Customize Quarkus for

Now that your code contains all of the configuration to deploy on, it’s time to make your Quarkus site itself ready to run on a environment. There are a number of additional steps that are either required or recommended, depending on how well you want to optimize your site.

Install the Config Reader provides all information about the running environment, including how to connect to services, through environment variables. These may be accessed directly, but it’s often easier to use the Config Reader library. It’s a set of utilities to wrap the environment variables and make them a bit more ergonomic to work with.

Below is an example of how to install the Config Reader for Java using Maven:


and Gradle:

compile group: 'sh.platform', name: 'config', version: '2.2.2'


The file on the previous page has been pulled directly from the Quarkus template. It is sufficient to deploy Quarkus on it’s own, but since Eclipse MicroProfile makes it possible to overwrite configurations without impacting the application itself, you might elect to rely more heavily on environment variables in it’s place.

Consider this simplified file:

name: app

type: "java:11"

disk: 1024

    build: ./mvnw package -DskipTests -Dquarkus.package.uber-jar=true
        start: java -jar $JAVA_OPTS $CREDENTIAL -Dquarkus.http.port=$PORT target/file.jar

On, we can set the environment variable JAVA_OPTS by committing a .environment file to the repository’s root. runs source .environment in the application root when a project starts, and when logging into the environment over SSH. That gives you a place to do extra environment variable setup before the application runs, including modifying the system $PATH and other shell level customizations. It allows us to define JAVA_OPTS when running on, but otherwise not be used during local development testing.

# .environment
export JAVA_OPTS="-Xmx$(jq .info.limits.memory /run/config.json)m -XX:+ExitOnOutOfMemoryError"