diff --git a/java/builder.go b/java/builder.go
index 8615664..f1a6ead 100644
--- a/java/builder.go
+++ b/java/builder.go
@@ -60,26 +60,6 @@
 		"javacFlags", "bootClasspath", "classpath", "processorpath", "srcJars", "srcJarDir",
 		"outDir", "annoDir", "javaVersion")
 
-	kotlinc = pctx.AndroidGomaStaticRule("kotlinc",
-		blueprint.RuleParams{
-			Command: `rm -rf "$classesDir" "$srcJarDir" "$kotlinBuildFile" && mkdir -p "$classesDir" "$srcJarDir" && ` +
-				`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
-				`${config.GenKotlinBuildFileCmd} $classpath $classesDir $out.rsp $srcJarDir/list > $kotlinBuildFile &&` +
-				`${config.KotlincCmd} $kotlincFlags ` +
-				`-jvm-target $kotlinJvmTarget -Xbuild-file=$kotlinBuildFile && ` +
-				`${config.SoongZipCmd} -jar -o $out -C $classesDir -D $classesDir`,
-			CommandDeps: []string{
-				"${config.KotlincCmd}",
-				"${config.KotlinCompilerJar}",
-				"${config.GenKotlinBuildFileCmd}",
-				"${config.SoongZipCmd}",
-				"${config.ZipSyncCmd}",
-			},
-			Rspfile:        "$out.rsp",
-			RspfileContent: `$in`,
-		},
-		"kotlincFlags", "classpath", "srcJars", "srcJarDir", "classesDir", "kotlinJvmTarget", "kotlinBuildFile")
-
 	turbine = pctx.AndroidStaticRule("turbine",
 		blueprint.RuleParams{
 			Command: `rm -rf "$outDir" && mkdir -p "$outDir" && ` +
@@ -177,35 +157,6 @@
 	protoRoot        bool
 }
 
-func TransformKotlinToClasses(ctx android.ModuleContext, outputFile android.WritablePath,
-	srcFiles, srcJars android.Paths,
-	flags javaBuilderFlags) {
-
-	inputs := append(android.Paths(nil), srcFiles...)
-
-	var deps android.Paths
-	deps = append(deps, flags.kotlincClasspath...)
-	deps = append(deps, srcJars...)
-
-	ctx.Build(pctx, android.BuildParams{
-		Rule:        kotlinc,
-		Description: "kotlinc",
-		Output:      outputFile,
-		Inputs:      inputs,
-		Implicits:   deps,
-		Args: map[string]string{
-			"classpath":       flags.kotlincClasspath.FormJavaClassPath("-classpath"),
-			"kotlincFlags":    flags.kotlincFlags,
-			"srcJars":         strings.Join(srcJars.Strings(), " "),
-			"classesDir":      android.PathForModuleOut(ctx, "kotlinc", "classes").String(),
-			"srcJarDir":       android.PathForModuleOut(ctx, "kotlinc", "srcJars").String(),
-			"kotlinBuildFile": android.PathForModuleOut(ctx, "kotlinc-build.xml").String(),
-			// http://b/69160377 kotlinc only supports -jvm-target 1.6 and 1.8
-			"kotlinJvmTarget": "1.8",
-		},
-	})
-}
-
 func TransformJavaToClasses(ctx android.ModuleContext, outputFile android.WritablePath, shardIdx int,
 	srcFiles, srcJars android.Paths, flags javaBuilderFlags, deps android.Paths) {
 
diff --git a/java/java.go b/java/java.go
index 7e82c59..d2710a8 100644
--- a/java/java.go
+++ b/java/java.go
@@ -974,7 +974,7 @@
 		flags.kotlincClasspath = append(flags.kotlincClasspath, deps.classpath...)
 
 		kotlinJar := android.PathForModuleOut(ctx, "kotlin", jarName)
-		TransformKotlinToClasses(ctx, kotlinJar, kotlinSrcFiles, srcJars, flags)
+		kotlinCompile(ctx, kotlinJar, kotlinSrcFiles, srcJars, flags)
 		if ctx.Failed() {
 			return
 		}
diff --git a/java/java_test.go b/java/java_test.go
index 6437c0c..e16ae35 100644
--- a/java/java_test.go
+++ b/java/java_test.go
@@ -571,68 +571,6 @@
 	}
 }
 
-func TestKotlin(t *testing.T) {
-	ctx := testJava(t, `
-		java_library {
-			name: "foo",
-			srcs: ["a.java", "b.kt"],
-		}
-
-		java_library {
-			name: "bar",
-			srcs: ["b.kt"],
-			libs: ["foo"],
-			static_libs: ["baz"],
-		}
-
-		java_library {
-			name: "baz",
-			srcs: ["c.java"],
-		}
-		`)
-
-	fooKotlinc := ctx.ModuleForTests("foo", "android_common").Rule("kotlinc")
-	fooJavac := ctx.ModuleForTests("foo", "android_common").Rule("javac")
-	fooJar := ctx.ModuleForTests("foo", "android_common").Output("combined/foo.jar")
-
-	if len(fooKotlinc.Inputs) != 2 || fooKotlinc.Inputs[0].String() != "a.java" ||
-		fooKotlinc.Inputs[1].String() != "b.kt" {
-		t.Errorf(`foo kotlinc inputs %v != ["a.java", "b.kt"]`, fooKotlinc.Inputs)
-	}
-
-	if len(fooJavac.Inputs) != 1 || fooJavac.Inputs[0].String() != "a.java" {
-		t.Errorf(`foo inputs %v != ["a.java"]`, fooJavac.Inputs)
-	}
-
-	if !strings.Contains(fooJavac.Args["classpath"], fooKotlinc.Output.String()) {
-		t.Errorf("foo classpath %v does not contain %q",
-			fooJavac.Args["classpath"], fooKotlinc.Output.String())
-	}
-
-	if !inList(fooKotlinc.Output.String(), fooJar.Inputs.Strings()) {
-		t.Errorf("foo jar inputs %v does not contain %q",
-			fooJar.Inputs.Strings(), fooKotlinc.Output.String())
-	}
-
-	fooHeaderJar := ctx.ModuleForTests("foo", "android_common").Output("turbine-combined/foo.jar")
-	bazHeaderJar := ctx.ModuleForTests("baz", "android_common").Output("turbine-combined/baz.jar")
-	barKotlinc := ctx.ModuleForTests("bar", "android_common").Rule("kotlinc")
-
-	if len(barKotlinc.Inputs) != 1 || barKotlinc.Inputs[0].String() != "b.kt" {
-		t.Errorf(`bar kotlinc inputs %v != ["b.kt"]`, barKotlinc.Inputs)
-	}
-
-	if !inList(fooHeaderJar.Output.String(), barKotlinc.Implicits.Strings()) {
-		t.Errorf(`expected %q in bar implicits %v`,
-			fooHeaderJar.Output.String(), barKotlinc.Implicits.Strings())
-	}
-
-	if !inList(bazHeaderJar.Output.String(), barKotlinc.Implicits.Strings()) {
-		t.Errorf(`expected %q in bar implicits %v`,
-			bazHeaderJar.Output.String(), barKotlinc.Implicits.Strings())
-	}
-}
-
 func TestTurbine(t *testing.T) {
 	ctx := testJava(t, `
 		java_library {
diff --git a/java/kotlin.go b/java/kotlin.go
new file mode 100644
index 0000000..5bc7441
--- /dev/null
+++ b/java/kotlin.go
@@ -0,0 +1,71 @@
+// Copyright 2019 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package java
+
+import (
+	"android/soong/android"
+	"strings"
+
+	"github.com/google/blueprint"
+)
+
+var kotlinc = pctx.AndroidGomaStaticRule("kotlinc",
+	blueprint.RuleParams{
+		Command: `rm -rf "$classesDir" "$srcJarDir" "$kotlinBuildFile" && mkdir -p "$classesDir" "$srcJarDir" && ` +
+			`${config.ZipSyncCmd} -d $srcJarDir -l $srcJarDir/list -f "*.java" $srcJars && ` +
+			`${config.GenKotlinBuildFileCmd} $classpath $classesDir $out.rsp $srcJarDir/list > $kotlinBuildFile &&` +
+			`${config.KotlincCmd} $kotlincFlags ` +
+			`-jvm-target $kotlinJvmTarget -Xbuild-file=$kotlinBuildFile && ` +
+			`${config.SoongZipCmd} -jar -o $out -C $classesDir -D $classesDir`,
+		CommandDeps: []string{
+			"${config.KotlincCmd}",
+			"${config.KotlinCompilerJar}",
+			"${config.GenKotlinBuildFileCmd}",
+			"${config.SoongZipCmd}",
+			"${config.ZipSyncCmd}",
+		},
+		Rspfile:        "$out.rsp",
+		RspfileContent: `$in`,
+	},
+	"kotlincFlags", "classpath", "srcJars", "srcJarDir", "classesDir", "kotlinJvmTarget", "kotlinBuildFile")
+
+func kotlinCompile(ctx android.ModuleContext, outputFile android.WritablePath,
+	srcFiles, srcJars android.Paths,
+	flags javaBuilderFlags) {
+
+	inputs := append(android.Paths(nil), srcFiles...)
+
+	var deps android.Paths
+	deps = append(deps, flags.kotlincClasspath...)
+	deps = append(deps, srcJars...)
+
+	ctx.Build(pctx, android.BuildParams{
+		Rule:        kotlinc,
+		Description: "kotlinc",
+		Output:      outputFile,
+		Inputs:      inputs,
+		Implicits:   deps,
+		Args: map[string]string{
+			"classpath":       flags.kotlincClasspath.FormJavaClassPath("-classpath"),
+			"kotlincFlags":    flags.kotlincFlags,
+			"srcJars":         strings.Join(srcJars.Strings(), " "),
+			"classesDir":      android.PathForModuleOut(ctx, "kotlinc", "classes").String(),
+			"srcJarDir":       android.PathForModuleOut(ctx, "kotlinc", "srcJars").String(),
+			"kotlinBuildFile": android.PathForModuleOut(ctx, "kotlinc-build.xml").String(),
+			// http://b/69160377 kotlinc only supports -jvm-target 1.6 and 1.8
+			"kotlinJvmTarget": "1.8",
+		},
+	})
+}
diff --git a/java/kotlin_test.go b/java/kotlin_test.go
new file mode 100644
index 0000000..08a3085
--- /dev/null
+++ b/java/kotlin_test.go
@@ -0,0 +1,82 @@
+// Copyright 2017 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package java
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestKotlin(t *testing.T) {
+	ctx := testJava(t, `
+		java_library {
+			name: "foo",
+			srcs: ["a.java", "b.kt"],
+		}
+
+		java_library {
+			name: "bar",
+			srcs: ["b.kt"],
+			libs: ["foo"],
+			static_libs: ["baz"],
+		}
+
+		java_library {
+			name: "baz",
+			srcs: ["c.java"],
+		}
+		`)
+
+	fooKotlinc := ctx.ModuleForTests("foo", "android_common").Rule("kotlinc")
+	fooJavac := ctx.ModuleForTests("foo", "android_common").Rule("javac")
+	fooJar := ctx.ModuleForTests("foo", "android_common").Output("combined/foo.jar")
+
+	if len(fooKotlinc.Inputs) != 2 || fooKotlinc.Inputs[0].String() != "a.java" ||
+		fooKotlinc.Inputs[1].String() != "b.kt" {
+		t.Errorf(`foo kotlinc inputs %v != ["a.java", "b.kt"]`, fooKotlinc.Inputs)
+	}
+
+	if len(fooJavac.Inputs) != 1 || fooJavac.Inputs[0].String() != "a.java" {
+		t.Errorf(`foo inputs %v != ["a.java"]`, fooJavac.Inputs)
+	}
+
+	if !strings.Contains(fooJavac.Args["classpath"], fooKotlinc.Output.String()) {
+		t.Errorf("foo classpath %v does not contain %q",
+			fooJavac.Args["classpath"], fooKotlinc.Output.String())
+	}
+
+	if !inList(fooKotlinc.Output.String(), fooJar.Inputs.Strings()) {
+		t.Errorf("foo jar inputs %v does not contain %q",
+			fooJar.Inputs.Strings(), fooKotlinc.Output.String())
+	}
+
+	fooHeaderJar := ctx.ModuleForTests("foo", "android_common").Output("turbine-combined/foo.jar")
+	bazHeaderJar := ctx.ModuleForTests("baz", "android_common").Output("turbine-combined/baz.jar")
+	barKotlinc := ctx.ModuleForTests("bar", "android_common").Rule("kotlinc")
+
+	if len(barKotlinc.Inputs) != 1 || barKotlinc.Inputs[0].String() != "b.kt" {
+		t.Errorf(`bar kotlinc inputs %v != ["b.kt"]`, barKotlinc.Inputs)
+	}
+
+	if !inList(fooHeaderJar.Output.String(), barKotlinc.Implicits.Strings()) {
+		t.Errorf(`expected %q in bar implicits %v`,
+			fooHeaderJar.Output.String(), barKotlinc.Implicits.Strings())
+	}
+
+	if !inList(bazHeaderJar.Output.String(), barKotlinc.Implicits.Strings()) {
+		t.Errorf(`expected %q in bar implicits %v`,
+			bazHeaderJar.Output.String(), barKotlinc.Implicits.Strings())
+	}
+}