diff --git a/.gitignore b/.gitignore
index e09e8dc..7192276 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
 bin/
 *.pyc
+*.charm
 .tox
 .testrepository
 .coverage
diff --git a/build-requirements.txt b/build-requirements.txt
new file mode 100644
index 0000000..b6d2452
--- /dev/null
+++ b/build-requirements.txt
@@ -0,0 +1,7 @@
+# NOTES(lourot):
+# * We don't install charmcraft via pip anymore because it anyway spins up a
+#   container and scp the system's charmcraft snap inside it. So the charmcraft
+#   snap is necessary on the system anyway.
+# * `tox -e build` successfully validated with charmcraft 1.2.1
+
+cffi==1.14.6; python_version < '3.6'  # cffi 1.15.0 drops support for py35.
diff --git a/charmcraft.yaml b/charmcraft.yaml
index ba84f31..1974db4 100644
--- a/charmcraft.yaml
+++ b/charmcraft.yaml
@@ -6,6 +6,7 @@ parts:
     source: .
     prime:
       - actions/*
+      - charmhelpers/*
       - files/*
       - hooks/*
       - lib/*
@@ -13,7 +14,6 @@ parts:
       - actions.yaml
       - config.yaml
       - copyright
-      - hardening.yaml
       - icon.svg
       - LICENSE
       - Makefile
diff --git a/osci.yaml b/osci.yaml
index da6cd31..3a71857 100644
--- a/osci.yaml
+++ b/osci.yaml
@@ -4,3 +4,7 @@
       - charm-unit-jobs-py39
       - charm-xena-functional-jobs
       - charm-yoga-functional-jobs
+    vars:
+      needs_charm_build: true
+      charm_build_name: hacluster
+      build_type: charmcraft
diff --git a/rename.sh b/rename.sh
new file mode 100755
index 0000000..d0c35c9
--- /dev/null
+++ b/rename.sh
@@ -0,0 +1,13 @@
+#!/bin/bash
+charm=$(grep "charm_build_name" osci.yaml | awk '{print $2}')
+echo "renaming ${charm}_*.charm to ${charm}.charm"
+echo -n "pwd: "
+pwd
+ls -al
+echo "Removing bad downloaded charm maybe?"
+if [[ -e "${charm}.charm" ]];
+then
+    rm "${charm}.charm"
+fi
+echo "Renaming charm here."
+mv ${charm}_*.charm ${charm}.charm
diff --git a/requirements.txt b/requirements.txt
index 3cfff8b..ead6e89 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -22,4 +22,3 @@ dnspython<2.0.0; python_version < '3.6'
 dnspython; python_version >= '3.6'
 
 psutil>=1.1.1,<2.0.0
-cffi==1.14.6; python_version < '3.6'  # cffi 1.15.0 drops support for py35.
diff --git a/test-requirements.txt b/test-requirements.txt
index 3299333..0aabe17 100644
--- a/test-requirements.txt
+++ b/test-requirements.txt
@@ -41,5 +41,3 @@ git+https://opendev.org/openstack/tempest.git#egg=tempest;python_version>='3.6'
 tempest<24.0.0;python_version<'3.6'
 
 croniter            # needed for charm-rabbitmq-server unit tests
-pyparsing<3.0.0     # but cffi needs it, so pin here.
-cffi==1.14.6; python_version < '3.6'  # cffi 1.15.0 drops support for py35.
diff --git a/tests/bundles/focal-xena.yaml b/tests/bundles/focal-xena.yaml
index c5e96f9..d1cbad6 100644
--- a/tests/bundles/focal-xena.yaml
+++ b/tests/bundles/focal-xena.yaml
@@ -44,7 +44,7 @@ applications:
     channel: latest/edge
 
   hacluster:
-    charm: ../../../hacluster
+    charm: ../../hacluster.charm
     subordinate-to:
       - keystone
 
diff --git a/tests/bundles/focal-yoga.yaml b/tests/bundles/focal-yoga.yaml
index 8b95788..0b270a1 100644
--- a/tests/bundles/focal-yoga.yaml
+++ b/tests/bundles/focal-yoga.yaml
@@ -44,7 +44,7 @@ applications:
     channel: latest/edge
 
   hacluster:
-    charm: ../../../hacluster
+    charm: ../../hacluster.charm
     subordinate-to:
       - keystone
 
diff --git a/tests/bundles/impish-xena.yaml b/tests/bundles/impish-xena.yaml
index 689eee0..502904c 100644
--- a/tests/bundles/impish-xena.yaml
+++ b/tests/bundles/impish-xena.yaml
@@ -44,7 +44,7 @@ applications:
     channel: latest/edge
 
   hacluster:
-    charm: ../../../hacluster
+    charm: ../../hacluster.charm
     subordinate-to:
       - keystone
 
diff --git a/tests/bundles/jammy-yoga.yaml b/tests/bundles/jammy-yoga.yaml
index ee42519..0130362 100644
--- a/tests/bundles/jammy-yoga.yaml
+++ b/tests/bundles/jammy-yoga.yaml
@@ -44,7 +44,7 @@ applications:
     channel: latest/edge
 
   hacluster:
-    charm: ../../../hacluster
+    charm: ../../hacluster.charm
     subordinate-to:
       - keystone
 
diff --git a/tox.ini b/tox.ini
index 86d1e90..81fd249 100644
--- a/tox.ini
+++ b/tox.ini
@@ -37,10 +37,20 @@ setenv = VIRTUAL_ENV={envdir}
 install_command =
   {toxinidir}/pip.sh install {opts} {packages}
 commands = stestr run --slowest {posargs}
-allowlist_externals = juju
+allowlist_externals =
+    charmcraft
+    rename.sh
 passenv = HOME TERM CS_* OS_* TEST_*
 deps = -r{toxinidir}/test-requirements.txt
 
+[testenv:build]
+basepython = python3
+deps = -r{toxinidir}/build-requirements.txt
+commands =
+    charmcraft clean
+    charmcraft -v build
+    {toxinidir}/rename.sh
+
 [testenv:py35]
 basepython = python3.5
 deps = -r{toxinidir}/requirements.txt