diff --git a/implementations/ruby-json_schemer/Dockerfile b/implementations/ruby-json_schemer/Dockerfile
index 68deda2ef..fb9fee47f 100644
--- a/implementations/ruby-json_schemer/Dockerfile
+++ b/implementations/ruby-json_schemer/Dockerfile
@@ -1,11 +1,11 @@
-FROM ruby:3-alpine as builder
+FROM ruby:4-alpine as builder
 
 # unf_ext wants libc++ to compile itself
 RUN apk add --no-cache g++ make
 COPY Gemfile* *.gemspec .
 RUN bundle install
 
-FROM ruby:3-alpine
+FROM ruby:4-alpine
 WORKDIR /usr/src/app
 COPY --from=builder /usr/local/bundle/ /usr/local/bundle/
 COPY . .