diff --git a/test/test_dyn_optiondescription.py b/test/test_dyn_optiondescription.py
index 03ba3fa..62889fb 100644
--- a/test/test_dyn_optiondescription.py
+++ b/test/test_dyn_optiondescription.py
@@ -118,8 +118,8 @@ def test_getdoc_dyndescription():
     assert api.option('od.dodval2').option.name() == 'dodval2'
     assert api.option('od.dodval1.stval1').option.doc() == 'doc1'
     assert api.option('od.dodval2.stval2').option.doc() == 'doc1'
-    assert api.option('od.dodval1').option.doc() == 'doc2'
-    assert api.option('od.dodval2').option.doc() == 'doc2'
+    assert api.option('od.dodval1').option.doc() == 'doc2val1'
+    assert api.option('od.dodval2').option.doc() == 'doc2val2'
 
 
 def test_mod_dyndescription():
@@ -542,6 +542,35 @@ def test_requires_dyndescription():
     assert frozenset(props) == frozenset(['disabled'])
 
 
+def test_requires_dyndescription_in_dyn():
+    boolean = BoolOption('boolean', '', True)
+    st = StrOption('st', '', requires=[{'option': boolean, 'expected': False,
+                                        'action': 'disabled'}])
+    dod = DynOptionDescription('dod', '', [boolean, st], callback=return_list)
+    od = OptionDescription('od', '', [dod])
+    od2 = OptionDescription('od', '', [od])
+    cfg = Config(od2)
+    cfg.property.read_write()
+
+    assert cfg.option('od.dodval1.stval1').value.get() is None
+    assert cfg.option('od.dodval2.stval2').value.get() is None
+    #
+    cfg.option('od.dodval1.booleanval1').value.set(False)
+
+    props = []
+    try:
+        cfg.option('od.dodval1.stval1').value.get()
+    except PropertiesOptionError as err:
+        props = err.proptype
+    assert props == frozenset(['disabled'])
+    props = []
+    cfg.option('od.dodval2.stval2').value.get()
+    #
+    cfg.option('od.dodval1.booleanval1').value.set(True)
+    assert cfg.option('od.dodval1.stval1').value.get() is None
+    assert cfg.option('od.dodval2.stval2').value.get() is None
+
+
 def test_requires_dyndescription2():
     boolean = BoolOption('boolean', '', True)
     st1 = StrOption('st', '')
@@ -920,6 +949,219 @@ def test_masterslaves_dyndescription():
     assert api.option('od.stval2.st1val2.st1val2').owner.isdefault()
 
 
+def test_masterslaves_default_multi_dyndescription():
+    st1 = StrOption('st1', "", multi=True)
+    st2 = StrOption('st2', "", multi=True, default_multi='no')
+    stm = MasterSlaves('st1', '', [st1, st2])
+    st = DynOptionDescription('st', '', [stm], callback=return_list)
+    od = OptionDescription('od', '', [st])
+    od2 = OptionDescription('od', '', [od])
+    api = Config(od2)
+    owner = api.owner.get()
+    #
+    assert api.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert api.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert api.option('od.stval1.st1val1.st1val1').owner.isdefault()
+    assert api.option('od.stval2.st1val2.st1val2').owner.isdefault()
+    #
+    api.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    assert api.option('od.stval1.st1val1.st1val1').value.get() == ['yes']
+    assert api.option('od.stval1.st1val1.st2val1', 0).value.get() == 'no'
+    assert api.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert api.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert api.option('od.stval1.st1val1.st2val1', 0).owner.isdefault()
+    assert api.option('od.stval2.st1val2.st1val2').owner.isdefault()
+
+def test_masterslaves_dyndescription_param():
+    val1 = StrOption('val1', '', ['val1', 'val2'], multi=True)
+    odval = OptionDescription('odval1', '', [val1])
+    st1 = StrOption('st1', "", multi=True)
+    st2 = StrOption('st2', "", multi=True)
+    stm = MasterSlaves('st1', '', [st1, st2])
+    st = DynOptionDescription('st', '', [stm], callback=return_list, callback_params=Params(ParamOption(val1)))
+    od = OptionDescription('od', '', [st, odval])
+    od2 = OptionDescription('od', '', [od])
+    cfg = Config(od2)
+    owner = cfg.owner.get()
+    assert cfg.option.make_dict() == {'od.stval1.st1val1.st2val1': [], 'od.stval2.st1val2.st2val2': [], 'od.stval2.st1val2.st1val2': [], 'od.stval1.st1val1.st1val1': [], 'od.odval1.val1': ['val1', 'val2']}
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owners.default
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    assert cfg.option.make_dict() == {'od.stval1.st1val1.st2val1': [None], 'od.stval2.st1val2.st2val2': [], 'od.stval2.st1val2.st1val2': [], 'od.stval1.st1val1.st1val1': ['yes'], 'od.odval1.val1': ['val1', 'val2']}
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == ['yes']
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).value.get() == None
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).owner.get() == owners.default
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st2val1', 0).value.set('no')
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == ['yes']
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).value.get() == 'no'
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).owner.get() == owner
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st1val1').value.pop(0)
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    cfg.option('od.stval1.st1val1.st2val1', 0).value.set('yes')
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).owner.get() == owner
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st2val1', 0).value.reset()
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).owner.get() == owners.default
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    cfg.option('od.stval1.st1val1.st2val1', 0).value.set('yes')
+    cfg.option('od.stval1.st1val1.st1val1').value.reset()
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owners.default
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+
+
+def test_masterslaves_default_multi_dyndescription():
+    st1 = StrOption('st1', "", multi=True)
+    st2 = StrOption('st2', "", multi=True, default_multi='no')
+    stm = MasterSlaves('st1', '', [st1, st2])
+    st = DynOptionDescription('st', '', [stm], callback=return_list)
+    od = OptionDescription('od', '', [st])
+    od2 = OptionDescription('od', '', [od])
+    api = Config(od2)
+    owner = api.owner.get()
+    #
+    assert api.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert api.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert api.option('od.stval1.st1val1.st1val1').owner.isdefault()
+    assert api.option('od.stval2.st1val2.st1val2').owner.isdefault()
+    #
+    api.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    assert api.option('od.stval1.st1val1.st1val1').value.get() == ['yes']
+    assert api.option('od.stval1.st1val1.st2val1', 0).value.get() == 'no'
+    assert api.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert api.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert api.option('od.stval1.st1val1.st2val1', 0).owner.isdefault()
+    assert api.option('od.stval2.st1val2.st1val2').owner.isdefault()
+
+
+def _test_masterslaves(cfg):
+    owner = cfg.owner.get()
+    cfg.option('od.val1.val1').value.set(['val1', 'val2'])
+    cfg.option('od.val1.val2', 0).value.set('val1')
+    cfg.option('od.val1.val2', 1).value.set('val2')
+    assert cfg.option.make_dict() == {'od.stval1.st1val1.st2val1': [], 'od.stval2.st1val2.st2val2': [], 'od.stval2.st1val2.st1val2': [], 'od.stval1.st1val1.st1val1': [], 'od.val1.val1': ['val1', 'val2'], 'od.val1.val2': ['val1', 'val2']}
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owners.default
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    assert cfg.option.make_dict() == {'od.stval1.st1val1.st2val1': [None], 'od.stval2.st1val2.st2val2': [], 'od.stval2.st1val2.st1val2': [], 'od.stval1.st1val1.st1val1': ['yes'], 'od.val1.val1': ['val1', 'val2'], 'od.val1.val2': ['val1', 'val2']}
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == ['yes']
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).value.get() == None
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).owner.get() == owners.default
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st2val1', 0).value.set('no')
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == ['yes']
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).value.get() == 'no'
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).owner.get() == owner
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st1val1').value.pop(0)
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    cfg.option('od.stval1.st1val1.st2val1', 0).value.set('yes')
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).owner.get() == owner
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st2val1', 0).value.reset()
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert cfg.option('od.stval1.st1val1.st2val1', 0).owner.get() == owners.default
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+    #
+    cfg.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    cfg.option('od.stval1.st1val1.st2val1', 0).value.set('yes')
+    cfg.option('od.stval1.st1val1.st1val1').value.reset()
+    assert cfg.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert cfg.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert cfg.option('od.stval1.st1val1.st1val1').owner.get() == owners.default
+    assert cfg.option('od.stval2.st1val2.st1val2').owner.get() == owners.default
+
+
+def test_masterslaves_dyndescription_param_master():
+    val1 = StrOption('val1', "", multi=True)
+    val2 = StrOption('val2', "", multi=True)
+    odval = MasterSlaves('val1', '', [val1, val2])
+    st1 = StrOption('st1', "", multi=True)
+    st2 = StrOption('st2', "", multi=True)
+    stm = MasterSlaves('st1', '', [st1, st2])
+    st = DynOptionDescription('st', '', [stm], callback=return_list, callback_params=Params(ParamOption(val1)))
+    od = OptionDescription('od', '', [st, odval])
+    od2 = OptionDescription('od', '', [od])
+    cfg = Config(od2)
+    _test_masterslaves(cfg)
+
+
+def test_masterslaves_default_multi_dyndescription():
+    st1 = StrOption('st1', "", multi=True)
+    st2 = StrOption('st2', "", multi=True, default_multi='no')
+    stm = MasterSlaves('st1', '', [st1, st2])
+    st = DynOptionDescription('st', '', [stm], callback=return_list)
+    od = OptionDescription('od', '', [st])
+    od2 = OptionDescription('od', '', [od])
+    api = Config(od2)
+    owner = api.owner.get()
+    #
+    assert api.option('od.stval1.st1val1.st1val1').value.get() == []
+    assert api.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert api.option('od.stval1.st1val1.st1val1').owner.isdefault()
+    assert api.option('od.stval2.st1val2.st1val2').owner.isdefault()
+    #
+    api.option('od.stval1.st1val1.st1val1').value.set(['yes'])
+    assert api.option('od.stval1.st1val1.st1val1').value.get() == ['yes']
+    assert api.option('od.stval1.st1val1.st2val1', 0).value.get() == 'no'
+    assert api.option('od.stval2.st1val2.st1val2').value.get() == []
+    assert api.option('od.stval1.st1val1.st1val1').owner.get() == owner
+    assert api.option('od.stval1.st1val1.st2val1', 0).owner.isdefault()
+    assert api.option('od.stval2.st1val2.st1val2').owner.isdefault()
+
+
+def test_masterslaves_dyndescription_param_slave():
+    val1 = StrOption('val1', "", multi=True)
+    val2 = StrOption('val2', "", multi=True)
+    odval = MasterSlaves('val1', '', [val1, val2])
+    st1 = StrOption('st1', "", multi=True)
+    st2 = StrOption('st2', "", multi=True)
+    stm = MasterSlaves('st1', '', [st1, st2])
+    st = DynOptionDescription('st', '', [stm], callback=return_list, callback_params=Params(ParamOption(val2)))
+    od = OptionDescription('od', '', [st, odval])
+    od2 = OptionDescription('od', '', [od])
+    cfg = Config(od2)
+    _test_masterslaves(cfg)
+
+
 def test_masterslaves_default_multi_dyndescription():
     st1 = StrOption('st1', "", multi=True)
     st2 = StrOption('st2', "", multi=True, default_multi='no')
diff --git a/tiramisu/autolib.py b/tiramisu/autolib.py
index fdff42a..4736a53 100644
--- a/tiramisu/autolib.py
+++ b/tiramisu/autolib.py
@@ -24,7 +24,6 @@ from typing import Any, Optional, Union, Callable, Dict, List
 from .error import PropertiesOptionError, ConfigError, SlaveError
 from .i18n import _
 from .setting import undefined, ConfigBag, OptionBag, Undefined
-from .option.symlinkoption import DynSymLinkOption
 from .storage import get_default_values_storages, get_default_settings_storages
 from .function import ParamValue, ParamContext, ParamIndex, ParamOption, Params
 # ____________________________________________________________
@@ -48,13 +47,7 @@ def manager_callback(callbk: Union[ParamOption, ParamValue],
         return context.duplicate(force_values=get_default_values_storages(),
                                  force_settings=get_default_settings_storages())
     opt = callbk.option
-    if opt.issubdyn():
-        opt = DynSymLinkOption(opt,
-                               option._rootpath,
-                               option.impl_getsuffix())
-        path = opt.impl_getpath(context)
-    else:
-        path = context.cfgimpl_get_description().impl_get_path_by_opt(opt)
+    path = opt.impl_getpath(context)
     if index is not None and opt.impl_is_master_slaves() and \
             opt.impl_get_master_slaves().in_same_group(option):
         if opt == option:
diff --git a/tiramisu/config.py b/tiramisu/config.py
index 9090f06..54b8b4a 100644
--- a/tiramisu/config.py
+++ b/tiramisu/config.py
@@ -123,7 +123,8 @@ class SubConfig(object):
         for woption in option_bag.option._get_dependencies(self):
             option = woption()
             if option.impl_is_dynoptiondescription():
-                for doption in option.get_syndynoptiondescriptions(option_bag):
+                for doption in option.get_syndynoptiondescriptions(option_bag,
+                                                                   remove_none=True):
                     doption_path = doption.impl_getpath(self)
                     doption_bag = OptionBag()
                     doption_bag.set_option(doption,
diff --git a/tiramisu/option/__init__.py b/tiramisu/option/__init__.py
index 214b2e1..e22f41f 100644
--- a/tiramisu/option/__init__.py
+++ b/tiramisu/option/__init__.py
@@ -3,7 +3,8 @@ from .dynoptiondescription import DynOptionDescription
 from .syndynoptiondescription import SynDynOptionDescription
 from .masterslave import MasterSlaves
 from .baseoption import submulti
-from .symlinkoption import SymLinkOption, DynSymLinkOption
+from .symlinkoption import SymLinkOption
+from .dynsymlinkoption import DynSymLinkOption
 from .option import Option, RegexpOption
 from .choiceoption import ChoiceOption
 from .booloption import BoolOption
diff --git a/tiramisu/option/baseoption.py b/tiramisu/option/baseoption.py
index 19f5d6a..e540cb5 100644
--- a/tiramisu/option/baseoption.py
+++ b/tiramisu/option/baseoption.py
@@ -28,6 +28,7 @@ from ..i18n import _
 from ..setting import undefined
 from ..error import ConfigError, display_list
 from ..function import Params, ParamContext, ParamOption, ParamIndex
+from .dynsymlinkoption import DynSymLinkOption
 
 STATIC_TUPLE = frozenset()
 
@@ -450,6 +451,13 @@ class BaseOption(Base):
 class OnlyOption(BaseOption):
     __slots__ = tuple()
 
+    def impl_get_dynoption(self,
+                           rootpath,
+                           suffix):
+        return DynSymLinkOption(self,
+                                rootpath,
+                                suffix)
+
 
 def validate_requires_arg(new_option,
                           multi,
diff --git a/tiramisu/option/dynoptiondescription.py b/tiramisu/option/dynoptiondescription.py
index c15643d..d819045 100644
--- a/tiramisu/option/dynoptiondescription.py
+++ b/tiramisu/option/dynoptiondescription.py
@@ -71,8 +71,9 @@ class DynOptionDescription(OptionDescription):
             raise ConfigError(_('callback is mandatory for the dynoptiondescription "{}"'
                                 '').format(self.impl_get_display_name()))
 
-    def _impl_get_suffixes(self,
-                           option_bag):
+    def impl_get_suffixes(self,
+                          option_bag,
+                          remove_none=False):
         callback, callback_params = self.impl_get_callback()
         values = carry_out_calculation(self,
                                        option_bag.config_bag.context,
@@ -83,18 +84,30 @@ class DynOptionDescription(OptionDescription):
         if not isinstance(values, list):
             raise ValueError(_('DynOptionDescription callback for option "{}", is not a list ({})'
                                '').format(self.impl_get_display_name(), values))
-        if len(values) > len(set(values)):
-            raise ValueError(_('DynOptionDescription callback return not unique value'))
+        values_ = []
         for val in values:
             if not isinstance(val, str) or re.match(NAME_REGEXP, val) is None:
-                raise ValueError(_('invalid suffix "{}" for option "{}"'
-                                   '').format(val,
-                                              self.impl_get_display_name()))
-        return values
+                if not remove_none or val is not None:
+                    raise ValueError(_('invalid suffix "{}" for option "{}"'
+                                       '').format(val,
+                                                  self.impl_get_display_name()))
+            else:
+                values_.append(val)
+        values = values_
+        if len(values) > len(set(values)):
+            extra_values = values.copy()
+            for val in set(values):
+                extra_values.remove(val)
+            raise ValueError(_('DynOptionDescription callback return a list with multiple value '
+                               '"{}"''').format(extra_values))
+        return values_
 
-    def get_syndynoptiondescriptions(self, option_bag):
+    def get_syndynoptiondescriptions(self,
+                                     option_bag,
+                                     remove_none=False):
         subpath = self.impl_getpath(option_bag.config_bag.context).rsplit('.', 1)[0]
-        for suffix in self._impl_get_suffixes(option_bag):
+        for suffix in self.impl_get_suffixes(option_bag,
+                                             remove_none=remove_none):
             yield SynDynOptionDescription(self,
                                           subpath,
                                           suffix)
diff --git a/tiramisu/option/dynsymlinkoption.py b/tiramisu/option/dynsymlinkoption.py
new file mode 100644
index 0000000..86e0c8b
--- /dev/null
+++ b/tiramisu/option/dynsymlinkoption.py
@@ -0,0 +1,83 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2018 Team tiramisu (see AUTHORS for all contributors)
+#
+# This program is free software: you can redistribute it and/or modify it
+# under the terms of the GNU Lesser General Public License as published by the
+# Free Software Foundation, either version 3 of the License, or (at your
+# option) any later version.
+#
+# This program is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
+# details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+# The original `Config` design model is unproudly borrowed from
+# the rough pypy's guys: http://codespeak.net/svn/pypy/dist/pypy/config/
+# the whole pypy projet is under MIT licence
+# ____________________________________________________________
+from ..setting import undefined, OptionBag
+
+
+class DynSymLinkOption(object):
+    __slots__ = ('_rootpath', 
+                 '_opt',
+                 '_suffix')
+
+    def __init__(self,
+                 opt,
+                 rootpath,
+                 suffix):
+        self._opt = opt
+        self._rootpath = rootpath
+        self._suffix = suffix
+
+    def __getattr__(self,
+                    name):
+        return getattr(self._opt, name)
+
+    def __eq__(self, left):
+        if not isinstance(left, DynSymLinkOption):
+            return False
+        return self._opt == left._opt and \
+                self._rootpath == left._rootpath and \
+                self._suffix == left._suffix
+
+    def impl_getname(self):
+        return self._opt.impl_getname() + self._suffix
+
+    def impl_get_display_name(self):
+        return self._opt.impl_get_display_name(dyn_name=self.impl_getname())
+
+    def impl_getopt(self):
+        return self._opt
+
+    def impl_getsuffix(self):
+        return self._suffix
+
+    def impl_getpath(self,
+                     context):
+        return self._rootpath + '.' + self.impl_getname()
+
+    def impl_validate(self,
+                      value,
+                      option_bag,
+                      context=undefined,
+                      check_error=True):
+        context = option_bag.config_bag.context
+        soption_bag = OptionBag()
+        soption_bag.set_option(self._opt,
+                               self.impl_getpath(context),
+                               option_bag.index,
+                               option_bag.config_bag)
+        soption_bag.ori_option = option_bag.option
+        soption_bag.fromconsistency = option_bag.fromconsistency.copy()
+        self._opt.impl_validate(value,
+                                soption_bag,
+                                context=context,
+                                check_error=check_error)
+
+    def impl_is_dynsymlinkoption(self):
+        return True
diff --git a/tiramisu/option/option.py b/tiramisu/option/option.py
index fce60f3..f478cce 100644
--- a/tiramisu/option/option.py
+++ b/tiramisu/option/option.py
@@ -23,7 +23,6 @@ import warnings
 import weakref
 
 from .baseoption import OnlyOption, submulti, STATIC_TUPLE
-from .symlinkoption import DynSymLinkOption
 from ..i18n import _
 from ..setting import log, undefined, debug, OptionBag
 from ..autolib import carry_out_calculation
@@ -457,7 +456,7 @@ class Option(OnlyOption):
             if descr._cache_consistencies is None:
                 return
             # get consistencies for this option
-            if isinstance(option_bag.option, DynSymLinkOption):
+            if option_bag.option.impl_is_dynsymlinkoption():
                 consistencies = descr._cache_consistencies.get(option_bag.option.impl_getopt())
             else:
                 consistencies = descr._cache_consistencies.get(option_bag.option)
@@ -475,12 +474,11 @@ class Option(OnlyOption):
                 if (warnings_only and not check_error) or (not warnings_only and check_error):
                     transitive = params.get('transitive', True)
                     #all_cons_opts[0] is the option where func is set
-                    if isinstance(option_bag.ori_option, DynSymLinkOption):
+                    if option_bag.ori_option.impl_is_dynsymlinkoption():
                         opts = []
                         for opt in all_cons_opts:
-                            opts.append(DynSymLinkOption(opt(),
-                                                         option_bag.ori_option._rootpath,
-                                                         option_bag.ori_option._suffix))
+                            opts.append(opt().impl_get_dynoption(option_bag.ori_option._rootpath,
+                                                                 option_bag.ori_option._suffix))
                         wopt = opts[0]
                     else:
                         opts = all_cons_opts
diff --git a/tiramisu/option/optiondescription.py b/tiramisu/option/optiondescription.py
index e83f635..55a5ef1 100644
--- a/tiramisu/option/optiondescription.py
+++ b/tiramisu/option/optiondescription.py
@@ -24,7 +24,7 @@ from copy import copy
 from ..i18n import _
 from ..setting import ConfigBag, OptionBag, groups, undefined, owners
 from .baseoption import BaseOption, OnlyOption
-from .option import ALLOWED_CONST_LIST, DynSymLinkOption
+from .option import ALLOWED_CONST_LIST
 from .syndynoptiondescription import SynDynOptionDescription
 from ..error import ConfigError, ConflictError
 
@@ -234,12 +234,11 @@ class OptionDescriptionWalk(CacheOptionDescription):
         ori_index = len(rootpath) + 1
         subpaths = [rootpath] + option.impl_getpath(
                 option_bag.config_bag.context)[ori_index:].split('.')[:-1]
-        for suffix in dynopt._impl_get_suffixes(option_bag):
+        for suffix in dynopt.impl_get_suffixes(option_bag):
             subpath = '.'.join([subp + suffix for subp in subpaths])
             if isinstance(option, OnlyOption):
-                yield DynSymLinkOption(option,
-                                       subpath,
-                                       suffix)
+                yield option.impl_get_dynoption(subpath,
+                                                suffix)
             else:
                 yield SynDynOptionDescription(option,
                                               subpath,
@@ -333,7 +332,7 @@ class OptionDescriptionWalk(CacheOptionDescription):
                                       subpath,
                                       None,
                                       config_bag)
-                for suffix in child._impl_get_suffixes(option_bag):
+                for suffix in child.impl_get_suffixes(option_bag):
                     yield SynDynOptionDescription(child,
                                                   subpath,
                                                   suffix)
@@ -360,7 +359,7 @@ class OptionDescriptionWalk(CacheOptionDescription):
                                       subconfig.cfgimpl_get_path(),
                                       None,
                                       config_bag)
-                for value in child._impl_get_suffixes(option_bag):
+                for value in child.impl_get_suffixes(option_bag):
                     if name == cname + value:
                         return SynDynOptionDescription(child,
                                                        subconfig.cfgimpl_get_path(),
@@ -375,9 +374,8 @@ class OptionDescriptionWalk(CacheOptionDescription):
                                            subpath,
                                            suffix)
         else:
-            return DynSymLinkOption(child,
-                                    subpath,
-                                    suffix)
+            return child.impl_get_dynoption(subpath,
+                                            suffix)
 
 
 class OptionDescription(OptionDescriptionWalk):
diff --git a/tiramisu/option/symlinkoption.py b/tiramisu/option/symlinkoption.py
index 1b50496..b3c31ad 100644
--- a/tiramisu/option/symlinkoption.py
+++ b/tiramisu/option/symlinkoption.py
@@ -20,7 +20,6 @@
 # ____________________________________________________________
 from .baseoption import OnlyOption
 from ..i18n import _
-from ..setting import undefined, OptionBag
 
 
 class SymLinkOption(OnlyOption):
@@ -60,65 +59,3 @@ class SymLinkOption(OnlyOption):
 
     def get_consistencies(self):
         return ()
-
-
-class DynSymLinkOption(object):
-    __slots__ = ('_rootpath', 
-                 '_opt',
-                 '_suffix')
-
-    def __init__(self,
-                 opt,
-                 rootpath,
-                 suffix):
-        self._opt = opt
-        self._rootpath = rootpath
-        self._suffix = suffix
-
-    def __getattr__(self,
-                    name):
-        return getattr(self._opt, name)
-
-    def __eq__(self, left):
-        if not isinstance(left, DynSymLinkOption):
-            return False
-        return self._opt == left._opt and \
-                self._rootpath == left._rootpath and \
-                self._suffix == left._suffix
-
-    def impl_getname(self):
-        return self._opt.impl_getname() + self._suffix
-
-    def impl_get_display_name(self):
-        return self._opt.impl_get_display_name(dyn_name=self.impl_getname())
-
-    def impl_getopt(self):
-        return self._opt
-
-    def impl_getsuffix(self):
-        return self._suffix
-
-    def impl_getpath(self,
-                     context):
-        return self._rootpath + '.' + self.impl_getname()
-
-    def impl_validate(self,
-                      value,
-                      option_bag,
-                      context=undefined,
-                      check_error=True):
-        context = option_bag.config_bag.context
-        soption_bag = OptionBag()
-        soption_bag.set_option(self._opt,
-                               self.impl_getpath(context),
-                               option_bag.index,
-                               option_bag.config_bag)
-        soption_bag.ori_option = option_bag.option
-        soption_bag.fromconsistency = option_bag.fromconsistency.copy()
-        self._opt.impl_validate(value,
-                                soption_bag,
-                                context=context,
-                                check_error=check_error)
-
-    def impl_is_dynsymlinkoption(self):
-        return True
diff --git a/tiramisu/option/syndynoptiondescription.py b/tiramisu/option/syndynoptiondescription.py
index 83a83d6..004b2a4 100644
--- a/tiramisu/option/syndynoptiondescription.py
+++ b/tiramisu/option/syndynoptiondescription.py
@@ -20,7 +20,6 @@
 # ____________________________________________________________
 from ..i18n import _
 from ..setting import groups, undefined
-from .symlinkoption import DynSymLinkOption
 
 
 class SynDynOptionDescription(object):
@@ -81,16 +80,20 @@ class SynDynOptionDescription(object):
 
     def getmaster(self):
         master = self._opt.getmaster()
-        return DynSymLinkOption(master,
-                                self.impl_getpath(None),
-                                self._suffix)
+        return master.impl_get_dynoption(self.impl_getpath(None),
+                                         self._suffix)
 
     def getslaves(self):
         subpath = self.impl_getpath(None)
         for slave in self._opt.getslaves():
-            yield DynSymLinkOption(slave,
-                                   subpath,
-                                   self._suffix)
+            yield slave.impl_get_dynoption(subpath,
+                                           self._suffix)
+
+    def impl_get_display_name(self):
+        return self._opt.impl_get_display_name() + self._suffix
+
+    def impl_getdoc(self):
+        return self._opt.impl_getdoc() + self._suffix
 
     def reset_cache(self,
                     path,
diff --git a/tiramisu/setting.py b/tiramisu/setting.py
index d71775f..ba1411c 100644
--- a/tiramisu/setting.py
+++ b/tiramisu/setting.py
@@ -484,8 +484,11 @@ class Settings(object):
                 exps, action, inverse, transitive, same_action, operator = require
                 breaked = False
                 for option, expected in exps:
+                    if option.issubdyn():
+                        option = option.impl_get_dynoption(option_bag.option._rootpath,
+                                                           option_bag.option.impl_getsuffix())
                     reqpath = option.impl_getpath(context)
-                    #FIXME c'est un peu tard !
+                    #FIXME too later!
                     if reqpath.startswith(option_bag.path + '.'):
                         raise RequirementError(_("malformed requirements "
                                                  "imbrication detected for option:"