diff --git a/charts/sourcegraph/examples/external-object-storage/override.yaml b/charts/sourcegraph/examples/external-object-storage/override.yaml
index 2e6adc483..db79f6398 100644
--- a/charts/sourcegraph/examples/external-object-storage/override.yaml
+++ b/charts/sourcegraph/examples/external-object-storage/override.yaml
@@ -16,6 +16,8 @@ objectStorageEnv: &objectStorageEnv
     value: https://s3.us-east-1.amazonaws.com
   PRECISE_CODE_INTEL_UPLOAD_AWS_REGION:
     value: us-east-1
+
+  # If using access key for authentication
   PRECISE_CODE_INTEL_UPLOAD_AWS_ACCESS_KEY_ID:
     secretKeyRef: # Pre-existing secret, not created by this chart
       name: sourcegraph-s3-credentials
@@ -25,6 +27,11 @@ objectStorageEnv: &objectStorageEnv
       name: sourcegraph-s3-credentials
       key: PRECISE_CODE_INTEL_UPLOAD_AWS_SECRET_ACCESS_KEY
 
+  # If using IRSA for role-based authentication on the Kubernetes service account
+  # Do not set ACCESS_KEY_ID or SECRET_ACCESS_KEY; omitting them triggers fallback to IRSA
+  PRECISE_CODE_INTEL_UPLOAD_AWS_USE_EC2_ROLE_CREDENTIALS:
+    value: "true"
+
 frontend:
   env:
     <<: *objectStorageEnv
@@ -32,3 +39,7 @@ frontend:
 preciseCodeIntel:
   env:
     <<: *objectStorageEnv
+
+syntacticCodeIntel:
+  env:
+    <<: *objectStorageEnv