diff --git a/Dockerfile b/Dockerfile
index 9ee9e4b..4b46895 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:3.3.0-alpine
+FROM ruby:3.3.0-alpine3.18
 
 # for postgres: postgresql-dev
 RUN apk add --no-cache \