diff --git a/ci/hlgroups.make b/ci/hlgroups.make
new file mode 100644
index 0000000..65b39a8
--- /dev/null
+++ b/ci/hlgroups.make
@@ -0,0 +1,18 @@
+# vim: ft=make
+SHELL = /bin/bash
+
+# Default target to actually run the comparison:
+.PHONY: check
+.INTERMEDIATE: hlgroups deflinks hlgroups.stripped
+
+check: hlgroups.stripped deflinks
+	diff hlgroups.stripped deflinks
+
+hlgroups:
+	grep '\*hl-' ../runtime/doc/*txt | sed -E -e 's/.*:<?\s*//' -e 's/hl-//g' -e 's/\*//g' -e 's/ /\n/g' | sort > hlgroups
+
+deflinks: ../src/highlight.c
+	grep '"default link'  $< | sed 's/.*default link\s*\(.*\)\s.*/\1/' | sort > deflinks
+
+hlgroups.stripped: hlgroups.ignore hlgroups
+	grep -v -x -F -f hlgroups.ignore hlgroups > hlgroups.stripped