diff --git a/backend/src/app/http/session.clj b/backend/src/app/http/session.clj
index d3bc0bd2bd..9bcb459b8d 100644
--- a/backend/src/app/http/session.clj
+++ b/backend/src/app/http/session.clj
@@ -332,16 +332,16 @@
 
 (def ^:private
   sql:delete-expired
-  "delete from http_session
-    where updated_at < now() - ?::interval
+  "DELETE FROM http_session
+    WHERE updated_at < ?::timestamptz
        or (updated_at is null and
-           created_at < now() - ?::interval)")
+           created_at < ?::timestamptz)")
 
 (defn- collect-expired-tasks
   [{:keys [::db/conn ::tasks/max-age]}]
-  (let [interval (db/interval max-age)
-        result   (db/exec-one! conn [sql:delete-expired interval interval])
-        result   (:next.jdbc/update-count result)]
+  (let [threshold (ct/minus (ct/now) max-age)
+        result    (-> (db/exec-one! conn [sql:delete-expired threshold threshold])
+                      (db/get-update-count))]
     (l/debug :task "gc"
              :hint "clean http sessions"
              :deleted result)
@@ -350,4 +350,5 @@
 (defmethod ig/init-key ::tasks/gc
   [_ {:keys [::tasks/max-age] :as cfg}]
   (l/debug :hint "initializing session gc task" :max-age max-age)
-  (fn [_] (db/tx-run! cfg collect-expired-tasks)))
+  (fn [_]
+    (db/tx-run! cfg collect-expired-tasks)))
diff --git a/backend/src/app/main.clj b/backend/src/app/main.clj
index 64150b42b1..d6f4cfc4f5 100644
--- a/backend/src/app/main.clj
+++ b/backend/src/app/main.clj
@@ -334,7 +334,7 @@
    :app.rpc.doc/routes
    {:app.rpc/methods (ig/ref :app.rpc/methods)}
 
-   :app.rpc/routes
+   ::rpc/routes
    {::rpc/methods     (ig/ref :app.rpc/methods)
     ::db/pool         (ig/ref ::db/pool)
     ::session/manager (ig/ref ::session/manager)
@@ -426,6 +426,9 @@
     ;; module requires the migrations to run before initialize.
     ::migrations (ig/ref :app.migrations/migrations)}
 
+   ::setup/clock
+   {}
+
    :app.loggers.audit.archive-task/handler
    {::setup/props        (ig/ref ::setup/props)
     ::db/pool            (ig/ref ::db/pool)
diff --git a/backend/src/app/setup/clock.clj b/backend/src/app/setup/clock.clj
new file mode 100644
index 0000000000..09ab991856
--- /dev/null
+++ b/backend/src/app/setup/clock.clj
@@ -0,0 +1,48 @@
+;; 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.setup.clock
+  "A service/module that manages the system clock and allows runtime
+  modification of time offset (useful for testing and time adjustments)."
+  (:require
+   [app.common.logging :as l]
+   [app.common.time :as ct]
+   [app.setup :as-alias setup]
+   [integrant.core :as ig])
+  (:import
+   java.time.Clock
+   java.time.Duration))
+
+(defonce current
+  (atom {:clock (Clock/systemDefaultZone)
+         :offset nil}))
+
+(defmethod ig/init-key ::setup/clock
+  [_ _]
+  (add-watch current ::common
+             (fn [_ _ _ {:keys [clock offset]}]
+               (let [clock (if (ct/duration? offset)
+                             (Clock/offset ^Clock clock
+                                           ^Duration offset)
+                             clock)]
+                 (l/wrn :hint "altering clock" :clock (str clock))
+                 (alter-var-root #'ct/*clock* (constantly clock))))))
+
+
+(defmethod ig/halt-key! ::setup/clock
+  [_ _]
+  (remove-watch current ::common))
+
+(defn set-offset!
+  [duration]
+  (swap! current assoc :offset (some-> duration ct/duration)))
+
+(defn set-clock!
+  ([]
+   (swap! current assoc :clock (Clock/systemDefaultZone)))
+  ([clock]
+   (when (instance? Clock clock)
+     (swap! current assoc :clock clock))))
diff --git a/common/src/app/common/time.cljc b/common/src/app/common/time.cljc
index 3fe0350bd0..c4489f1a88 100644
--- a/common/src/app/common/time.cljc
+++ b/common/src/app/common/time.cljc
@@ -52,6 +52,7 @@
    [cuerdas.core :as str])
   #?(:clj
      (:import
+      java.time.Clock
       java.time.Duration
       java.time.Instant
       java.time.OffsetDateTime
@@ -63,10 +64,15 @@
       java.time.temporal.TemporalAmount
       java.time.temporal.TemporalUnit)))
 
+#?(:clj (def ^:dynamic *clock* (Clock/systemDefaultZone)))
+
 (defn now
-  []
-  #?(:clj (Instant/now)
-     :cljs (new js/Date)))
+  ([]
+   #?(:clj (Instant/now *clock*)
+      :cljs (new js/Date)))
+  ([clock]
+   #?(:cljs (throw (js/Error. "not implemented" {:clock clock}))
+      :clj (Instant/now ^Clock clock))))
 
 ;; --- DURATION
 
@@ -319,12 +325,16 @@
                 :cljs (js/Error. "unsupported type"))))))
 
 (defn in-future
-  [v]
-  (plus (now) v))
+  ([v]
+   (plus (now) v))
+  ([clock v]
+   (plus (now clock) v)))
 
 (defn in-past
-  [v]
-  (minus (now) v))
+  ([v]
+   (minus (now) v))
+  ([clock v]
+   (minus (now clock) v)))
 
 #?(:clj
    (defn diff