diff --git a/package_builder/constraints.txt b/package_builder/constraints.txt
index 6a0dc28..c010d29 100644
--- a/package_builder/constraints.txt
+++ b/package_builder/constraints.txt
@@ -1,2 +1,2 @@
-epicscorelibs==7.0.7.99.1.1a3
+epicscorelibs==7.0.7.99.1.1
 numpy<2.0  # Numpy 2 breaks some dependencies (at install time) currently. Review and upgrade when possible.
diff --git a/package_builder/requirements.txt b/package_builder/requirements.txt
index 23bc277..5db2033 100644
--- a/package_builder/requirements.txt
+++ b/package_builder/requirements.txt
@@ -54,6 +54,8 @@ ply
 prompt-toolkit
 protobuf
 psutil
+# for pvxslibs used by p4p
+git+https://github.com/ISISComputingGroup/EPICS-pvxs
 py4j  # Only needed here for script generator
 pyasn1==0.6.0
 pygments