diff --git a/fly.toml b/fly.toml
index 42b764c..c92277d 100644
--- a/fly.toml
+++ b/fly.toml
@@ -9,7 +9,7 @@ primary_region = 'ams'
 [build]
 
 [env]
-  PORT = 3000
+  PORT = "3000"
 
 [http_service]
   internal_port = 3000