diff --git a/prereq_ci.sh b/prereq_ci.sh
index cac2bf00..da30c397 100755
--- a/prereq_ci.sh
+++ b/prereq_ci.sh
@@ -5,4 +5,4 @@ python -m pip install torch==2.0.1
 python -m pip install dgl==1.1.3+cu118
 python -m pip install dglgo==0.0.2
 python -m pip install pyg_lib==0.3.1 torch_scatter==2.1.2 torch_sparse==0.6.18 torch_geometric==2.4.0 torch_cluster==1.6.3 torch_spline_conv==1.2.2 -f https://data.pyg.org/whl/torch-2.0.0+cpu.html
-python -m pip install ultranest==4.3.2 wurlitzer=3.1.1
+python -m pip install ultranest==4.3.2 wurlitzer==3.1.1