Quickstart

Nmcp (New Maven Central Publishing) is a plugin that uses the new Central Portal publisher API to publish existing publications to Maven Central and Snapshots.

Nmcp is compatible with modern Gradle development practices:

• Compatible with Configuration Cache.
• Compatible with Isolated project.
• Compatible with multi-project builds.
• Uses classloader isolation to prevent conflicts with other plugins.
• Uses Gradle 8.8 lifecycle callbacks for easy configuration.

Note

Nmcp does not create publications or apply the maven-publish plugin. This must be done using other means. Nmcp uses existing publications, stages them locally and uploads a zip to the Central Portal publisher API.

For a higher level API use vanniktech/gradle-maven-publish-plugin.

Requirements

Nmcp requires Java 17+, Gradle 8.8+ for the settings plugin and Gradle 8.2+ otherwise.

Configuring the settings plugin

We recommend using the settings plugin to configure all your logic in your settings.gradle[.kts] file. For a lower level API, you may also apply the Nmcp plugins directly in your build.gradle[.kts] files. See the manual configuration page for more details.

Add the com.gradleup.nmcp.settings plugin to your settings.gradle[.kts] file and configure the nmcpAggregation extension:

settings.gradle[.kts]

plugins {
  id("com.gradleup.nmcp.settings").version("1.4.0")
}

nmcpSettings {
  centralPortal {
    username = TODO("Create a token username at https://central.sonatype.com/")
    password = TODO("Create a token password at https://central.sonatype.com/")

    // optional: publish manually from the portal
    publishingType = "USER_MANAGED"

    // optional: configure the name of your publication in the portal UI
    publicationName = "my-publication:$version"

    // optional: increase the validation timeout to 30 minutes
    validationTimeout = java.time.Duration.of(30, ChronoUnit.MINUTES)

    // optional: disable waiting for publishing
    publishingTimeout = java.time.Duration.ZERO

    // optional: send publications serially instead of in parallel (might be slower)
    uploadSnapshotsParallelism.set(1)
  }
}

Call publishAggregationToCentralPortal to publish the aggregation:

./gradlew publishAggregationToCentralPortal
# yay everything is uploaded 🎉
# go to https://central.sonatype.com/ to release if you used USER_MANAGED

Call publishAggregationToCentralPortalSnapshots to publish to the snapshots:

./gradlew publishAggregationToCentralPortalSnapshots
# yay everything is uploaded to "https://central.sonatype.com/repository/maven-snapshots/" 🎉

Under the hood, the com.gradle.nmcp.settings plugin applies the com.gradleup.nmcp plugin to all your projects and com.gradleup.nmcp.aggregation to your root project.

If you’re using Gradle < 8.8, if you have a convention plugin or if you need more control over the aggregation, you may also configure the subplugins manually and get more control.

See the manual configuration page for more details.