ansible: cap Docker BuildKit cache at 3GB after every build

delivery-kid/ansible/playbook.yml

@@ -186,6 +186,13 @@
         state: present
         recreate: "{{ 'always' if (rebuild_images | default(false) | bool) else 'auto' }}"
 
+    # Cap BuildKit cache so repeated --rebuild / build:always deploys don't
+    # accumulate (we hit a 28GB / 337-entry cache on 2026-05-30 that took
+    # the host to 100% disk and killed the next deploy). -f prunes dangling
+    # cache only — active layers stay reusable; --keep-storage caps total.
+    - name: Cap Docker BuildKit cache at 3GB
+      command: docker builder prune -f --keep-storage 3GB
+
     # Wait for IPFS container to be running (not API - that won't work until configured)
     - name: Wait for IPFS container to start
       command: docker inspect -f '{% raw %}{{.State.Running}}{% endraw %}' ipfs

hunter/ansible/roles/build-image/tasks/main.yml

@@ -51,3 +51,9 @@
   command: docker images magenta-arthel:latest --format "{% raw %}{{.Repository}}:{{.Tag}}{% endraw %}"
   register: image_check
   failed_when: "'magenta-arthel:latest' not in image_check.stdout"
+
+# Cap BuildKit cache so repeated rebuilds (especially the periodic base-image
+# bumps) don't accumulate unbounded. -f prunes dangling cache only —
+# active layers stay reusable; --keep-storage caps total at 3GB.
+- name: Cap Docker BuildKit cache at 3GB
+  command: docker builder prune -f --keep-storage 3GB

pickipedia-vps/ansible/roles/docker-wiki/handlers/main.yml

@@ -6,5 +6,5 @@
 
 - name: Rebuild wiki container
   command:
-    cmd: docker compose build --no-cache && docker compose up -d
+    cmd: docker compose build --no-cache && docker compose up -d && docker builder prune -f --keep-storage 3GB
     chdir: /opt/pickipedia-docker

pickipedia-vps/ansible/roles/docker-wiki/tasks/main.yml

@@ -66,6 +66,12 @@
     cmd: docker compose build
     chdir: /opt/pickipedia-docker
 
+# Cap BuildKit cache so repeated deploys don't accumulate unbounded.
+# -f prunes dangling cache only — active layers stay reusable;
+# --keep-storage caps total at 3GB.
+- name: Cap Docker BuildKit cache at 3GB
+  command: docker builder prune -f --keep-storage 3GB
+
 # Now the quick switchover — stop nginx, start container
 - name: Stop and disable nginx (replaced by Docker Apache)
   systemd: