diff --git a/Dockerfile b/Dockerfile
index ae752ae..b517797 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM docker.io/library/ruby:3.3-slim
+FROM docker.io/library/ruby:4.0-slim
 WORKDIR /app
 
 RUN apt-get update && \