Postgres 16 → 18 (needs a dump/restore at deploy, see runbook)

.github/workflows/ci.yml

@@ -73,7 +73,7 @@ jobs:
           --health-timeout 3s
           --health-retries 10
       postgres:
-        image: postgres:16-alpine
+        image: postgres:18-alpine
         env:
           POSTGRES_USER: tensies
           POSTGRES_PASSWORD: tensies

docker-compose.design.yml

@@ -49,7 +49,7 @@ services:
       retries: 10
 
   postgres:
-    image: postgres:16-alpine
+    image: postgres:18-alpine
     environment:
       POSTGRES_USER: tensies
       POSTGRES_PASSWORD: tensies

docker-compose.prod.yml

@@ -144,13 +144,17 @@ services:
     restart: unless-stopped
 
   postgres:
-    image: postgres:16.15-alpine@sha256:721873c34ceb9f8d8fc265984940dc982404c105f19ad51be9fdc5970a6080ea
+    image: postgres:18.6-alpine@sha256:77f585114c32fbca283dc835b0596f4e52b51b4c6662d7810b2f4084f60a1873
     environment:
       POSTGRES_USER: tensies
       POSTGRES_PASSWORD: "${POSTGRES_PASSWORD:?set POSTGRES_PASSWORD}"
       POSTGRES_DB: tensies
     volumes:
-      - pg_data:/var/lib/postgresql/data
+      # Postgres 18 images keep PGDATA in a versioned subdirectory
+      # (/var/lib/postgresql/18/docker), so the volume mounts one level up.
+      # pg18_data is a fresh volume: the 16.x cluster in pg_data is left
+      # untouched as the rollback copy (data moved by dump/restore).
+      - pg18_data:/var/lib/postgresql
     healthcheck:
       test: ["CMD-SHELL", "pg_isready -U tensies"]
       interval: 5s
@@ -220,6 +224,7 @@ networks:
     driver: bridge
 
 volumes:
-  pg_data:
+  pg_data:     # Postgres 16 cluster, kept as the rollback copy
+  pg18_data:
   prom_data:
   grafana_data:

docker-compose.yml

@@ -62,13 +62,13 @@ services:
       retries: 10
 
   postgres:
-    image: postgres:16-alpine
+    image: postgres:18-alpine
     environment:
       POSTGRES_USER: tensies
       POSTGRES_PASSWORD: tensies
       POSTGRES_DB: tensies
     volumes:
-      - pg_data:/var/lib/postgresql/data
+      - pg18_data:/var/lib/postgresql
     ports:
       - "5432:5432"
     healthcheck:
@@ -123,6 +123,6 @@ services:
       - postgres
 
 volumes:
-  pg_data:
+  pg18_data:
   prom_data:
   grafana_data: