diff --git a/Tethering/Android.bp b/Tethering/Android.bp
index f3d6aee..3ab1ec2 100644
--- a/Tethering/Android.bp
+++ b/Tethering/Android.bp
@@ -26,6 +26,21 @@
 }
 
 java_defaults {
+    name: "TetheringExternalLibs",
+    // Libraries not including Tethering's own framework-tethering (different flavors of that one
+    // are needed depending on the build rule)
+    libs: [
+        "framework-connectivity.stubs.module_lib",
+        "framework-connectivity-t.stubs.module_lib",
+        "framework-statsd.stubs.module_lib",
+        "framework-wifi",
+        "framework-bluetooth",
+        "unsupportedappusage",
+    ],
+    defaults_visibility: ["//visibility:private"],
+}
+
+java_defaults {
     name: "TetheringAndroidLibraryDefaults",
     srcs: [
         "apishim/**/*.java",
@@ -51,14 +66,9 @@
         "netd-client",
         "tetheringstatsprotos",
     ],
+    defaults: ["TetheringExternalLibs"],
     libs: [
-        "framework-connectivity",
-        "framework-connectivity-t.stubs.module_lib",
-        "framework-statsd.stubs.module_lib",
         "framework-tethering.impl",
-        "framework-wifi",
-        "framework-bluetooth",
-        "unsupportedappusage",
     ],
     plugins: ["java_api_finder"],
     manifest: "AndroidManifestBase.xml",
@@ -148,9 +158,17 @@
     resource_dirs: [
         "res",
     ],
+    // Libs are not actually needed to build here since build rules using these defaults are just
+    // packaging the TetheringApiXLibs in APKs, but they are necessary so that R8 has the right
+    // references to optimize the code. Without these, there will be missing class warnings and code
+    // may be wrongly optimized.
+    // R8 runs after jarjar, so the framework-X libraries need to be the post-jarjar artifacts
+    // (framework-tethering.impl), if they are not just stubs, so that the name of jarjared
+    // classes match.
+    // TODO(b/229727645): ensure R8 fails the build fully if libraries are missing
+    defaults: ["TetheringExternalLibs"],
     libs: [
-        "framework-tethering",
-        "framework-wifi",
+        "framework-tethering.impl",
     ],
     jarjar_rules: "jarjar-rules.txt",
     optimize: {