diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 205a2e3..d9f4baf 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,4 +1,4 @@
-image: sobc/gitlab-ci
+image: git.gfz-potsdam.de:5000/naaice/tug:ci
 
 stages:
     - build
@@ -6,8 +6,6 @@ stages:
     - static_analyze
 
 build_release:
-  before_script:
-    - apt-get update && apt-get install -y libeigen3-dev git
   stage: build
   artifacts:
       paths:
@@ -24,11 +22,11 @@ test:
         - ./build/test/testTug
 
 lint:
-  before_script:
-    - apt-get update && apt-get install -y libeigen3-dev
   stage: static_analyze
+  before_script:
+    - apk add clang-extra-tools
   script:
     - mkdir lint && cd lint
-    - cmake -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_CXX_CLANG_TIDY="clang-tidy;-checks=cppcoreguidelines-*,clang-analyzer-*,performance-*,readability-*, modernize-*" -DTUG_ENABLE_TESTING=OFF ..
+    - cmake -DCMAKE_CXX_COMPILER=clang++ -DCMAKE_CXX_CLANG_TIDY="clang-tidy;-checks=cppcoreguidelines-*,clang-analyzer-*,performance-*, modernize-*" -DTUG_ENABLE_TESTING=OFF ..
     - make tug
   when: manual
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 1096dd3..ed46443 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -1,17 +1,20 @@
-include(FetchContent)
+find_library(DOCTEST_LIB doctest)
 
-FetchContent_Declare(
+if(NOT DOCTEST_LIB)
+  include(FetchContent)
+
+  FetchContent_Declare(
     DocTest
     GIT_REPOSITORY https://github.com/doctest/doctest.git
-    GIT_TAG v2.4.9
-)
+    GIT_TAG v2.4.9)
 
-FetchContent_MakeAvailable(DocTest)
+  FetchContent_MakeAvailable(DocTest)
+endif()
 
 add_executable(testTug setup.cpp testBoundaryCondition.cpp testDiffusion.cpp)
 target_link_libraries(testTug doctest tug)
 
-add_custom_target(check
-    COMMAND $<TARGET_FILE:testTug>
-    DEPENDS testTug
-)
+add_custom_target(
+  check
+  COMMAND $<TARGET_FILE:testTug>
+  DEPENDS testTug)
diff --git a/utils/ci.Dockerfile b/utils/ci.Dockerfile
new file mode 100644
index 0000000..30ddc7a
--- /dev/null
+++ b/utils/ci.Dockerfile
@@ -0,0 +1,4 @@
+FROM alpine
+    MAINTAINER Max Luebke <mluebke@uni-potsdam.de>
+
+RUN apk add --no-cache build-base openmp cmake git eigen-dev