Context

In traditional Debezium usage (especially outside Quarkus), configuration is based on plain key-value properties, very similar to Apache Kafka Connect. A typical configuration looks like this:
 

connector.class=io.debezium.connector.mysql.MySqlConnector
database.hostname=localhost
database.port=3306
database.user=root
database.password=secret

 Quarkus allows users to configure features declaratively using application.properties or application.yaml, with clear prefixes like:

quarkus.datasource.db-kind=postgresql
quarkus.kafka.bootstrap-servers=localhost:9092

This namespacing and structure is the standard way Quarkus users expect to configure anything — from HTTP servers to databases to Kafka consumers.

Decision

We will expose all Debezium engine configuration properties under the quarkus.debezium. prefix.

quarkus.debezium.configuration.offset.storage=org.apache.kafka.connect.storage.MemoryOffsetBackingStore
quarkus.debezium.configuration.database.hostname=localhost
quarkus.debezium.configuration.database.port=5432
quarkus.debezium.configuration.database.user=postgres
quarkus.debezium.configuration.database.password=secret
quarkus.debezium.configuration.snapshot.mode=never

Furthermore we want the possibility to use the configuration taken from Quarkus default datasource https://quarkus.io/guides/datasource. In case there is no override made with Debezium configuration, it's possible to use the Quarkus default datasource configuration.

Consequences

• We need to mirror the existing Debezium config keys under quarkus.debezium.configuration.*. This likely involves some mapping logic or proxying config objects to Debezium's internal structures.
• Since Quarkus favors code over configuration, we may later decide to expose high-value behaviors (e.g., snapshot mode, heartbeat tuning) via annotated configuration classes instead of raw strings.
• Users familiar with Kafka Connect-style Debezium configs may need to adjust to the new namespacing and style — though this is expected to be a low barrier.
• Advanced use cases may still require escape hatches, like passing raw properties via a Map<String, String> — we should evaluate if and how to allow this.

References

Debezium Design Document: https://github.com/debezium/debezium-design-documents/pull/16