diff --git a/Project.toml b/Project.toml
index fdceeef..c282390 100644
--- a/Project.toml
+++ b/Project.toml
@@ -11,6 +11,7 @@ ParameterizedFunctions = "65888b18-ceab-5e60-b2b9-181511a3b968"
 Sundials = "c3572dad-4567-51f8-b174-8c6c989267f4"
 
 [compat]
+ParameterizedFunctions = "5.6"
 julia = "1"
 
 [extras]