diff --git a/Project.toml b/Project.toml
index 8fe12854..57919be5 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "PostNewtonian"
 uuid = "377afc40-5642-4616-8613-b7ebca523866"
-authors = ["Michael Boyle <michael.oliver.boyle@gmail.com> and contributors"]
 version = "0.10.9"
+authors = ["Michael Boyle <michael.oliver.boyle@gmail.com> and contributors"]
 
 [deps]
 DataInterpolations = "82cc6244-b520-54b8-b5a6-8a565e85f1d0"
@@ -35,7 +35,7 @@ Aqua = "0.8"
 DataInterpolations = "5.1, 6, 7, 8"
 DoubleFloats = "1.4"
 ExplicitImports = "1.8"
-FastDifferentiation = "0.3.15"
+FastDifferentiation = "0.3.15, 0.4"
 FileIO = "1.16.3"
 ForwardDiff = "0.10.38, 1"
 HDF5 = "0.17.2"