Mailcow: Force build, move build directives into docker-compose override file.
diff --git a/images.nix b/images.nix
index 186dcf1..3098ce2 100644
--- a/images.nix
+++ b/images.nix
@@ -56,6 +56,8 @@
     let
       dockerComposeOverrideYaml =
         pkgs.writeTextDir "docker-compose.override.yml" ''
+          version: '2.1'
+
           services:
             mysql-mailcow:
               image: alpine/socat:1.0.3
@@ -66,6 +68,12 @@
                 - mysql-socket-vol-1:/var/run/mysqld/:Z
               restart: always
 
+            netfilter-mailcow:
+              build: ./data/Dockerfiles/netfilter
+
+            watchdog-mailcow:
+              build: ./data/Dockerfiles/watchdog
+
           volumes:
             vmail-vol-1:                {driver: local, driver_opts: {o: bind, type: none, device: "/vol/vmail"}}
             vmail-index-vol-1:          {driver: local, driver_opts: {o: bind, type: none, device: "/vol/vmail-index"}}
@@ -98,6 +106,8 @@
           ${pkgs.docker}/bin/docker kill $(${pkgs.docker}/bin/docker ps -a -q) || :
           ${pkgs.docker}/bin/docker system prune --volumes --force || :
 
+          ${pkgs.docker-compose}/bin/docker-compose -f /mailcow-dockerized/docker-compose.yml -f ${dockerComposeOverrideYaml}/docker-compose.override.yml build
+
           ${pkgs.busybox}/bin/mkdir -p /tmp /run/{mysql,mysql-socket}
           exec ${pkgs.docker-compose}/bin/docker-compose --env-file /mailcow-dockerized/mailcow.conf -f /mailcow-dockerized/docker-compose.yml -f ${dockerComposeOverrideYaml}/docker-compose.override.yml up --remove-orphans
         '';
diff --git a/mailcow/src/mailcow-dockerized/docker-compose.yml b/mailcow/src/mailcow-dockerized/docker-compose.yml
index 40b2617..5362bfc 100644
--- a/mailcow/src/mailcow-dockerized/docker-compose.yml
+++ b/mailcow/src/mailcow-dockerized/docker-compose.yml
@@ -382,7 +382,7 @@
             - acme
 
     netfilter-mailcow:
-      build: ./data/Dockerfiles/netfilter
+      image: mailcow/netfilter:1.38
       stop_grace_period: 30s
       depends_on:
         - dovecot-mailcow
@@ -405,7 +405,9 @@
         - /lib/modules:/lib/modules:ro
 
     watchdog-mailcow:
-      build: ./data/Dockerfiles/watchdog
+      image: mailcow/watchdog:1.86
+      # Debug
+      #command: /watchdog.sh
       dns:
         - ${IPV4_NETWORK:-172.22.1}.254
       volumes: