diff --git a/docker/README.md b/docker/README.md
--- a/docker/README.md
+++ b/docker/README.md
@@ -584,6 +584,59 @@
   (swh) ~/swh-environment$ swh scheduler task respawn 1
 ```
 
+## Data persistence for a development setting
+
+The default docker-compose.yml configuration is not geared towards data persistence,
+but application testing.
+
+Volumes defined in associated images are anonymous and may get either unused or removed.
+
+One safe way to make sure these volumes persist is to use named external volumes,
+created beforehand.
+To use vanilla named volumes, fully managed by Docker, create them like this:
+
+```
+for vn in swh-storage-data swh-objstorage-data;
+do
+    docker volume create "${vn}"
+done
+```
+
+We can also create them as named host volumes so that the data itself can be managed
+out of the Docker-reserved zone, like a non-containerized service. It makes easier
+to access data from the host, but may raise permission issues on this shared data.
+
+```
+for vn in swh-storage-data swh-objstorage-data;
+do
+    sudo mkdir "/data/docker/${vn}"
+    docker volume create -d local \
+           --opt type=none --opt o=bind --opt device="/data/docker/${vn}" "${vn}"
+done
+```
+
+Then, the volumes may be defined as follows in a `docker-compose.override.yml`.
+Note that volume definitions are merged with those in `docker-compose.yml` based
+on destination path.
+
+```
+services:
+  swh-storage-db:
+    volumes:
+      - "swh_storage_data:/var/lib/postgresql/data"
+  swh-objstorage:
+    volumes:
+      - "objstorage_data:/srv/softwareheritage/objects"
+
+volumes:
+  swh_storage_data:
+    external: true
+  swh_objstorage_data:
+    external: true
+```
+
+This way, `docker-compose down -v` will not remove those volumes along with the
+anonymous ones, only an explicit `docker volume rm` will.
 
 ## Starting a kafka-powered mirror of the storage