diff --git a/Project.toml b/Project.toml
index fe457235..07e6acac 100644
--- a/Project.toml
+++ b/Project.toml
@@ -42,7 +42,7 @@ LabelledArrays = "0.7, 1.0"
 LogDensityProblems = "0.9, 0.10"
 MacroTools = "0.5"
 Missings = "0.4, 1.0"
-ModelingToolkit = "5.6"
+ModelingToolkit = "5.6, 6"
 Optim = "0.19, 0.20, 0.21, 0.22, 1.0"
 PDMats = "0.9, 0.10, 0.11"
 Parameters = "0.12"