diff --git a/README.md b/README.md
index 478cc22e..8c251aec 100644
--- a/README.md
+++ b/README.md
@@ -58,6 +58,17 @@ Set `ADDITIONAL_VALUES_FILES` environment variable to a comma-separated list of
 ADDITIONAL_VALUES_FILES=./my-values.yaml make up
 ```
 
+### PostgreSQL configuration
+
+The `postgresql` value is passed to the PostgreSQL chart. For example, to raise `max_connections` (default 100), put this in a values file and use it via `ADDITIONAL_VALUES_FILES` (or the `additional-values-files` input of the `setup-cf` action):
+
+```yaml
+postgresql:
+  primary:
+    extendedConfiguration: |
+      max_connections = 500
+```
+
 ## Using the `setup-cf` GitHub Action
 
 This repository ships a composite action at `.github/actions/setup-cf` that provisions a full Cloud Foundry environment on a KinD cluster inside a GitHub Actions workflow. After it completes, the generated credentials from `temp/secrets.env` are exported into `$GITHUB_ENV`, so later steps can use the CF CLI directly.
diff --git a/helmfile.yaml.gotmpl b/helmfile.yaml.gotmpl
index a782644c..7ca1545a 100644
--- a/helmfile.yaml.gotmpl
+++ b/helmfile.yaml.gotmpl
@@ -162,6 +162,7 @@ releases:
       - ./assets/values/postgresql.yaml
       - auth:
           password: {{ .Values.secrets.dbPassword }}
+      - {{- toYaml .Values.postgresql | nindent 8 }}
 
   - name: minio
     namespace: {{ .Values.systemNamespace }}
diff --git a/values.yaml.gotmpl b/values.yaml.gotmpl
index 10668259..e9be3b61 100644
--- a/values.yaml.gotmpl
+++ b/values.yaml.gotmpl
@@ -10,6 +10,7 @@ localDeployment: {{ "LOCAL_DEPLOYMENT" | env | default "true" }}
 installOptionalComponents: {{ "INSTALL_OPTIONAL_COMPONENTS" | env | default "true" }}
 gateway:
   infrastructure: {}
+postgresql: {}
 secrets:
   dbPassword: {{ requiredEnv "DB_PASSWORD" }}
   blobstorePassword: {{ requiredEnv "BLOBSTORE_PASSWORD" }}