diff --git a/roles/jenkins/slave/tasks/main.yml b/roles/jenkins/slave/tasks/main.yml
index fcf909a15f..e2c1225f5d 100644
--- a/roles/jenkins/slave/tasks/main.yml
+++ b/roles/jenkins/slave/tasks/main.yml
@@ -1,6 +1,6 @@
 - name: install common slave packages (dnf)
   dnf: name={{ item }} state=installed
-  with_items: {{ slave_packages_common }}
+  with_items: "{{ slave_packages_common }}"
   when: ansible_distribution_major_version|int > 21
   tags:
   - jenkins
@@ -9,7 +9,7 @@
 
 - name: install common slave packages (yum)
   yum: name={{ item }} state=installed
-  with_items: {{ slave_packages_common }}
+  with_items: "{{ slave_packages_common }}"
   when: ansible_distribution_major_version|int < 22
   tags:
   - jenkins
@@ -18,7 +18,7 @@
 
 - name: install distro-specific slave packages (fedora, dnf)
   dnf: name={{ item }} state=installed
-  with_items: {{ slave_packages_fedora }}
+  with_items: "{{ slave_packages_fedora }}"
   when: is_fedora is defined and ansible_distribution_major_version|int > 21
   tags:
   - jenkins
@@ -27,7 +27,7 @@
 
 - name: install distro-specific slave packages (fedora, yum)
   yum: name={{ item }} state=installed
-  with_items: {{ slave_packages_fedora }}
+  with_items: "{{ slave_packages_fedora }}"
   when: is_fedora is defined and ansible_distribution_major_version|int < 22
   tags:
   - jenkins
@@ -36,7 +36,7 @@
 
 - name: install distro-specific slave packages (centos, yum)
   yum: name={{ item }} state=installed
-  with_items: {{ slave_packages_centos }}
+  with_items: "{{ slave_packages_centos }}"
   when: is_fedora is not defined
   tags:
   - jenkins