diff --git a/preface.asciidoc b/preface.asciidoc
index 86746458..74d1396b 100644
--- a/preface.asciidoc
+++ b/preface.asciidoc
@@ -277,6 +277,7 @@ The following is a list of notable GitHub contributors:
 * Reproducibility Matters (TheCharlatan)
 * Reuben Thomas (rrthomas)
 * Robert Furse (Rfurse)
+* Roberto Mannai (robermann)
 * Richard Kiss (richardkiss)
 * rszheng
 * Ruben Alexander (hizzvizz)