diff --git a/tools/hub-clone.py b/tools/hub-clone.py
index a37f532..f1d3615 100644
--- a/tools/hub-clone.py
+++ b/tools/hub-clone.py
@@ -1,94 +1,238 @@
 import os
+import stat
 import sys
+import time
 import requests
 
-if len(sys.argv) < 3:
-    print("")
-    print(f"  Usage: {sys.argv[0]} [remote-host] [local-directory]")
-    print("")
-    print("  Example:")
-    print(f"    {sys.argv[0]} https://hub.grid.tf /tmp/users")
-    print("")
+class HubFlistSyncer:
+    def __init__(self, baseurl, localdir):
+        self.baseurl = baseurl
+        self.localdir = localdir
 
-    sys.exit(1)
+        self.officials = []
 
-host = sys.argv[1]
-target = sys.argv[2]
-officials = []
-root = os.getcwd()
-download = 0
-files = 0
+        self.root = os.getcwd()
+        self.downloaded = 0
+        self.files = 0
 
-#
-# fetching repositories
-#
+    #
+    # remote helpers
+    #
+    def remote_repositories(self):
+        r = requests.get(f"{self.baseurl}/api/repositories")
+        repositories = r.json()
 
-r = requests.get(f"{host}/api/repositories")
-repositories = r.json()
+        return repositories
 
-for repo in repositories:
-    userpath = f"{target}/{repo['name']}"
+    def remote_repository(self, username):
+        sys.stdout.write(f"\r[+] fetching user informations: {username} \033\x5bK")
 
-    if not os.path.exists(userpath):
-        os.mkdir(userpath)
+        r = requests.get(f"{self.baseurl}/api/flist/{username}")
+        entries = r.json()
 
-    if repo['official']:
-        officials.append(repo['name'])
+        return entries
 
-print(f"[+] created: {len(repositories)} repositories")
+    #
+    # local helpers
+    #
+    def local_sync_repositories(self, repositories):
+        updated = []
 
-#
-# fetching flist for each repositories
-#
+        for repo in repositories:
+            userpath = f"{self.localdir}/{repo['name']}"
 
-for repo in repositories:
-    sys.stdout.write(f"\r[+] fetching user informations: {repo['name']} \033[K")
+            if repo['official']:
+                self.officials.append(repo['name'])
 
-    r = requests.get(f"{host}/api/flist/{repo['name']}")
-    entries = r.json()
-    for entry in entries:
-        targetfile = f"{target}/{repo['name']}/{entry['name']}"
+            if not os.path.exists(userpath):
+                os.mkdir(userpath)
+                os.utime(userpath, (int(time.time()), repo['updated']))
+                updated.append(repo)
+                continue
 
-        # skip if local file exists
-        # FIXME: should be updated if different
-        if os.path.exists(targetfile):
-            continue
+            dirstat = os.stat(userpath)
+            if repo['updated'] > int(dirstat.st_mtime):
+                updated.append(repo)
 
-        if entry['type'] == 'regular':
-            url = f"{host}/{repo['name']}/{entry['name']}"
-            sys.stdout.write(f"\r[+] downloading: {url} \033[K")
+            else:
+                # FIXME: force update for legacy purpose
+                os.utime(userpath, (int(time.time()), repo['updated']))
+
+        print(f"[+] {len(updated)} / {len(repositories)} local repositories to update")
+
+        return updated
 
-            r = requests.get(url)
-            with open(targetfile, "wb") as f:
-                f.write(r.content)
+    def local_sync_repository(self, username, entries, updated):
+        userpath = f"{self.localdir}/{username}"
 
-            download += len(r.content)
-            files += 1
+        for entry in entries:
+            targetfile = f"{self.localdir}/{username}/{entry['name']}"
+            self.local_sync_entryfile(username, entry, targetfile)
+
+        # update last modification time
+        os.utime(userpath, (int(time.time()), updated))
+
+    def local_sync_entryfile(self, username, entry, targetfile):
+        # FIXME: support deleted entries
+        # (need to compare extra local entries)
+
+        if entry['type'] == 'regular':
+            return self.local_sync_regular_file(username, entry, targetfile)
 
         if entry['type'] == 'symlink':
-            os.chdir(f"{target}/{repo['name']}")
+            return self.local_sync_symlink(username, entry, targetfile)
+
+        if entry['type'] == 'tag':
+            return self.local_sync_tag(username, entry, targetfile)
+
+        if entry['type'] == 'taglink':
+            return self.local_sync_taglink(username, entry, targetfile)
+
+        raise RuntimeError(f"Unexpected entry type: {entry['type']}")
 
-            if "/" in entry['target']:
-                os.symlink(f"../{entry['target']}", entry['name'])
+    #
+    # entry type specific handlers
+    #
+    def local_sync_regular_file(self, username, entry, targetfile):
+        now = int(time.time())
+
+        if os.path.lexists(targetfile):
+            filestat = os.lstat(targetfile)
+
+            # checking if local is a regular file as well
+            if stat.S_ISREG(filestat.st_mode):
+                # checking if remote file is newer
+                if entry['updated'] <= int(filestat.st_mtime):
+                    return None
 
             else:
-                os.symlink(entry['target'], entry['name'])
+                # local file is not a regular file and remote
+                # file is a regular file, removing local file and
+                # updating it
+                os.remove(targetfile)
 
-            os.chdir(root)
+        url = f"{self.baseurl}/{username}/{entry['name']}"
+        sys.stdout.write(f"\r[+] downloading: {url} \033\x5bK")
 
-        if entry['type'] == 'tag':
-            targetfile = f"{target}/{repo['name']}/.tag-{entry['name']}"
+        r = requests.get(url)
+        with open(targetfile, "wb") as f:
+            f.write(r.content)
 
-            if not os.path.exists(targetfile):
-                os.mkdir(targetfile)
+        # apply same modification time on symlink than remote host
+        os.utime(targetfile, (now, entry['updated']))
 
-        if entry['type'] == 'taglink':
-            items = entry['target'].split("/")
+        self.downloaded += len(r.content)
+        self.files += 1
+
+        return True
+
+    def local_sync_symlink(self, username, entry, targetfile):
+        now = int(time.time())
+
+        if os.path.lexists(targetfile):
+            filestat = os.lstat(targetfile)
+
+            # checking if local is a symlink as well
+            if stat.S_ISLNK(filestat.st_mode):
+                # checking if symlink is newer
+                if entry['linktime'] <= int(filestat.st_mtime):
+                    return None
+
+                # update required, removing local file
+                os.remove(targetfile)
+
+            else:
+                # local file is not a symlink and remote file
+                # is a symlink, updating
+                os.remove(targetfile)
+
+        os.chdir(f"{self.localdir}/{username}")
+        target = entry['target']
+
+        # checking for crosslink
+        if "/" in entry['target']:
+            target = f"../{entry['target']}"
+
+        os.symlink(target, entry['name'])
+        os.chdir(self.root)
+
+        # apply same modification time on the tag directory than remote host
+        os.utime(targetfile, (now, entry['linktime']), follow_symlinks=False)
+
+        return True
+
+    def local_sync_tag(self, username, entry, targetfile):
+        now = int(time.time())
+
+        # update targetfile with tag syntax
+        targetfile = f"{self.localdir}/{username}/.tag-{entry['name']}"
+
+        # ignoring last modification time and updating anyway
+        if not os.path.exists(targetfile):
+            os.mkdir(targetfile)
+
+        # apply same modification time than remote host
+        os.utime(targetfile, (now, entry['updated']))
+
+        return True
+
+    def local_sync_taglink(self, username, entry, targetfile):
+        now = int(time.time())
+        items = entry['target'].split("/")
+
+        if os.path.lexists(targetfile):
+            os.remove(targetfile)
+
+        # ignoring last modification time and updating anyway
+        os.chdir(f"{self.localdir}/{username}")
+        os.symlink(f"../{items[0]}/.tag-{items[2]}", entry['name'])
+        os.chdir(self.root)
+
+        # apply same modification on the symlink time than remote host
+        os.utime(targetfile, (now, entry['linktime']), follow_symlinks=False)
+
+        return True
+
+    #
+    # sync statistics
+    #
+    def statistics(self):
+        print("[+]")
+        print("[+] remote official repositories configuration:")
+        print("[+] ------------------------------------------")
+        print(f"[+] {self.officials}")
+        print("[+] ------------------------------------------")
+
+        mbsize = self.downloaded / (1024 * 1024)
+        print(f"[+] downloaded: {mbsize:.2f} MB ({self.files} files)")
+
+
+if __name__ == "__main__":
+    if len(sys.argv) < 3:
+        print("")
+        print(f"  Usage: {sys.argv[0]} [remote-host] [local-directory]")
+        print("")
+        print("  Example:")
+        print(f"    {sys.argv[0]} https://hub.grid.tf /tmp/users")
+        print("")
+
+        sys.exit(1)
+
+    host = sys.argv[1]
+    target = sys.argv[2]
+
+    sync = HubFlistSyncer(host, target)
+
+    repositories = sync.remote_repositories()
+    updating = sync.local_sync_repositories(repositories)
+
+    if len(updating) == 0:
+        print("[+] nothing to update")
+
+    for repo in updating:
+        username = repo['name']
 
-            os.chdir(f"{target}/{repo['name']}")
-            os.symlink(f"../{items[0]}/.tag-{items[2]}", entry['name'])
-            os.chdir(root)
+        userdata = sync.remote_repository(username)
+        sync.local_sync_repository(username, userdata, repo['updated'])
 
-print("")
-print(f"[+] official repos: {officials}")
-print(f"[+] downloaded: {download / (1024 * 1024)} MB ({files} files)")
+    sync.statistics()