diff --git a/.devcontainer/Dockerfile b/.devcontainer/Dockerfile
index a675792..ef08e9c 100644
--- a/.devcontainer/Dockerfile
+++ b/.devcontainer/Dockerfile
@@ -13,6 +13,6 @@ RUN apt-get update && export DEBIAN_FRONTEND=noninteractive \
 ADD requirements.txt /tmp/requirements.txt
 RUN PATH="/omd/sites/cmk/bin:${PATH}" \
     OMD_ROOT="/omd/sites/cmk" \
-    /omd/sites/cmk/bin/pip3 install -r /tmp/requirements.txt
+    /omd/sites/cmk/bin/python3 /omd/sites/cmk/bin/pip3 install -r /tmp/requirements.txt
 
 ENTRYPOINT ["/bin/bash"]
\ No newline at end of file
diff --git a/.devcontainer/build.sh b/.devcontainer/build.sh
index 2701331..f2d4407 100755
--- a/.devcontainer/build.sh
+++ b/.devcontainer/build.sh
@@ -1,6 +1,6 @@
 #!/bin/bash
 
-NAME=$(python -c 'print(eval(open("package").read())["name"])')
+NAME=$(python3 -c 'print(eval(open("package").read())["name"])')
 rm /omd/sites/cmk/var/check_mk/packages/* ||:
 ln -s $WORKSPACE/package /omd/sites/cmk/var/check_mk/packages/$NAME
 
@@ -8,8 +8,8 @@ mkp -v pack $NAME
 
 # Set Outputs for GitHub Workflow steps
 if [ -n "$GITHUB_WORKSPACE" ]; then
-    echo "::set-output name=pkgfile::$(ls *.mkp)"
-    echo "::set-output name=pkgname::${NAME}"
-    VERSION=$(python -c 'print(eval(open("package").read())["version"])')
-    echo "::set-output name=pkgversion::$VERSION"
+    echo "pkgfile=$(ls *.mkp)" >> $GITHUB_OUTPUT
+    echo "pkgname=${NAME}" >> $GITHUB_OUTPUT
+    VERSION=$(python3 -c 'print(eval(open("package").read())["version"])')
+    echo "pkgversion=${VERSION}" >> $GITHUB_OUTPUT
 fi
\ No newline at end of file
diff --git a/.github/workflows/pytest.yml b/.github/workflows/pytest.yml
index 8728de1..8899298 100644
--- a/.github/workflows/pytest.yml
+++ b/.github/workflows/pytest.yml
@@ -23,7 +23,7 @@ jobs:
     - name: Setup links
       run: ./.devcontainer/symlink.sh
     - name: Install pytest
-      run: su -l -c "REQUESTS_CA_BUNDLE=/etc/ssl/certs/ca-certificates.crt pip3 install -r $GITHUB_WORKSPACE/.devcontainer/requirements.txt" cmk
+      run: su -l -c "REQUESTS_CA_BUNDLE=/etc/ssl/certs/ca-certificates.crt /omd/sites/cmk/bin/python3 /omd/sites/cmk/bin/pip3 install -r $GITHUB_WORKSPACE/.devcontainer/requirements.txt" cmk
     - name: Update GITHUB_PATH
       run: echo "/omd/sites/cmk/bin" >> $GITHUB_PATH
     - name: Run pytest