diff --git a/Project.toml b/Project.toml
index 2c6afd93..b70818ef 100644
--- a/Project.toml
+++ b/Project.toml
@@ -18,6 +18,7 @@ LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 Logging = "56ddb016-857b-54e1-b83d-db4d58db5568"
 LsqFit = "2fda8390-95c7-5789-9bda-21331edee243"
 ModelingToolkit = "961ee093-0014-501f-94e3-6117800e7a78"
+Optim = "429524aa-4258-5aef-a3af-852621145aeb"
 OrdinaryDiffEq = "1dea7af3-3e70-54e6-95c3-0bf5283fa5ed"
 Parameters = "d96e819e-fc66-5662-9728-84c9c7592b0a"
 PreallocationTools = "d236fae5-4411-538c-8e31-a6e3d9e00b46"
@@ -54,6 +55,7 @@ IncompleteLU = "0.2"
 IterTools = "1.3"
 LsqFit = "0.12"
 ModelingToolkit = "8"
+Optim = "<1.9.3, >1.9.3"
 OrdinaryDiffEq = "^6"
 Parameters = "0.12"
 PreallocationTools = "0.4"