diff --git a/Project.toml b/Project.toml
index 37cf92a..1e9ab2c 100644
--- a/Project.toml
+++ b/Project.toml
@@ -21,7 +21,7 @@ Unfold = "181c99d8-e21b-4ff3-b70b-c233eddec679"
 DataFrames = "1"
 DocStringExtensions = "0.9"
 LinearAlgebra = "1"
-MixedModels = "4"
+MixedModels = "4, 5"
 ProgressMeter = "1"
 Reexport = "1"
 SimpleTraits = "0.9"