diff --git a/Dockerfile b/Dockerfile
index 1ff32c2..8599c96 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,8 +1,4 @@
-FROM phusion/passenger-ruby22:latest
-
-RUN apt-get update \
-  && apt-get install -y ruby2.3 ruby2.3-dev \
-  && ruby-switch --set ruby2.3
+FROM phusion/passenger-ruby23:latest
 
 # Use baseimage-docker's init process.
 CMD ["/sbin/my_init"]