diff --git a/examples/deploy-container.sh b/examples/deploy-container.sh
index e02c09a..9ec0bc1 100755
--- a/examples/deploy-container.sh
+++ b/examples/deploy-container.sh
@@ -87,6 +87,7 @@ read -rd '' src <<EOF || true
   };
 }
 EOF
+. "${BASH_SOURCE[0]%/*}"/../test/lib/extra-container-check-version.sh
 extra-container shell -E "$src" "${runCmd[@]}"
 
 # The container is automatically deleted at exit
diff --git a/test/lib/extra-container-check-version.sh b/test/lib/extra-container-check-version.sh
new file mode 100644
index 0000000..1daf42e
--- /dev/null
+++ b/test/lib/extra-container-check-version.sh
@@ -0,0 +1,13 @@
+containerBin=$(type -P extra-container) || true
+if [[ ! ($containerBin && $(realpath "$containerBin") == *extra-container-0.12*) ]]; then
+    echo
+    echo "Building extra-container. Skip this step by adding extra-container 0.12 to PATH."
+    nix build --out-link /tmp/extra-container "${BASH_SOURCE[0]%/*}"/../..#extra-container
+    # When this script is run as root, e.g. when run in an extra-container shell,
+    # chown the gcroot symlink to the regular (login) user so that the symlink can be
+    # overwritten when this script is run without root.
+    if [[ $EUID == 0 ]]; then
+        chown "$(logname):" --no-dereference /tmp/extra-container
+    fi
+    export PATH="/tmp/extra-container/bin${PATH:+:}$PATH"
+fi
diff --git a/test/lib/make-container.sh b/test/lib/make-container.sh
index ff80cee..80ec599 100755
--- a/test/lib/make-container.sh
+++ b/test/lib/make-container.sh
@@ -71,18 +71,6 @@ while [[ $# -gt 0 ]]; do
     esac
 done
 
-containerBin=$(type -P extra-container) || true
-if [[ ! ($containerBin && $(realpath "$containerBin") == *extra-container-0.12*) ]]; then
-    echo
-    echo "Building extra-container. Skip this step by adding extra-container 0.12 to PATH."
-    nix build --out-link /tmp/extra-container "$scriptDir"/..#extra-container
-    # When this script is run as root, e.g. when run in an extra-container shell,
-    # chown the gcroot symlink to the regular (login) user so that the symlink can be
-    # overwritten when this script is run without root.
-    if [[ $EUID == 0 ]]; then
-        chown "$(logname):" --no-dereference /tmp/extra-container
-    fi
-    export PATH="/tmp/extra-container/bin${PATH:+:}$PATH"
-fi
+. "${BASH_SOURCE[0]%/*}"/extra-container-check-version.sh
 
 exec "$container"/bin/container "$containerCommand" "$@"