diff --git a/support/hg/arc-hg.py b/support/hg/arc-hg.py
index 70dad19f..a11cef73 100644
--- a/support/hg/arc-hg.py
+++ b/support/hg/arc-hg.py
@@ -1,190 +1,185 @@
 from __future__ import absolute_import
 
 import os
 import json
 
 from mercurial import (
   cmdutil,
   bookmarks,
   bundlerepo,
   error,
   hg,
   i18n,
   node,
   registrar,
 )
 
 _ = i18n._
 cmdtable = {}
 command = registrar.command(cmdtable)
 
 @command(
   "arc-ls-markers",
   [('', 'output', '',
     _('file to output refs to'), _('FILE')),
   ] + cmdutil.remoteopts,
   _('[--output FILENAME] [SOURCE]'))
 def lsmarkers(ui, repo, source=None, **opts):
   """list markers
 
   Show the current branch heads and bookmarks in the local working copy, or
   a specified path/URL.
 
   Markers are printed to stdout in JSON.
 
   (This is an Arcanist extension to Mercurial.)
 
   Returns 0 if listing the markers succeeds, 1 otherwise.
   """
 
   if source is None:
     markers = localmarkers(ui, repo)
   else:
     markers = remotemarkers(ui, repo, source, opts)
 
   json_opts = {
     'indent': 2,
     'sort_keys': True,
   }
 
   output_file = opts.get('output')
   if output_file:
     if os.path.exists(output_file):
       raise error.Abort(_('File "%s" already exists.' % output_file))
     with open(output_file, 'w+') as f:
       json.dump(markers, f, **json_opts)
   else:
     print json.dumps(markers, output_file, **json_opts)
 
   return 0
 
 def localmarkers(ui, repo):
   markers = []
 
   active_node = repo['.'].node()
   all_heads = set(repo.heads())
   current_name = repo.dirstate.branch()
   saw_current = False
   saw_active = False
 
   branch_list = repo.branchmap().iterbranches()
   for branch_name, branch_heads, tip_node, is_closed in branch_list:
     for head_node in branch_heads:
       is_active = (head_node == active_node)
       is_tip = (head_node == tip_node)
       is_current = (branch_name == current_name)
 
       if is_current:
         saw_current = True
 
       if is_active:
         saw_active = True
 
       if is_closed:
         head_closed = True
       else:
         head_closed = bool(head_node not in all_heads)
 
       description = repo[head_node].description()
 
       markers.append({
         'type': 'branch',
         'name': branch_name,
         'node': node.hex(head_node),
         'isActive': is_active,
         'isClosed': head_closed,
         'isTip': is_tip,
         'isCurrent': is_current,
         'description': description,
       })
 
   # If the current branch (selected with "hg branch X") is not reflected in
   # the list of heads we selected, add a virtual head for it so callers get
   # a complete picture of repository marker state.
 
   if not saw_current:
     markers.append({
       'type': 'branch',
       'name': current_name,
       'node': None,
       'isActive': False,
       'isClosed': False,
       'isTip': False,
       'isCurrent': True,
       'description': None,
     })
 
   bookmarks = repo._bookmarks
   active_bookmark = repo._activebookmark
 
   for bookmark_name, bookmark_node in bookmarks.iteritems():
     is_active = (active_bookmark == bookmark_name)
     description = repo[bookmark_node].description()
 
     if is_active:
       saw_active = True
 
     markers.append({
       'type': 'bookmark',
       'name': bookmark_name,
       'node': node.hex(bookmark_node),
       'isActive': is_active,
       'description': description,
     })
 
   # If the current working copy state is not the head of a branch and there is
   # also no active bookmark, add a virtual marker for it so callers can figure
   # out exactly where we are.
 
   if not saw_active:
     markers.append({
       'type': 'commit',
       'name': None,
       'node': node.hex(active_node),
       'isActive': False,
       'isClosed': False,
       'isTip': False,
       'isCurrent': True,
       'description': repo['.'].description(),
     })
 
   return markers
 
 def remotemarkers(ui, repo, source, opts):
   # Disable status output from fetching a remote.
   ui.quiet = True
 
   markers = []
 
   source, branches = hg.parseurl(ui.expandpath(source))
   remote = hg.peer(repo, opts, source)
 
-  bundle, remotebranches, cleanup = bundlerepo.getremotechanges(
-    ui,
-    repo,
-    remote)
-
-  try:
-    for n in remotebranches:
-      ctx = bundle[n]
+  with remote.commandexecutor() as e:
+    branchmap = e.callcommand('branchmap', {}).result()
+
+  for branch_name in branchmap:
+    for branch_node in branchmap[branch_name]:
       markers.append({
         'type': 'branch',
-        'name': ctx.branch(),
-        'node': node.hex(ctx.node()),
+        'name': branch_name,
+        'node': node.hex(branch_node),
       })
-  finally:
-    cleanup()
 
   with remote.commandexecutor() as e:
     remotemarks = bookmarks.unhexlifybookmarks(e.callcommand('listkeys', {
-        'namespace': 'bookmarks',
+      'namespace': 'bookmarks',
     }).result())
 
   for mark in remotemarks:
     markers.append({
       'type': 'bookmark',
       'name': mark,
       'node': node.hex(remotemarks[mark]),
     })
 
   return markers