diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 0a14a46950896917fa3f3d12e39f9fa805c8c7fa..2a7bde03bd18484353281a736502090c905bcb50 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,21 +1,19 @@
-image: docker:19.03.1
+image: docker:19.03.12
 
 variables:
   DOCKER_TLS_CERTDIR: "/certs"
-  GIT_SUBMODULE_STRATEGY: recursive
-  IMAGE_TAG: $CI_REGISTRY_IMAGE:$CI_COMMIT_REF_SLUG
+  IMAGE_VER: 3.4.13-passenger-1
 
 services:
-  - docker:19.03.1-dind
+  - docker:19.03.12-dind
 
 before_script:
-  - apk update && apk add git
-  - git submodule sync
-  - git submodule update --init
   - docker login -u $CI_REGISTRY_USER -p $CI_REGISTRY_PASSWORD $CI_REGISTRY
 
 build:
   stage: build
   script:
-    - docker build -t $IMAGE_TAG .
-    - docker push $IMAGE_TAG
+    - docker pull $CI_REGISTRY_IMAGE:latest || true
+    - docker build --cache-from $CI_REGISTRY_IMAGE:latest --tag $CI_REGISTRY_IMAGE:$IMAGE_VER --tag $CI_REGISTRY_IMAGE:latest .
+    - docker push $CI_REGISTRY_IMAGE:$IMAGE_VER
+    - docker push $CI_REGISTRY_IMAGE:latest
diff --git a/.gitmodules b/.gitmodules
index da96b176fdacb8da3fbb9daf84d29480612a38c3..2667ef9d23d09644ba6149a764e505cd80e5d1d2 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -16,3 +16,9 @@
 [submodule "plugins/redmine_zulip"]
 	path = plugins/redmine_zulip
 	url = https://github.com/zulip/zulip-redmine-plugin.git
+[submodule "plugins/sparcline"]
+	path = plugins/sparcline
+	url = https://gitlab.pirati.cz/sperling/redmine-sparkline-plugin.git
+[submodule "plugins/redmine-signals-plugin"]
+	path = plugins/redmine-signals-plugin
+	url = https://gitlab.pirati.cz/sperling/redmine-signals-plugin.git
diff --git a/plugins/redmine-signals-plugin b/plugins/redmine-signals-plugin
new file mode 160000
index 0000000000000000000000000000000000000000..80c200c9d1d9f10dc2d7c88ff30adf8a3c009fd2
--- /dev/null
+++ b/plugins/redmine-signals-plugin
@@ -0,0 +1 @@
+Subproject commit 80c200c9d1d9f10dc2d7c88ff30adf8a3c009fd2
diff --git a/plugins/sparcline b/plugins/sparcline
new file mode 160000
index 0000000000000000000000000000000000000000..bd3d99fb681fd2438224f3a146ef4e3b5e7996f2
--- /dev/null
+++ b/plugins/sparcline
@@ -0,0 +1 @@
+Subproject commit bd3d99fb681fd2438224f3a146ef4e3b5e7996f2