diff --git a/Project.toml b/Project.toml
index 3e0ea39..353be3a 100644
--- a/Project.toml
+++ b/Project.toml
@@ -15,7 +15,7 @@ Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 
 [compat]
 ConstructionBase = "1.0"
-IterTools = "1.3"
+IterTools = "1.2, 1.3"
 LsqFit = "0.8, 0.9, 0.10"
 Polynomials = "0.5.2, 0.6, 0.7"
 Roots = "0.8, 1.0"