diff --git a/Project.toml b/Project.toml
index 9539d57..14ae6a7 100644
--- a/Project.toml
+++ b/Project.toml
@@ -12,6 +12,7 @@ Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 UnitfulAstro = "6112ee07-acf9-5e0f-b108-d242c714bf9f"
 
 [compat]
+Unitful = "1"
 QuadGK = "2"
 UnitfulAstro = "1"
 Documenter = "1"