diff --git a/pubspec.yaml b/pubspec.yaml
index cbd2a1d..f2195d9 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -8,7 +8,7 @@ environment:
 
 dependencies:
   quiver: ^3.0.0
-  petitparser: ">=5.0.0 <7.0.0"
+  petitparser: '>=5.0.0 <8.0.0'
   rxdart: '>=0.27.0 <0.29.0'
   meta: ^1.3.0