diff --git a/lib/mom/mom_compiler.rb b/lib/mom/mom_compiler.rb
index 17160ad7..68cec826 100644
--- a/lib/mom/mom_compiler.rb
+++ b/lib/mom/mom_compiler.rb
@@ -3,12 +3,7 @@ module Mom
     attr_reader :method_compilers
 
     def initialize(compilers = [])
-      @method_compilers = compilers
-      Risc::Builtin.boot_functions.each do |boot_comp|
-        next if @method_compilers.find{|comp| comp.method == boot_comp.method }        
-        @method_compilers << boot_comp
-      end
-
+      @method_compilers = compilers + Risc::Builtin.boot_functions
     end
 
     # collects constants from all compilers into one array
diff --git a/lib/risc/builtin.rb b/lib/risc/builtin.rb
index 85508fef..c933544b 100644
--- a/lib/risc/builtin.rb
+++ b/lib/risc/builtin.rb
@@ -12,15 +12,17 @@ module Risc
     # This should return the implementation of the method (ie a method object),
     # not actually try to implement it(as that's impossible in ruby)
     #
-    def self.boot_functions
-      compilers = []
-      space = Parfait.object_space
-      # very fiddly chicken 'n egg problem. Functions need to be in the right order,
-      # and in fact we  have to define some dummies, just for the others to compile
+    # When no main has been compiled, we will add an empty main (for testing)
+    #
+    def self.boot_functions(add_main = false)
       # TODO go through the virtual parfait layer and adjust function names
       #      to what they really are
+      compilers = []
+      space = Parfait.object_space
       space_type = space.get_class.instance_type
-      compilers << compiler_for( space_type   , Space , :main)
+      if(space_type.methods.nil?)
+        compilers << compiler_for( space_type   , Space , :main)
+      end
 
       obj_type = space.get_class_by_name(:Object).instance_type
       [ :get_internal_word , :set_internal_word , :_method_missing,
diff --git a/test/mom/test_mom_compiler.rb b/test/mom/test_mom_compiler.rb
index c1285312..0005226c 100644
--- a/test/mom/test_mom_compiler.rb
+++ b/test/mom/test_mom_compiler.rb
@@ -13,10 +13,10 @@ module Mom
       assert_equal MomCompiler , @comp.class
     end
     def test_compilers
-      assert_equal 24 , @comp.method_compilers.length
+      assert_equal 23 , @comp.method_compilers.length
     end
     def test_compilers_bare
-      assert_equal 23 , MomCompiler.new.method_compilers.length
+      assert_equal 22 , MomCompiler.new.method_compilers.length
     end
     def test_returns_constants
       assert_equal Array , @comp.constants.class