diff --git a/taiga/base/utils/collections.py b/taiga/base/utils/collections.py
new file mode 100644
index 00000000..c5ca3c59
--- /dev/null
+++ b/taiga/base/utils/collections.py
@@ -0,0 +1,80 @@
+# -*- coding: utf-8 -*-
+# Copyright (C) 2014-2016 Andrey Antukh <niwi@niwi.nz>
+# Copyright (C) 2014-2016 Jesús Espino <jespinog@gmail.com>
+# Copyright (C) 2014-2016 David Barragán <bameda@dbarragan.com>
+# Copyright (C) 2014-2016 Alejandro Alonso <alejandro.alonso@kaleidos.net>
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero 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 Affero General Public License for more details.
+#
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+import collections
+
+
+class OrderedSet(collections.MutableSet):
+    # Extract from:
+    #     - https://docs.python.org/3/library/collections.abc.html?highlight=orderedset
+    #     - https://code.activestate.com/recipes/576694/
+    def __init__(self, iterable=None):
+        self.end = end = []
+        end += [None, end, end]         # sentinel node for doubly linked list
+        self.map = {}                   # key --> [key, prev, next]
+        if iterable is not None:
+            self |= iterable
+
+    def __len__(self):
+        return len(self.map)
+
+    def __contains__(self, key):
+        return key in self.map
+
+    def add(self, key):
+        if key not in self.map:
+            end = self.end
+            curr = end[1]
+            curr[2] = end[1] = self.map[key] = [key, curr, end]
+
+    def discard(self, key):
+        if key in self.map:
+            key, prev, next = self.map.pop(key)
+            prev[2] = next
+            next[1] = prev
+
+    def __iter__(self):
+        end = self.end
+        curr = end[2]
+        while curr is not end:
+            yield curr[0]
+            curr = curr[2]
+
+    def __reversed__(self):
+        end = self.end
+        curr = end[1]
+        while curr is not end:
+            yield curr[0]
+            curr = curr[1]
+
+    def pop(self, last=True):
+        if not self:
+            raise KeyError('set is empty')
+        key = self.end[1][0] if last else self.end[2][0]
+        self.discard(key)
+        return key
+
+    def __repr__(self):
+        if not self:
+            return '%s()' % (self.__class__.__name__,)
+        return '%s(%r)' % (self.__class__.__name__, list(self))
+
+    def __eq__(self, other):
+        if isinstance(other, OrderedSet):
+            return len(self) == len(other) and list(self) == list(other)
+        return set(self) == set(other)
diff --git a/taiga/projects/tagging/api.py b/taiga/projects/tagging/api.py
index d93ebe72..c2dbd38a 100644
--- a/taiga/projects/tagging/api.py
+++ b/taiga/projects/tagging/api.py
@@ -18,6 +18,7 @@
 
 from taiga.base import response
 from taiga.base.decorators import detail_route
+from taiga.base.utils.collections import OrderedSet
 
 from . import services
 from . import serializers
@@ -101,11 +102,10 @@ class TaggedResourceMixin:
     def pre_save(self, obj):
         if obj.tags:
             self._pre_save_new_tags_in_project_tagss_colors(obj)
-
         super().pre_save(obj)
 
     def _pre_save_new_tags_in_project_tagss_colors(self, obj):
-        new_obj_tags = set()
+        new_obj_tags = OrderedSet()
         new_tags_colors = {}
 
         for tag in obj.tags: