diff --git a/.ruby-version b/.ruby-version
index 619b537..fa7adc7 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-3.3.3
+3.3.5
diff --git a/Dockerfile b/Dockerfile
index 1b9528a..0ec4fc6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM ruby:3.3.3-alpine3.18
+FROM ruby:3.3.5-alpine3.18
 
 # for postgres: postgresql-dev
 RUN apk add --no-cache \
diff --git a/Gemfile.lock b/Gemfile.lock
index a502eaa..bca2537 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -378,4 +378,4 @@ DEPENDENCIES
   yard
 
 BUNDLED WITH
-   2.5.11
+   2.5.21