Native image

Helidon supports ahead of time compilation using GraalVM native image.

The following table shows support of native-image in Helidon modules (all module names are prefixed with helidon-). Status:

✅ - native-image is supported and tested

👍 - native-image should work, not part of regular tests (yet)

🔶 - native-image works partially (description provided)

⏳ - native-image does not work (and we are working on it!)

🛑 - native-image does not work (and will not work for now)

This is a work in progress, the list is incomplete

Module	Description	native-image status
webserver	HTTP server	✅
media-jsonp-server	JSON-P suppport	✅
media-jsonb-server	JSON-B suppport	👍
media-jsonb-server	Jackson suppport	👍
config	Configuration	✅
config-yaml	YAML file support	✅
config-object-mapping	Object mapping support	🛑
metrics	Metric support	✅
health	Health check support	✅
health-checks	Health checks (built-in)	✅
tracing	Tracing builder	👍
tracing-zipkin	Zipkin tracing support	👍
tracing-jaeger	Jaeger tracing support	👍
security	Security	👍
security-providers-abac	ABAC provider	👍
security-providers-http-auth	HTTP Basic authentication provider	👍
security-providers-http-sign	HTTP Signatures provider	👍
security-providers-oidc	Open ID Connect provider	👍
org.glassfish.jersey.core:jersey-client	Jersey HTTP Client *1	🔶
org.glassfish.jersey.inject:jersey-hk2	Jersey HK2 *2	🔶
security-integration-jersey-client	Security propagation	👍
tracing-jersey-client	Tracing propagation	👍
microprofile-server	MicroProfile server	⏳

*1: Jersey HTTP Client: Jersey core currently contains a dependency on "rendered image writer" - this depends on Image I/O. As a result, you can build such an image on an environment that supports Image I/O (such as a MacOS or a Linux distribution with X). Unfortunately this is not supported when building a native image within a Docker (as is one option in our quickstart example)

*2: Jersey HK2: This is required for the Jersey client to work. We have seen this working without issues, though there is quite a wide filter to include classes for reflection. This results in long image builds.