diff --git a/src/stream/commander/api.clj b/src/stream/commander/api.clj
index 7510a0c..bc4ed39 100644
--- a/src/stream/commander/api.clj
+++ b/src/stream/commander/api.clj
@@ -65,6 +65,7 @@
   [update id]
   (condp = (:ActiveState update)
     "failed" {:event :failed
+              :reason (keyword (:SubState update))
               ;; we take the last message because the journal does not
               ;; distinct between message types from the executable
               :error
@@ -75,10 +76,10 @@
                    (:unit-name process)
                    :number 1
                    :executable (:ffmpeg-path (:ffmpeg-config process))))))}
-    "active" {:event :active}
-    "activating" {:event :activating}
-    "deactivating" {:event :deactivating}
-    "inactive" {:event :inactive}
+    "active" {:event :active :reason (keyword (:SubState update))}
+    "activating" {:event :activating :reason (keyword (:SubState update))}
+    "deactivating" {:event :deactivating :reason (keyword (:SubState update))}
+    "inactive" {:event :inactive :reason (keyword (:SubState update))}
     nil))
 
 (defn- put-process-event!
@@ -210,6 +211,11 @@
                :event event :promise prom :timeout timeout}))
     prom))
 
+(defn multi-event-matcher
+  "Matches any of the given events."
+  [& events]
+  #(some #{(:event %1)} [:inactive :failed]))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
                                         ;          Process Management         ;
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
@@ -294,21 +300,37 @@
   (sys/get-service-state! (:unit-name proc)))
 
 (defn start-process!
-  "Starts the service associated to the process `proc` (either id or
-  process object). Returns a promise that resolves to event `:failed`
-  or `:active` or times out after `timeout` ms."
+  "Starts the service associated to the process `proc`. Returns a
+  promise that resolves to event `:failed` or `:active` or times out
+  after `timeout` ms."
   ([proc timeout]
    (let [prom
-         (wait-for! proc :matcher #(some #{(:event %1)} [:active :failed]))]
+         (wait-for! proc :matcher (multi-event-matcher [:active :failed]))]
      (sys/start-service! (:unit-name proc))
      prom))
   ([proc]
    (start-process! proc +default-timeout+)))
 
 (defn stop-process!
-  "Stops the service associated to the process."
-  [proc]
-  (sys/stop-service! (:unit-name proc)))
+  "Stops the service associated to the process `proc`. Returns a promise
+  that resolves to event `:failed` or `:inactive` or times out after
+  `timeout` ms."
+  ([proc timeout]
+   (let [prom
+         (wait-for! proc :matcher (multi-event-matcher [:inactive :failed]))]
+     (sys/stop-service! (:unit-name proc))
+     prom))
+  ([proc]
+   (start-process! proc +default-timeout+)))
+
+(defn restart-process!
+  "Restarts a process `proc` and wait for stop and start to happen
+  within `timeout`."
+  ([proc timeout]
+   @(stop-process! proc timeout)
+   (start-process! proc timeout))
+  ([proc]
+   (restart-process! proc +default-timeout+)))
 
 (defn process-running?
   "Queries wether a process is running."
diff --git a/test/stream/commander_test.clj b/test/stream/commander_test.clj
index 402bad5..7c7d326 100644
--- a/test/stream/commander_test.clj
+++ b/test/stream/commander_test.clj
@@ -211,15 +211,14 @@
           (is (= :timeout @prom1))))
 
       (testing "stopping the process"
-        (let [prom (api/wait-for!
-                    proc
-                    :matcher #(or (= (:event %1) :inactive)
-                                 (= (:event %1) :failed)))]
-          (api/start-process! proc)
-          (api/stop-process! proc)
+        @(api/start-process! proc)
+        (let [prom (api/stop-process! proc)]
           (is (not (= :timeout @prom)))
           (is (not (api/process-running? proc)))))
 
+      (testing "re starting a process"
+        (is (not (= :timeout (:event @(api/restart-process! proc))))))
+
       (testing "enabling the process"
         (api/enable-process! proc)
         (is (api/process-enabled? proc)))