diff --git a/docs/Project.toml b/docs/Project.toml
index 810b0939..88254aac 100644
--- a/docs/Project.toml
+++ b/docs/Project.toml
@@ -23,7 +23,7 @@ Documenter = "1"
 FillArrays = "1"
 ForwardDiff = "0.10"
 LogDensityProblems = "2.1.1"
-Optimisers = "0.3"
+Optimisers = "0.3, 0.4"
 Plots = "1"
 QuasiMonteCarlo = "0.3"
 ReverseDiff = "1"