Some weeks ago, I published a Gradle plugin (purposefully and only) to Maven Central (MC) and could happily use it from there. However, when I wanted to demonstrate that one has to use MC as plugin repository to make use of my plugin and that the traditional plugins.gradle.org will not work, it had magically appeared on plugins.gradle.org as well 😱 😂 . Investigating this I found that plugins.gradle.org is sending an HTPP 303 (see other) and forwards the request to MC. I am happy that this is the case as it makes my publishing process much easier, can anyone confirm this is a permanent feature? Nevertheless, on the website I can still only see an older version. Perhaps it would be nice if I could somehow also make the new version visible in the Gradle plugin repo. Background for my decision is that my plugin requires another (core) module and I wanted to publish both in an atomic way (to MC), as there are more components to come (e.g., a Maven plugin to make use the core module as well).

It is and always was a permanent feature. Actually, Plugin Portal redirected to JCenter for things it does not serve itself, which in turn forwarded to Maven Central for things it does not serve itself directly. Now with the final sunset of JCenter, the Plugin Portal was changed to directly redirect to Maven Central. The problem with only publishing a plugin to Maven Central is exactly that of discoverability. Your plugin will be resolvable through the Plugin Portal, but it will not be found in the search on it, or if you published to it earlier will show old versions which might make your users use those old versions, or not use your plugin at all as it appears to be unmaintained or at least old. If you want the integration to the Gradle Plugin Portal web UI, you need to publish to the Gradle Plugin Portal. But nothing prevents you from doing that and also publishing to Maven Central, there are others doing the same.

Shameless plug for my request to have a metadata-only mode to the portal: https://github.com/gradle/plugin-portal-requests/issues/225