diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 52cb1fa..441403c 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,5 +1,5 @@
 ---
-image: s3lph/matemat-ci:20180710-02
+image: s3lph/matemat-ci:20180710-03
 
 stages:
 - test
@@ -10,15 +10,15 @@ test:
   stage: test
   script:
   - pip3 install -r requirements.txt
-  - python3-coverage run --branch -m unittest discover matemat
-  - python3-coverage report -m --include 'matemat/*' --omit '*/test_*.py'
+  - sudo -u matemat python3-coverage run --branch -m unittest discover matemat
+  - sudo -u matemat python3-coverage report -m --include 'matemat/*' --omit '*/test_*.py'
 
 codestyle:
   stage: codestyle
   script:
   - pip3 install -r requirements.txt
-  - pycodestyle matemat
-#  - mypy --ignore-missing-imports --strict -p matemat
+  - sudp -u matemat pycodestyle matemat
+#  - sudp -u matemat mypy --ignore-missing-imports --strict -p matemat
 
 docker_build_push:
   stage: deploy
diff --git a/testing/Dockerfile b/testing/Dockerfile
index 3bf3604..5c0e1b3 100644
--- a/testing/Dockerfile
+++ b/testing/Dockerfile
@@ -1,6 +1,9 @@
 
 FROM debian:buster
 
+RUN useradd -d /home/matemat -m matemat
 RUN apt-get update -qy
-RUN apt-get install -y --no-install-recommends git docker.io python3-dev python3-pip python3-coverage python3-setuptools build-essential
+RUN apt-get install -y --no-install-recommends sudo git docker.io python3-dev python3-pip python3-coverage python3-setuptools build-essential
 RUN pip3 install wheel pycodestyle mypy
+
+WORKDIR /home/matemat