diff --git a/core/java/Android.bp b/core/java/Android.bp
index fae411d..ee71a9d 100644
--- a/core/java/Android.bp
+++ b/core/java/Android.bp
@@ -19,6 +19,7 @@
     srcs: [
         "**/*.java",
         "**/*.aidl",
+        ":systemfeatures-gen-srcs",
         ":framework-nfc-non-updatable-sources",
     ],
     visibility: ["//frameworks/base"],
@@ -597,3 +598,29 @@
 }
 
 // protolog end
+
+// Whether to enable read-only system feature codegen.
+gen_readonly_feature_apis = select(release_flag("RELEASE_USE_SYSTEM_FEATURE_BUILD_FLAGS"), {
+    true: "true",
+    false: "false",
+    default: "false",
+})
+
+// Generates com.android.internal.pm.RoSystemFeatures, optionally compiling in
+// details about fixed system features defined by build flags. When disabled,
+// the APIs are simply passthrough stubs with no meaningful side effects.
+genrule {
+    name: "systemfeatures-gen-srcs",
+    cmd: "$(location systemfeatures-gen-tool) com.android.internal.pm.RoSystemFeatures " +
+        // --readonly=false (default) makes the codegen an effective no-op passthrough API.
+        " --readonly=" + gen_readonly_feature_apis +
+        // For now, only export "android.hardware.type.*" system features APIs.
+        // TODO(b/203143243): Use an intermediate soong var that aggregates all declared
+        // RELEASE_SYSTEM_FEATURE_* declarations into a single arg.
+        " --feature-apis=AUTOMOTIVE,WATCH,TELEVISION,EMBEDDED,PC" +
+        " > $(out)",
+    out: [
+        "RoSystemFeatures.java",
+    ],
+    tools: ["systemfeatures-gen-tool"],
+}
diff --git a/services/core/java/com/android/server/SystemConfig.java b/services/core/java/com/android/server/SystemConfig.java
index d80e40c..8b619a4 100644
--- a/services/core/java/com/android/server/SystemConfig.java
+++ b/services/core/java/com/android/server/SystemConfig.java
@@ -46,6 +46,7 @@
 import android.util.Xml;
 
 import com.android.internal.annotations.VisibleForTesting;
+import com.android.internal.pm.RoSystemFeatures;
 import com.android.internal.util.XmlUtils;
 import com.android.modules.utils.build.UnboundedSdkLevel;
 import com.android.server.pm.permission.PermissionAllowlist;
@@ -212,6 +213,30 @@
         }
     }
 
+    /**
+     * Utility class for testing interaction with compile-time defined system features.
+     * @hide
+    */
+    @VisibleForTesting
+    public static class Injector {
+        /** Whether a system feature is defined as enabled and available at compile-time. */
+        public boolean isReadOnlySystemEnabledFeature(String featureName, int version) {
+            return Boolean.TRUE.equals(RoSystemFeatures.maybeHasFeature(featureName, version));
+        }
+
+        /** Whether a system feature is defined as disabled and unavailable at compile-time. */
+        public boolean isReadOnlySystemDisabledFeature(String featureName, int version) {
+            return Boolean.FALSE.equals(RoSystemFeatures.maybeHasFeature(featureName, version));
+        }
+
+        /** The full set of system features defined as compile-time enabled and available. */
+        public ArrayMap<String, FeatureInfo> getReadOnlySystemEnabledFeatures() {
+            return RoSystemFeatures.getReadOnlySystemEnabledFeatures();
+        }
+    }
+
+    private final Injector mInjector;
+
     // These are the built-in shared libraries that were read from the
     // system configuration files. Keys are the library names; values are
     // the individual entries that contain information such as filename
@@ -220,7 +245,7 @@
 
     // These are the features this devices supports that were read from the
     // system configuration files.
-    final ArrayMap<String, FeatureInfo> mAvailableFeatures = new ArrayMap<>();
+    final ArrayMap<String, FeatureInfo> mAvailableFeatures;
 
     // These are the features which this device doesn't support; the OEM
     // partition uses these to opt-out of features from the system image.
@@ -602,12 +627,26 @@
     public ArrayMap<String, Integer> getOemDefinedUids() {
         return mOemDefinedUids;
     }
+
     /**
      * Only use for testing. Do NOT use in production code.
      * @param readPermissions false to create an empty SystemConfig; true to read the permissions.
      */
     @VisibleForTesting
     public SystemConfig(boolean readPermissions) {
+        this(readPermissions, new Injector());
+    }
+
+    /**
+     * Only use for testing. Do NOT use in production code.
+     * @param readPermissions false to create an empty SystemConfig; true to read the permissions.
+     * @param injector Additional dependency injection for testing.
+     */
+    @VisibleForTesting
+    public SystemConfig(boolean readPermissions, Injector injector) {
+        mInjector = injector;
+        mAvailableFeatures = mInjector.getReadOnlySystemEnabledFeatures();
+
         if (readPermissions) {
             Slog.w(TAG, "Constructing a test SystemConfig");
             readAllPermissions();
@@ -617,6 +656,9 @@
     }
 
     SystemConfig() {
+        mInjector = new Injector();
+        mAvailableFeatures = mInjector.getReadOnlySystemEnabledFeatures();
+
         TimingsTraceLog log = new TimingsTraceLog(TAG, Trace.TRACE_TAG_SYSTEM_SERVER);
         log.traceBegin("readAllPermissions");
         try {
@@ -1777,6 +1819,10 @@
     }
 
     private void addFeature(String name, int version) {
+        if (mInjector.isReadOnlySystemDisabledFeature(name, version)) {
+            Slog.w(TAG, "Skipping feature addition for compile-time disabled feature: " + name);
+            return;
+        }
         FeatureInfo fi = mAvailableFeatures.get(name);
         if (fi == null) {
             fi = new FeatureInfo();
@@ -1789,6 +1835,10 @@
     }
 
     private void removeFeature(String name) {
+        if (mInjector.isReadOnlySystemEnabledFeature(name, /*version=*/0)) {
+            Slog.w(TAG, "Skipping feature removal for compile-time enabled feature: " + name);
+            return;
+        }
         if (mAvailableFeatures.remove(name) != null) {
             Slog.d(TAG, "Removed unavailable feature " + name);
         }
diff --git a/services/tests/servicestests/src/com/android/server/systemconfig/SystemConfigReadOnlyFeaturesTest.kt b/services/tests/servicestests/src/com/android/server/systemconfig/SystemConfigReadOnlyFeaturesTest.kt
new file mode 100644
index 0000000..22d894a
--- /dev/null
+++ b/services/tests/servicestests/src/com/android/server/systemconfig/SystemConfigReadOnlyFeaturesTest.kt
@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2024 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 com.android.server.systemconfig
+
+import android.content.Context
+import android.content.pm.FeatureInfo
+import android.util.ArrayMap
+import android.util.Xml
+
+import androidx.test.filters.SmallTest
+import androidx.test.platform.app.InstrumentationRegistry
+import com.android.server.SystemConfig
+import com.google.common.truth.Truth.assertThat
+import org.junit.runner.RunWith
+import org.junit.Rule
+
+import org.junit.Test
+import org.junit.rules.TemporaryFolder
+import org.junit.runners.JUnit4
+
+@SmallTest
+@RunWith(JUnit4::class)
+class SystemConfigReadOnlyFeaturesTest {
+
+    companion object {
+        private const val FEATURE_ONE = "feature.test.1"
+        private const val FEATURE_TWO = "feature.test.2"
+        private const val FEATURE_RUNTIME_AVAILABLE_TEMPLATE =
+        """
+            <permissions>
+                <feature name="%s" />
+            </permissions>
+        """
+        private const val FEATURE_RUNTIME_DISABLED_TEMPLATE =
+        """
+            <permissions>
+                <Disabled-feature name="%s" />
+            </permissions>
+        """
+
+        fun featureInfo(featureName: String) = FeatureInfo().apply { name = featureName }
+    }
+
+    private val context: Context = InstrumentationRegistry.getInstrumentation().context
+
+    @get:Rule
+    val tempFolder = TemporaryFolder(context.filesDir)
+
+    private val injector = TestInjector()
+
+    private var uniqueCounter = 0
+
+    @Test
+    fun empty() {
+        assertFeatures().isEmpty()
+    }
+
+    @Test
+    fun readOnlyEnabled() {
+        addReadOnlyEnabledFeature(FEATURE_ONE)
+        addReadOnlyEnabledFeature(FEATURE_TWO)
+
+        assertFeatures().containsAtLeast(FEATURE_ONE, FEATURE_TWO)
+    }
+
+    @Test
+    fun readOnlyAndRuntimeEnabled() {
+        addReadOnlyEnabledFeature(FEATURE_ONE)
+        addRuntimeEnabledFeature(FEATURE_TWO)
+
+        // No issues with matching availability.
+        assertFeatures().containsAtLeast(FEATURE_ONE, FEATURE_TWO)
+    }
+
+    @Test
+    fun readOnlyEnabledRuntimeDisabled() {
+        addReadOnlyEnabledFeature(FEATURE_ONE)
+        addRuntimeDisabledFeature(FEATURE_ONE)
+
+        // Read-only feature availability should take precedence.
+        assertFeatures().contains(FEATURE_ONE)
+    }
+
+    @Test
+    fun readOnlyDisabled() {
+        addReadOnlyDisabledFeature(FEATURE_ONE)
+
+        assertFeatures().doesNotContain(FEATURE_ONE)
+    }
+
+    @Test
+    fun readOnlyAndRuntimeDisabled() {
+        addReadOnlyDisabledFeature(FEATURE_ONE)
+        addRuntimeDisabledFeature(FEATURE_ONE)
+
+        // No issues with matching (un)availability.
+        assertFeatures().doesNotContain(FEATURE_ONE)
+    }
+
+    @Test
+    fun readOnlyDisabledRuntimeEnabled() {
+        addReadOnlyDisabledFeature(FEATURE_ONE)
+        addRuntimeEnabledFeature(FEATURE_ONE)
+        addRuntimeEnabledFeature(FEATURE_TWO)
+
+        // Read-only feature (un)availability should take precedence.
+        assertFeatures().doesNotContain(FEATURE_ONE)
+        assertFeatures().contains(FEATURE_TWO)
+    }
+
+    fun addReadOnlyEnabledFeature(featureName: String) {
+        injector.readOnlyEnabledFeatures[featureName] = featureInfo(featureName)
+    }
+
+    fun addReadOnlyDisabledFeature(featureName: String) {
+        injector.readOnlyDisabledFeatures.add(featureName)
+    }
+
+    fun addRuntimeEnabledFeature(featureName: String) {
+        FEATURE_RUNTIME_AVAILABLE_TEMPLATE.format(featureName).write()
+    }
+
+    fun addRuntimeDisabledFeature(featureName: String) {
+        FEATURE_RUNTIME_DISABLED_TEMPLATE.format(featureName).write()
+    }
+
+    private fun String.write() = tempFolder.root.resolve("${uniqueCounter++}.xml")
+            .writeText(this.trimIndent())
+
+    private fun assertFeatures() = assertThat(availableFeatures().keys)
+
+    private fun availableFeatures() = SystemConfig(false, injector).apply {
+        val parser = Xml.newPullParser()
+        readPermissions(parser, tempFolder.root, /*Grant all permission flags*/ 0.inv())
+    }.let { it.availableFeatures }
+
+    internal class TestInjector() : SystemConfig.Injector() {
+        val readOnlyEnabledFeatures = ArrayMap<String, FeatureInfo>()
+        val readOnlyDisabledFeatures = mutableSetOf<String>()
+
+        override fun isReadOnlySystemEnabledFeature(featureName: String, version: Int): Boolean {
+            return readOnlyEnabledFeatures.containsKey(featureName)
+        }
+
+        override fun isReadOnlySystemDisabledFeature(featureName: String, version: Int): Boolean {
+            return readOnlyDisabledFeatures.contains(featureName)
+        }
+
+        override fun getReadOnlySystemEnabledFeatures(): ArrayMap<String, FeatureInfo> {
+            return readOnlyEnabledFeatures
+        }
+    }
+}
diff --git a/tools/systemfeatures/src/com/android/systemfeatures/SystemFeaturesGenerator.kt b/tools/systemfeatures/src/com/android/systemfeatures/SystemFeaturesGenerator.kt
index cba521e..196b5e7 100644
--- a/tools/systemfeatures/src/com/android/systemfeatures/SystemFeaturesGenerator.kt
+++ b/tools/systemfeatures/src/com/android/systemfeatures/SystemFeaturesGenerator.kt
@@ -22,8 +22,6 @@
 import com.squareup.javapoet.MethodSpec
 import com.squareup.javapoet.ParameterizedTypeName
 import com.squareup.javapoet.TypeSpec
-import java.util.HashMap
-import java.util.Map
 import javax.lang.model.element.Modifier
 
 /*
@@ -52,7 +50,7 @@
  *     public static boolean hasFeatureAutomotive(Context context);
  *     public static boolean hasFeatureLeanback(Context context);
  *     public static Boolean maybeHasFeature(String feature, int version);
- *     public static ArrayMap<String, FeatureInfo> getCompileTimeAvailableFeatures();
+ *     public static ArrayMap<String, FeatureInfo> getReadOnlySystemEnabledFeatures();
  * }
  * </pre>
  */
@@ -63,6 +61,7 @@
     private val PACKAGEMANAGER_CLASS = ClassName.get("android.content.pm", "PackageManager")
     private val CONTEXT_CLASS = ClassName.get("android.content", "Context")
     private val FEATUREINFO_CLASS = ClassName.get("android.content.pm", "FeatureInfo")
+    private val ARRAYMAP_CLASS = ClassName.get("android.util", "ArrayMap")
     private val ASSUME_TRUE_CLASS =
         ClassName.get("com.android.aconfig.annotations", "AssumeTrueForR8")
     private val ASSUME_FALSE_CLASS =
@@ -291,19 +290,19 @@
         features: Collection<FeatureInfo>,
     ) {
         val methodBuilder =
-                MethodSpec.methodBuilder("getCompileTimeAvailableFeatures")
+                MethodSpec.methodBuilder("getReadOnlySystemEnabledFeatures")
                 .addModifiers(Modifier.PUBLIC, Modifier.STATIC)
                 .addAnnotation(ClassName.get("android.annotation", "NonNull"))
                 .addJavadoc("Gets features marked as available at compile-time, keyed by name." +
                         "\n\n@hide")
                 .returns(ParameterizedTypeName.get(
-                        ClassName.get(Map::class.java),
+                        ARRAYMAP_CLASS,
                         ClassName.get(String::class.java),
                         FEATUREINFO_CLASS))
 
         val availableFeatures = features.filter { it.readonly && it.version != null }
-        methodBuilder.addStatement("Map<String, FeatureInfo> features = new \$T<>(\$L)",
-                HashMap::class.java, availableFeatures.size)
+        methodBuilder.addStatement("\$T<String, FeatureInfo> features = new \$T<>(\$L)",
+                ARRAYMAP_CLASS, ARRAYMAP_CLASS, availableFeatures.size)
         if (!availableFeatures.isEmpty()) {
             methodBuilder.addStatement("FeatureInfo fi = new FeatureInfo()")
         }
diff --git a/tools/systemfeatures/tests/golden/RoFeatures.java.gen b/tools/systemfeatures/tests/golden/RoFeatures.java.gen
index edbfc42..ee97b26 100644
--- a/tools/systemfeatures/tests/golden/RoFeatures.java.gen
+++ b/tools/systemfeatures/tests/golden/RoFeatures.java.gen
@@ -13,10 +13,9 @@
 import android.content.Context;
 import android.content.pm.FeatureInfo;
 import android.content.pm.PackageManager;
+import android.util.ArrayMap;
 import com.android.aconfig.annotations.AssumeFalseForR8;
 import com.android.aconfig.annotations.AssumeTrueForR8;
-import java.util.HashMap;
-import java.util.Map;
 
 /**
  * @hide
@@ -94,8 +93,8 @@
      * @hide
      */
     @NonNull
-    public static Map<String, FeatureInfo> getCompileTimeAvailableFeatures() {
-        Map<String, FeatureInfo> features = new HashMap<>(2);
+    public static ArrayMap<String, FeatureInfo> getReadOnlySystemEnabledFeatures() {
+        ArrayMap<String, FeatureInfo> features = new ArrayMap<>(2);
         FeatureInfo fi = new FeatureInfo();
         fi.name = PackageManager.FEATURE_WATCH;
         fi.version = 1;
diff --git a/tools/systemfeatures/tests/golden/RoNoFeatures.java.gen b/tools/systemfeatures/tests/golden/RoNoFeatures.java.gen
index bf7a006..40c7db7 100644
--- a/tools/systemfeatures/tests/golden/RoNoFeatures.java.gen
+++ b/tools/systemfeatures/tests/golden/RoNoFeatures.java.gen
@@ -9,8 +9,7 @@
 import android.content.Context;
 import android.content.pm.FeatureInfo;
 import android.content.pm.PackageManager;
-import java.util.HashMap;
-import java.util.Map;
+import android.util.ArrayMap;
 
 /**
  * @hide
@@ -43,8 +42,8 @@
      * @hide
      */
     @NonNull
-    public static Map<String, FeatureInfo> getCompileTimeAvailableFeatures() {
-        Map<String, FeatureInfo> features = new HashMap<>(0);
+    public static ArrayMap<String, FeatureInfo> getReadOnlySystemEnabledFeatures() {
+        ArrayMap<String, FeatureInfo> features = new ArrayMap<>(0);
         return features;
     }
 }
diff --git a/tools/systemfeatures/tests/golden/RwFeatures.java.gen b/tools/systemfeatures/tests/golden/RwFeatures.java.gen
index b20b228..7bf8961 100644
--- a/tools/systemfeatures/tests/golden/RwFeatures.java.gen
+++ b/tools/systemfeatures/tests/golden/RwFeatures.java.gen
@@ -12,8 +12,7 @@
 import android.content.Context;
 import android.content.pm.FeatureInfo;
 import android.content.pm.PackageManager;
-import java.util.HashMap;
-import java.util.Map;
+import android.util.ArrayMap;
 
 /**
  * @hide
@@ -73,8 +72,8 @@
      * @hide
      */
     @NonNull
-    public static Map<String, FeatureInfo> getCompileTimeAvailableFeatures() {
-        Map<String, FeatureInfo> features = new HashMap<>(0);
+    public static ArrayMap<String, FeatureInfo> getReadOnlySystemEnabledFeatures() {
+        ArrayMap<String, FeatureInfo> features = new ArrayMap<>(0);
         return features;
     }
 }
diff --git a/tools/systemfeatures/tests/golden/RwNoFeatures.java.gen b/tools/systemfeatures/tests/golden/RwNoFeatures.java.gen
index d91f5b6..eb7ec63 100644
--- a/tools/systemfeatures/tests/golden/RwNoFeatures.java.gen
+++ b/tools/systemfeatures/tests/golden/RwNoFeatures.java.gen
@@ -7,8 +7,7 @@
 import android.annotation.Nullable;
 import android.content.Context;
 import android.content.pm.FeatureInfo;
-import java.util.HashMap;
-import java.util.Map;
+import android.util.ArrayMap;
 
 /**
  * @hide
@@ -32,8 +31,8 @@
      * @hide
      */
     @NonNull
-    public static Map<String, FeatureInfo> getCompileTimeAvailableFeatures() {
-        Map<String, FeatureInfo> features = new HashMap<>(0);
+    public static ArrayMap<String, FeatureInfo> getReadOnlySystemEnabledFeatures() {
+        ArrayMap<String, FeatureInfo> features = new ArrayMap<>(0);
         return features;
     }
 }
diff --git a/tools/systemfeatures/tests/src/ArrayMap.java b/tools/systemfeatures/tests/src/ArrayMap.java
new file mode 100644
index 0000000..a5ed9b0
--- /dev/null
+++ b/tools/systemfeatures/tests/src/ArrayMap.java
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2024 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 android.util;
+
+import java.util.HashMap;
+
+/** Stub for testing. */
+public final class ArrayMap<K, V> extends HashMap<K, V> {
+    public ArrayMap(int capacity) {
+        super(capacity);
+    }
+}
diff --git a/tools/systemfeatures/tests/src/SystemFeaturesGeneratorTest.java b/tools/systemfeatures/tests/src/SystemFeaturesGeneratorTest.java
index 39f8fc4..ed3f5c9 100644
--- a/tools/systemfeatures/tests/src/SystemFeaturesGeneratorTest.java
+++ b/tools/systemfeatures/tests/src/SystemFeaturesGeneratorTest.java
@@ -60,7 +60,7 @@
         assertThat(RwNoFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, 0)).isNull();
         assertThat(RwNoFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, 0)).isNull();
         assertThat(RwNoFeatures.maybeHasFeature("com.arbitrary.feature", 0)).isNull();
-        assertThat(RwNoFeatures.getCompileTimeAvailableFeatures()).isEmpty();
+        assertThat(RwNoFeatures.getReadOnlySystemEnabledFeatures()).isEmpty();
     }
 
     @Test
@@ -72,7 +72,7 @@
         assertThat(RoNoFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, 0)).isNull();
         assertThat(RoNoFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, 0)).isNull();
         assertThat(RoNoFeatures.maybeHasFeature("com.arbitrary.feature", 0)).isNull();
-        assertThat(RoNoFeatures.getCompileTimeAvailableFeatures()).isEmpty();
+        assertThat(RoNoFeatures.getReadOnlySystemEnabledFeatures()).isEmpty();
 
         // Also ensure we fall back to the PackageManager for feature APIs without an accompanying
         // versioned feature definition.
@@ -106,7 +106,7 @@
         assertThat(RwFeatures.maybeHasFeature(PackageManager.FEATURE_VULKAN, 0)).isNull();
         assertThat(RwFeatures.maybeHasFeature(PackageManager.FEATURE_AUTO, 0)).isNull();
         assertThat(RwFeatures.maybeHasFeature("com.arbitrary.feature", 0)).isNull();
-        assertThat(RwFeatures.getCompileTimeAvailableFeatures()).isEmpty();
+        assertThat(RwFeatures.getReadOnlySystemEnabledFeatures()).isEmpty();
     }
 
     @Test
@@ -163,7 +163,7 @@
         assertThat(RoFeatures.maybeHasFeature("com.arbitrary.feature", 100)).isNull();
         assertThat(RoFeatures.maybeHasFeature("", 0)).isNull();
 
-        Map<String, FeatureInfo> compiledFeatures = RoFeatures.getCompileTimeAvailableFeatures();
+        Map<String, FeatureInfo> compiledFeatures = RoFeatures.getReadOnlySystemEnabledFeatures();
         assertThat(compiledFeatures.keySet())
                 .containsExactly(PackageManager.FEATURE_WATCH, PackageManager.FEATURE_WIFI);
         assertThat(compiledFeatures.get(PackageManager.FEATURE_WATCH).version).isEqualTo(1);