diff --git a/docs/contributing/4.-acknowledgements.md b/docs/contributing/4.-acknowledgements.md
index 2a6973814..9116be8a8 100644
--- a/docs/contributing/4.-acknowledgements.md
+++ b/docs/contributing/4.-acknowledgements.md
@@ -95,7 +95,7 @@ Code Contributors
 - Anders Kaseorg (@andersk)
 - @r-richmond
 - Sebastian (@sebix)
-
+- Kosei Kitahara (@Surgo)
 
 
 Documenters
@@ -115,6 +115,7 @@ Documenters
 - Taneli Hukkinen (@hukkinj1)
 - @r-richmond
 - John Villalovos (@JohnVillalovos)
+- Kosei Kitahara (@Surgo)
 
 
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