diff --git a/backend/test/app_tests/test_util_objects_map.clj b/backend/test/app_tests/test_util_objects_map.clj
new file mode 100644
index 000000000..24e4b3b08
--- /dev/null
+++ b/backend/test/app_tests/test_util_objects_map.clj
@@ -0,0 +1,150 @@
+;; This Source Code Form is subject to the terms of the Mozilla Public
+;; License, v. 2.0. If a copy of the MPL was not distributed with this
+;; file, You can obtain one at http://mozilla.org/MPL/2.0/.
+;;
+;; Copyright (c) KALEIDOS INC
+
+(ns app-tests.test-util-objects-map
+  (:require
+   [app-tests.test-helpers :as th]
+   [app.common.spec :as us]
+   [app.common.transit :as transit]
+   [app.common.types.shape :as cts]
+   [app.common.uuid :as uuid]
+   [app.util.fressian :as fres]
+   [app.util.objects-map :as omap]
+   [clojure.pprint :refer [pprint]]
+   [clojure.spec.alpha :as s]
+   [clojure.test :as t]
+   [clojure.test.check.clojure-test :refer [defspec]]
+   [clojure.test.check.generators :as gen]
+   [clojure.test.check.properties :as props]))
+
+(t/deftest basic-operations
+  (t/testing "assoc"
+    (let [id  (uuid/custom 0 1)
+          id' (uuid/custom 0 2)
+          obj (-> (omap/create) (assoc id {:foo 1}))]
+      (t/is (not= id id'))
+      (t/is (not (contains? obj id')))
+      (t/is (contains? obj id))))
+
+  (t/testing "dissoc"
+    (let [id  (uuid/custom 0 1)
+          obj (-> (omap/create) (assoc id {:foo 1}))]
+      (t/is (contains? obj id))
+      (let [obj (dissoc obj id)]
+        (t/is (not (contains? obj id))))))
+
+  (t/testing "dissoc"
+    (let [id  (uuid/custom 0 1)
+          obj (-> (omap/create) (assoc id {:foo 1}))]
+      (t/is (contains? obj id))
+      (let [obj (dissoc obj id)]
+        (t/is (not (contains? obj id))))))
+
+  (t/testing "seq"
+    (let [id  (uuid/custom 0 1)
+          obj (-> (omap/create) (assoc id 1))]
+      (t/is (contains? obj id))
+      (let [[entry] (seq obj)]
+        (t/is (map-entry? entry))
+        (t/is (= (key entry) id))
+        (t/is (= (val entry) 1)))))
+
+  (t/testing "const & count"
+    (let [obj (into (omap/create) [[uuid/zero 1]])]
+      (t/is (contains? obj uuid/zero))
+      (t/is (= 1 (count obj)))
+      (t/is (omap/objects-map? obj))))
+
+  (t/testing "wrap"
+    (let [obj1 (omap/wrap {})
+          tmp  (omap/create)
+          obj2 (omap/wrap tmp)]
+      (t/is (omap/objects-map? obj1))
+      (t/is (omap/objects-map? obj2))
+      (t/is (identical? tmp obj2))
+      (t/is (= 0 (count obj1)))
+      (t/is (= 0 (count obj2)))))
+
+  (t/testing "error on non-uuid keys"
+    (let [obj (omap/wrap {})]
+      (t/is (thrown? IllegalArgumentException (assoc obj :foo "bar")))))
+
+  )
+
+(t/deftest internal-operation
+  (t/testing "modified & compact"
+    (let [id1 (uuid/custom 0 1)
+          id2 (uuid/custom 0 2)
+          obj (omap/wrap {id1 1 id2 2})]
+      (t/is (= 2 (count obj)))
+      (t/is (omap/modified? obj))
+      (omap/compact! obj)
+      (t/is (not (omap/modified? obj)))
+      (t/is (bytes? (deref obj)))))
+
+  (t/testing "low-level serialize/deserialize"
+    (let [id1 (uuid/custom 0 1)
+          id2 (uuid/custom 0 2)
+          obj1 (omap/wrap {id1 1 id2 2})
+          obj2 (omap/create (deref obj1))]
+      (t/is (= (get obj1 id1) (get obj2 id1)))
+      (t/is (= (get obj1 id2) (get obj2 id2)))
+      (t/is (= (count obj1) (count obj2)))
+      (t/is (= (hash obj1) (hash obj2)))))
+  )
+
+(defspec internal-encode-decode 25
+  (props/for-all
+   [data (->> (gen/map gen/uuid (s/gen ::cts/shape))
+              (gen/not-empty))]
+   (let [obj1 (omap/wrap data)
+         obj2 (omap/create (deref obj1))
+         obj3 (assoc obj2 uuid/zero 1)
+         obj4 (omap/create (deref obj3))]
+     ;; (app.common.pprint/pprint data)
+     (t/is (= (hash obj1) (hash obj2)))
+     (t/is (not= (hash obj2) (hash obj3)))
+     (t/is (bytes? (deref obj3)))
+     (t/is (pos? (alength (deref obj3))))
+     (t/is (= (hash obj3) (hash obj4))))))
+
+(defspec fressian-encode-decode 25
+  (props/for-all
+   [data (->> (gen/map gen/uuid (s/gen ::cts/shape))
+              (gen/not-empty)
+              (gen/fmap omap/wrap)
+              (gen/fmap (fn [o] {:objects o})))]
+   (let [res (-> data fres/encode fres/decode)]
+     (t/is (contains? res :objects))
+     (t/is (omap/objects-map? (:objects res)))
+     (t/is (= (count (:objects data))
+              (count (:objects res))))
+     (t/is (= (hash (:objects data))
+              (hash (:objects res)))))))
+
+(defspec transit-encode-decode 25
+  (props/for-all
+   [data (->> (gen/map gen/uuid (s/gen ::cts/shape))
+              (gen/not-empty)
+              (gen/fmap omap/wrap)
+              (gen/fmap (fn [o] {:objects o})))]
+   (let [res (-> data transit/encode transit/decode)]
+     ;; (app.common.pprint/pprint data)
+     ;; (app.common.pprint/pprint res)
+     (doseq [[k v] (:objects res)]
+       (t/is (= v (get-in data [:objects k]))))
+
+     (t/is (contains? res :objects))
+     (t/is (contains? data :objects))
+
+     (t/is (omap/objects-map? (:objects data)))
+     (t/is (not (omap/objects-map? (:objects res))))
+
+     (t/is (= (count (:objects data))
+              (count (:objects res)))))))
+
+
+