--- a/hgext3rd/evolve/__init__.py	Thu Oct 19 21:23:21 2017 +0200
+++ b/hgext3rd/evolve/__init__.py	Thu Oct 19 14:46:06 2017 +0200
@@ -374,6 +374,15 @@
 extsetup = eh.final_extsetup
 reposetup = eh.final_reposetup
 cmdtable = eh.cmdtable
+configtable = eh.configtable
+
+# Configuration
+eh.configitem('experimental', 'evolutioncommands')
+eh.configitem('experimental', 'evolution.allnewcommands')
+eh.configitem('experimental', 'prunestrip')
+
+# hack around because we need an actual default there
+configtable['experimental']['evolution.allnewcommands'].default = None
 
 # pre hg 4.0 compat
 
@@ -418,7 +427,7 @@
     # This must be in the same function as the option configuration above to
     # guarantee it happens after the above configuration, but before the
     # extsetup functions.
-    evolvecommands = ui.configlist('experimental', 'evolutioncommands')
+    evolvecommands = ui.configlist('experimental', 'evolutioncommands', [])
     evolveopts = ui.configlist('experimental', 'evolution')
     if evolveopts and (commandopt not in evolveopts and
                        'all' not in evolveopts):
@@ -2247,7 +2256,7 @@
                            "backup bundle")),
     ])
 def stripwrapper(orig, ui, repo, *revs, **kwargs):
-    if (not ui.configbool('experimental', 'prunestrip') or
+    if (not ui.configbool('experimental', 'prunestrip', False) or
         kwargs.get('bundle', False)):
         return orig(ui, repo, *revs, **kwargs)
 

--- a/hgext3rd/evolve/exthelper.py	Thu Oct 19 21:23:21 2017 +0200
+++ b/hgext3rd/evolve/exthelper.py	Thu Oct 19 14:46:06 2017 +0200
@@ -17,6 +17,13 @@
     from mercurial import cmdutil
     command = cmdutil.command
 
+configitem = None
+dynamicdefault = None
+if util.safehasattr(registrar, 'configitem'):
+    configitem = registrar.configitem
+    from mercurial import configitems
+    dynamicdefault = configitems.dynamicdefault
+
 class exthelper(object):
     """Helper for modular extension setup
 
@@ -39,6 +46,22 @@
         self.cmdtable = {}
         self.command = command(self.cmdtable)
 
+        self.configtable = {}
+        self._configitem = None
+        if configitem is not None:
+            self._configitem = configitem(self.configtable)
+
+    def configitem(self, section, config):
+        """For Mercurial 4.4 and above, register a config item
+
+        For now constraint to 'dynamicdefault' until we only support version with the feature.
+        Older version would otherwise not use the declare default.
+
+        For older version no-op fallback for old Mercurial versions
+        """
+        if self._configitem is not None:
+            self._configitem(section, config, default=dynamicdefault)
+
     def merge(self, other):
         self._uicallables.extend(other._uicallables)
         self._extcallables.extend(other._extcallables)
@@ -50,6 +73,11 @@
         self._functionwrappers.extend(other._functionwrappers)
         self._duckpunchers.extend(other._duckpunchers)
         self.cmdtable.update(other.cmdtable)
+        for section, items in other.configtable.iteritems():
+            if section in self.configtable:
+                self.configtable[section].update(items)
+            else:
+                self.configtable[section] = items
 
     def final_uisetup(self, ui):
         """Method to be used as the extension uisetup

--- a/hgext3rd/evolve/obsdiscovery.py	Thu Oct 19 21:23:21 2017 +0200
+++ b/hgext3rd/evolve/obsdiscovery.py	Thu Oct 19 14:46:06 2017 +0200
@@ -72,6 +72,13 @@
 eh.merge(stablerange.eh)
 obsexcmsg = utility.obsexcmsg
 
+# Config
+eh.configitem('experimental', 'evolution.obsdiscovery')
+eh.configitem('experimental', 'obshashrange')
+eh.configitem('experimental', 'obshashrange.warm-cache')
+eh.configitem('experimental', 'obshashrange.max-revs')
+eh.configitem('experimental', 'obshashrange.lru-size')
+
 ##################################
 ###  Code performing discovery ###
 ##################################

--- a/hgext3rd/evolve/obsexchange.py	Thu Oct 19 21:23:21 2017 +0200
+++ b/hgext3rd/evolve/obsexchange.py	Thu Oct 19 14:46:06 2017 +0200
@@ -44,6 +44,7 @@
 obsexcmsg = utility.obsexcmsg
 obsexcprg = utility.obsexcprg
 
+eh.configitem('experimental', 'verbose-obsolescence-exchange')
 
 _bestformat = max(obsolete.formats.keys())
 

--- a/hgext3rd/evolve/obshistory.py	Thu Oct 19 21:23:21 2017 +0200
+++ b/hgext3rd/evolve/obshistory.py	Thu Oct 19 14:46:06 2017 +0200
@@ -30,6 +30,18 @@
 
 eh = exthelper.exthelper()
 
+# Config
+efd = {'default': True} # pass a default value unless the config is registered
+
+@eh.extsetup
+def enableeffectflags(ui):
+    item = (getattr(ui, '_knownconfig', {})
+            .get('experimental', {})
+            .get('evolution.effect-flags'))
+    if item is not None:
+        item.default = True
+        efd.clear()
+
 @eh.command(
     'obslog|olog',
     [('G', 'graph', True, _("show the revision DAG")),
@@ -634,7 +646,7 @@
     meaningful data. In the future, we can introduce way for commands to
     provide precomputed effect to avoid the overhead.
     """
-    if not repo.ui.configbool('experimental', 'evolution.effect-flags', True):
+    if not repo.ui.configbool('experimental', 'evolution.effect-flags', **efd):
         return orig(repo, relations, flag, date, metadata, **kwargs)
     if metadata is None:
         metadata = {}

--- a/hgext3rd/evolve/safeguard.py	Thu Oct 19 21:23:21 2017 +0200
+++ b/hgext3rd/evolve/safeguard.py	Thu Oct 19 14:46:06 2017 +0200
@@ -16,6 +16,8 @@
 
 eh = exthelper.exthelper()
 
+eh.configitem('experimental', 'auto-publish')
+
 @eh.reposetup
 def setuppublishprevention(ui, repo):
 

--- a/hgext3rd/evolve/serveronly.py	Thu Oct 19 21:23:21 2017 +0200
+++ b/hgext3rd/evolve/serveronly.py	Thu Oct 19 14:46:06 2017 +0200
@@ -47,6 +47,7 @@
 extsetup = eh.final_extsetup
 reposetup = eh.final_reposetup
 cmdtable = eh.cmdtable
+configtable = eh.configtable
 
 @eh.reposetup
 def default2evolution(ui, repo):