diff -ur v4/fsyn.py v5/fsyn.py
--- v4/fsyn.py	2020-04-26 17:39:47.000000000 +0900
+++ v5/fsyn.py	2020-04-29 20:50:21.000000000 +0900
@@ -17,7 +17,7 @@
 
 to_str = base.to_str
 msg_done = lambda done, targ: dbg.out( '{} {}'.format( done, targ ) )
-cmd_call = lambda cmd: cmd_ut.call( cmd, b2s=True )
+cmd_call = lambda cmd, dv='': cmd_ut.call( cmd, dv, b2s=True )
 cmd_lst = lambda cmd: sorted( cmd_call( cmd ).strip().split('\n') )
 
 def confirm(msg):
@@ -71,6 +71,10 @@
 
 	def put_link(id, link, dir_=None):
 		fn = id_fn( id, 'link', dir_ )
+		(DIR, BASE) = os.path.split( fn )
+		if not path_exists( DIR ):
+			cmd = 'mkdir -p ' + DIR
+			cmd_call( cmd )
 		d = vars( link )
 		yaml_ut.save( d, fn )
 
@@ -316,14 +320,48 @@
 		for id in id_lst:
 			fix_link( id )
 
+	# site ut
+
+	(fsyn_DIR, fsyn_BASE) = os.path.split( fsyn_path() )
+
+	get_site_ut_cmd = ( lambda cmd, fn, cd_dir=fsyn_DIR:
+		'( cd {} ; python -m site_ut {} -C {} {} )'.format( fsyn_DIR, cmd, cd_dir, fn ) )
+
+	def site_exists(fn):
+		cmd = get_site_ut_cmd( 'exists', fn )
+		return cmd_call( cmd, 'err' ) != 'err'
+
+	def site_get_link(id):
+		fn = path_join( fsyn_BASE, id, 'link' )
+		if site_exists( fn ):
+			cmd = get_site_ut_cmd( 'cat', fn )
+			d = yaml_ut.load( cmd_call( cmd ) )
+			return empty.new( d )
+		return empty.new( from_='', to=[] ) # !
+
+	def com_exists(path, fn):
+		if path == 'site_ut':
+			return site_exists( fn )
+		return path_exists( path_join( path, fn ) )
+
+	def com_get_link(id, dir_=None):
+		if dir_ == 'site_ut':
+			return site_get_link( id )
+		return get_link(id, dir_)
+
+
+
 	def push(to_path):
-		(fsyn_DIR, fsyn_BASE) = os.path.split( fsyn_path() )
+		from_path = to_path
+		if to_path == 'site_ut':
+			from_path = 'site_ut'
+			to_path = cmd_ut.mk_tmp_dir( '/tmp/fsyn_' )
 
 		def copy(id, name, force=False):
 			fn = path_join( fsyn_BASE, id, name )
 			if not path_exists( path_join( fsyn_DIR, fn ) ):
 				return # no src
-			if not path_exists( path_join( to_path, fn ) ) or force:
+			if not com_exists( from_path, fn ) or force:
 				cmd = 'tar cf - -C {} {} | tar xf - -C {}'.format( fsyn_DIR, fn, to_path )
 				cmd_call( cmd )
 
@@ -334,12 +372,19 @@
 			link = get_link( id )
 			if link_lmt:
 				link.to = list( filter( lambda s: s == link_lmt, link.to ) )
-			link_d = get_link( id, to_path )
-			link_d.from_ = link.from_
+
+			link_d = com_get_link( id, from_path )
+
+			dirty = False
+			if link_d.from_ != link.from_:
+				link_d.from_ = link.from_
+				dirty = True
 			for s in link.to:
 				if s not in link_d.to:
 					link_d.to.append( s )
-			put_link( id, link_d, to_path )
+					dirty = True
+			if dirty:
+				put_link( id, link_d, to_path )
 
 		def push_to(id):
 			push_id( id )
@@ -353,22 +398,29 @@
 
 		push_to( get_curr() )
 
+		if from_path == 'site_ut':
+			cmd = get_site_ut_cmd( 'put', fsyn_BASE, cd_dir=to_path )
+			dbg.out( 'upload cmd={} ... '.format( cmd ), '' )
+			cmd_call( cmd )
+			cmd_ut.rm_rf( to_path )
+			dbg.out( 'ok' )
+
 	def pull(from_path):
-		(fsyn_DIR, fsyn_BASE) = os.path.split( fsyn_path() )
-		
 		def copy(id, name, force=False):
 			fn = path_join( fsyn_BASE, id, name )
-			if not path_exists( path_join( from_path, fn ) ):
+			if not com_exists( from_path, fn ):
 				return # no src
 			if not path_exists( path_join( fsyn_DIR, fn ) ) or force:
 				cmd = 'tar cf - -C {} {} | tar xf - -C {}'.format( from_path, fn, fsyn_DIR )
+				if from_path == 'site_ut': # !!!
+					cmd = get_site_ut_cmd( 'get', fn )
 				cmd_call( cmd )
 
 		def pull_id(id):
 			copy( id, 'snap' )
 			copy( id, 'update.tgz' )
 
-			link = get_link( id, from_path )
+			link = com_get_link( id, from_path )
 			link_d = get_link( id )
 			link_d.from_ = link.from_
 			for s in link.to:
@@ -378,12 +430,12 @@
 
 		def pull_from(id):
 			pull_id( id )
-			link = get_link( id, from_path )
+			link = com_get_link( id, from_path )
 			for s in link.to:
 				pull_from( s )
 
 		id = get_curr()
-		if path_exists( path_join( from_path, fsyn_BASE, id ) ):
+		if com_exists( from_path, path_join( fsyn_BASE, id, 'snap' ) ): # ! link
 			pull_from( id )