diff --git a/README.md b/README.md
index 04b56ab91..61f17d205 100644
--- a/README.md
+++ b/README.md
@@ -1 +1,9 @@
+Tracking the evolution of https://github.com/uutils/coreutils when executing the GNU coreutils testsuite.
+
 ![Evolution over time](https://github.com/uutils/coreutils-tracking/blob/main/gnu-results.png?raw=true)
+
+Refreshed once a day by github actions.
+
+Based on:
+* https://github.com/uutils/coreutils/blob/master/util/build-gnu.sh
+* https://github.com/uutils/coreutils/blob/master/util/run-gnu-test.sh