diff --git a/preface.asciidoc b/preface.asciidoc
index b3a962be..18de0d20 100644
--- a/preface.asciidoc
+++ b/preface.asciidoc
@@ -233,6 +233,7 @@ The following is a list of notable GitHub contributors:
 * Jonathan Cross (jonathancross)
 * Jorgeminator
 * Kai Bakker (kaibakker)
+* kollokollo
 * lilianrambu
 * Lucas Betschart (lclc)
 * Magomed Aliev (30mb1)