diff --git a/swh/storage/sql/10-swh-init.sql b/swh/storage/sql/10-swh-init.sql
--- a/swh/storage/sql/10-swh-init.sql
+++ b/swh/storage/sql/10-swh-init.sql
@@ -4,4 +4,24 @@
 create extension if not exists pgcrypto;
 create extension if not exists pg_trgm;
 
-create or replace language plpgsql;
+-- courtesy of  Andreas 'ads' Scherbaum in
+-- https://andreas.scherbaum.la/blog/archives/346-create-language-if-not-exist.html
+create or replace function public.create_plpgsql_language ()
+    returns text
+    as $$
+        create language plpgsql;
+        select 'language plpgsql created'::text;
+    $$
+language 'sql';
+
+select case when
+    (select true::boolean
+       from pg_language
+       where lanname='plpgsql')
+    then
+      (select 'language already installed'::text)
+    else
+      (select public.create_plpgsql_language())
+    end;
+
+drop function public.create_plpgsql_language ();