diff --git a/bot/build.sh b/bot/build.sh
index 2884db8de4..2a560bae0c 100755
--- a/bot/build.sh
+++ b/bot/build.sh
@@ -3,7 +3,7 @@
 # give up as soon as any error occurs
 set -e
 
-git clone https://github.com/EESSI/software-layer-scripts
+git clone -b improve_building_on_top_support https://github.com/SURF-hpcv/software-layer-scripts
 
 # symlink everything, except for:
 # - common files like LICENSE and README.md
diff --git a/easystacks/software.caspar.nl/2025.06/eessi-2025.06-eb-5.3.0-2025b.yml b/easystacks/software.caspar.nl/2025.06/eessi-2025.06-eb-5.3.0-2025b.yml
new file mode 100644
index 0000000000..681775bf28
--- /dev/null
+++ b/easystacks/software.caspar.nl/2025.06/eessi-2025.06-eb-5.3.0-2025b.yml
@@ -0,0 +1,2 @@
+easyconfigs:
+  - Biopython-1.86-gfbf-2025b.eb