diff --git a/Project.toml b/Project.toml
index e1dc76cb..80ae72ea 100644
--- a/Project.toml
+++ b/Project.toml
@@ -66,7 +66,7 @@ ITensorMPS = "0.3"
 ITensors = "0.7"
 IsApprox = "0.1, 1, 2"
 IterTools = "1.4.0"
-KrylovKit = "0.6, 0.7, 0.8"
+KrylovKit = "0.6, 0.7, 0.8, 0.9"
 MacroTools = "0.5"
 NDTensors = "0.3"
 NamedGraphs = "0.6.0"