I have a library that provides precompiled script plugins, and some of them apply other plugins, e.g.

plugins {
  id("io.gitlab.arturbosch.detekt")
}

After updating to 9.0.0, building the library fails with

Plugin [id: 'io.gitlab.arturbosch.detekt'] was not found in any of the following sources:

- Gradle Core Plugins (plugin is not in 'org.gradle' namespace)
- Included Builds (No included builds contain this plugin)
- Plugin Repositories (plugin dependency must include a version number for this source)

Anyone know if this new failure is intentional or a regression?

Honestly I suspect they will say working as expected. either you need to do

implementation/api

so it gets added to the runtime classpath of the consumer. Or your consumer needs to add it to their root project with an

apply false

so that the version gets specified somewhere. I usually just do

implementation

and rarely have a problem from it adding stuff to the classpath. But every now and then issue pop up from things that use newer versions of kotlin than what the given gradle version embeds.

Turns out it was an issue I reported 2.5 years ago that was recently fixed 😆 Won't be released until 9.1.0 though https://github.com/gradle/gradle/issues/23576

We should have 9.1.0 released pretty soon so you don't have to use the workaround for too long.