diff --git a/Project.toml b/Project.toml
index d593da5..bf02e0a 100644
--- a/Project.toml
+++ b/Project.toml
@@ -28,7 +28,7 @@ DataFrames = "1.2.2"
 FillArrays = "1"
 LabelledArrays = "1.6.5"
 Missings = "1.0.2"
-Optim = "1.4.1"
+Optim = "1.4.1, 2.0"
 PaddedViews = "0.5.10"
 Parameters = "0.12.3"
 Pipe = "1.3"