diff --git a/test/Project.toml b/test/Project.toml
index 293a740..0a077b1 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -13,3 +13,6 @@ Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 SafeTestsets = "1bc83da4-3b8d-516f-aca4-4fe02f6d838f"
 StatsBase = "2913bbd2-ae8a-5f71-8c99-4fb6c76f3a91"
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
+
+[compat]
+ForwardDiff = "1.4.1"