initcpio module, very loosely based on the one from the manjaro branch

src/modules/initcpio/main.py

+#!/usr/bin/env python3
+# encoding: utf-8
+# === This file is part of Calamares - <http://github.com/calamares> ===
+#
+#   Copyright 2014, Philip Müller <philm@manjaro.org>
+#
+#   Calamares is free software: you can redistribute it and/or modify
+#   it under the terms of the GNU General Public License as published by
+#   the Free Software Foundation, either version 3 of the License, or
+#   (at your option) any later version.
+#
+#   Calamares is distributed in the hope that it will be useful,
+#   but WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+#   GNU General Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License
+#   along with Calamares. If not, see <http://www.gnu.org/licenses/>.
+
+import libcalamares
+from libcalamares.utils import check_chroot_call
+
+def run_mkinitcpio():
+    kernel = libcalamares.job.configuration['kernel']
+    check_chroot_call(['mkinitcpio', '-p', kernel])
+
+def run():
+    run_mkinitcpio()
+    return None

src/modules/initcpio/module.conf

+type:       "job"
+name:       "initcpio"
+interface:  "python"
+requires:   []
+script:     "main.py"
+configuration:
+    kernel: linux312