diff --git a/Project.toml b/Project.toml
index e4736c38..f30763c6 100644
--- a/Project.toml
+++ b/Project.toml
@@ -25,7 +25,7 @@ CTModelsPlots = "Plots"
 
 [compat]
 Aqua = "0.8"
-CTBase = "0.26"
+CTBase = "0.26, 0.18"
 DocStringExtensions = "0.9"
 JLD2 = "0.6"
 JSON3 = "1"