diff --git a/README.md b/README.md
index 022802c6..d6d86547 100644
--- a/README.md
+++ b/README.md
@@ -62,13 +62,23 @@ runtime):
 
 ```sh
 docker compose -f compose.yaml -f deploy/compose.local-vector.yaml \
-  -f deploy/compose.preprocess.yaml --profile local-vector --profile preprocess \
-  run --rm preprocess-evidence
+  -f deploy/compose.preprocess.yaml -f deploy/compose.preprocess-local-vector.yaml \
+  --profile local-vector --profile preprocess build preprocess-evidence
 docker compose -f compose.yaml -f deploy/compose.local-vector.yaml \
-  -f deploy/compose.preprocess.yaml --profile local-vector --profile preprocess \
-  run --rm preprocess-dwh
+  -f deploy/compose.preprocess.yaml -f deploy/compose.preprocess-local-vector.yaml \
+  --profile local-vector --profile preprocess run --rm preprocess-evidence
+docker compose -f compose.yaml -f deploy/compose.local-vector.yaml \
+  -f deploy/compose.preprocess.yaml -f deploy/compose.preprocess-local-vector.yaml \
+  --profile local-vector --profile preprocess build preprocess-dwh
+docker compose -f compose.yaml -f deploy/compose.local-vector.yaml \
+  -f deploy/compose.preprocess.yaml -f deploy/compose.preprocess-local-vector.yaml \
+  --profile local-vector --profile preprocess run --rm preprocess-dwh
 ```
 
+The local preprocessing override makes each job wait for the vector database health check,
+role reconciliation, and a successful migration. These commands are safe on a clean Compose
+project; no separate database startup or migration command is required.
+
 S3 Evidence uses the optional `tht[s3]` dependency and canonical `s3://bucket/key` provenance.
 AWS endpoints are used when no custom URL is supplied. Every custom endpoint is an explicit egress
 trust-boundary opt-in and uses path-style addressing; private and HTTP endpoints require additional