diff --git a/03_source/cms_backend/src/constants.ts b/03_source/cms_backend/src/constants.ts
index 960876f..4a2528f 100644
--- a/03_source/cms_backend/src/constants.ts
+++ b/03_source/cms_backend/src/constants.ts
@@ -1,7 +1,9 @@
+const isDev = process.env.NODE_ENV === 'development';
+
 const L_ERROR = 0;
 const L_WARN = 1;
 const L_INFO = 2;
 const L_DEBUG = 3;
 const L_TRACE = 4;
 
-export { L_WARN, L_INFO, L_ERROR, L_DEBUG, L_TRACE };
+export { L_WARN, L_INFO, L_ERROR, L_DEBUG, L_TRACE, isDev };