diff --git a/docker/python-builder/scripts/assemble b/docker/python-builder/scripts/assemble
index 83a9ba939d..611ff44f82 100755
--- a/docker/python-builder/scripts/assemble
+++ b/docker/python-builder/scripts/assemble
@@ -27,15 +27,7 @@ cd /tmp/src
 
 apt-get update
 
-# pbr needs git installed, else nothing will work
-apt-get install -y git
-
-# Use a clean virtualenv for install steps to prevent things from the
-# current environment making us not build a wheel.
-python -m venv /tmp/venv
-/tmp/venv/bin/pip install -U pip wheel
-
-function install_pwd {
+function install_bindep {
     # Protect from the bindep builder image use of the assemble script
     # to produce a wheel.  Note we append because we want all
     # sibling packages in here too
@@ -46,7 +38,9 @@ function install_pwd {
             apt-get install -y ${compile_packages}
         fi
     fi
+}
 
+function install_wheels {
     # Build a wheel so that we have an install target.
     # pip install . in the container context with the mounted
     # source dir gets ... exciting.
@@ -79,13 +73,32 @@ function install_pwd {
     done
 }
 
-# Install the main package
-install_pwd
+# bindep the main package
+install_bindep
 
 # go through ZUUL_SIBLINGS, if any, and build those wheels too
 for sibling in ${ZUUL_SIBLINGS:-}; do
     pushd .zuul-siblings/${sibling}
-    install_pwd
+    install_bindep
+    popd
+done
+
+# pbr needs git installed, else nothing will work. Do this in between
+# bindep and wheel so that we don't miss git in target images.
+apt-get install -y git
+
+# Use a clean virtualenv for install steps to prevent things from the
+# current environment making us not build a wheel.
+python -m venv /tmp/venv
+/tmp/venv/bin/pip install -U pip wheel
+
+# Install the main package
+install_wheels
+
+# go through ZUUL_SIBLINGS, if any, and build those wheels too
+for sibling in ${ZUUL_SIBLINGS:-}; do
+    pushd .zuul-siblings/${sibling}
+    install_wheels
     popd
 done