diff --git a/README.md b/README.md
index e0595d2..b44594f 100644
--- a/README.md
+++ b/README.md
@@ -644,7 +644,7 @@ Tests require the following:
 export OPENAI_API_KEY=sk-your-key-here
 ```
 
-2. **Neo4j**: See the [Local vs CI Testing](#local-vs-ci-testing) section below.
+2. **Neo4j**, and **Docker** for the Postgres tests: See the [Local vs CI Testing](#local-vs-ci-testing) section below.
 
 3. **A JDK between 21 and 25**. The build targets Java 21 bytecode, so the resulting jar
    runs on any JRE 21+, but it builds on anything up to 25 — CI runs the suite on both 21
@@ -687,6 +687,11 @@ export USE_LOCAL_NEO4J=true
 
 Leave `USE_LOCAL_NEO4J` unset (the default). GitHub Actions uses Testcontainers to automatically spin up Neo4j.
 
+#### Postgres tests
+
+The `*PostgresTest` classes rerun the store tests on Postgres. They start Postgres with pgvector in a Testcontainer
+whatever `USE_LOCAL_NEO4J` says, so `./mvnw test` needs Docker even with a local Neo4j.
+
 ### Running Tests
 
 ```bash
diff --git a/src/main/kotlin/com/embabel/guide/stats/GuideStatsService.kt b/src/main/kotlin/com/embabel/guide/stats/GuideStatsService.kt
index 20ffc24..87e4720 100644
--- a/src/main/kotlin/com/embabel/guide/stats/GuideStatsService.kt
+++ b/src/main/kotlin/com/embabel/guide/stats/GuideStatsService.kt
@@ -28,7 +28,7 @@ import java.time.Instant
  * reuses [GuideUserCache]; its TTL is what makes an out-of-band grant/revocation take effect.
  *
  * Totals use single-label fragment counts. The rankings are Drivine grouped reads: one statement
- * each, on every store Drivine supports, Oracle among them.
+ * each, on every store Drivine supports, Oracle and Postgres among them.
  */
 @Service
 class GuideStatsService(