Could not find com.android.tools.build:gradle:3.0.0-alpha1 in circle ci

Google have new maven repo

https://android-developers.googleblog.com/2017/10/android-studio-30.html > section Google's Maven Repository

https://developer.android.com/studio/preview/features/new-android-plugin-migration.html https://developer.android.com/studio/build/dependencies.html#google-maven

So add the dependency on maven repo:

buildscript {
    repositories {
        ...
        // You need to add the following repository to download the
        // new plugin.
        google() // new which replace https://maven.google.com
        jcenter()
    }

    dependencies {
        classpath 'com.android.tools.build:gradle:3.6.3'  //Minimum supported Gradle version is 4.6.
    }
}

For things to compile via command line I needed to include the maven repo in BOTH buildscript and allprojects.

root build.gradle:

buildscript {
    repositories {
        jcenter()
        maven { url 'https://maven.google.com' }
    }
    dependencies {
        classpath 'com.android.tools.build:gradle:3.0.0-alpha2'
        ...
    }
}

allprojects {
    repositories {
        jcenter()
        maven { url 'https://maven.google.com' }
    }
}

It's needed in the buildscript block to find the AGP, and in allprojects block to find android.arch and com.android.databinding packages (and others)

UPDATE: It looks like the new repo is just called google() but I still needed to declare it in both places.

To synchronize all of the answers here and elsewhere:

buildscript {
  repositories {
    google() 
    jcenter()
  }
  dependencies {
    classpath 'com.android.tools.build:gradle:3.0.0'

  } }

Make your buildscript in build.gradle look like this. It finds all of them between google and jcenter. Only one of them will not find all of the dependencies as of this answer.