diff --git a/Project.toml b/Project.toml
index 059501b..7472b01 100644
--- a/Project.toml
+++ b/Project.toml
@@ -15,6 +15,7 @@ QuadGK = "1fd47b50-473d-5c70-9696-f719f8f3bcdc"
 StatsFuns = "4c63d2b9-4356-54db-8cca-17b64c39e42c"
 
 [compat]
+MixedModels = "4"
 julia = "1"
 
 [extras]