diff --git a/meta/classes/image_types.bbclass b/meta/classes/image_types.bbclass
index f7de756b71..2b97397a51 100644
--- a/meta/classes/image_types.bbclass
+++ b/meta/classes/image_types.bbclass
@@ -218,6 +218,52 @@ USING_WIC = "${@bb.utils.contains_any('IMAGE_FSTYPES', 'wic ' + ' '.join('wic.%s
 WKS_FILE_CHECKSUM = "${@'${WKS_FULL_PATH}:%s' % os.path.exists('${WKS_FULL_PATH}') if '${USING_WIC}' else ''}"
 do_image_wic[file-checksums] += "${WKS_FILE_CHECKSUM}"
 
+python do_write_wks_template () {
+    """Write out expanded template contents to WKS_FULL_PATH."""
+    import re
+
+    template_body = d.getVar('_WKS_TEMPLATE', True)
+
+    # Remove any remnant variable references left behind by the expansion
+    # due to undefined variables
+    expand_var_regexp = re.compile(r"\${[^{}@\n\t :]+}")
+    while True:
+        new_body = re.sub(expand_var_regexp, '', template_body)
+        if new_body == template_body:
+            break
+        else:
+            template_body = new_body
+
+    wks_file = d.getVar('WKS_FULL_PATH', True)
+    with open(wks_file, 'w') as f:
+        f.write(template_body)
+}
+
+python () {
+    if d.getVar('USING_WIC', True):
+        wks_file_u = d.getVar('WKS_FULL_PATH', False)
+        wks_file = d.expand(wks_file_u)
+        base, ext = os.path.splitext(wks_file)
+        if ext == '.in' and os.path.exists(wks_file):
+            wks_out_file = os.path.join(d.getVar('WORKDIR', True), os.path.basename(base))
+            d.setVar('WKS_FULL_PATH', wks_out_file)
+            d.setVar('WKS_TEMPLATE_PATH', wks_file_u)
+            d.setVar('WKS_FILE_CHECKSUM', '${WKS_TEMPLATE_PATH}:True')
+
+            try:
+                with open(wks_file, 'r') as f:
+                    body = f.read()
+            except (IOError, OSError) as exc:
+                pass
+            else:
+                # Previously, I used expandWithRefs to get the dependency list
+                # and add it to WICVARS, but there's no point re-parsing the
+                # file in process_wks_template as well, so just put it in
+                # a variable and let the metadata deal with the deps.
+                d.setVar('_WKS_TEMPLATE', body)
+                bb.build.addtask('do_write_wks_template', 'do_image_wic', None, d)
+}
+
 EXTRA_IMAGECMD = ""
 
 inherit siteinfo