diff --git a/docs/Project.toml b/docs/Project.toml
index c9f38ad..82af9d6 100644
--- a/docs/Project.toml
+++ b/docs/Project.toml
@@ -17,3 +17,4 @@ Zygote = "e88e6eb3-aa80-5325-afca-941959d7151f"
 [compat]
 Documenter = "1.3"
 Literate = "2.21.0"
+NLsolve = "4.5.1"