Historically, Gradle has shipped with some Groovy types in very prominent APIs.
This required the Kotlin DSL to add special integration to work with Groovy closures.
This has also forced plugins written in languages other than Groovy to use Groovy types for some APIs.

When the Kotlin DSL was introduced, we made an effort to add non-Groovy equivalents for all APIs.

dependencies {
    implementation("gradlebuild:basics")

    implementation(project(":cleanup"))
    implementation(project(":documentation"))
    implementation(project(":integration-testing"))
    implementation(project(":performance-testing"))
    implementation(project(":profiling"))
    implementation(project(":binary-compatibility"))

    implementation("org.codenarc:CodeNarc") {

### Code change guidelines

All code contributions should contain the following:

* Create unit tests using [Spock](https://spockframework.org/spock/docs/2.0/index.html) for new classes or methods that you introduce.
* Create integration tests that exercise a Gradle build for the bug/feature. 
* Annotate tests that correspond to a bug on GitHub (`@Issue("https://github.com/gradle/gradle/issues/2622")`).

A downside of this structure is that it is difficult to do focused work on the Gradle UI.

## Decision

Introduce a "UI" architecture module to the core platform, and move the user interaction services to this new module.

This includes:

- Logging and progress services.
- Problem generation services (aka the "problems API").
- User prompting services.
- Build options infrastructure.