diff --git a/android/apex.go b/android/apex.go
index 030fbdc..555cbb5 100644
--- a/android/apex.go
+++ b/android/apex.go
@@ -58,9 +58,6 @@
 	// to true.
 	UsePlatformApis bool
 
-	// The list of SDK modules that the containing apexBundle depends on.
-	RequiredSdks SdkRefs
-
 	// List of Apex variant names that this module is associated with. This initially is the
 	// same as the `ApexVariationName` field.  Then when multiple apex variants are merged in
 	// mergeApexVariations, ApexInfo struct of the merged variant holds the list of apexBundles
@@ -110,9 +107,6 @@
 // thus wouldn't be merged.
 func (i ApexInfo) mergedName(ctx PathContext) string {
 	name := "apex" + strconv.Itoa(i.MinSdkVersion.FinalOrFutureInt())
-	for _, sdk := range i.RequiredSdks {
-		name += "_" + sdk.Name + "_" + sdk.Version
-	}
 	return name
 }
 
@@ -850,25 +844,12 @@
 	}
 	return list
 }(map[string]int{
-	"android.net.ipsec.ike":                                    30,
-	"androidx.annotation_annotation-nodeps":                    29,
-	"androidx.arch.core_core-common-nodeps":                    29,
-	"androidx.collection_collection-nodeps":                    29,
-	"androidx.collection_collection-ktx-nodeps":                30,
-	"androidx.concurrent_concurrent-futures-nodeps":            30,
-	"androidx.lifecycle_lifecycle-common-java8-nodeps":         30,
-	"androidx.lifecycle_lifecycle-common-nodeps":               29,
-	"androidx.room_room-common-nodeps":                         30,
 	"androidx-constraintlayout_constraintlayout-solver-nodeps": 29,
 	"apache-commons-compress":                                  29,
 	"bouncycastle_ike_digests":                                 30,
 	"brotli-java":                                              29,
-	"captiveportal-lib":                                        28,
-	"error_prone_annotations":                                  30,
 	"flatbuffer_headers":                                       30,
-	"framework-permission":                                     30,
 	"gemmlowp_headers":                                         30,
-	"guava-listenablefuture-prebuilt-jar":                      30,
 	"ike-internals":                                            30,
 	"libbrotli":                                                30,
 	"libcrypto_static":                                         30,
@@ -884,14 +865,11 @@
 	"libtextclassifier_hash_headers":                           30,
 	"libtextclassifier_hash_static":                            30,
 	"libtflite_kernel_utils":                                   30,
-	"libwatchdog":                                              29,
 	"libzstd":                                                  30,
-	"metrics-constants-protos":                                 28,
 	"net-utils-framework-common":                               29,
 	"permissioncontroller-statsd":                              28,
 	"philox_random_headers":                                    30,
 	"philox_random":                                            30,
-	"service-permission":                                       30,
 	"tensorflow_headers":                                       30,
 	"xz-java":                                                  29,
 })
diff --git a/android/apex_test.go b/android/apex_test.go
index 1e2f3bd..0bf4c9c 100644
--- a/android/apex_test.go
+++ b/android/apex_test.go
@@ -33,10 +33,10 @@
 		{
 			name: "single",
 			in: []ApexInfo{
-				{"foo", FutureApiLevel, false, false, nil, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"foo", FutureApiLevel, false, false, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
 			},
 			wantMerged: []ApexInfo{
-				{"apex10000", FutureApiLevel, false, false, nil, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"apex10000", FutureApiLevel, false, false, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
 			},
 			wantAliases: [][2]string{
 				{"foo", "apex10000"},
@@ -45,25 +45,25 @@
 		{
 			name: "merge",
 			in: []ApexInfo{
-				{"foo", FutureApiLevel, false, false, SdkRefs{{"baz", "1"}}, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
-				{"bar", FutureApiLevel, false, false, SdkRefs{{"baz", "1"}}, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
+				{"foo", FutureApiLevel, false, false, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"bar", FutureApiLevel, false, false, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
 			},
 			wantMerged: []ApexInfo{
-				{"apex10000_baz_1", FutureApiLevel, false, false, SdkRefs{{"baz", "1"}}, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, false}},
+				{"apex10000", FutureApiLevel, false, false, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, false}},
 			wantAliases: [][2]string{
-				{"bar", "apex10000_baz_1"},
-				{"foo", "apex10000_baz_1"},
+				{"bar", "apex10000"},
+				{"foo", "apex10000"},
 			},
 		},
 		{
 			name: "don't merge version",
 			in: []ApexInfo{
-				{"foo", FutureApiLevel, false, false, nil, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
-				{"bar", uncheckedFinalApiLevel(30), false, false, nil, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
+				{"foo", FutureApiLevel, false, false, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"bar", uncheckedFinalApiLevel(30), false, false, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
 			},
 			wantMerged: []ApexInfo{
-				{"apex30", uncheckedFinalApiLevel(30), false, false, nil, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
-				{"apex10000", FutureApiLevel, false, false, nil, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"apex30", uncheckedFinalApiLevel(30), false, false, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
+				{"apex10000", FutureApiLevel, false, false, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
 			},
 			wantAliases: [][2]string{
 				{"bar", "apex30"},
@@ -73,11 +73,11 @@
 		{
 			name: "merge updatable",
 			in: []ApexInfo{
-				{"foo", FutureApiLevel, false, false, nil, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
-				{"bar", FutureApiLevel, true, false, nil, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
+				{"foo", FutureApiLevel, false, false, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"bar", FutureApiLevel, true, false, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
 			},
 			wantMerged: []ApexInfo{
-				{"apex10000", FutureApiLevel, true, false, nil, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, NotForPrebuiltApex},
+				{"apex10000", FutureApiLevel, true, false, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, NotForPrebuiltApex},
 			},
 			wantAliases: [][2]string{
 				{"bar", "apex10000"},
@@ -85,32 +85,17 @@
 			},
 		},
 		{
-			name: "don't merge sdks",
-			in: []ApexInfo{
-				{"foo", FutureApiLevel, false, false, SdkRefs{{"baz", "1"}}, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
-				{"bar", FutureApiLevel, false, false, SdkRefs{{"baz", "2"}}, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
-			},
-			wantMerged: []ApexInfo{
-				{"apex10000_baz_2", FutureApiLevel, false, false, SdkRefs{{"baz", "2"}}, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
-				{"apex10000_baz_1", FutureApiLevel, false, false, SdkRefs{{"baz", "1"}}, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
-			},
-			wantAliases: [][2]string{
-				{"bar", "apex10000_baz_2"},
-				{"foo", "apex10000_baz_1"},
-			},
-		},
-		{
 			name: "don't merge when for prebuilt_apex",
 			in: []ApexInfo{
-				{"foo", FutureApiLevel, false, false, nil, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
-				{"bar", FutureApiLevel, true, false, nil, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
+				{"foo", FutureApiLevel, false, false, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"bar", FutureApiLevel, true, false, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
 				// This one should not be merged in with the others because it is for
 				// a prebuilt_apex.
-				{"baz", FutureApiLevel, true, false, nil, []string{"baz"}, []string{"baz"}, nil, ForPrebuiltApex},
+				{"baz", FutureApiLevel, true, false, []string{"baz"}, []string{"baz"}, nil, ForPrebuiltApex},
 			},
 			wantMerged: []ApexInfo{
-				{"apex10000", FutureApiLevel, true, false, nil, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, NotForPrebuiltApex},
-				{"baz", FutureApiLevel, true, false, nil, []string{"baz"}, []string{"baz"}, nil, ForPrebuiltApex},
+				{"apex10000", FutureApiLevel, true, false, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, NotForPrebuiltApex},
+				{"baz", FutureApiLevel, true, false, []string{"baz"}, []string{"baz"}, nil, ForPrebuiltApex},
 			},
 			wantAliases: [][2]string{
 				{"bar", "apex10000"},
@@ -120,11 +105,11 @@
 		{
 			name: "merge different UsePlatformApis but don't allow using platform api",
 			in: []ApexInfo{
-				{"foo", FutureApiLevel, false, false, nil, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
-				{"bar", FutureApiLevel, false, true, nil, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
+				{"foo", FutureApiLevel, false, false, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"bar", FutureApiLevel, false, true, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
 			},
 			wantMerged: []ApexInfo{
-				{"apex10000", FutureApiLevel, false, false, nil, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, NotForPrebuiltApex},
+				{"apex10000", FutureApiLevel, false, false, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, NotForPrebuiltApex},
 			},
 			wantAliases: [][2]string{
 				{"bar", "apex10000"},
@@ -134,11 +119,11 @@
 		{
 			name: "merge same UsePlatformApis and allow using platform api",
 			in: []ApexInfo{
-				{"foo", FutureApiLevel, false, true, nil, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
-				{"bar", FutureApiLevel, false, true, nil, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
+				{"foo", FutureApiLevel, false, true, []string{"foo"}, []string{"foo"}, nil, NotForPrebuiltApex},
+				{"bar", FutureApiLevel, false, true, []string{"bar"}, []string{"bar"}, nil, NotForPrebuiltApex},
 			},
 			wantMerged: []ApexInfo{
-				{"apex10000", FutureApiLevel, false, true, nil, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, NotForPrebuiltApex},
+				{"apex10000", FutureApiLevel, false, true, []string{"bar", "foo"}, []string{"bar", "foo"}, nil, NotForPrebuiltApex},
 			},
 			wantAliases: [][2]string{
 				{"bar", "apex10000"},
diff --git a/android/bazel.go b/android/bazel.go
index 4ef8d78..67002ec 100644
--- a/android/bazel.go
+++ b/android/bazel.go
@@ -338,9 +338,19 @@
 	return false
 }
 
-// MixedBuildsEnabled checks that a module is ready to be replaced by a
+// MixedBuildsEnabled returns true if a module is ready to be replaced by a
+// converted or handcrafted Bazel target. As a side effect, calling this
+// method will also log whether this module is mixed build enabled for
+// metrics reporting.
+func MixedBuildsEnabled(ctx ModuleContext) bool {
+	mixedBuildEnabled := mixedBuildPossible(ctx)
+	ctx.Config().LogMixedBuild(ctx, mixedBuildEnabled)
+	return mixedBuildEnabled
+}
+
+// mixedBuildPossible returns true if a module is ready to be replaced by a
 // converted or handcrafted Bazel target.
-func (b *BazelModuleBase) MixedBuildsEnabled(ctx ModuleContext) bool {
+func mixedBuildPossible(ctx ModuleContext) bool {
 	if ctx.Os() == Windows {
 		// Windows toolchains are not currently supported.
 		return false
diff --git a/android/config.go b/android/config.go
index ee058e8..d695217 100644
--- a/android/config.go
+++ b/android/config.go
@@ -170,6 +170,10 @@
 	ninjaFileDepsSet sync.Map
 
 	OncePer
+
+	mixedBuildsLock           sync.Mutex
+	mixedBuildEnabledModules  map[string]struct{}
+	mixedBuildDisabledModules map[string]struct{}
 }
 
 type deviceConfig struct {
@@ -375,7 +379,9 @@
 		// passed to PathForSource or PathForModuleSrc.
 		TestAllowNonExistentPaths: true,
 
-		BazelContext: noopBazelContext{},
+		BazelContext:              noopBazelContext{},
+		mixedBuildDisabledModules: make(map[string]struct{}),
+		mixedBuildEnabledModules:  make(map[string]struct{}),
 	}
 	config.deviceConfig = &deviceConfig{
 		config: config,
@@ -466,8 +472,10 @@
 		runGoTests:        runGoTests,
 		multilibConflicts: make(map[ArchType]bool),
 
-		moduleListFile: moduleListFile,
-		fs:             pathtools.NewOsFs(absSrcDir),
+		moduleListFile:            moduleListFile,
+		fs:                        pathtools.NewOsFs(absSrcDir),
+		mixedBuildDisabledModules: make(map[string]struct{}),
+		mixedBuildEnabledModules:  make(map[string]struct{}),
 	}
 
 	config.deviceConfig = &deviceConfig{
@@ -2038,3 +2046,14 @@
 func (c *config) UseHostMusl() bool {
 	return Bool(c.productVariables.HostMusl)
 }
+
+func (c *config) LogMixedBuild(ctx ModuleContext, useBazel bool) {
+	moduleName := ctx.Module().Name()
+	c.mixedBuildsLock.Lock()
+	defer c.mixedBuildsLock.Unlock()
+	if useBazel {
+		c.mixedBuildEnabledModules[moduleName] = struct{}{}
+	} else {
+		c.mixedBuildDisabledModules[moduleName] = struct{}{}
+	}
+}
diff --git a/android/filegroup.go b/android/filegroup.go
index 50356d1..1bf5e07 100644
--- a/android/filegroup.go
+++ b/android/filegroup.go
@@ -115,7 +115,7 @@
 }
 
 func (fg *fileGroup) maybeGenerateBazelBuildActions(ctx ModuleContext) {
-	if !fg.MixedBuildsEnabled(ctx) {
+	if !MixedBuildsEnabled(ctx) {
 		return
 	}
 
diff --git a/android/metrics.go b/android/metrics.go
index 9038bde..1580f82 100644
--- a/android/metrics.go
+++ b/android/metrics.go
@@ -17,6 +17,7 @@
 import (
 	"io/ioutil"
 	"runtime"
+	"sort"
 
 	"github.com/google/blueprint/metrics"
 	"google.golang.org/protobuf/proto"
@@ -78,6 +79,23 @@
 		}
 		metrics.Events = append(metrics.Events, &perfInfo)
 	}
+	mixedBuildsInfo := soong_metrics_proto.MixedBuildsInfo{}
+	mixedBuildEnabledModules := make([]string, 0, len(config.mixedBuildEnabledModules))
+	for module, _ := range config.mixedBuildEnabledModules {
+		mixedBuildEnabledModules = append(mixedBuildEnabledModules, module)
+	}
+
+	mixedBuildDisabledModules := make([]string, 0, len(config.mixedBuildDisabledModules))
+	for module, _ := range config.mixedBuildDisabledModules {
+		mixedBuildDisabledModules = append(mixedBuildDisabledModules, module)
+	}
+	// Sorted for deterministic output.
+	sort.Strings(mixedBuildEnabledModules)
+	sort.Strings(mixedBuildDisabledModules)
+
+	mixedBuildsInfo.MixedBuildEnabledModules = mixedBuildEnabledModules
+	mixedBuildsInfo.MixedBuildDisabledModules = mixedBuildDisabledModules
+	metrics.MixedBuildsInfo = &mixedBuildsInfo
 
 	return metrics
 }
diff --git a/android/sdk.go b/android/sdk.go
index 1d63d7a..3a56240 100644
--- a/android/sdk.go
+++ b/android/sdk.go
@@ -23,24 +23,8 @@
 	"github.com/google/blueprint/proptools"
 )
 
-// RequiredSdks provides access to the set of SDKs required by an APEX and its contents.
-//
-// Extracted from SdkAware to make it easier to define custom subsets of the
-// SdkAware interface and improve code navigation within the IDE.
-//
-// In addition to its use in SdkAware this interface must also be implemented by
-// APEX to specify the SDKs required by that module and its contents. e.g. APEX
-// is expected to implement RequiredSdks() by reading its own properties like
-// `uses_sdks`.
-type RequiredSdks interface {
-	// RequiredSdks returns the set of SDKs required by an APEX and its contents.
-	RequiredSdks() SdkRefs
-}
-
 // sdkAwareWithoutModule is provided simply to improve code navigation with the IDE.
 type sdkAwareWithoutModule interface {
-	RequiredSdks
-
 	// SdkMemberComponentName will return the name to use for a component of this module based on the
 	// base name of this module.
 	//
@@ -81,7 +65,6 @@
 
 	ContainingSdk() SdkRef
 	MemberName() string
-	BuildWithSdks(sdks SdkRefs)
 }
 
 // SdkAware is the interface that must be supported by any module to become a member of SDK or to be
@@ -150,9 +133,6 @@
 	// The SDK that this module is a member of. nil if it is not a member of any SDK
 	ContainingSdk *SdkRef `blueprint:"mutated"`
 
-	// The list of SDK names and versions that are used to build this module
-	RequiredSdks SdkRefs `blueprint:"mutated"`
-
 	// Name of the module that this sdk member is representing
 	Sdk_member_name *string
 }
@@ -208,16 +188,6 @@
 	return proptools.String(s.properties.Sdk_member_name)
 }
 
-// BuildWithSdks is used to mark that this module has to be built with the given SDK(s).
-func (s *SdkBase) BuildWithSdks(sdks SdkRefs) {
-	s.properties.RequiredSdks = sdks
-}
-
-// RequiredSdks returns the SDK(s) that this module has to be built with
-func (s *SdkBase) RequiredSdks() SdkRefs {
-	return s.properties.RequiredSdks
-}
-
 // InitSdkAwareModule initializes the SdkBase struct. This must be called by all modules including
 // SdkBase.
 func InitSdkAwareModule(m SdkAware) {
diff --git a/apex/apex.go b/apex/apex.go
index c779868..73a3fc2 100644
--- a/apex/apex.go
+++ b/apex/apex.go
@@ -159,12 +159,6 @@
 	// or else conflicting build rules may be created.
 	Multi_install_skip_symbol_files *bool
 
-	// List of SDKs that are used to build this APEX. A reference to an SDK should be either
-	// `name#version` or `name` which is an alias for `name#current`. If left empty,
-	// `platform#current` is implied. This value affects all modules included in this APEX. In
-	// other words, they are also built with the SDKs specified here.
-	Uses_sdks []string
-
 	// The type of APEX to build. Controls what the APEX payload is. Either 'image', 'zip' or
 	// 'both'. When set to image, contents are stored in a filesystem image inside a zip
 	// container. When set to zip, contents are stored in a zip container directly. This type is
@@ -791,19 +785,6 @@
 	commonVariation := ctx.Config().AndroidCommonTarget.Variations()
 	ctx.AddFarVariationDependencies(commonVariation, fsTag, a.properties.Filesystems...)
 	ctx.AddFarVariationDependencies(commonVariation, compatConfigTag, a.properties.Compat_configs...)
-
-	// Marks that this APEX (in fact all the modules in it) has to be built with the given SDKs.
-	// This field currently isn't used.
-	// TODO(jiyong): consider dropping this feature
-	// TODO(jiyong): ensure that all apexes are with non-empty uses_sdks
-	if len(a.properties.Uses_sdks) > 0 {
-		sdkRefs := []android.SdkRef{}
-		for _, str := range a.properties.Uses_sdks {
-			parsed := android.ParseSdkRef(ctx, str, "uses_sdks")
-			sdkRefs = append(sdkRefs, parsed)
-		}
-		a.BuildWithSdks(sdkRefs)
-	}
 }
 
 // DepsMutator for the overridden properties.
@@ -968,7 +949,6 @@
 	apexInfo := android.ApexInfo{
 		ApexVariationName: apexVariationName,
 		MinSdkVersion:     minSdkVersion,
-		RequiredSdks:      a.RequiredSdks(),
 		Updatable:         a.Updatable(),
 		UsePlatformApis:   a.UsePlatformApis(),
 		InApexVariants:    []string{apexVariationName},
diff --git a/build_kzip.bash b/build_kzip.bash
index aff2d6d..6219021 100755
--- a/build_kzip.bash
+++ b/build_kzip.bash
@@ -36,7 +36,7 @@
 declare -r out="${OUT_DIR:-out}"
 
 # Build extraction files for C++ and Java. Build `merge_zips` which we use later.
-build/soong/soong_ui.bash --build-mode --all-modules --dir=$PWD -k merge_zips xref_cxx xref_java
+build/soong/soong_ui.bash --build-mode --all-modules --dir=$PWD -k merge_zips xref_cxx xref_java xref_rust
 
 # Build extraction file for Go the files in build/{blueprint,soong} directories.
 declare -r abspath_out=$(realpath "${out}")
@@ -44,7 +44,7 @@
 declare -r go_root=$(realpath prebuilts/go/linux-x86)
 declare -r source_root=$PWD
 
-# TODO(asmundak): Until b/182183061 is fixed, default corpus has to be specified 
+# TODO(asmundak): Until b/182183061 is fixed, default corpus has to be specified
 # in the rules file. Generate this file on the fly with corpus value set from the
 # environment variable.
 for dir in blueprint soong; do
diff --git a/cc/cc.go b/cc/cc.go
index c2d0f6e..8606920 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -48,7 +48,6 @@
 		ctx.BottomUp("vndk", VndkMutator).Parallel()
 		ctx.BottomUp("link", LinkageMutator).Parallel()
 		ctx.BottomUp("test_per_src", TestPerSrcMutator).Parallel()
-		ctx.BottomUp("version_selector", versionSelectorMutator).Parallel()
 		ctx.BottomUp("version", versionMutator).Parallel()
 		ctx.BottomUp("begin", BeginMutator).Parallel()
 		ctx.BottomUp("sysprop_cc", SyspropMutator).Parallel()
@@ -1789,7 +1788,7 @@
 	bazelActionsUsed := false
 	// Mixed builds mode is disabled for modules outside of device OS.
 	// TODO(b/200841190): Support non-device OS in mixed builds.
-	if c.MixedBuildsEnabled(actx) && c.bazelHandler != nil {
+	if android.MixedBuildsEnabled(actx) && c.bazelHandler != nil {
 		bazelActionsUsed = c.bazelHandler.GenerateBazelBuildActions(actx, bazelModuleLabel)
 	}
 	return bazelActionsUsed
@@ -2117,7 +2116,7 @@
 
 	variations = append([]blueprint.Variation(nil), variations...)
 
-	if version != "" && CanBeOrLinkAgainstVersionVariants(mod) {
+	if version != "" && canBeOrLinkAgainstVersionVariants(mod) {
 		// Version is explicitly specified. i.e. libFoo#30
 		variations = append(variations, blueprint.Variation{Mutator: "version", Variation: version})
 		if tag, ok := depTag.(libraryDependencyTag); ok {
diff --git a/cc/config/global.go b/cc/config/global.go
index dc6310c..3caf327 100644
--- a/cc/config/global.go
+++ b/cc/config/global.go
@@ -286,8 +286,8 @@
 
 	// prebuilts/clang default settings.
 	ClangDefaultBase         = "prebuilts/clang/host"
-	ClangDefaultVersion      = "clang-r450784e"
-	ClangDefaultShortVersion = "14.0.7"
+	ClangDefaultVersion      = "clang-r450784d"
+	ClangDefaultShortVersion = "14.0.6"
 
 	// Directories with warnings from Android.bp files.
 	WarningAllowedProjects = []string{
diff --git a/cc/library.go b/cc/library.go
index 0abcb6f..fdbbccb 100644
--- a/cc/library.go
+++ b/cc/library.go
@@ -2344,7 +2344,7 @@
 	}
 }
 
-func CanBeOrLinkAgainstVersionVariants(module interface {
+func canBeOrLinkAgainstVersionVariants(module interface {
 	Host() bool
 	InRamdisk() bool
 	InVendorRamdisk() bool
@@ -2352,15 +2352,14 @@
 	return !module.Host() && !module.InRamdisk() && !module.InVendorRamdisk()
 }
 
-func CanBeVersionVariant(module interface {
+func canBeVersionVariant(module interface {
 	Host() bool
 	InRamdisk() bool
 	InVendorRamdisk() bool
-	InRecovery() bool
 	CcLibraryInterface() bool
 	Shared() bool
 }) bool {
-	return CanBeOrLinkAgainstVersionVariants(module) &&
+	return canBeOrLinkAgainstVersionVariants(module) &&
 		module.CcLibraryInterface() && module.Shared()
 }
 
@@ -2371,37 +2370,41 @@
 	return nil
 }
 
-// versionSelector normalizes the versions in the Stubs.Versions property into MutatedProperties.AllStubsVersions.
-func versionSelectorMutator(mctx android.BottomUpMutatorContext) {
-	if library := moduleLibraryInterface(mctx.Module()); library != nil && CanBeVersionVariant(mctx.Module().(*Module)) {
-		if library.buildShared() {
-			versions := library.stubsVersions(mctx)
-			if len(versions) > 0 {
-				normalizeVersions(mctx, versions)
-				if mctx.Failed() {
-					return
-				}
-				// Set the versions on the pre-mutated module so they can be read by any llndk modules that
-				// depend on the implementation library and haven't been mutated yet.
-				library.setAllStubsVersions(versions)
-			}
-		}
+// setStubsVersions normalizes the versions in the Stubs.Versions property into MutatedProperties.AllStubsVersions.
+func setStubsVersions(mctx android.BottomUpMutatorContext, library libraryInterface, module *Module) {
+	if !library.buildShared() || !canBeVersionVariant(module) {
+		return
 	}
+	versions := library.stubsVersions(mctx)
+	if len(versions) <= 0 {
+		return
+	}
+	normalizeVersions(mctx, versions)
+	if mctx.Failed() {
+		return
+	}
+	// Set the versions on the pre-mutated module so they can be read by any llndk modules that
+	// depend on the implementation library and haven't been mutated yet.
+	library.setAllStubsVersions(versions)
 }
 
 // versionMutator splits a module into the mandatory non-stubs variant
 // (which is unnamed) and zero or more stubs variants.
 func versionMutator(mctx android.BottomUpMutatorContext) {
-	if library := moduleLibraryInterface(mctx.Module()); library != nil && CanBeVersionVariant(mctx.Module().(*Module)) {
+	if mctx.Os() != android.Android {
+		return
+	}
+
+	m, ok := mctx.Module().(*Module)
+	if library := moduleLibraryInterface(mctx.Module()); library != nil && canBeVersionVariant(m) {
+		setStubsVersions(mctx, library, m)
+
 		createVersionVariations(mctx, library.allStubsVersions())
 		return
 	}
 
-	if m, ok := mctx.Module().(*Module); ok {
+	if ok {
 		if m.SplitPerApiLevel() && m.IsSdkVariant() {
-			if mctx.Os() != android.Android {
-				return
-			}
 			createPerApiVersionVariations(mctx, m.MinSdkVersion())
 		}
 	}
diff --git a/genrule/genrule.go b/genrule/genrule.go
index c52ddee..3531ee6 100644
--- a/genrule/genrule.go
+++ b/genrule/genrule.go
@@ -578,7 +578,7 @@
 
 	bazelModuleLabel := g.GetBazelLabel(ctx, g)
 	bazelActionsUsed := false
-	if g.MixedBuildsEnabled(ctx) {
+	if android.MixedBuildsEnabled(ctx) {
 		bazelActionsUsed = g.GenerateBazelBuildActions(ctx, bazelModuleLabel)
 	}
 	if !bazelActionsUsed {
diff --git a/java/app.go b/java/app.go
index 2b52eab..d0a1db0 100755
--- a/java/app.go
+++ b/java/app.go
@@ -900,6 +900,7 @@
 	module.Module.dexProperties.Optimize.Shrink = proptools.BoolPtr(true)
 
 	module.Module.properties.Instrument = true
+	module.Module.properties.Supports_static_instrumentation = true
 	module.Module.properties.Installable = proptools.BoolPtr(true)
 
 	module.addHostAndDeviceProperties()
@@ -1019,6 +1020,7 @@
 	module.Module.dexProperties.Optimize.EnabledByDefault = true
 
 	module.Module.properties.Instrument = true
+	module.Module.properties.Supports_static_instrumentation = true
 	module.Module.properties.Installable = proptools.BoolPtr(true)
 	module.appProperties.Use_embedded_native_libs = proptools.BoolPtr(true)
 	module.appProperties.AlwaysPackageNativeLibs = true
diff --git a/java/base.go b/java/base.go
index 245ffbb..ff1ce85 100644
--- a/java/base.go
+++ b/java/base.go
@@ -170,6 +170,9 @@
 	}
 
 	Instrument bool `blueprint:"mutated"`
+	// If true, then the module supports statically including the jacocoagent
+	// into the library.
+	Supports_static_instrumentation bool `blueprint:"mutated"`
 
 	// List of files to include in the META-INF/services folder of the resulting jar.
 	Services []string `android:"path,arch_variant"`
@@ -602,7 +605,8 @@
 }
 
 func (j *Module) shouldInstrumentStatic(ctx android.BaseModuleContext) bool {
-	return j.shouldInstrument(ctx) &&
+	return j.properties.Supports_static_instrumentation &&
+		j.shouldInstrument(ctx) &&
 		(ctx.Config().IsEnvTrue("EMMA_INSTRUMENT_STATIC") ||
 			ctx.Config().UnbundledBuild())
 }
diff --git a/java/kotlin.go b/java/kotlin.go
index eff5bb5..903c624 100644
--- a/java/kotlin.go
+++ b/java/kotlin.go
@@ -175,6 +175,7 @@
 
 	var deps android.Paths
 	deps = append(deps, flags.kotlincClasspath...)
+	deps = append(deps, flags.kotlincDeps...)
 	deps = append(deps, srcJars...)
 	deps = append(deps, flags.processorPath...)
 	deps = append(deps, commonSrcFiles...)
diff --git a/java/kotlin_test.go b/java/kotlin_test.go
index f9ff982..435d782 100644
--- a/java/kotlin_test.go
+++ b/java/kotlin_test.go
@@ -325,6 +325,7 @@
 		java_library {
 			name: "withcompose",
 			srcs: ["a.kt"],
+			plugins: ["plugin"],
 			static_libs: ["androidx.compose.runtime_runtime"],
 		}
 
@@ -332,6 +333,10 @@
 			name: "nocompose",
 			srcs: ["a.kt"],
 		}
+
+		java_plugin {
+			name: "plugin",
+		}
 	`)
 
 	buildOS := result.Config.BuildOS.String()
@@ -346,6 +351,9 @@
 	android.AssertStringDoesContain(t, "missing compose compiler plugin",
 		withCompose.VariablesForTestsRelativeToTop()["kotlincFlags"], "-Xplugin="+composeCompiler.String())
 
+	android.AssertStringListContains(t, "missing kapt compose compiler dependency",
+		withCompose.Rule("kapt").Implicits.Strings(), composeCompiler.String())
+
 	android.AssertStringListDoesNotContain(t, "unexpected compose compiler dependency",
 		noCompose.Rule("kotlinc").Implicits.Strings(), composeCompiler.String())
 
diff --git a/rust/binary.go b/rust/binary.go
index 0dc320e..41110f9 100644
--- a/rust/binary.go
+++ b/rust/binary.go
@@ -128,11 +128,11 @@
 	return Bool(binary.baseCompiler.Properties.Prefer_rlib) || Bool(binary.Properties.Static_executable)
 }
 
-func (binary *binaryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) android.Path {
+func (binary *binaryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) buildOutput {
 	fileName := binary.getStem(ctx) + ctx.toolchain().ExecutableSuffix()
 	srcPath, _ := srcPathFromModuleSrcs(ctx, binary.baseCompiler.Properties.Srcs)
 	outputFile := android.PathForModuleOut(ctx, fileName)
-	ret := outputFile
+	ret := buildOutput{outputFile: outputFile}
 
 	flags.RustFlags = append(flags.RustFlags, deps.depFlags...)
 	flags.LinkFlags = append(flags.LinkFlags, deps.depLinkFlags...)
@@ -147,8 +147,7 @@
 	}
 	binary.baseCompiler.unstrippedOutputFile = outputFile
 
-	TransformSrcToBinary(ctx, srcPath, deps, flags, outputFile)
-
+	ret.kytheFile = TransformSrcToBinary(ctx, srcPath, deps, flags, outputFile).kytheFile
 	return ret
 }
 
diff --git a/rust/bindgen.go b/rust/bindgen.go
index c2b0512..b4626a0 100644
--- a/rust/bindgen.go
+++ b/rust/bindgen.go
@@ -30,7 +30,7 @@
 	defaultBindgenFlags = []string{""}
 
 	// bindgen should specify its own Clang revision so updating Clang isn't potentially blocked on bindgen failures.
-	bindgenClangVersion = "clang-r445002"
+	bindgenClangVersion = "clang-r450784d"
 
 	_ = pctx.VariableFunc("bindgenClangVersion", func(ctx android.PackageVarContext) string {
 		if override := ctx.Config().Getenv("LLVM_BINDGEN_PREBUILTS_VERSION"); override != "" {
diff --git a/rust/builder.go b/rust/builder.go
index 20ca5db..7dd9dd2 100644
--- a/rust/builder.go
+++ b/rust/builder.go
@@ -83,10 +83,37 @@
 			RspfileContent: "$in",
 		},
 		"outDir")
+
+	// Cross-referencing:
+	_ = pctx.SourcePathVariable("rustExtractor",
+		"prebuilts/build-tools/${config.HostPrebuiltTag}/bin/rust_extractor")
+	_ = pctx.VariableFunc("kytheCorpus",
+		func(ctx android.PackageVarContext) string { return ctx.Config().XrefCorpusName() })
+	_ = pctx.VariableFunc("kytheCuEncoding",
+		func(ctx android.PackageVarContext) string { return ctx.Config().XrefCuEncoding() })
+	_            = pctx.SourcePathVariable("kytheVnames", "build/soong/vnames.json")
+	kytheExtract = pctx.AndroidStaticRule("kythe",
+		blueprint.RuleParams{
+			Command: `KYTHE_CORPUS=${kytheCorpus} ` +
+				`KYTHE_OUTPUT_FILE=$out ` +
+				`KYTHE_VNAMES=$kytheVnames ` +
+				`KYTHE_KZIP_ENCODING=${kytheCuEncoding} ` +
+				`KYTHE_CANONICALIZE_VNAME_PATHS=prefer-relative ` +
+				`$rustExtractor $envVars ` +
+				`$rustcCmd ` +
+				`-C linker=${config.RustLinker} ` +
+				`-C link-args="${crtBegin} ${config.RustLinkerArgs} ${linkFlags} ${crtEnd}" ` +
+				`$in ${libFlags} $rustcFlags`,
+			CommandDeps:    []string{"$rustExtractor", "$kytheVnames"},
+			Rspfile:        "${out}.rsp",
+			RspfileContent: "$in",
+		},
+		"rustcFlags", "linkFlags", "libFlags", "crtBegin", "crtEnd", "envVars")
 )
 
 type buildOutput struct {
 	outputFile android.Path
+	kytheFile  android.Path
 }
 
 func init() {
@@ -324,6 +351,25 @@
 		},
 	})
 
+	if flags.EmitXrefs {
+		kytheFile := android.PathForModuleOut(ctx, outputFile.Base()+".kzip")
+		ctx.Build(pctx, android.BuildParams{
+			Rule:        kytheExtract,
+			Description: "Xref Rust extractor " + main.Rel(),
+			Output:      kytheFile,
+			Inputs:      inputs,
+			Implicits:   implicits,
+			Args: map[string]string{
+				"rustcFlags": strings.Join(rustcFlags, " "),
+				"linkFlags":  strings.Join(linkFlags, " "),
+				"libFlags":   strings.Join(libFlags, " "),
+				"crtBegin":   strings.Join(deps.CrtBegin.Strings(), " "),
+				"crtEnd":     strings.Join(deps.CrtEnd.Strings(), " "),
+				"envVars":    strings.Join(envVars, " "),
+			},
+		})
+		output.kytheFile = kytheFile
+	}
 	return output
 }
 
diff --git a/rust/compiler.go b/rust/compiler.go
index 19499fa..bcd58c8 100644
--- a/rust/compiler.go
+++ b/rust/compiler.go
@@ -304,6 +304,7 @@
 	flags.GlobalRustFlags = append(flags.GlobalRustFlags, config.GlobalRustFlags...)
 	flags.GlobalRustFlags = append(flags.GlobalRustFlags, ctx.toolchain().ToolchainRustFlags())
 	flags.GlobalLinkFlags = append(flags.GlobalLinkFlags, ctx.toolchain().ToolchainLinkFlags())
+	flags.EmitXrefs = ctx.Config().EmitXrefRules()
 
 	if ctx.Host() && !ctx.Windows() {
 		rpathPrefix := `\$$ORIGIN/`
@@ -324,7 +325,7 @@
 	return flags
 }
 
-func (compiler *baseCompiler) compile(ctx ModuleContext, flags Flags, deps PathDeps) android.Path {
+func (compiler *baseCompiler) compile(ctx ModuleContext, flags Flags, deps PathDeps) buildOutput {
 	panic(fmt.Errorf("baseCrater doesn't know how to crate things!"))
 }
 
diff --git a/rust/config/global.go b/rust/config/global.go
index 6bfa9cf..d11665c 100644
--- a/rust/config/global.go
+++ b/rust/config/global.go
@@ -50,6 +50,7 @@
 		"-C force-unwind-tables=yes",
 		// Use v0 mangling to distinguish from C++ symbols
 		"-C symbol-mangling-version=v0",
+		"--color always",
 	}
 
 	deviceGlobalRustFlags = []string{
diff --git a/rust/library.go b/rust/library.go
index 62eaefd..1286549 100644
--- a/rust/library.go
+++ b/rust/library.go
@@ -474,8 +474,9 @@
 	return flags
 }
 
-func (library *libraryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) android.Path {
-	var outputFile, ret android.ModuleOutPath
+func (library *libraryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) buildOutput {
+	var outputFile android.ModuleOutPath
+	var ret buildOutput
 	var fileName string
 	srcPath := library.srcPath(ctx, deps)
 
@@ -487,19 +488,19 @@
 	if library.rlib() {
 		fileName = library.getStem(ctx) + ctx.toolchain().RlibSuffix()
 		outputFile = android.PathForModuleOut(ctx, fileName)
-		ret = outputFile
+		ret.outputFile = outputFile
 	} else if library.dylib() {
 		fileName = library.getStem(ctx) + ctx.toolchain().DylibSuffix()
 		outputFile = android.PathForModuleOut(ctx, fileName)
-		ret = outputFile
+		ret.outputFile = outputFile
 	} else if library.static() {
 		fileName = library.getStem(ctx) + ctx.toolchain().StaticLibSuffix()
 		outputFile = android.PathForModuleOut(ctx, fileName)
-		ret = outputFile
+		ret.outputFile = outputFile
 	} else if library.shared() {
 		fileName = library.sharedLibFilename(ctx)
 		outputFile = android.PathForModuleOut(ctx, fileName)
-		ret = outputFile
+		ret.outputFile = outputFile
 	}
 
 	if !library.rlib() && !library.static() && library.stripper.NeedsStrip(ctx) {
@@ -524,13 +525,13 @@
 
 	// Call the appropriate builder for this library type
 	if library.rlib() {
-		TransformSrctoRlib(ctx, srcPath, deps, flags, outputFile)
+		ret.kytheFile = TransformSrctoRlib(ctx, srcPath, deps, flags, outputFile).kytheFile
 	} else if library.dylib() {
-		TransformSrctoDylib(ctx, srcPath, deps, flags, outputFile)
+		ret.kytheFile = TransformSrctoDylib(ctx, srcPath, deps, flags, outputFile).kytheFile
 	} else if library.static() {
-		TransformSrctoStatic(ctx, srcPath, deps, flags, outputFile)
+		ret.kytheFile = TransformSrctoStatic(ctx, srcPath, deps, flags, outputFile).kytheFile
 	} else if library.shared() {
-		TransformSrctoShared(ctx, srcPath, deps, flags, outputFile)
+		ret.kytheFile = TransformSrctoShared(ctx, srcPath, deps, flags, outputFile).kytheFile
 	}
 
 	if library.rlib() || library.dylib() {
@@ -572,7 +573,7 @@
 	return ret
 }
 
-func (library *libraryDecorator) srcPath(ctx ModuleContext, deps PathDeps) android.Path {
+func (library *libraryDecorator) srcPath(ctx ModuleContext, _ PathDeps) android.Path {
 	if library.sourceProvider != nil {
 		// Assume the first source from the source provider is the library entry point.
 		return library.sourceProvider.Srcs()[0]
diff --git a/rust/prebuilt.go b/rust/prebuilt.go
index 6cdd07d..fe9d0b5 100644
--- a/rust/prebuilt.go
+++ b/rust/prebuilt.go
@@ -145,7 +145,7 @@
 		&prebuilt.Properties)
 }
 
-func (prebuilt *prebuiltLibraryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) android.Path {
+func (prebuilt *prebuiltLibraryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) buildOutput {
 	prebuilt.flagExporter.exportLinkDirs(android.PathsForModuleSrc(ctx, prebuilt.Properties.Link_dirs).Strings()...)
 	prebuilt.flagExporter.setProvider(ctx)
 
@@ -154,7 +154,7 @@
 		ctx.PropertyErrorf("srcs", "prebuilt libraries can only have one entry in srcs (the prebuilt path)")
 	}
 	prebuilt.baseCompiler.unstrippedOutputFile = srcPath
-	return srcPath
+	return buildOutput{outputFile: srcPath}
 }
 
 func (prebuilt *prebuiltLibraryDecorator) rustdoc(ctx ModuleContext, flags Flags,
@@ -202,7 +202,7 @@
 		&prebuilt.Properties)
 }
 
-func (prebuilt *prebuiltProcMacroDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) android.Path {
+func (prebuilt *prebuiltProcMacroDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) buildOutput {
 	prebuilt.flagExporter.exportLinkDirs(android.PathsForModuleSrc(ctx, prebuilt.Properties.Link_dirs).Strings()...)
 	prebuilt.flagExporter.setProvider(ctx)
 
@@ -211,7 +211,7 @@
 		ctx.PropertyErrorf("srcs", "prebuilt libraries can only have one entry in srcs (the prebuilt path)")
 	}
 	prebuilt.baseCompiler.unstrippedOutputFile = srcPath
-	return srcPath
+	return buildOutput{outputFile: srcPath}
 }
 
 func (prebuilt *prebuiltProcMacroDecorator) rustdoc(ctx ModuleContext, flags Flags,
diff --git a/rust/proc_macro.go b/rust/proc_macro.go
index f8a4bbd..832b62c 100644
--- a/rust/proc_macro.go
+++ b/rust/proc_macro.go
@@ -70,14 +70,14 @@
 	return flags
 }
 
-func (procMacro *procMacroDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) android.Path {
+func (procMacro *procMacroDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) buildOutput {
 	fileName := procMacro.getStem(ctx) + ctx.toolchain().ProcMacroSuffix()
 	outputFile := android.PathForModuleOut(ctx, fileName)
 
 	srcPath, _ := srcPathFromModuleSrcs(ctx, procMacro.baseCompiler.Properties.Srcs)
-	TransformSrctoProcMacro(ctx, srcPath, deps, flags, outputFile)
+	ret := TransformSrctoProcMacro(ctx, srcPath, deps, flags, outputFile)
 	procMacro.baseCompiler.unstrippedOutputFile = outputFile
-	return outputFile
+	return ret
 }
 
 func (procMacro *procMacroDecorator) getStem(ctx ModuleContext) string {
diff --git a/rust/rust.go b/rust/rust.go
index c4fd148..48419eb 100644
--- a/rust/rust.go
+++ b/rust/rust.go
@@ -15,6 +15,7 @@
 package rust
 
 import (
+	"android/soong/bloaty"
 	"fmt"
 	"strings"
 
@@ -22,7 +23,6 @@
 	"github.com/google/blueprint/proptools"
 
 	"android/soong/android"
-	"android/soong/bloaty"
 	"android/soong/cc"
 	cc_config "android/soong/cc/config"
 	"android/soong/fuzz"
@@ -52,6 +52,7 @@
 	})
 	pctx.Import("android/soong/rust/config")
 	pctx.ImportAs("cc_config", "android/soong/cc/config")
+	android.InitRegistrationContext.RegisterSingletonType("kythe_rust_extract", kytheExtractRustFactory)
 }
 
 type Flags struct {
@@ -64,6 +65,7 @@
 	Toolchain       config.Toolchain
 	Coverage        bool
 	Clippy          bool
+	EmitXrefs       bool // If true, emit rules to aid cross-referencing
 }
 
 type BaseProperties struct {
@@ -161,6 +163,9 @@
 	// Output file to be installed, may be stripped or unstripped.
 	outputFile android.OptionalPath
 
+	// Cross-reference input file
+	kytheFiles android.Paths
+
 	docTimestampFile android.OptionalPath
 
 	hideApexVariantFromMake bool
@@ -394,6 +399,10 @@
 	return false
 }
 
+func (mod *Module) XrefRustFiles() android.Paths {
+	return mod.kytheFiles
+}
+
 type Deps struct {
 	Dylibs          []string
 	Rlibs           []string
@@ -457,7 +466,7 @@
 	cfgFlags(ctx ModuleContext, flags Flags) Flags
 	featureFlags(ctx ModuleContext, flags Flags) Flags
 	compilerProps() []interface{}
-	compile(ctx ModuleContext, flags Flags, deps PathDeps) android.Path
+	compile(ctx ModuleContext, flags Flags, deps PathDeps) buildOutput
 	compilerDeps(ctx DepsContext, deps Deps) Deps
 	crateName() string
 	rustdoc(ctx ModuleContext, flags Flags, deps PathDeps) android.OptionalPath
@@ -493,6 +502,10 @@
 	exportLinkObjects(...string)
 }
 
+type xref interface {
+	XrefRustFiles() android.Paths
+}
+
 type flagExporter struct {
 	linkDirs    []string
 	linkObjects []string
@@ -904,11 +917,14 @@
 
 	if mod.compiler != nil && !mod.compiler.Disabled() {
 		mod.compiler.initialize(ctx)
-		outputFile := mod.compiler.compile(ctx, flags, deps)
+		buildOutput := mod.compiler.compile(ctx, flags, deps)
 		if ctx.Failed() {
 			return
 		}
-		mod.outputFile = android.OptionalPathForPath(outputFile)
+		mod.outputFile = android.OptionalPathForPath(buildOutput.outputFile)
+		if buildOutput.kytheFile != nil {
+			mod.kytheFiles = append(mod.kytheFiles, buildOutput.kytheFile)
+		}
 		bloaty.MeasureSizeForPaths(ctx, mod.compiler.strippedOutputFilePath(), android.OptionalPathForPath(mod.compiler.unstrippedOutputFilePath()))
 
 		mod.docTimestampFile = mod.compiler.rustdoc(ctx, flags, deps)
@@ -1618,6 +1634,25 @@
 	return "", false
 }
 
+func kytheExtractRustFactory() android.Singleton {
+	return &kytheExtractRustSingleton{}
+}
+
+type kytheExtractRustSingleton struct {
+}
+
+func (k kytheExtractRustSingleton) GenerateBuildActions(ctx android.SingletonContext) {
+	var xrefTargets android.Paths
+	ctx.VisitAllModules(func(module android.Module) {
+		if rustModule, ok := module.(xref); ok {
+			xrefTargets = append(xrefTargets, rustModule.XrefRustFiles()...)
+		}
+	})
+	if len(xrefTargets) > 0 {
+		ctx.Phony("xref_rust", xrefTargets...)
+	}
+}
+
 var Bool = proptools.Bool
 var BoolDefault = proptools.BoolDefault
 var String = proptools.String
diff --git a/rust/snapshot_prebuilt.go b/rust/snapshot_prebuilt.go
index dfbc1d1..2f79cc5 100644
--- a/rust/snapshot_prebuilt.go
+++ b/rust/snapshot_prebuilt.go
@@ -69,7 +69,7 @@
 	return module, prebuilt
 }
 
-func (library *snapshotLibraryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) android.Path {
+func (library *snapshotLibraryDecorator) compile(ctx ModuleContext, flags Flags, deps PathDeps) buildOutput {
 	var variant string
 	if library.static() {
 		variant = cc.SnapshotStaticSuffix
@@ -85,11 +85,11 @@
 	}
 
 	if !library.MatchesWithDevice(ctx.DeviceConfig()) {
-		return nil
+		return buildOutput{}
 	}
 	outputFile := android.PathForModuleSrc(ctx, *library.properties.Src)
 	library.unstrippedOutputFile = outputFile
-	return outputFile
+	return buildOutput{outputFile: outputFile}
 }
 
 func (library *snapshotLibraryDecorator) rustdoc(ctx ModuleContext, flags Flags, deps PathDeps) android.OptionalPath {
diff --git a/rust/testing.go b/rust/testing.go
index cb98bed..4796f69 100644
--- a/rust/testing.go
+++ b/rust/testing.go
@@ -194,6 +194,7 @@
 		ctx.BottomUp("rust_begin", BeginMutator).Parallel()
 	})
 	ctx.RegisterSingletonType("rust_project_generator", rustProjectGeneratorSingleton)
+	ctx.RegisterSingletonType("kythe_rust_extract", kytheExtractRustFactory)
 	ctx.PostDepsMutators(func(ctx android.RegisterMutatorsContext) {
 		ctx.BottomUp("rust_sanitizers", rustSanitizerRuntimeMutator).Parallel()
 	})
diff --git a/sdk/cc_sdk_test.go b/sdk/cc_sdk_test.go
index cd63dac..571d214 100644
--- a/sdk/cc_sdk_test.go
+++ b/sdk/cc_sdk_test.go
@@ -193,114 +193,6 @@
 `))
 }
 
-func TestBasicSdkWithCc(t *testing.T) {
-	result := testSdkWithCc(t, `
-		sdk {
-			name: "mysdk",
-			native_shared_libs: ["sdkmember"],
-		}
-
-		cc_library_shared {
-			name: "sdkmember",
-			system_shared_libs: [],
-			stl: "none",
-			apex_available: ["mysdkapex"],
-		}
-
-		sdk_snapshot {
-			name: "mysdk@1",
-			native_shared_libs: ["sdkmember_mysdk@1"],
-		}
-
-		sdk_snapshot {
-			name: "mysdk@2",
-			native_shared_libs: ["sdkmember_mysdk@2"],
-		}
-
-		cc_prebuilt_library_shared {
-			name: "sdkmember",
-			srcs: ["libfoo.so"],
-			prefer: false,
-			system_shared_libs: [],
-			stl: "none",
-		}
-
-		cc_prebuilt_library_shared {
-			name: "sdkmember_mysdk@1",
-			sdk_member_name: "sdkmember",
-			srcs: ["libfoo.so"],
-			system_shared_libs: [],
-			stl: "none",
-			// TODO: remove //apex_available:platform
-			apex_available: [
-				"//apex_available:platform",
-				"myapex",
-			],
-		}
-
-		cc_prebuilt_library_shared {
-			name: "sdkmember_mysdk@2",
-			sdk_member_name: "sdkmember",
-			srcs: ["libfoo.so"],
-			system_shared_libs: [],
-			stl: "none",
-			// TODO: remove //apex_available:platform
-			apex_available: [
-				"//apex_available:platform",
-				"myapex2",
-			],
-		}
-
-		cc_library_shared {
-			name: "mycpplib",
-			srcs: ["Test.cpp"],
-			shared_libs: ["sdkmember"],
-			system_shared_libs: [],
-			stl: "none",
-			apex_available: [
-				"myapex",
-				"myapex2",
-			],
-		}
-
-		apex {
-			name: "myapex",
-			native_shared_libs: ["mycpplib"],
-			uses_sdks: ["mysdk@1"],
-			key: "myapex.key",
-			certificate: ":myapex.cert",
-			updatable: false,
-		}
-
-		apex {
-			name: "myapex2",
-			native_shared_libs: ["mycpplib"],
-			uses_sdks: ["mysdk@2"],
-			key: "myapex.key",
-			certificate: ":myapex.cert",
-			updatable: false,
-		}
-
-		apex {
-			name: "mysdkapex",
-			native_shared_libs: ["sdkmember"],
-			key: "myapex.key",
-			certificate: ":myapex.cert",
-			updatable: false,
-		}
-	`)
-
-	sdkMemberV1 := result.ModuleForTests("sdkmember_mysdk@1", "android_arm64_armv8-a_shared_apex10000_mysdk_1").Rule("toc").Output
-	sdkMemberV2 := result.ModuleForTests("sdkmember_mysdk@2", "android_arm64_armv8-a_shared_apex10000_mysdk_2").Rule("toc").Output
-
-	cpplibForMyApex := result.ModuleForTests("mycpplib", "android_arm64_armv8-a_shared_apex10000_mysdk_1")
-	cpplibForMyApex2 := result.ModuleForTests("mycpplib", "android_arm64_armv8-a_shared_apex10000_mysdk_2")
-
-	// Depending on the uses_sdks value, different libs are linked
-	ensureListContains(t, pathsToStrings(cpplibForMyApex.Rule("ld").Implicits), sdkMemberV1.String())
-	ensureListContains(t, pathsToStrings(cpplibForMyApex2.Rule("ld").Implicits), sdkMemberV2.String())
-}
-
 // Make sure the sdk can use host specific cc libraries static/shared and both.
 func TestHostSdkWithCc(t *testing.T) {
 	testSdkWithCc(t, `
@@ -2835,11 +2727,6 @@
 		}
 	`)
 
-	// Mixing the snapshot with the source (irrespective of which one is preferred) causes a problem
-	// due to missing variants.
-	// TODO(b/183204176): Remove this and fix the cause.
-	snapshotWithSourceErrorHandler := android.FixtureExpectsAtLeastOneErrorMatchingPattern(`\QReplaceDependencies could not find identical variant {os:android,image:,arch:arm64_armv8-a,sdk:,link:shared,version:} for module mynativelib\E`)
-
 	CheckSnapshot(t, result, "mysdk", "",
 		checkUnversionedAndroidBpContents(`
 // This is auto-generated. DO NOT EDIT.
@@ -2866,7 +2753,5 @@
 arm64/include/Arm64Test.h -> arm64/include/arm64/include/Arm64Test.h
 .intermediates/mynativelib/android_arm_armv7-a-neon_shared/mynativelib.so -> arm/lib/mynativelib.so
 `),
-		snapshotTestErrorHandler(checkSnapshotWithSourcePreferred, snapshotWithSourceErrorHandler),
-		snapshotTestErrorHandler(checkSnapshotPreferredWithSource, snapshotWithSourceErrorHandler),
 	)
 }
diff --git a/sdk/java_sdk_test.go b/sdk/java_sdk_test.go
index f0d3b35..a99fa1f 100644
--- a/sdk/java_sdk_test.go
+++ b/sdk/java_sdk_test.go
@@ -71,90 +71,6 @@
 	)
 }
 
-func TestBasicSdkWithJavaLibrary(t *testing.T) {
-	result := android.GroupFixturePreparers(
-		prepareForSdkTestWithJava,
-		prepareForSdkTestWithApex,
-	).RunTestWithBp(t, `
-		sdk {
-			name: "mysdk",
-			java_header_libs: ["sdkmember"],
-		}
-
-		sdk_snapshot {
-			name: "mysdk@1",
-			java_header_libs: ["sdkmember_mysdk@1"],
-		}
-
-		sdk_snapshot {
-			name: "mysdk@2",
-			java_header_libs: ["sdkmember_mysdk@2"],
-		}
-
-		java_library {
-			name: "sdkmember",
-			srcs: ["Test.java"],
-			system_modules: "none",
-			sdk_version: "none",
-			host_supported: true,
-		}
-
-		java_import {
-			name: "sdkmember_mysdk@1",
-			sdk_member_name: "sdkmember",
-			host_supported: true,
-		}
-
-		java_import {
-			name: "sdkmember_mysdk@2",
-			sdk_member_name: "sdkmember",
-			host_supported: true,
-		}
-
-		java_library {
-			name: "myjavalib",
-			srcs: ["Test.java"],
-			libs: ["sdkmember"],
-			system_modules: "none",
-			sdk_version: "none",
-			compile_dex: true,
-			host_supported: true,
-			apex_available: [
-				"myapex",
-				"myapex2",
-			],
-		}
-
-		apex {
-			name: "myapex",
-			java_libs: ["myjavalib"],
-			uses_sdks: ["mysdk@1"],
-			key: "myapex.key",
-			certificate: ":myapex.cert",
-			updatable: false,
-		}
-
-		apex {
-			name: "myapex2",
-			java_libs: ["myjavalib"],
-			uses_sdks: ["mysdk@2"],
-			key: "myapex.key",
-			certificate: ":myapex.cert",
-			updatable: false,
-		}
-	`)
-
-	sdkMemberV1 := result.ModuleForTests("sdkmember_mysdk@1", "android_common").Rule("combineJar").Output
-	sdkMemberV2 := result.ModuleForTests("sdkmember_mysdk@2", "android_common").Rule("combineJar").Output
-
-	javalibForMyApex := result.ModuleForTests("myjavalib", "android_common_apex10000_mysdk_1")
-	javalibForMyApex2 := result.ModuleForTests("myjavalib", "android_common_apex10000_mysdk_2")
-
-	// Depending on the uses_sdks value, different libs are linked
-	ensureListContains(t, pathsToStrings(javalibForMyApex.Rule("javac").Implicits), sdkMemberV1.String())
-	ensureListContains(t, pathsToStrings(javalibForMyApex2.Rule("javac").Implicits), sdkMemberV2.String())
-}
-
 func TestSnapshotWithJavaHeaderLibrary(t *testing.T) {
 	result := android.GroupFixturePreparers(
 		prepareForSdkTestWithJava,
diff --git a/sdk/sdk.go b/sdk/sdk.go
index 84c9a96..c8c7b79 100644
--- a/sdk/sdk.go
+++ b/sdk/sdk.go
@@ -39,7 +39,6 @@
 	ctx.RegisterModuleType("sdk", SdkModuleFactory)
 	ctx.RegisterModuleType("sdk_snapshot", SnapshotModuleFactory)
 	ctx.PreDepsMutators(RegisterPreDepsMutators)
-	ctx.PostDepsMutators(RegisterPostDepsMutators)
 }
 
 type sdk struct {
@@ -278,20 +277,6 @@
 	ctx.BottomUp("SdkMemberInterVersion", memberInterVersionMutator).Parallel()
 }
 
-// RegisterPostDepsMutators registers post-deps mutators to support modules implementing SdkAware
-// interface and the sdk module type. This function has been made public to be called by tests
-// outside of the sdk package
-func RegisterPostDepsMutators(ctx android.RegisterMutatorsContext) {
-	// These must run AFTER apexMutator. Note that the apex package is imported even though there is
-	// no direct dependency to the package here. sdkDepsMutator sets the SDK requirements from an
-	// APEX to its dependents. Since different versions of the same SDK can be used by different
-	// APEXes, the apex and its dependents (which includes the dependencies to the sdk members)
-	// should have been mutated for the apex before the SDK requirements are set.
-	ctx.TopDown("SdkDepsMutator", sdkDepsMutator).Parallel()
-	ctx.BottomUp("SdkDepsReplaceMutator", sdkDepsReplaceMutator).Parallel()
-	ctx.TopDown("SdkRequirementCheck", sdkRequirementsMutator).Parallel()
-}
-
 type dependencyTag struct {
 	blueprint.BaseDependencyTag
 }
@@ -413,103 +398,4 @@
 type sdkAndApexModule interface {
 	android.Module
 	android.DepIsInSameApex
-	android.RequiredSdks
-}
-
-// Step 4: transitively ripple down the SDK requirements from the root modules like APEX to its
-// descendants
-func sdkDepsMutator(mctx android.TopDownMutatorContext) {
-	if parent, ok := mctx.Module().(sdkAndApexModule); ok {
-		// Module types for Mainline modules (e.g. APEX) are expected to implement RequiredSdks()
-		// by reading its own properties like `uses_sdks`.
-		requiredSdks := parent.RequiredSdks()
-		if len(requiredSdks) > 0 {
-			mctx.VisitDirectDeps(func(m android.Module) {
-				// Only propagate required sdks from the apex onto its contents.
-				if dep, ok := m.(android.SdkAware); ok && android.IsDepInSameApex(mctx, parent, dep) {
-					dep.BuildWithSdks(requiredSdks)
-				}
-			})
-		}
-	}
-}
-
-// Step 5: if libfoo.mysdk.11 is in the context where version 11 of mysdk is requested, the
-// versioned module is used instead of the un-versioned (in-development) module libfoo
-func sdkDepsReplaceMutator(mctx android.BottomUpMutatorContext) {
-	if versionedSdkMember, ok := mctx.Module().(android.SdkAware); ok && versionedSdkMember.IsInAnySdk() && versionedSdkMember.IsVersioned() {
-		if sdk := versionedSdkMember.ContainingSdk(); !sdk.Unversioned() {
-			// Only replace dependencies to <sdkmember> with <sdkmember@required-version>
-			// if the depending module requires it. e.g.
-			//      foo -> sdkmember
-			// will be transformed to:
-			//      foo -> sdkmember@1
-			// if and only if foo is a member of an APEX that requires version 1 of the
-			// sdk containing sdkmember.
-			memberName := versionedSdkMember.MemberName()
-
-			// Convert a panic into a normal error to allow it to be more easily tested for. This is a
-			// temporary workaround, once http://b/183204176 has been fixed this can be removed.
-			// TODO(b/183204176): Remove this after fixing.
-			defer func() {
-				if r := recover(); r != nil {
-					mctx.ModuleErrorf("sdkDepsReplaceMutator %s", r)
-				}
-			}()
-
-			// Replace dependencies on sdkmember with a dependency on the current module which
-			// is a versioned prebuilt of the sdkmember if required.
-			mctx.ReplaceDependenciesIf(memberName, func(from blueprint.Module, tag blueprint.DependencyTag, to blueprint.Module) bool {
-				// from - foo
-				// to - sdkmember
-				replace := false
-				if parent, ok := from.(android.RequiredSdks); ok {
-					replace = parent.RequiredSdks().Contains(sdk)
-				}
-				return replace
-			})
-		}
-	}
-}
-
-// Step 6: ensure that the dependencies outside of the APEX are all from the required SDKs
-func sdkRequirementsMutator(mctx android.TopDownMutatorContext) {
-	if m, ok := mctx.Module().(sdkAndApexModule); ok {
-		requiredSdks := m.RequiredSdks()
-		if len(requiredSdks) == 0 {
-			return
-		}
-		mctx.VisitDirectDeps(func(dep android.Module) {
-			tag := mctx.OtherModuleDependencyTag(dep)
-			if tag == android.DefaultsDepTag {
-				// dependency to defaults is always okay
-				return
-			}
-
-			// Ignore the dependency from the unversioned member to any versioned members as an
-			// apex that depends on the unversioned member will not also be depending on a versioned
-			// member.
-			if _, ok := tag.(sdkMemberVersionedDepTag); ok {
-				return
-			}
-
-			// If the dep is outside of the APEX, but is not in any of the required SDKs, we know that the
-			// dep is a violation.
-			if sa, ok := dep.(android.SdkAware); ok {
-				// It is not an error if a dependency that is excluded from the apex due to the tag is not
-				// in one of the required SDKs. That is because all of the existing tags that implement it
-				// do not depend on modules which can or should belong to an sdk_snapshot.
-				if _, ok := tag.(android.ExcludeFromApexContentsTag); ok {
-					// The tag defines a dependency that never requires the child module to be part of the
-					// same apex.
-					return
-				}
-
-				if !m.DepIsInSameApex(mctx, dep) && !requiredSdks.Contains(sa.ContainingSdk()) {
-					mctx.ModuleErrorf("depends on %q (in SDK %q) that isn't part of the required SDKs: %v",
-						sa.Name(), sa.ContainingSdk(), requiredSdks)
-				}
-			}
-		})
-	}
 }
diff --git a/sdk/sdk_test.go b/sdk/sdk_test.go
index 83294f6..40de150 100644
--- a/sdk/sdk_test.go
+++ b/sdk/sdk_test.go
@@ -37,64 +37,6 @@
 	os.Exit(m.Run())
 }
 
-func TestDepNotInRequiredSdks(t *testing.T) {
-	testSdkError(t, `module "myjavalib".*depends on "otherlib".*that isn't part of the required SDKs:.*`, `
-		sdk {
-			name: "mysdk",
-			java_header_libs: ["sdkmember"],
-		}
-
-		sdk_snapshot {
-			name: "mysdk@1",
-			java_header_libs: ["sdkmember_mysdk_1"],
-		}
-
-		java_import {
-			name: "sdkmember",
-			prefer: false,
-			host_supported: true,
-		}
-
-		java_import {
-			name: "sdkmember_mysdk_1",
-			sdk_member_name: "sdkmember",
-			host_supported: true,
-		}
-
-		java_library {
-			name: "myjavalib",
-			srcs: ["Test.java"],
-			libs: [
-				"sdkmember",
-				"otherlib",
-			],
-			system_modules: "none",
-			sdk_version: "none",
-			compile_dex: true,
-			host_supported: true,
-			apex_available: ["myapex"],
-		}
-
-		// this lib is no in mysdk
-		java_library {
-			name: "otherlib",
-			srcs: ["Test.java"],
-			system_modules: "none",
-			sdk_version: "none",
-			compile_dex: true,
-			host_supported: true,
-		}
-
-		apex {
-			name: "myapex",
-			java_libs: ["myjavalib"],
-			uses_sdks: ["mysdk@1"],
-			key: "myapex.key",
-			certificate: ":myapex.cert",
-		}
-	`)
-}
-
 // Ensure that prebuilt modules have the same effective visibility as the source
 // modules.
 func TestSnapshotVisibility(t *testing.T) {
diff --git a/ui/metrics/metrics_proto/metrics.pb.go b/ui/metrics/metrics_proto/metrics.pb.go
index 69f5689..9f9b863 100644
--- a/ui/metrics/metrics_proto/metrics.pb.go
+++ b/ui/metrics/metrics_proto/metrics.pb.go
@@ -14,7 +14,7 @@
 
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
-// 	protoc-gen-go v1.27.1
+// 	protoc-gen-go v1.28.0
 // 	protoc        v3.9.1
 // source: metrics.proto
 
@@ -954,9 +954,9 @@
 	sizeCache     protoimpl.SizeCache
 	unknownFields protoimpl.UnknownFields
 
-	// The build system, eg. Soong or Make.
+	// The build system, e.g. Soong or Make.
 	BuildSystem *ModuleTypeInfo_BuildSystem `protobuf:"varint,1,opt,name=build_system,json=buildSystem,enum=soong_build_metrics.ModuleTypeInfo_BuildSystem,def=0" json:"build_system,omitempty"`
-	// The module type, eg. java_library, cc_binary, and etc.
+	// The module type, e.g. java_library, cc_binary, and etc.
 	ModuleType *string `protobuf:"bytes,2,opt,name=module_type,json=moduleType" json:"module_type,omitempty"`
 	// The number of logical modules.
 	NumOfModules *uint32 `protobuf:"varint,3,opt,name=num_of_modules,json=numOfModules" json:"num_of_modules,omitempty"`
@@ -1142,6 +1142,8 @@
 	MaxHeapSize *uint64 `protobuf:"varint,5,opt,name=max_heap_size,json=maxHeapSize" json:"max_heap_size,omitempty"`
 	// Runtime metrics for soong_build execution.
 	Events []*PerfInfo `protobuf:"bytes,6,rep,name=events" json:"events,omitempty"`
+	// Mixed Builds information
+	MixedBuildsInfo *MixedBuildsInfo `protobuf:"bytes,7,opt,name=mixed_builds_info,json=mixedBuildsInfo" json:"mixed_builds_info,omitempty"`
 }
 
 func (x *SoongBuildMetrics) Reset() {
@@ -1218,6 +1220,13 @@
 	return nil
 }
 
+func (x *SoongBuildMetrics) GetMixedBuildsInfo() *MixedBuildsInfo {
+	if x != nil {
+		return x.MixedBuildsInfo
+	}
+	return nil
+}
+
 type ExpConfigFetcher struct {
 	state         protoimpl.MessageState
 	sizeCache     protoimpl.SizeCache
@@ -1287,6 +1296,63 @@
 	return 0
 }
 
+type MixedBuildsInfo struct {
+	state         protoimpl.MessageState
+	sizeCache     protoimpl.SizeCache
+	unknownFields protoimpl.UnknownFields
+
+	// Modules that are enabled for Mixed Builds.
+	MixedBuildEnabledModules []string `protobuf:"bytes,1,rep,name=mixed_build_enabled_modules,json=mixedBuildEnabledModules" json:"mixed_build_enabled_modules,omitempty"`
+	// Modules that are not currently eligible for MixedBuilds
+	MixedBuildDisabledModules []string `protobuf:"bytes,2,rep,name=mixed_build_disabled_modules,json=mixedBuildDisabledModules" json:"mixed_build_disabled_modules,omitempty"`
+}
+
+func (x *MixedBuildsInfo) Reset() {
+	*x = MixedBuildsInfo{}
+	if protoimpl.UnsafeEnabled {
+		mi := &file_metrics_proto_msgTypes[10]
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		ms.StoreMessageInfo(mi)
+	}
+}
+
+func (x *MixedBuildsInfo) String() string {
+	return protoimpl.X.MessageStringOf(x)
+}
+
+func (*MixedBuildsInfo) ProtoMessage() {}
+
+func (x *MixedBuildsInfo) ProtoReflect() protoreflect.Message {
+	mi := &file_metrics_proto_msgTypes[10]
+	if protoimpl.UnsafeEnabled && x != nil {
+		ms := protoimpl.X.MessageStateOf(protoimpl.Pointer(x))
+		if ms.LoadMessageInfo() == nil {
+			ms.StoreMessageInfo(mi)
+		}
+		return ms
+	}
+	return mi.MessageOf(x)
+}
+
+// Deprecated: Use MixedBuildsInfo.ProtoReflect.Descriptor instead.
+func (*MixedBuildsInfo) Descriptor() ([]byte, []int) {
+	return file_metrics_proto_rawDescGZIP(), []int{10}
+}
+
+func (x *MixedBuildsInfo) GetMixedBuildEnabledModules() []string {
+	if x != nil {
+		return x.MixedBuildEnabledModules
+	}
+	return nil
+}
+
+func (x *MixedBuildsInfo) GetMixedBuildDisabledModules() []string {
+	if x != nil {
+		return x.MixedBuildDisabledModules
+	}
+	return nil
+}
+
 var File_metrics_proto protoreflect.FileDescriptor
 
 var file_metrics_proto_rawDesc = []byte{
@@ -1491,7 +1557,7 @@
 	0x2e, 0x73, 0x6f, 0x6f, 0x6e, 0x67, 0x5f, 0x62, 0x75, 0x69, 0x6c, 0x64, 0x5f, 0x6d, 0x65, 0x74,
 	0x72, 0x69, 0x63, 0x73, 0x2e, 0x43, 0x72, 0x69, 0x74, 0x69, 0x63, 0x61, 0x6c, 0x55, 0x73, 0x65,
 	0x72, 0x4a, 0x6f, 0x75, 0x72, 0x6e, 0x65, 0x79, 0x4d, 0x65, 0x74, 0x72, 0x69, 0x63, 0x73, 0x52,
-	0x04, 0x63, 0x75, 0x6a, 0x73, 0x22, 0xfa, 0x01, 0x0a, 0x11, 0x53, 0x6f, 0x6f, 0x6e, 0x67, 0x42,
+	0x04, 0x63, 0x75, 0x6a, 0x73, 0x22, 0xcc, 0x02, 0x0a, 0x11, 0x53, 0x6f, 0x6f, 0x6e, 0x67, 0x42,
 	0x75, 0x69, 0x6c, 0x64, 0x4d, 0x65, 0x74, 0x72, 0x69, 0x63, 0x73, 0x12, 0x18, 0x0a, 0x07, 0x6d,
 	0x6f, 0x64, 0x75, 0x6c, 0x65, 0x73, 0x18, 0x01, 0x20, 0x01, 0x28, 0x0d, 0x52, 0x07, 0x6d, 0x6f,
 	0x64, 0x75, 0x6c, 0x65, 0x73, 0x12, 0x1a, 0x0a, 0x08, 0x76, 0x61, 0x72, 0x69, 0x61, 0x6e, 0x74,
@@ -1507,22 +1573,36 @@
 	0x76, 0x65, 0x6e, 0x74, 0x73, 0x18, 0x06, 0x20, 0x03, 0x28, 0x0b, 0x32, 0x1d, 0x2e, 0x73, 0x6f,
 	0x6f, 0x6e, 0x67, 0x5f, 0x62, 0x75, 0x69, 0x6c, 0x64, 0x5f, 0x6d, 0x65, 0x74, 0x72, 0x69, 0x63,
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+	0x65, 0x73, 0x18, 0x02, 0x20, 0x03, 0x28, 0x09, 0x52, 0x19, 0x6d, 0x69, 0x78, 0x65, 0x64, 0x42,
+	0x75, 0x69, 0x6c, 0x64, 0x44, 0x69, 0x73, 0x61, 0x62, 0x6c, 0x65, 0x64, 0x4d, 0x6f, 0x64, 0x75,
+	0x6c, 0x65, 0x73, 0x42, 0x28, 0x5a, 0x26, 0x61, 0x6e, 0x64, 0x72, 0x6f, 0x69, 0x64, 0x2f, 0x73,
+	0x6f, 0x6f, 0x6e, 0x67, 0x2f, 0x75, 0x69, 0x2f, 0x6d, 0x65, 0x74, 0x72, 0x69, 0x63, 0x73, 0x2f,
+	0x6d, 0x65, 0x74, 0x72, 0x69, 0x63, 0x73, 0x5f, 0x70, 0x72, 0x6f, 0x74, 0x6f,
 }
 
 var (
@@ -1538,7 +1618,7 @@
 }
 
 var file_metrics_proto_enumTypes = make([]protoimpl.EnumInfo, 4)
-var file_metrics_proto_msgTypes = make([]protoimpl.MessageInfo, 10)
+var file_metrics_proto_msgTypes = make([]protoimpl.MessageInfo, 11)
 var file_metrics_proto_goTypes = []interface{}{
 	(MetricsBase_BuildVariant)(0),       // 0: soong_build_metrics.MetricsBase.BuildVariant
 	(MetricsBase_Arch)(0),               // 1: soong_build_metrics.MetricsBase.Arch
@@ -1554,6 +1634,7 @@
 	(*CriticalUserJourneysMetrics)(nil), // 11: soong_build_metrics.CriticalUserJourneysMetrics
 	(*SoongBuildMetrics)(nil),           // 12: soong_build_metrics.SoongBuildMetrics
 	(*ExpConfigFetcher)(nil),            // 13: soong_build_metrics.ExpConfigFetcher
+	(*MixedBuildsInfo)(nil),             // 14: soong_build_metrics.MixedBuildsInfo
 }
 var file_metrics_proto_depIdxs = []int32{
 	0,  // 0: soong_build_metrics.MetricsBase.target_build_variant:type_name -> soong_build_metrics.MetricsBase.BuildVariant
@@ -1575,12 +1656,13 @@
 	4,  // 16: soong_build_metrics.CriticalUserJourneyMetrics.metrics:type_name -> soong_build_metrics.MetricsBase
 	10, // 17: soong_build_metrics.CriticalUserJourneysMetrics.cujs:type_name -> soong_build_metrics.CriticalUserJourneyMetrics
 	7,  // 18: soong_build_metrics.SoongBuildMetrics.events:type_name -> soong_build_metrics.PerfInfo
-	3,  // 19: soong_build_metrics.ExpConfigFetcher.status:type_name -> soong_build_metrics.ExpConfigFetcher.ConfigStatus
-	20, // [20:20] is the sub-list for method output_type
-	20, // [20:20] is the sub-list for method input_type
-	20, // [20:20] is the sub-list for extension type_name
-	20, // [20:20] is the sub-list for extension extendee
-	0,  // [0:20] is the sub-list for field type_name
+	14, // 19: soong_build_metrics.SoongBuildMetrics.mixed_builds_info:type_name -> soong_build_metrics.MixedBuildsInfo
+	3,  // 20: soong_build_metrics.ExpConfigFetcher.status:type_name -> soong_build_metrics.ExpConfigFetcher.ConfigStatus
+	21, // [21:21] is the sub-list for method output_type
+	21, // [21:21] is the sub-list for method input_type
+	21, // [21:21] is the sub-list for extension type_name
+	21, // [21:21] is the sub-list for extension extendee
+	0,  // [0:21] is the sub-list for field type_name
 }
 
 func init() { file_metrics_proto_init() }
@@ -1709,6 +1791,18 @@
 				return nil
 			}
 		}
+		file_metrics_proto_msgTypes[10].Exporter = func(v interface{}, i int) interface{} {
+			switch v := v.(*MixedBuildsInfo); i {
+			case 0:
+				return &v.state
+			case 1:
+				return &v.sizeCache
+			case 2:
+				return &v.unknownFields
+			default:
+				return nil
+			}
+		}
 	}
 	type x struct{}
 	out := protoimpl.TypeBuilder{
@@ -1716,7 +1810,7 @@
 			GoPackagePath: reflect.TypeOf(x{}).PkgPath(),
 			RawDescriptor: file_metrics_proto_rawDesc,
 			NumEnums:      4,
-			NumMessages:   10,
+			NumMessages:   11,
 			NumExtensions: 0,
 			NumServices:   0,
 		},
diff --git a/ui/metrics/metrics_proto/metrics.proto b/ui/metrics/metrics_proto/metrics.proto
index 814eb67..51dd523 100644
--- a/ui/metrics/metrics_proto/metrics.proto
+++ b/ui/metrics/metrics_proto/metrics.proto
@@ -200,10 +200,10 @@
     SOONG = 1;
     MAKE = 2;
   }
-  // The build system, eg. Soong or Make.
+  // The build system, e.g. Soong or Make.
   optional BuildSystem build_system = 1 [default = UNKNOWN];
 
-  // The module type, eg. java_library, cc_binary, and etc.
+  // The module type, e.g. java_library, cc_binary, and etc.
   optional string module_type = 2;
 
   // The number of logical modules.
@@ -241,6 +241,9 @@
 
   // Runtime metrics for soong_build execution.
   repeated PerfInfo events = 6;
+
+  // Mixed Builds information
+  optional MixedBuildsInfo mixed_builds_info = 7;
 }
 
 message ExpConfigFetcher {
@@ -261,3 +264,25 @@
   // Time, in microseconds, taken by the expconfigfetcher
   optional uint64 micros = 3;
 }
+
+message MixedBuildsInfo{
+  // Modules may be listed below as both enabled for Mixed Builds
+  // and disabled for Mixed Builds. This implies that some variants
+  // of the module are handled by Bazel in a Mixed Build, and other
+  // variants of the same module are handled by Soong.
+
+  // Modules that are enabled for Mixed Builds.
+  repeated string mixed_build_enabled_modules = 1;
+
+  // Modules that are not currently eligible to be handled
+  // by Bazel in a Mixed Build.
+  // Note that not all modules exempt from Bazel handling are
+  // listed. This list includes only modules which are of a
+  // Mixed-Build supported module type but are nevertheless not
+  // handled by Bazel. This may occur due to being present in
+  // the mixed build denylist, or as part of an unsupported
+  // mixed build variant type such as Windows.
+
+  // Modules that are not enabled for MixedBuilds
+  repeated string mixed_build_disabled_modules = 2;
+}