diff --git a/docker-compose.yml b/docker-compose.yml
index 3db8108..15d2bad 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -25,7 +25,10 @@ services:
     ports:
       - "5432:5432"
     volumes:
-      - pgdata:/var/lib/postgresql/data
+      # postgres:18+ requires the volume at /var/lib/postgresql (not /var/lib/postgresql/data)
+      # so PGDATA can live in a major-version-specific subdirectory alongside config.
+      # See https://github.com/docker-library/postgres/pull/1259.
+      - pgdata:/var/lib/postgresql
     healthcheck:
       test: ["CMD-SHELL", "pg_isready -U plugwerk"]
       interval: 5s