diff --git a/java/androidmk.go b/java/androidmk.go
index 24fe43a..64ef505 100644
--- a/java/androidmk.go
+++ b/java/androidmk.go
@@ -165,6 +165,9 @@
 				if app.jacocoReportClassesFile != nil {
 					fmt.Fprintln(w, "LOCAL_SOONG_JACOCO_REPORT_CLASSES_JAR :=", app.jacocoReportClassesFile.String())
 				}
+				if app.proguardDictionary != nil {
+					fmt.Fprintln(w, "LOCAL_SOONG_PROGUARD_DICT :=", app.proguardDictionary.String())
+				}
 
 				if app.Name() == "framework-res" {
 					fmt.Fprintln(w, "LOCAL_MODULE_PATH := $(TARGET_OUT_JAVA_LIBRARIES)")
diff --git a/java/app.go b/java/app.go
index df53375..234dcb7 100644
--- a/java/app.go
+++ b/java/app.go
@@ -125,14 +125,13 @@
 	// apps manifests are handled by aapt, don't let Module see them
 	a.properties.Manifest = nil
 
-	//if !ctx.ContainsProperty("proguard.enabled") {
-	//	a.properties.Proguard.Enabled = true
-	//}
-
 	if String(a.appProperties.Instrumentation_for) == "" {
 		a.properties.Instrument = true
 	}
 
+	a.Module.extraProguardFlagFiles = append(a.Module.extraProguardFlagFiles,
+		proguardOptionsFile)
+
 	if ctx.ModuleName() != "framework-res" {
 		a.Module.compile(ctx, a.aaptSrcJar)
 	}
@@ -324,6 +323,9 @@
 func AndroidAppFactory() android.Module {
 	module := &AndroidApp{}
 
+	module.Module.deviceProperties.Optimize.Enabled = proptools.BoolPtr(true)
+	module.Module.deviceProperties.Optimize.Shrink = proptools.BoolPtr(true)
+
 	module.AddProperties(
 		&module.Module.properties,
 		&module.Module.deviceProperties,
diff --git a/java/builder.go b/java/builder.go
index dae655d..bf826e1 100644
--- a/java/builder.go
+++ b/java/builder.go
@@ -149,7 +149,6 @@
 
 type javaBuilderFlags struct {
 	javacFlags    string
-	dxFlags       string
 	bootClasspath classpath
 	classpath     classpath
 	systemModules classpath
diff --git a/java/config/config.go b/java/config/config.go
index 930e65e..75176c9 100644
--- a/java/config/config.go
+++ b/java/config/config.go
@@ -106,8 +106,8 @@
 			return path.String(), nil
 		}
 	})
-
 	pctx.HostBinToolVariable("D8Cmd", "d8")
+	pctx.HostBinToolVariable("R8Cmd", "r8-compat-proguard")
 
 	pctx.VariableFunc("TurbineJar", func(config android.Config) (string, error) {
 		turbine := "turbine.jar"
diff --git a/java/config/makevars.go b/java/config/makevars.go
index c382cc1..7e125d5 100644
--- a/java/config/makevars.go
+++ b/java/config/makevars.go
@@ -55,6 +55,7 @@
 		ctx.Strict("DX_COMMAND", "${DxCmd} -JXms16M -JXmx2048M")
 		ctx.Strict("USE_D8_DESUGAR", "false")
 	}
+	ctx.Strict("R8_COMPAT_PROGUARD", "${R8Cmd}")
 
 	ctx.Strict("TURBINE", "${TurbineJar}")
 
diff --git a/java/dex.go b/java/dex.go
index fa5c2ee..2beb2ac 100644
--- a/java/dex.go
+++ b/java/dex.go
@@ -108,6 +108,23 @@
 	},
 	"outDir", "dxFlags")
 
+var r8 = pctx.AndroidStaticRule("r8",
+	blueprint.RuleParams{
+		Command: `rm -rf "$outDir" && mkdir -p "$outDir" && ` +
+			`${config.R8Cmd} -injars $in --output $outDir ` +
+			`--force-proguard-compatibility ` +
+			`-printmapping $outDict ` +
+			`$dxFlags $r8Flags && ` +
+			`${config.SoongZipCmd} -o $outDir/classes.dex.jar -C $outDir -D $outDir && ` +
+			`${config.MergeZipsCmd} -D -stripFile "*.class" $out $outDir/classes.dex.jar $in`,
+		CommandDeps: []string{
+			"${config.R8Cmd}",
+			"${config.SoongZipCmd}",
+			"${config.MergeZipsCmd}",
+		},
+	},
+	"outDir", "outDict", "dxFlags", "r8Flags")
+
 func (j *Module) dxFlags(ctx android.ModuleContext, fullD8 bool) []string {
 	flags := j.deviceProperties.Dxflags
 	if fullD8 {
@@ -144,10 +161,64 @@
 	return flags
 }
 
+func (j *Module) r8Flags(ctx android.ModuleContext, flags javaBuilderFlags) (r8Flags []string, r8Deps android.Paths) {
+	opt := j.deviceProperties.Optimize
+
+	// When an app contains references to APIs that are not in the SDK specified by
+	// its LOCAL_SDK_VERSION for example added by support library or by runtime
+	// classes added by desugar, we artifically raise the "SDK version" "linked" by
+	// ProGuard, to
+	// - suppress ProGuard warnings of referencing symbols unknown to the lower SDK version.
+	// - prevent ProGuard stripping subclass in the support library that extends class added in the higher SDK version.
+	// See b/20667396
+	var proguardRaiseDeps classpath
+	ctx.VisitDirectDepsWithTag(proguardRaiseTag, func(dep android.Module) {
+		proguardRaiseDeps = append(proguardRaiseDeps, dep.(Dependency).HeaderJars()...)
+	})
+
+	r8Flags = append(r8Flags, proguardRaiseDeps.FormJavaClassPath("-libraryjars"))
+	r8Flags = append(r8Flags, flags.bootClasspath.FormJavaClassPath("-libraryjars"))
+	r8Flags = append(r8Flags, flags.classpath.FormJavaClassPath("-libraryjars"))
+	r8Flags = append(r8Flags, "-forceprocessing")
+
+	flagFiles := android.Paths{
+		android.PathForSource(ctx, "build/make/core/proguard.flags"),
+	}
+
+	flagFiles = append(flagFiles, j.extraProguardFlagFiles...)
+	// TODO(ccross): static android library proguard files
+
+	r8Flags = append(r8Flags, android.JoinWithPrefix(flagFiles.Strings(), "-include "))
+	r8Deps = append(r8Deps, flagFiles...)
+
+	// TODO(b/70942988): This is included from build/make/core/proguard.flags
+	r8Deps = append(r8Deps, android.PathForSource(ctx,
+		"build/make/core/proguard_basic_keeps.flags"))
+
+	r8Flags = append(r8Flags, j.deviceProperties.Optimize.Proguard_flags...)
+
+	// TODO(ccross): Don't shrink app instrumentation tests by default.
+	if !Bool(opt.Shrink) {
+		r8Flags = append(r8Flags, "-dontshrink")
+	}
+
+	if !Bool(opt.Optimize) {
+		r8Flags = append(r8Flags, "-dontoptimize")
+	}
+
+	// TODO(ccross): error if obufscation + app instrumentation test.
+	if !Bool(opt.Obfuscate) {
+		r8Flags = append(r8Flags, "-dontobfuscate")
+	}
+
+	return r8Flags, r8Deps
+}
+
 func (j *Module) compileDex(ctx android.ModuleContext, flags javaBuilderFlags,
 	classesJar android.Path, jarName string) android.Path {
 
-	fullD8 := ctx.Config().UseD8Desugar()
+	useR8 := Bool(j.deviceProperties.Optimize.Enabled)
+	fullD8 := useR8 || ctx.Config().UseD8Desugar()
 
 	if !fullD8 {
 		classesJar = j.desugar(ctx, flags, classesJar, jarName)
@@ -159,22 +230,42 @@
 	javalibJar := android.PathForModuleOut(ctx, "dex", jarName)
 	outDir := android.PathForModuleOut(ctx, "dex")
 
-	rule := dx
-	desc := "dx"
-	if fullD8 {
-		rule = d8
-		desc = "d8"
+	if useR8 {
+		// TODO(ccross): if this is an instrumentation test of an obfuscated app, use the
+		// dictionary of the app and move the app from libraryjars to injars.
+		j.proguardDictionary = android.PathForModuleOut(ctx, "proguard_dictionary")
+		r8Flags, r8Deps := j.r8Flags(ctx, flags)
+		ctx.Build(pctx, android.BuildParams{
+			Rule:        r8,
+			Description: "r8",
+			Output:      javalibJar,
+			Input:       classesJar,
+			Implicits:   r8Deps,
+			Args: map[string]string{
+				"dxFlags": strings.Join(dxFlags, " "),
+				"r8Flags": strings.Join(r8Flags, " "),
+				"outDict": j.proguardDictionary.String(),
+				"outDir":  outDir.String(),
+			},
+		})
+	} else {
+		rule := dx
+		desc := "dx"
+		if fullD8 {
+			rule = d8
+			desc = "d8"
+		}
+		ctx.Build(pctx, android.BuildParams{
+			Rule:        rule,
+			Description: desc,
+			Output:      javalibJar,
+			Input:       classesJar,
+			Args: map[string]string{
+				"dxFlags": strings.Join(dxFlags, " "),
+				"outDir":  outDir.String(),
+			},
+		})
 	}
-	ctx.Build(pctx, android.BuildParams{
-		Rule:        rule,
-		Description: desc,
-		Output:      javalibJar,
-		Input:       classesJar,
-		Args: map[string]string{
-			"dxFlags": strings.Join(dxFlags, " "),
-			"outDir":  outDir.String(),
-		},
-	})
 
 	j.dexJarFile = javalibJar
 	return javalibJar
diff --git a/java/java.go b/java/java.go
index f06d81d..106284e 100644
--- a/java/java.go
+++ b/java/java.go
@@ -191,6 +191,32 @@
 		Profile *string
 	}
 
+	Optimize struct {
+		// If false, disable all optimization.  Defaults to true for apps, false for
+		// libraries and tests.
+		Enabled *bool
+
+		// If true, optimize for size by removing unused code.  Defaults to true for apps,
+		// false for libraries and tests.
+		Shrink *bool
+
+		// If true, optimize bytecode.  Defaults to false.
+		Optimize *bool
+
+		// If true, obfuscate bytecode.  Defaults to false.
+		Obfuscate *bool
+
+		// If true, do not use the flag files generated by aapt that automatically keep
+		// classes referenced by the app manifest.  Defaults to false.
+		No_aapt_flags *bool
+
+		// Flags to pass to proguard.
+		Proguard_flags []string
+
+		// Specifies the locations of files containing proguard flags.
+		Proguard_flags_files []string
+	}
+
 	// When targeting 1.9, override the modules to use with --system
 	System_modules *string
 }
@@ -216,6 +242,9 @@
 	// output file containing uninstrumented classes that will be instrumented by jacoco
 	jacocoReportClassesFile android.Path
 
+	// output file containing mapping of obfuscated names
+	proguardDictionary android.Path
+
 	// output file suitable for installing or running
 	outputFile android.Path
 
@@ -229,6 +258,9 @@
 	// list of .java files and srcjars that was passed to javac
 	compiledJavaSrcs android.Paths
 	compiledSrcJars  android.Paths
+
+	// list of extra progurad flag files
+	extraProguardFlagFiles android.Paths
 }
 
 func (j *Module) Srcs() android.Paths {
@@ -260,6 +292,7 @@
 	systemModulesTag = dependencyTag{name: "system modules"}
 	frameworkResTag  = dependencyTag{name: "framework-res"}
 	kotlinStdlibTag  = dependencyTag{name: "kotlin-stdlib"}
+	proguardRaiseTag = dependencyTag{name: "proguard-raise"}
 )
 
 type sdkDep struct {
@@ -377,6 +410,10 @@
 					ctx.AddDependency(ctx.Module(), systemModulesTag, sdkDep.systemModules)
 				}
 				ctx.AddDependency(ctx.Module(), bootClasspathTag, sdkDep.module)
+				if Bool(j.deviceProperties.Optimize.Enabled) {
+					ctx.AddDependency(ctx.Module(), proguardRaiseTag, config.DefaultBootclasspathLibraries...)
+					ctx.AddDependency(ctx.Module(), proguardRaiseTag, config.DefaultLibraries...)
+				}
 			}
 		} else if j.deviceProperties.System_modules == nil {
 			ctx.PropertyErrorf("no_standard_libs",
diff --git a/java/java_test.go b/java/java_test.go
index 6e14a70..e8298a2 100644
--- a/java/java_test.go
+++ b/java/java_test.go
@@ -157,6 +157,9 @@
 
 		"build/soong/scripts/jar-wrapper.sh": nil,
 
+		"build/make/core/proguard.flags":             nil,
+		"build/make/core/proguard_basic_keeps.flags": nil,
+
 		"jdk8/jre/lib/jce.jar": nil,
 		"jdk8/jre/lib/rt.jar":  nil,
 	}