diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 143ec60bc209e6a6a68e5d641978d76eeff869ab..177a535c9844d997353e02207cdec9ec5da12447 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -8,9 +8,9 @@ before_script:
 python_run:
   script:
     - apt update && DEBIAN_FRONTEND=noninteractive apt --no-install-recommends -y install ca-certificates gnupg2 apt-transport-https sed
-    - sed -i 's/deb.debian.org/mirror.cs.uni-duesseldorf.de/g' /etc/apt/sources.list && \
-      sed -i 's/security.debian.org/mirror.cs.uni-duesseldorf.de/g' /etc/apt/sources.list && \
-      sed -i 's/main/main contrib non-free/g' /etc/apt/sources.list
+    - /bin/sed -i 's/deb.debian.org/mirror.cs.uni-duesseldorf.de/g' /etc/apt/sources.list && \
+      /bin/sed -i 's/security.debian.org/mirror.cs.uni-duesseldorf.de/g' /etc/apt/sources.list && \
+      /bin/sed -i 's/main/main contrib non-free/g' /etc/apt/sources.list
     - DEBIAN_FRONTEND=noninteractive apt --no-install-recommends -y install nvidia-cuda-toolkit
     - apt clean && apt autoremove && rm -rf /var/lib/apt/lists/*
     - pip install flair