Scala Native compilation mode (nativeMode) via command line

Scala Native has two linking modes:

• debug (default) favours quicker compilation time to runtime, which is great for iterative development;
• release is slower at compile time, but optimises for best runtime performance.

It can just be set in build.sbt file the usual way:

nativeMode := "release"

Ideally I would not like to always use the same mode, but to keep using “debug” on local dev environment and override to “release” on CI build.

Unfortunately I didn’t find a way to achieve it without a boilerplate.

Thankfully it’s not complicated task.

Example below sets “debug” as default and allows to override it via java props, when necessary.

Allow to override default compilation mode in build.sbt via props:

nativeMode := Option(System.getProperty("nativeMode")).getOrElse("debug")

Override default at compilation in CI:

$ sbt -DnativeMode="release" compile

Use default on dev:

$ sbt compile