diff --git a/resources/db/v2.sql b/resources/db/v2.sql
index ac40b88..f3ee618 100644
--- a/resources/db/v2.sql
+++ b/resources/db/v2.sql
@@ -35,7 +35,6 @@ UPDATE tags
  WHERE t_team = :team
    AND t_artifact = :artifact
    AND t_name = :name
-   AND t_image_id != :image
    AND t_manifest != :manifest;
 
 -- name: get-manifest
diff --git a/test/org/zalando/stups/pierone/v2_test.clj b/test/org/zalando/stups/pierone/v2_test.clj
index e80221e..8b125c2 100644
--- a/test/org/zalando/stups/pierone/v2_test.clj
+++ b/test/org/zalando/stups/pierone/v2_test.clj
@@ -19,7 +19,10 @@
         digest "sha256:a5c741c7dea3a96944022b4b9a0b1480cfbeef5f4cc934850e8afacb48e18c5e"
         invalid-manifest (.getBytes "stuff")
         manifest (str "{\"fsLayers\":[{\"blobSum\":\"" digest "\"}]}")
-        manifest-bytes (.getBytes manifest)]
+        manifest-bytes (.getBytes manifest)
+        ; manifest2 is simply a different manifest (we use the same FS layer twice, does not make sense, but works)
+        manifest2 (str "{\"fsLayers\":[{\"blobSum\":\"" digest "\"},{\"blobSum\":\"" digest "\"}]}")
+        manifest2-bytes (.getBytes manifest2)]
 
     (u/wipe-db system)
 
@@ -95,5 +98,30 @@
             (client/get (u/v1-url "/images/" digest "/json")
                         (u/http-opts)))
 
+    ; check that *-SNAPSHOT tags are mutable
+    (expect 200
+            (client/put (u/v2-url "/myteam/myart/manifests/1.0-SNAPSHOT")
+                        (u/http-opts (io/input-stream manifest-bytes))))
+
+    ; works, no changes
+    (expect 200
+            (client/put (u/v2-url "/myteam/myart/manifests/1.0-SNAPSHOT")
+                        (u/http-opts (io/input-stream manifest-bytes))))
+
+    (is (= manifest
+           (expect 200
+            (client/get (u/v2-url "/myteam/myart/manifests/1.0-SNAPSHOT")
+                        (u/http-opts)))))
+
+    ; update, new manifest
+    (expect 200
+            (client/put (u/v2-url "/myteam/myart/manifests/1.0-SNAPSHOT")
+                        (u/http-opts (io/input-stream manifest2-bytes))))
+
+    (is (= manifest2
+           (expect 200
+            (client/get (u/v2-url "/myteam/myart/manifests/1.0-SNAPSHOT")
+                        (u/http-opts)))))
+
     ; stop
     (component/stop system)))