diff --git a/src/storage/storage.service.ts b/src/storage/storage.service.ts
index 497ef34..6d1ee0f 100644
--- a/src/storage/storage.service.ts
+++ b/src/storage/storage.service.ts
@@ -7,8 +7,8 @@ export class StorageService {
   storagesMap = new Map<string, Keyv>();
 
   constructor() {
-    const uri = process.env[`STORAGE_URI`];
-    const ttl = parseInt(process.env[`STORAGE_TTL`] ?? 2592000, 10); // 30 days as default
+    const uri: string = process.env[`STORAGE_URI`];
+    const ttl: number = parseInt(process.env[`STORAGE_TTL`] ?? 2592000, 10); // 30 days as default
     if (!uri) {
       this.logger.warn(
         `STORAGE_URI is undefined, will use non persistant in memory storage`,