diff --git a/ansible/playbook.yml b/ansible/playbook.yml
index 7938aa7b4..84802e469 100644
--- a/ansible/playbook.yml
+++ b/ansible/playbook.yml
@@ -206,3 +206,9 @@
       shell: |
         sudo -u ubuntu bash -c ". /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh && nix profile remove osquery"
       when: stage2_nix
+
+    - name: nix collect garbage
+      become: yes
+      shell: |
+        sudo -u ubuntu bash -c ". /nix/var/nix/profiles/default/etc/profile.d/nix-daemon.sh && nix-collect-garbage -d"
+      when: stage2_nix
diff --git a/common-nix.vars.pkr.hcl b/common-nix.vars.pkr.hcl
index 9b378b4b7..db1efb0a9 100644
--- a/common-nix.vars.pkr.hcl
+++ b/common-nix.vars.pkr.hcl
@@ -1 +1 @@
-postgres-version = "15.6.1.108"
+postgres-version = "15.6.1.109"