Q:

Which configuration properties are not changeable in deployment time / runtime in Quarkus?

I was reading the Quarkus documentation about configuration, and this caught my attention:

Quarkus does much of its configuration and bootstrap at build time. Most properties will then be read and set during the build time step. To change them, make sure to repackage your application.

Where can I find the list of configurations that are not changeable on deployment time/runtime?

A:

All of the Quarkus configuration options can be found here:
https://quarkus.io/guides/all-config
To the left of some properties there is a "lock" icon, which means the configuration property is fixed at build time. All other properties that do not have the "lock" icon next to them may be overridden at runtime.
For example, the quarkus.datasource.jdbc.driver property is fixed at build time, meaning between dev/test/prod you must use the same JDBC driver.  On the other hand, properties such as quarkus.datasource.jdbc.url may be overridden at runtime, so at dev/test time it could point to jdbc://localhost:5432/myDB and in production this value could point to the production DB URL.

