{name.class}" unless name.is_a?(Symbol)
-      c = classes[name]
+      c = @classes[name]
       #puts "MISS, no class #{name} #{name.class}" unless c # " #{classes}"
       #puts "CLAZZ, #{name} #{c.get_type.get_length}" if c
       c
@@ -159,7 +159,7 @@ module Parfait
       raise "create_class #{superclass.class}" unless superclass.is_a? Symbol
       type = get_type_by_class_name(superclass)
       c = Class.new(name , superclass , type )
-      classes[name] = c
+      @classes[name] = c
     end
 
     def rxf_reference_name
diff --git a/lib/parfait/type.rb b/lib/parfait/type.rb
index 7f190a25..82290734 100644
--- a/lib/parfait/type.rb
+++ b/lib/parfait/type.rb
@@ -36,7 +36,7 @@ module Parfait
 
   class Type < Object
 
-    attr :type, :object_class , :names , :types , :methods
+    attr_reader :type, :object_class , :names , :types , :methods
 
     def self.type_length
       5
@@ -57,18 +57,18 @@ module Parfait
     # this part of the init is seperate because at boot time we can not use normal new
     # new is overloaded to grab the type from space, and before boot, that is not set up
     def init_lists(hash)
-      self.methods = nil
-      self.names = List.new
-      self.types = List.new
+      @methods = nil
+      @names = List.new
+      @types = List.new
       raise "No type Type in #{hash}" unless hash[:type]
       private_add_instance_variable(:type , hash[:type]) #first
-      hash.each do |name , type|
-        private_add_instance_variable(name , type) unless name == :type
+      hash.keys.each do |name |
+        private_add_instance_variable(name , hash[name]) unless name == :type
       end
     end
 
     def class_name
-      object_class.name
+      @object_class.name
     end
 
     def to_s
@@ -87,7 +87,7 @@ module Parfait
 
     def method_names
       names = List.new
-      return names unless methods
+      return names unless @methods
       methods.each_method do |method|
         names.push method.name
       end
@@ -119,7 +119,7 @@ module Parfait
         remove_method(method.name)
       end
       method.set_next( methods )
-      self.methods = method
+      @methods = method
       #puts "#{self.name} add #{method.name}"
       method
     end
@@ -127,7 +127,7 @@ module Parfait
     def remove_method( method_name )
       raise "No such method #{method_name} in #{self.name}" unless methods
       if( methods.name == method_name)
-        self.methods = methods.next_callable
+        @methods = methods.next_callable
         return true
       end
       method = methods
@@ -190,7 +190,7 @@ module Parfait
 
     def set_object_class(oc)
       raise "object class should be a class, not #{oc.class}" unless oc.is_a?(Class)
-      self.object_class = oc
+      @object_class = oc
     end
 
     def instance_length
diff --git a/lib/parfait/vool_method.rb b/lib/parfait/vool_method.rb
index 59023d30..a24aac96 100644
--- a/lib/parfait/vool_method.rb
+++ b/lib/parfait/vool_method.rb
@@ -12,13 +12,13 @@ module Parfait
   #
   class VoolMethod < Object
 
-    attr :type, :name , :args_type , :frame_type
+    attr_reader :type, :name , :args_type , :frame_type
     attr_reader :source
 
     def initialize(name , args_type , frame_type , source )
-      self.name = name
-      self.args_type = args_type
-      self.frame_type = frame_type
+      @name = name
+      @args_type = args_type
+      @frame_type = frame_type
       @source = source
       raise "Name must be symbol" unless name.is_a?(Symbol)
       raise "args_type must be type" unless args_type.is_a?(Parfait::Type)
@@ -29,7 +29,7 @@ module Parfait
 
     def create_callable_method( type )
       raise "create_method #{type.inspect} is not a Type" unless type.is_a? Parfait::Type
-      type.create_method( name , args_type , frame_type)
+      type.create_method( @name , @args_type , @frame_type)
     end
 
     def compiler_for(self_type)
diff --git a/lib/parfait/word.rb b/lib/parfait/word.rb
index ab1fa51f..75013009 100644
--- a/lib/parfait/word.rb
+++ b/lib/parfait/word.rb
@@ -13,7 +13,7 @@ module Parfait
   # Object length is measured in non-type cells though
 
   class Word < Data8
-    attr :type, :char_length
+    attr_reader :type, :char_length
 
     def self.type_length
       2    # 0 type , 1 char_length
@@ -26,7 +26,7 @@ module Parfait
     # Risc provides methods to create Parfait objects from ruby
     def initialize( len )
       super()
-      self.char_length = 0
+      @char_length = 0
       raise "Must init with int, not #{len.class}" unless len.kind_of? ::Integer
       raise "Must init with positive, not #{len}" if len < 0
       fill_to( len , 32 ) unless len == 0 #32 being ascii space
@@ -36,10 +36,10 @@ module Parfait
 
     # return a copy of self
     def copy
-      cop = Word.new( self.length )
+      cop = Word.new( @char_length )
       index = 0
-      while( index < self.length )
-        cop.set_char(index , self.get_char(index))
+      while( index < @char_length )
+        cop.set_char(index , get_char(index))
         index = index + 1
       end
       cop
@@ -47,8 +47,7 @@ module Parfait
 
     # return the number of characters
     def length()
-      obj_len = char_length
-      return obj_len
+      @char_length
     end
 
     # make every char equal the given one
@@ -57,7 +56,7 @@ module Parfait
     end
 
     def fill_from_with( from , char )
-      len = self.length()
+      len = @char_length
       return if from < 0
       while( from < len)
         set_char( from , char)
@@ -68,16 +67,16 @@ module Parfait
 
     # true if no characters
     def empty?
-      return self.length == 0
+      return @char_length == 0
     end
 
     # pad the string with the given character to the given length
     #
     def fill_to(len , fill_char)
       return if len <= 0
-      old = char_length
+      old = @char_length
       return if old >= len
-      self.char_length = len
+      @char_length = len
       check_length
       fill_from_with( old  , fill_char )
     end
@@ -170,7 +169,7 @@ module Parfait
       string = ""
       index = 0
       #puts "Length = #{char_length}"
-      while( index < char_length)
+      while( index < @char_length)
         char = get_char(index)
         string += char ? char.chr : "*"
         index = index + 1
@@ -184,12 +183,12 @@ module Parfait
     end
 
     def padded_length
-      Object.padded( 4 * get_type().instance_length + char_length  )
+      Object.padded( 4 * get_type().instance_length + @char_length  )
     end
 
     private
     def check_length
-      raise "Length out of bounds #{char_length}" if char_length > 1000
+      raise "Length out of bounds #{char_length}" if @char_length > 1000
     end
   end
 
diff --git a/lib/risc/parfait_adapter.rb b/lib/risc/parfait_adapter.rb
index c1434752..660efa84 100644
--- a/lib/risc/parfait_adapter.rb
+++ b/lib/risc/parfait_adapter.rb
@@ -1,31 +1,43 @@
 require_relative "fake_memory"
 
-module Parfait
-  class Object
 
+module Parfait
+  class Object ; end
+  class DataObject < Object
     def self.allocate
       r = super
       r.instance_variable_set(:@memory , Risc::FakeMemory.new(r ,self.type_length , self.memory_size))
       r
     end
-
     # 0 -based index
     def get_internal_word(index)
-      @memory[index]
+      super(index) if index < self.class.type_length
+      @memory[ index ]
     end
 
     # 0 -based index
     def set_internal_word(index , value)
-      @memory[index] = value
-      value
+      return super(index,value) if index < self.class.type_length
+      @memory[ index ] = value
+    end
+  end
+
+  class Object
+
+    # 0 -based index
+    def get_internal_word(index)
+      return @type if index == Parfait::TYPE_INDEX
+      name = Parfait.name_for_index(self , index)
+      return nil unless name
+      instance_eval("@#{name}")
     end
 
-    def self.attr( *attributes )
-      attributes = [attributes] unless attributes.is_a?(Array)
-      attributes.each do |name|
-        define_getter(name)
-        define_setter(name)
-      end
+    # 0 -based index
+    def set_internal_word(index , value)
+      name = Parfait.name_for_index(self , index)
+      raise "no string #{name.class}" unless name.is_a?(Symbol)
+      instance_eval("@#{name}=value" )
+      value
     end
 
     def self.variable_index( name)
@@ -39,22 +51,6 @@ module Parfait
       i + 1
     end
 
-    def self.define_getter(name)
-      index = variable_index(name)
-      define_method(name) do
-        #puts "GETTING #{name} for #{self.class.name} in #{object_id.to_s(16)}"
-        @memory._get(index)
-      end
-    end
-
-    def self.define_setter(name)
-      index = variable_index(name)
-      define_method("#{name}=".to_sym ) do |value|
-        #puts "SETTING #{name}= for #{self.class.name} in #{object_id.to_s(16)}"
-        @memory._set(index , value)
-      end
-    end
-
     def self.cattr( *names )
       names.each do |ca|
         class_eval "@@#{ca} = 0"
diff --git a/lib/risc/parfait_boot.rb b/lib/risc/parfait_boot.rb
index e07b8eda..465721c8 100644
--- a/lib/risc/parfait_boot.rb
+++ b/lib/risc/parfait_boot.rb
@@ -181,4 +181,13 @@ module Parfait
       Word: {char_length: :Integer , next_word: :Word} ,
       }
   end
+  def self.name_for_index(object , index)
+    return :type if index == 0
+    clazz = object.class.name.split("::").last.to_sym
+    cl = self.type_names[clazz]
+    keys = cl.keys
+    keys[index - 1] # -1 because type is excluded in the lists (FIX)
+    # FIXME Now that we use instance variables in parfait, they should be parsed
+    # and the type_names generated automatically
+  end
 end