Ubuntu Blog: Java 25 now available on Google Cloud Serverless

(December 11, 2025) Canonical, the publisher of Ubuntu, today announced the immediate availability of Java 25 across Google Cloud’s serverless portfolio, including Cloud Run, App Engine and Cloud Functions.

This release is the result of a collaboration between Google Cloud and Canonical, and it will allow developers to access the latest Java features as soon as they are publicly released. All three serverless products used Ubuntu 24.04 as the base image, with Canonical actively maintaining the runtime and ensuring timely security patches.

Simplified deployment with Buildpacks

Deploying Java 25 is easy and fast thanks to Google Cloud Buildpacks. No need to create manual Dockerfiles or manage complex container configurations.

Buildpacks are designed to automatically convert your source code into a production-ready container image. When you deploy your application, the Buildpacks system detects your requested Java version and automatically provides the Ubuntu-based Java 25 environment, which Canonical team constantly updates with security fixes. This “source-to-deployment” workflow allows you to focus entirely on writing code while Google Cloud and Canonical handle the underlying operating system and runtime security.

Start

To get started, simply use the GOOGLE_RUNTIME_VERSION environment variable to specify the JDK version up to 25.

package build java-app –builder=gcr.io/buildpacks/builder –env GOOGLE_RUNTIME_VERSION=25

To learn more about canonical support on Java, please read our reference documentation.

More reading and resources

• Runtime Support Details
• Ubuntu base images
• Learn more about Buildpacks