diff --git a/AndroidProjectTooling.sh b/AndroidProjectTooling.sh
index 0d2afaa..5dd17b2 100755
--- a/AndroidProjectTooling.sh
+++ b/AndroidProjectTooling.sh
@@ -36,6 +36,7 @@ ANDROID_NDK_DIR="$SDK_DIR/ndk/27.2.12479018"
 ANDROID_CMAKE_DIR="$SDK_DIR/cmake/3.22.1"
 ANDROID_TOOLBIN="$ANDROID_NDK_DIR/toolchains/llvm/prebuilt/linux-x86_64/bin"
 STATE_TTL_SECONDS=86400
+HIDE_EMULATOR_WINDOW="false"
 
 log() {
   printf '\n[%s] %s\n' "tooling" "$1"
@@ -642,11 +643,16 @@ start_emulator_if_needed() {
   fi
 
   local emulator_log="$PROJECT_DIR/build/reports/android-emulator.log"
+  local emulator_window_args=()
+  if [ "$HIDE_EMULATOR_WINDOW" = "true" ]; then
+    emulator_window_args=(-no-window)
+  fi
+
   mkdir -p "$(dirname "$emulator_log")"
   log "Starting Android emulator: $ANDROID_TEST_AVD_NAME"
   "$SDK_DIR/emulator/emulator" \
     -avd "$ANDROID_TEST_AVD_NAME" \
-    -no-window \
+    "${emulator_window_args[@]}" \
     -no-audio \
     -no-boot-anim \
     -gpu swiftshader_indirect \
@@ -788,31 +794,54 @@ maybe_run_operation() {
 
 print_usage() {
   cat <<EOF_USAGE
-Usage: bash ./AndroidProjectTooling.sh [--build | --build-release-aab | --test | --clean-test | --test-emulator | --compile-git]
+Usage: bash ./AndroidProjectTooling.sh [--build | --build-release-aab | --test | --clean-test | --test-emulator [--hide-emulator-window] | --compile-git]
 
   --build      Set up the environment and build the debug APK
   --build-release-aab  Set up the environment and build a release Android App Bundle (AAB)
   --test       Set up the environment, compile host Git, and run the debug JVM unit tests with it
   --clean-test Set up the environment, clean Gradle outputs, and run the debug JVM unit tests
-  --test-emulator  Set up an Android emulator and run debug instrumentation tests on it
+  --test-emulator  Set up a visible Android emulator and run debug instrumentation tests on it
+  --hide-emulator-window  Run --test-emulator with the emulator window hidden
   --compile-git  Compile Git for the development host and all Android target ABIs
 EOF_USAGE
 }
 
 validate_args() {
-  case "${1:-}" in
+  local mode="${1:-}"
+  shift || true
+
+  case "$mode" in
     ""|--build|--build-release-aab|--test|--clean-test|--test-emulator|--compile-git)
       ;;
     *)
-      echo "Unknown argument: $1" >&2
+      echo "Unknown argument: $mode" >&2
       print_usage >&2
       exit 1
       ;;
   esac
+
+  while [ "$#" -gt 0 ]; do
+    case "$1" in
+      --hide-emulator-window)
+        if [ "$mode" != "--test-emulator" ]; then
+          echo "--hide-emulator-window can only be used with --test-emulator" >&2
+          print_usage >&2
+          exit 1
+        fi
+        HIDE_EMULATOR_WINDOW="true"
+        ;;
+      *)
+        echo "Unknown argument: $1" >&2
+        print_usage >&2
+        exit 1
+        ;;
+    esac
+    shift
+  done
 }
 
 main() {
-  validate_args "${1:-}"
+  validate_args "$@"
 
   require_tool curl
   require_tool unzip
diff --git a/README.md b/README.md
index bba7db7..c0d3dd8 100644
--- a/README.md
+++ b/README.md
@@ -48,7 +48,8 @@ Available commands:
 | `bash ./AndroidProjectTooling.sh` | Provision or refresh the local Android/JDK toolchain only. | Toolchain under `./jdk` and `./android-sdk` |
 | `bash ./AndroidProjectTooling.sh --test` | Compile host Git, set `GITHUG_TEST_GIT_BINARY`, and run JVM unit tests. | Test reports under `app/build/reports/` |
 | `bash ./AndroidProjectTooling.sh --clean-test` | Compile host Git, clean Gradle outputs, set `GITHUG_TEST_GIT_BINARY`, and run JVM unit tests. | Fresh test reports under `app/build/reports/` |
-| `bash ./AndroidProjectTooling.sh --test-emulator` | Install emulator packages if needed, create/start the project test AVD, compile Android Git, and run debug instrumentation tests. | Instrumentation reports under `app/build/reports/androidTests/` |
+| `bash ./AndroidProjectTooling.sh --test-emulator` | Install emulator packages if needed, create/start the visible project test AVD, compile Android Git, and run debug instrumentation tests. | Instrumentation reports under `app/build/reports/androidTests/` |
+| `bash ./AndroidProjectTooling.sh --test-emulator --hide-emulator-window` | Run the same emulator instrumentation tests without showing the emulator window. | Instrumentation reports under `app/build/reports/androidTests/` |
 | `bash ./AndroidProjectTooling.sh --build` | Build the debug APK. | `app/build/outputs/apk/debug/githug-android-debug-v<versionCode>.apk` |
 | `bash ./AndroidProjectTooling.sh --build-release-aab` | Build the release Android App Bundle. | `app/build/outputs/bundle/release/githug-android-release-v<versionCode>.aab` |
 | `bash ./AndroidProjectTooling.sh --compile-git` | Compile Git for the development host and all Android target ABIs. | Host and Android `libgit.so` binaries |
@@ -65,6 +66,21 @@ To run instrumentation tests on an Android emulator:
 bash ./AndroidProjectTooling.sh --test-emulator
 ```
 
+The emulator window is shown by default so UI instrumentation can be followed visually. Add `--hide-emulator-window` for headless runs:
+
+```bash
+bash ./AndroidProjectTooling.sh --test-emulator --hide-emulator-window
+```
+
+Test outputs and logs are written under project-local build directories:
+
+- JVM test HTML report: `app/build/reports/tests/testDebugUnitTest/index.html`
+- JVM test XML results: `app/build/test-results/testDebugUnitTest/`
+- Emulator instrumentation HTML report: `app/build/reports/androidTests/connected/debug/index.html`
+- Emulator instrumentation XML/results: `app/build/outputs/androidTest-results/connected/debug/`
+- Per-test emulator logcat files: `app/build/outputs/androidTest-results/connected/debug/<device-name>/logcat-*.txt`
+- Emulator startup log: `build/reports/android-emulator.log`
+
 To build installable/debuggable artifacts:
 
 ```bash
@@ -114,7 +130,7 @@ Options:
 | --- | --- | --- |
 | `bash ./AndroidProjectTooling.sh --test` | Ensure the host Git binary is current, then run tests with it. | `build/host-git/libgit.so` and test reports |
 | `bash ./AndroidProjectTooling.sh --clean-test` | Ensure the host Git binary is current, clean Gradle outputs, then run tests with it. | `build/host-git/libgit.so` and fresh test reports |
-| `bash ./AndroidProjectTooling.sh --test-emulator` | Ensure Android ABI Git binaries are current, then run instrumentation tests on the project AVD. | Android `libgit.so` binaries and instrumentation reports |
+| `bash ./AndroidProjectTooling.sh --test-emulator` | Ensure Android ABI Git binaries are current, then run instrumentation tests on the visible project AVD. | Android `libgit.so` binaries and instrumentation reports |
 | `bash ./AndroidProjectTooling.sh --compile-git` | Ensure host Git and Android ABI Git binaries are current. | Host and Android outputs |
 
 Android ABI outputs are generated files and are ignored by git:
diff --git a/app/build.gradle.kts b/app/build.gradle.kts
index 13ed571..af39d0c 100644
--- a/app/build.gradle.kts
+++ b/app/build.gradle.kts
@@ -20,8 +20,8 @@ android {
         applicationId = "solutions.tretter.githugandroid"
         minSdk = 26
         targetSdk = 35
-        versionCode = 173
-        versionName = "0.1.172"
+        versionCode = 174
+        versionName = "0.1.173"
 
         testInstrumentationRunner = "androidx.test.runner.AndroidJUnitRunner"
         vectorDrawables.useSupportLibrary = true
@@ -116,8 +116,10 @@ dependencies {
     implementation("com.google.android.material:material:1.12.0")
 
     testImplementation("junit:junit:4.13.2")
+    androidTestImplementation("androidx.test:core:1.6.1")
     androidTestImplementation("androidx.test:runner:1.6.1")
     androidTestImplementation("androidx.test.ext:junit:1.2.1")
+    androidTestImplementation("androidx.compose.ui:ui-test-junit4")
 
     debugImplementation("androidx.compose.ui:ui-tooling")
     debugImplementation("androidx.compose.ui:ui-test-manifest")
diff --git a/app/src/androidTest/java/solutions/tretter/githugandroid/GitRepositoryRuntimeInstrumentedTest.kt b/app/src/androidTest/java/solutions/tretter/githugandroid/GitRepositoryRuntimeInstrumentedTest.kt
index 794a4be..4eabcce 100644
--- a/app/src/androidTest/java/solutions/tretter/githugandroid/GitRepositoryRuntimeInstrumentedTest.kt
+++ b/app/src/androidTest/java/solutions/tretter/githugandroid/GitRepositoryRuntimeInstrumentedTest.kt
@@ -1,13 +1,27 @@
 package solutions.tretter.githugandroid
 
+import androidx.compose.ui.test.assertIsDisplayed
+import androidx.compose.ui.test.hasText
+import androidx.compose.ui.test.junit4.createEmptyComposeRule
+import androidx.compose.ui.test.onNodeWithTag
+import androidx.compose.ui.test.performClick
+import androidx.compose.ui.test.performImeAction
+import androidx.compose.ui.test.performTextClearance
+import androidx.compose.ui.test.performTextInput
+import androidx.test.core.app.ActivityScenario
 import androidx.test.ext.junit.runners.AndroidJUnit4
 import androidx.test.platform.app.InstrumentationRegistry
+import java.io.File
 import org.junit.Assert.assertTrue
+import org.junit.Rule
 import org.junit.Test
 import org.junit.runner.RunWith
 
 @RunWith(AndroidJUnit4::class)
 class GitRepositoryRuntimeInstrumentedTest {
+    @get:Rule
+    val composeRule = createEmptyComposeRule()
+
     @Test
     fun nativeGitRuntimeCompletesInitLevelOnDevice() {
         val context = InstrumentationRegistry.getInstrumentation().targetContext
@@ -24,19 +38,50 @@ class GitRepositoryRuntimeInstrumentedTest {
     }
 
     @Test
-    fun nativeGitRuntimeCompletesConfigLevelOnDevice() {
+    fun allLevelsCompleteThroughAppTerminalUi() {
+        launchFreshApp().use {
+            allGithugLevels().forEachIndexed { index, level ->
+                waitForExercise(level)
+                level.testCases.first().commands.forEach(::submitTerminalCommand)
+                waitForLevelCompletion(nextLevel = allGithugLevels().getOrNull(index + 1))
+            }
+        }
+    }
+
+    private fun launchFreshApp(): ActivityScenario<MainActivity> {
         val context = InstrumentationRegistry.getInstrumentation().targetContext
-        val runtime = GitRepositoryRuntime(context)
-        val level = configLevel()
+        File(context.applicationInfo.dataDir, "files").deleteRecursively()
+        File(context.applicationInfo.dataDir, "cache").deleteRecursively()
+        val scenario = ActivityScenario.launch(MainActivity::class.java)
+        waitForExercise(initLevel())
+        return scenario
+    }
 
-        assertTrue(runtime.unavailableMessage(), runtime.isNativeGitAvailable())
+    private fun waitForExercise(level: Level) {
+        composeRule.waitUntil(timeoutMillis = 30_000) {
+            composeRule.onAllNodes(hasText(level.title, substring = true)).fetchSemanticsNodes().isNotEmpty()
+        }
+        composeRule.onNodeWithTag("exercise-title-${level.id}").assertIsDisplayed()
+    }
 
-        val repo = runtime.prepareLevel(level)
-        val (namedRepo, _) = runtime.execute(level, repo, "git config user.name GitHug")
-        val (configuredRepo, _) = runtime.execute(level, namedRepo, "git config user.email githug@example.com")
+    private fun waitForLevelCompletion(nextLevel: Level?) {
+        if (nextLevel == null) {
+            composeRule.waitUntil(timeoutMillis = 30_000) {
+                composeRule.onAllNodes(hasText("All Githug levels completed", substring = true)).fetchSemanticsNodes().isNotEmpty()
+            }
+            return
+        }
+        composeRule.waitUntil(timeoutMillis = 30_000) {
+            composeRule.onAllNodes(hasText(nextLevel.title, substring = true)).fetchSemanticsNodes().isNotEmpty()
+        }
+        composeRule.onNodeWithTag("exercise-title-${nextLevel.id}").assertIsDisplayed()
+    }
 
-        assertTrue(configuredRepo.config["user.name"].orEmpty().isNotBlank())
-        assertTrue(configuredRepo.config["user.email"].orEmpty().isNotBlank())
-        assertTrue(level.validator(configuredRepo, "git config user.email githug@example.com"))
+    private fun submitTerminalCommand(command: String) {
+        val input = composeRule.onNodeWithTag("terminal-command-input")
+        input.performClick()
+        input.performTextClearance()
+        input.performTextInput(command)
+        input.performImeAction()
     }
 }
diff --git a/app/src/main/cpp/githug_runtime.c b/app/src/main/cpp/githug_runtime.c
index 919f448..6149ec9 100644
--- a/app/src/main/cpp/githug_runtime.c
+++ b/app/src/main/cpp/githug_runtime.c
@@ -21,11 +21,6 @@ struct output_buffer {
     size_t capacity;
 };
 
-struct reader_state {
-    int fd;
-    struct output_buffer output;
-};
-
 static pthread_mutex_t git_mutex = PTHREAD_MUTEX_INITIALIZER;
 static void *git_handle = NULL;
 static git_main_fn git_main = NULL;
@@ -54,23 +49,28 @@ static int append_output(struct output_buffer *buffer, const char *data, size_t
     return 0;
 }
 
-static void *read_output(void *arg) {
-    struct reader_state *state = (struct reader_state *)arg;
+static int drain_available_output(int fd, struct output_buffer *output, int *saw_eof) {
     char chunk[4096];
     for (;;) {
-        ssize_t count = read(state->fd, chunk, sizeof(chunk));
+        ssize_t count = read(fd, chunk, sizeof(chunk));
         if (count > 0) {
-            if (append_output(&state->output, chunk, (size_t)count) != 0) {
-                break;
+            if (append_output(output, chunk, (size_t)count) != 0) {
+                return -1;
             }
-        } else if (count == 0) {
-            break;
-        } else if (errno != EINTR) {
-            break;
+            continue;
         }
+        if (count == 0) {
+            *saw_eof = 1;
+            return 0;
+        }
+        if (errno == EINTR) {
+            continue;
+        }
+        if (errno == EAGAIN || errno == EWOULDBLOCK) {
+            return 0;
+        }
+        return -1;
     }
-    close(state->fd);
-    return NULL;
 }
 
 static jobjectArray make_result(JNIEnv *env, int exit_code, const char *output) {
@@ -267,12 +267,36 @@ Java_solutions_tretter_githugandroid_NativeGitBridge_runGitMainNative(
     }
 
     close(pipe_fds[1]);
-    struct reader_state reader = { .fd = pipe_fds[0], .output = {0} };
-    read_output(&reader);
+    struct output_buffer output = {0};
+    int flags = fcntl(pipe_fds[0], F_GETFL, 0);
+    if (flags >= 0) {
+        fcntl(pipe_fds[0], F_SETFL, flags | O_NONBLOCK);
+    }
 
     int child_status = 0;
-    while (waitpid(child, &child_status, 0) < 0 && errno == EINTR) {
+    int child_done = 0;
+    int saw_eof = 0;
+    while (!child_done || !saw_eof) {
+        if (drain_available_output(pipe_fds[0], &output, &saw_eof) != 0) {
+            break;
+        }
+        if (!child_done) {
+            pid_t wait_result = waitpid(child, &child_status, WNOHANG);
+            if (wait_result == child) {
+                child_done = 1;
+            } else if (wait_result < 0 && errno != EINTR) {
+                child_done = 1;
+            }
+        }
+        if (child_done) {
+            if (!saw_eof) {
+                drain_available_output(pipe_fds[0], &output, &saw_eof);
+            }
+            break;
+        }
+        usleep(10000);
     }
+    close(pipe_fds[0]);
     pthread_mutex_unlock(&git_mutex);
 
     int exit_code = -1;
@@ -282,9 +306,9 @@ Java_solutions_tretter_githugandroid_NativeGitBridge_runGitMainNative(
         exit_code = 128 + WTERMSIG(child_status);
     }
 
-    jobjectArray result = make_result(env, exit_code, reader.output.data);
+    jobjectArray result = make_result(env, exit_code, output.data);
 
-    free(reader.output.data);
+    free(output.data);
     free_string_array(argv, argc);
     free_string_array(env_entries, envc);
     (*env)->ReleaseStringUTFChars(env, library_path, library_path_chars);
diff --git a/app/src/main/java/solutions/tretter/githugandroid/Exercise.kt b/app/src/main/java/solutions/tretter/githugandroid/Exercise.kt
index 054c39d..68f3059 100644
--- a/app/src/main/java/solutions/tretter/githugandroid/Exercise.kt
+++ b/app/src/main/java/solutions/tretter/githugandroid/Exercise.kt
@@ -25,6 +25,7 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.Path
 import androidx.compose.ui.layout.boundsInRoot
 import androidx.compose.ui.layout.onGloballyPositioned
+import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
@@ -51,7 +52,12 @@ fun ExercisePane(
         }
         SelectionContainer {
             Column(verticalArrangement = Arrangement.spacedBy(12.dp)) {
-                Text(level.title, style = MaterialTheme.typography.titleLarge, color = TextPrimary)
+                Text(
+                    text = level.title,
+                    modifier = Modifier.testTag("exercise-title-${level.id}"),
+                    style = MaterialTheme.typography.titleLarge,
+                    color = TextPrimary,
+                )
                 Text(level.description, color = TextSecondary)
             }
         }
diff --git a/app/src/main/java/solutions/tretter/githugandroid/Levels.kt b/app/src/main/java/solutions/tretter/githugandroid/Levels.kt
index 5ede601..fbb9745 100644
--- a/app/src/main/java/solutions/tretter/githugandroid/Levels.kt
+++ b/app/src/main/java/solutions/tretter/githugandroid/Levels.kt
@@ -11,6 +11,7 @@ import androidx.compose.material3.Text
 import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.unit.dp
 
 @Composable
@@ -33,7 +34,9 @@ fun LevelsPane(
             ) {
                 TextButton(
                     onClick = { onSelect(index) },
-                    modifier = Modifier.fillMaxWidth(),
+                    modifier = Modifier
+                        .fillMaxWidth()
+                        .testTag("level-${level.id}"),
                     colors = ButtonDefaults.textButtonColors(
                         contentColor = if (index == currentLevelIndex) Accent else TextSecondary,
                     ),
@@ -49,4 +52,4 @@ fun LevelsPane(
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/app/src/main/java/solutions/tretter/githugandroid/Terminal.kt b/app/src/main/java/solutions/tretter/githugandroid/Terminal.kt
index b440c4d..213bfbf 100644
--- a/app/src/main/java/solutions/tretter/githugandroid/Terminal.kt
+++ b/app/src/main/java/solutions/tretter/githugandroid/Terminal.kt
@@ -45,6 +45,7 @@ import androidx.compose.ui.input.key.key
 import androidx.compose.ui.input.key.onPreviewKeyEvent
 import androidx.compose.ui.input.key.type
 import androidx.compose.ui.platform.LocalConfiguration
+import androidx.compose.ui.platform.testTag
 import androidx.compose.ui.text.SpanStyle
 import androidx.compose.ui.text.TextRange
 import androidx.compose.ui.text.TextStyle
@@ -232,6 +233,7 @@ private fun RowScope.TerminalInputField(
             onValueChange = onValueChange,
             modifier = Modifier
                 .weight(1f)
+                .testTag("terminal-command-input")
                 .focusRequester(focusRequester)
                 .onFocusChanged { state ->
                     if (state.isFocused) {