diff --git a/scripts/bigquery_config.py b/scripts/bigquery_config.py
index c74e87b..31685f0 100644
--- a/scripts/bigquery_config.py
+++ b/scripts/bigquery_config.py
@@ -33,6 +33,37 @@ CREDENTIALS_PATH = os.environ.get(
 PROJECT_ID = "food-security-asean-project"
 LOCATION   = "asia-southeast2"
 
+
+# SETUP BIGQUERY CLIENT
+
+def get_bigquery_client() -> bigquery.Client:
+    """
+    Create BigQuery client.
+    Priority:
+        1. GOOGLE_CREDENTIALS_JSON env variable (Coolify/production)
+        2. GOOGLE_APPLICATION_CREDENTIALS file path (lokal/development)
+    """
+    credentials_json = os.environ.get("GOOGLE_CREDENTIALS_JSON")
+
+    if credentials_json:
+        credentials_dict = json.loads(credentials_json)
+        credentials = service_account.Credentials.from_service_account_info(
+            credentials_dict,
+            scopes=["https://www.googleapis.com/auth/cloud-platform"]
+        )
+    else:
+        credentials = service_account.Credentials.from_service_account_file(
+            CREDENTIALS_PATH,
+            scopes=["https://www.googleapis.com/auth/cloud-platform"]
+        )
+
+    return bigquery.Client(
+        credentials=credentials,
+        project=PROJECT_ID,
+        location=LOCATION
+    )
+
+
 # DATASET IDs
 # Bronze = Raw Layer | Silver = Staging Layer | Gold = DW Layer (Kimball)