diff --git a/cc/cc_test.go b/cc/cc_test.go
index 465283d..e4dfc97 100644
--- a/cc/cc_test.go
+++ b/cc/cc_test.go
@@ -244,6 +244,120 @@
 	}
 }
 
+func checkInstallPartition(t *testing.T, ctx *android.TestContext, name, variant, expected string) {
+	mod := ctx.ModuleForTests(name, variant).Module().(*Module)
+	partitionDefined := false
+	checkPartition := func(specific bool, partition string) {
+		if specific {
+			if expected != partition && !partitionDefined {
+				// The variant is installed to the 'partition'
+				t.Errorf("%s variant of %q must not be installed to %s partition", variant, name, partition)
+			}
+			partitionDefined = true
+		} else {
+			// The variant is not installed to the 'partition'
+			if expected == partition {
+				t.Errorf("%s variant of %q must be installed to %s partition", variant, name, partition)
+			}
+		}
+	}
+	socSpecific := func(m *Module) bool {
+		return m.SocSpecific() || m.socSpecificModuleContext()
+	}
+	deviceSpecific := func(m *Module) bool {
+		return m.DeviceSpecific() || m.deviceSpecificModuleContext()
+	}
+	productSpecific := func(m *Module) bool {
+		return m.ProductSpecific() || m.productSpecificModuleContext()
+	}
+	systemExtSpecific := func(m *Module) bool {
+		return m.SystemExtSpecific()
+	}
+	checkPartition(socSpecific(mod), "vendor")
+	checkPartition(deviceSpecific(mod), "odm")
+	checkPartition(productSpecific(mod), "product")
+	checkPartition(systemExtSpecific(mod), "system_ext")
+	if !partitionDefined && expected != "system" {
+		t.Errorf("%s variant of %q is expected to be installed to %s partition,"+
+			" but installed to system partition", variant, name, expected)
+	}
+}
+
+func TestInstallPartition(t *testing.T) {
+	t.Helper()
+	ctx := prepareForCcTest.RunTestWithBp(t, `
+		cc_library {
+			name: "libsystem",
+		}
+		cc_library {
+			name: "libsystem_ext",
+			system_ext_specific: true,
+		}
+		cc_library {
+			name: "libproduct",
+			product_specific: true,
+		}
+		cc_library {
+			name: "libvendor",
+			vendor: true,
+		}
+		cc_library {
+			name: "libodm",
+			device_specific: true,
+		}
+		cc_library {
+			name: "liball_available",
+			vendor_available: true,
+			product_available: true,
+		}
+		cc_library {
+			name: "libsystem_ext_all_available",
+			system_ext_specific: true,
+			vendor_available: true,
+			product_available: true,
+		}
+		cc_library {
+			name: "liball_available_odm",
+			odm_available: true,
+			product_available: true,
+		}
+		cc_library {
+			name: "libproduct_vendoravailable",
+			product_specific: true,
+			vendor_available: true,
+		}
+		cc_library {
+			name: "libproduct_odmavailable",
+			product_specific: true,
+			odm_available: true,
+		}
+	`).TestContext
+
+	checkInstallPartition(t, ctx, "libsystem", coreVariant, "system")
+	checkInstallPartition(t, ctx, "libsystem_ext", coreVariant, "system_ext")
+	checkInstallPartition(t, ctx, "libproduct", productVariant, "product")
+	checkInstallPartition(t, ctx, "libvendor", vendorVariant, "vendor")
+	checkInstallPartition(t, ctx, "libodm", vendorVariant, "odm")
+
+	checkInstallPartition(t, ctx, "liball_available", coreVariant, "system")
+	checkInstallPartition(t, ctx, "liball_available", productVariant, "product")
+	checkInstallPartition(t, ctx, "liball_available", vendorVariant, "vendor")
+
+	checkInstallPartition(t, ctx, "libsystem_ext_all_available", coreVariant, "system_ext")
+	checkInstallPartition(t, ctx, "libsystem_ext_all_available", productVariant, "product")
+	checkInstallPartition(t, ctx, "libsystem_ext_all_available", vendorVariant, "vendor")
+
+	checkInstallPartition(t, ctx, "liball_available_odm", coreVariant, "system")
+	checkInstallPartition(t, ctx, "liball_available_odm", productVariant, "product")
+	checkInstallPartition(t, ctx, "liball_available_odm", vendorVariant, "odm")
+
+	checkInstallPartition(t, ctx, "libproduct_vendoravailable", productVariant, "product")
+	checkInstallPartition(t, ctx, "libproduct_vendoravailable", vendorVariant, "vendor")
+
+	checkInstallPartition(t, ctx, "libproduct_odmavailable", productVariant, "product")
+	checkInstallPartition(t, ctx, "libproduct_odmavailable", vendorVariant, "odm")
+}
+
 func checkVndkModule(t *testing.T, ctx *android.TestContext, name, subDir string,
 	isVndkSp bool, extends string, variant string) {
 
diff --git a/cc/gen.go b/cc/gen.go
index 83c019c..b152e02 100644
--- a/cc/gen.go
+++ b/cc/gen.go
@@ -111,9 +111,7 @@
 	return ret
 }
 
-func genAidl(ctx android.ModuleContext, rule *android.RuleBuilder, aidlFile android.Path,
-	outFile, depFile android.ModuleGenPath, aidlFlags string) android.Paths {
-
+func genAidl(ctx android.ModuleContext, rule *android.RuleBuilder, aidlFile android.Path, aidlFlags string) (cppFile android.OutputPath, headerFiles android.Paths) {
 	aidlPackage := strings.TrimSuffix(aidlFile.Rel(), aidlFile.Base())
 	baseName := strings.TrimSuffix(aidlFile.Base(), aidlFile.Ext())
 	shortName := baseName
@@ -126,6 +124,8 @@
 	}
 
 	outDir := android.PathForModuleGen(ctx, "aidl")
+	cppFile = outDir.Join(ctx, aidlPackage, baseName+".cpp")
+	depFile := outDir.Join(ctx, aidlPackage, baseName+".cpp.d")
 	headerI := outDir.Join(ctx, aidlPackage, baseName+".h")
 	headerBn := outDir.Join(ctx, aidlPackage, "Bn"+shortName+".h")
 	headerBp := outDir.Join(ctx, aidlPackage, "Bp"+shortName+".h")
@@ -142,14 +142,14 @@
 		Flag(aidlFlags).
 		Input(aidlFile).
 		OutputDir().
-		Output(outFile).
+		Output(cppFile).
 		ImplicitOutputs(android.WritablePaths{
 			headerI,
 			headerBn,
 			headerBp,
 		})
 
-	return android.Paths{
+	return cppFile, android.Paths{
 		headerI,
 		headerBn,
 		headerBp,
@@ -293,10 +293,9 @@
 				aidlRule = android.NewRuleBuilder(pctx, ctx).Sbox(android.PathForModuleGen(ctx, "aidl"),
 					android.PathForModuleGen(ctx, "aidl.sbox.textproto"))
 			}
-			cppFile := android.GenPathWithExt(ctx, "aidl", srcFile, "cpp")
-			depFile := android.GenPathWithExt(ctx, "aidl", srcFile, "cpp.d")
+			cppFile, aidlHeaders := genAidl(ctx, aidlRule, srcFile, buildFlags.aidlFlags)
 			srcFiles[i] = cppFile
-			aidlHeaders := genAidl(ctx, aidlRule, srcFile, cppFile, depFile, buildFlags.aidlFlags)
+
 			info.aidlHeaders = append(info.aidlHeaders, aidlHeaders...)
 			// Use the generated headers as order only deps to ensure that they are up to date when
 			// needed.
diff --git a/cc/image.go b/cc/image.go
index afe6a0e..ca00ac9 100644
--- a/cc/image.go
+++ b/cc/image.go
@@ -49,21 +49,15 @@
 )
 
 func (ctx *moduleContext) ProductSpecific() bool {
-	// Additionally check if this module is inProduct() that means it is a "product" variant of a
-	// module. As well as product specific modules, product variants must be installed to /product.
-	return ctx.ModuleContext.ProductSpecific() || ctx.mod.InProduct()
+	return ctx.ModuleContext.ProductSpecific() || ctx.mod.productSpecificModuleContext()
 }
 
 func (ctx *moduleContext) SocSpecific() bool {
-	// Additionally check if this module is inVendor() that means it is a "vendor" variant of a
-	// module. As well as SoC specific modules, vendor variants must be installed to /vendor
-	// unless they have "odm_available: true".
-	return ctx.ModuleContext.SocSpecific() || (ctx.mod.InVendor() && !ctx.mod.VendorVariantToOdm())
+	return ctx.ModuleContext.SocSpecific() || ctx.mod.socSpecificModuleContext()
 }
 
 func (ctx *moduleContext) DeviceSpecific() bool {
-	// Some vendor variants want to be installed to /odm by setting "odm_available: true".
-	return ctx.ModuleContext.DeviceSpecific() || (ctx.mod.InVendor() && ctx.mod.VendorVariantToOdm())
+	return ctx.ModuleContext.DeviceSpecific() || ctx.mod.deviceSpecificModuleContext()
 }
 
 func (ctx *moduleContextImpl) inProduct() bool {
@@ -86,6 +80,24 @@
 	return ctx.mod.InRecovery()
 }
 
+func (c *Module) productSpecificModuleContext() bool {
+	// Additionally check if this module is inProduct() that means it is a "product" variant of a
+	// module. As well as product specific modules, product variants must be installed to /product.
+	return c.InProduct()
+}
+
+func (c *Module) socSpecificModuleContext() bool {
+	// Additionally check if this module is inVendor() that means it is a "vendor" variant of a
+	// module. As well as SoC specific modules, vendor variants must be installed to /vendor
+	// unless they have "odm_available: true".
+	return c.HasVendorVariant() && c.InVendor() && !c.VendorVariantToOdm()
+}
+
+func (c *Module) deviceSpecificModuleContext() bool {
+	// Some vendor variants want to be installed to /odm by setting "odm_available: true".
+	return c.InVendor() && c.VendorVariantToOdm()
+}
+
 // Returns true when this module is configured to have core and vendor variants.
 func (c *Module) HasVendorVariant() bool {
 	return Bool(c.VendorProperties.Vendor_available) || Bool(c.VendorProperties.Odm_available)
diff --git a/cmd/soong_build/main.go b/cmd/soong_build/main.go
index 1863ece..431d621 100644
--- a/cmd/soong_build/main.go
+++ b/cmd/soong_build/main.go
@@ -75,8 +75,8 @@
 	return ctx
 }
 
-func newConfig(srcDir string) android.Config {
-	configuration, err := android.NewConfig(srcDir, bootstrap.CmdlineBuildDir(), bootstrap.CmdlineModuleListFile())
+func newConfig(srcDir, outDir string) android.Config {
+	configuration, err := android.NewConfig(srcDir, outDir, bootstrap.CmdlineModuleListFile())
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "%s", err)
 		os.Exit(1)
@@ -127,7 +127,7 @@
 }
 
 func writeMetrics(configuration android.Config) {
-	metricsFile := filepath.Join(bootstrap.CmdlineBuildDir(), "soong_build_metrics.pb")
+	metricsFile := filepath.Join(configuration.BuildDir(), "soong_build_metrics.pb")
 	err := android.WriteMetrics(configuration, metricsFile)
 	if err != nil {
 		fmt.Fprintf(os.Stderr, "error writing soong_build metrics %s: %s", metricsFile, err)
@@ -193,7 +193,7 @@
 	usedVariablesFile := shared.JoinPath(outDir, "soong.environment.used")
 	// The top-level Blueprints file is passed as the first argument.
 	srcDir := filepath.Dir(flag.Arg(0))
-	configuration := newConfig(srcDir)
+	configuration := newConfig(srcDir, outDir)
 	extraNinjaDeps := []string{
 		configuration.ProductVariablesFileName,
 		shared.JoinPath(outDir, "soong.environment.used"),
@@ -203,10 +203,6 @@
 		configuration.SetAllowMissingDependencies()
 	}
 
-	// These two are here so that we restart a non-debugged soong_build when the
-	// user sets SOONG_DELVE the first time.
-	configuration.Getenv("SOONG_DELVE")
-	configuration.Getenv("SOONG_DELVE_PATH")
 	if shared.IsDebugging() {
 		// Add a non-existent file to the dependencies so that soong_build will rerun when the debugger is
 		// enabled even if it completed successfully.
diff --git a/filesystem/bootimg.go b/filesystem/bootimg.go
index 3dcc416..29a8a39 100644
--- a/filesystem/bootimg.go
+++ b/filesystem/bootimg.go
@@ -61,7 +61,7 @@
 	Vendor_boot *bool
 
 	// Optional kernel commandline
-	Cmdline *string
+	Cmdline *string `android:"arch_variant"`
 
 	// File that contains bootconfig parameters. This can be set only when `vendor_boot` is true
 	// and `header_version` is greater than or equal to 4.
diff --git a/java/Android.bp b/java/Android.bp
index f8ba1b6..2a4b596 100644
--- a/java/Android.bp
+++ b/java/Android.bp
@@ -32,6 +32,7 @@
         "boot_image.go",
         "boot_jars.go",
         "builder.go",
+        "classpath_fragment.go",
         "device_host_converter.go",
         "dex.go",
         "dexpreopt.go",
diff --git a/java/classpath_fragment.go b/java/classpath_fragment.go
new file mode 100644
index 0000000..adbe490
--- /dev/null
+++ b/java/classpath_fragment.go
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2021 The Android Open Source Project
+ *
+ * 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"
+)
+
+// Build rules and utilities to generate individual packages/modules/SdkExtensions/proto/classpaths.proto
+// config files based on build configuration to embed into /system and /apex on a device.
+//
+// See `derive_classpath` service that reads the configs at runtime and defines *CLASSPATH variables
+// on the device.
+
+type classpathType int
+
+const (
+	// Matches definition in packages/modules/SdkExtensions/proto/classpaths.proto
+	BOOTCLASSPATH classpathType = iota
+	DEX2OATBOOTCLASSPATH
+	SYSTEMSERVERCLASSPATH
+)
+
+func (c classpathType) String() string {
+	return [...]string{"BOOTCLASSPATH", "DEX2OATBOOTCLASSPATH", "SYSTEMSERVERCLASSPATH"}[c]
+}
+
+type classpathFragmentProperties struct {
+}
+
+// classpathFragment interface is implemented by a module that contributes jars to a *CLASSPATH
+// variables at runtime.
+type classpathFragment interface {
+	android.Module
+
+	classpathFragmentBase() *classpathFragmentBase
+}
+
+// classpathFragmentBase is meant to be embedded in any module types that implement classpathFragment;
+// such modules are expected to call initClasspathFragment().
+type classpathFragmentBase struct {
+	properties classpathFragmentProperties
+
+	classpathType classpathType
+
+	outputFilepath android.OutputPath
+}
+
+// Initializes classpathFragmentBase struct. Must be called by all modules that include classpathFragmentBase.
+func initClasspathFragment(c classpathFragment) {
+	base := c.classpathFragmentBase()
+	c.AddProperties(&base.properties)
+}
diff --git a/rust/fuzz.go b/rust/fuzz.go
index 6035e68..6b0a943 100644
--- a/rust/fuzz.go
+++ b/rust/fuzz.go
@@ -70,10 +70,12 @@
 }
 
 func (fuzzer *fuzzDecorator) compilerDeps(ctx DepsContext, deps Deps) Deps {
-	deps.StaticLibs = append(deps.StaticLibs,
-		config.LibFuzzerRuntimeLibrary(ctx.toolchain()))
-	deps.SharedLibs = append(deps.SharedLibs,
-		config.LibclangRuntimeLibrary(ctx.toolchain(), "asan"))
+	if libFuzzerRuntimeLibrary := config.LibFuzzerRuntimeLibrary(ctx.toolchain()); libFuzzerRuntimeLibrary != "" {
+		deps.StaticLibs = append(deps.StaticLibs, libFuzzerRuntimeLibrary)
+	}
+	if libclangRuntimeLibrary := config.LibclangRuntimeLibrary(ctx.toolchain(), "asan"); libclangRuntimeLibrary != "" {
+		deps.SharedLibs = append(deps.SharedLibs, libclangRuntimeLibrary)
+	}
 	deps.SharedLibs = append(deps.SharedLibs, "libc++")
 	deps.Rlibs = append(deps.Rlibs, "liblibfuzzer_sys")
 
diff --git a/tests/bootstrap_test.sh b/tests/bootstrap_test.sh
index b2f7b2b..5271f8d 100755
--- a/tests/bootstrap_test.sh
+++ b/tests/bootstrap_test.sh
@@ -295,6 +295,118 @@
   grep -q "Make it so" out/soong/build.ninja || fail "New action not present"
 }
 
+# Tests a glob in a build= statement in an Android.bp file, which is interpreted
+# during bootstrapping.
+function test_glob_during_bootstrapping() {
+  setup
+
+  mkdir -p a
+  cat > a/Android.bp <<'EOF'
+build=["foo*.bp"]
+EOF
+  cat > a/fooa.bp <<'EOF'
+bootstrap_go_package {
+  name: "picard-soong-rules",
+  pkgPath: "android/soong/picard",
+  deps: [
+    "blueprint",
+    "soong",
+    "soong-android",
+  ],
+  srcs: [
+    "picard.go",
+  ],
+  pluginFor: ["soong_build"],
+}
+EOF
+
+  cat > a/picard.go <<'EOF'
+package picard
+
+import (
+  "android/soong/android"
+  "github.com/google/blueprint"
+)
+
+var (
+  pctx = android.NewPackageContext("picard")
+)
+
+func init() {
+  android.RegisterSingletonType("picard", PicardSingleton)
+}
+
+func PicardSingleton() android.Singleton {
+  return &picardSingleton{}
+}
+
+type picardSingleton struct{}
+
+var Message = "Make it so."
+
+func (p *picardSingleton) GenerateBuildActions(ctx android.SingletonContext) {
+  picardRule := ctx.Rule(pctx, "picard",
+    blueprint.RuleParams{
+      Command: "echo " + Message + " > ${out}",
+      CommandDeps: []string{},
+      Description: "Something quotable",
+    })
+
+  outputFile := android.PathForOutput(ctx, "picard", "picard.txt")
+  var deps android.Paths
+
+  ctx.Build(pctx, android.BuildParams{
+    Rule: picardRule,
+    Output: outputFile,
+    Inputs: deps,
+  })
+}
+
+EOF
+
+  run_soong
+  local mtime1=$(stat -c "%y" out/soong/build.ninja)
+
+  grep -q "Make it so" out/soong/build.ninja || fail "Original action not present"
+
+  cat > a/foob.bp <<'EOF'
+bootstrap_go_package {
+  name: "worf-soong-rules",
+  pkgPath: "android/soong/worf",
+  deps: [
+    "blueprint",
+    "soong",
+    "soong-android",
+    "picard-soong-rules",
+  ],
+  srcs: [
+    "worf.go",
+  ],
+  pluginFor: ["soong_build"],
+}
+EOF
+
+  cat > a/worf.go <<'EOF'
+package worf
+
+import "android/soong/picard"
+
+func init() {
+   picard.Message = "Engage."
+}
+EOF
+
+  run_soong
+  local mtime2=$(stat -c "%y" out/soong/build.ninja)
+  if [[ "$mtime1" == "$mtime2" ]]; then
+    fail "Output Ninja file did not change"
+  fi
+
+  grep -q "Engage" out/soong/build.ninja || fail "New action not present"
+
+  grep -q "Make it so" out/soong/build.ninja && fail "Original action still present"
+}
+
 function test_null_build_after_docs {
   setup
   run_soong
@@ -326,5 +438,6 @@
 test_change_android_bp
 test_delete_android_bp
 test_add_file_to_soong_build
+test_glob_during_bootstrapping
 test_soong_build_rerun_iff_environment_changes
 test_dump_json_module_graph
diff --git a/ui/build/soong.go b/ui/build/soong.go
index 9afcb88..0089075 100644
--- a/ui/build/soong.go
+++ b/ui/build/soong.go
@@ -104,6 +104,11 @@
 	args.GlobFile = shared.JoinPath(config.SoongOutDir(), ".bootstrap/soong-build-globs.ninja")
 	args.GeneratingPrimaryBuilder = true
 
+	args.DelveListen = os.Getenv("SOONG_DELVE")
+	if args.DelveListen != "" {
+		args.DelvePath = shared.ResolveDelveBinary()
+	}
+
 	blueprintCtx := blueprint.NewContext()
 	blueprintCtx.SetIgnoreUnknownModuleTypes(true)
 	blueprintConfig := BlueprintConfig{
@@ -138,11 +143,6 @@
 
 	soongBuildEnv := config.Environment().Copy()
 	soongBuildEnv.Set("TOP", os.Getenv("TOP"))
-	// These two dependencies are read from bootstrap.go, but also need to be here
-	// so that soong_build can declare a dependency on them
-	soongBuildEnv.Set("SOONG_DELVE", os.Getenv("SOONG_DELVE"))
-	soongBuildEnv.Set("SOONG_DELVE_PATH", os.Getenv("SOONG_DELVE_PATH"))
-	soongBuildEnv.Set("SOONG_OUTDIR", config.SoongOutDir())
 	// For Bazel mixed builds.
 	soongBuildEnv.Set("BAZEL_PATH", "./tools/bazel")
 	soongBuildEnv.Set("BAZEL_HOME", filepath.Join(config.BazelOutDir(), "bazelhome"))
@@ -215,13 +215,6 @@
 		// This is currently how the command line to invoke soong_build finds the
 		// root of the source tree and the output root
 		ninjaEnv.Set("TOP", os.Getenv("TOP"))
-		ninjaEnv.Set("SOONG_OUTDIR", config.SoongOutDir())
-
-		// For debugging
-		if os.Getenv("SOONG_DELVE") != "" {
-			ninjaEnv.Set("SOONG_DELVE", os.Getenv("SOONG_DELVE"))
-			ninjaEnv.Set("SOONG_DELVE_PATH", shared.ResolveDelveBinary())
-		}
 
 		cmd.Environment = &ninjaEnv
 		cmd.Sandbox = soongSandbox