Package the desktop app as the web build, and delete the Linux embedder

Completes the move off Flutter's Linux embedder, which manages ~20fps at 4K
against ~144fps for the same Dart code in Chrome (measured end-to-end: the real
app, fullscreen at 4K, sustains 144fps scrolling a 300-note list).

`linux/` is gone. Its icons and .desktop installer move to `desktop/`, since
those are still needed and are not Flutter platform scaffolding. install_arch.sh
now builds the web bundle plus an AOT wrapper; run.sh does the same for
development.

Four things this took to get right, each found by actually installing and
launching the package rather than assuming:

- `dart compile exe` refuses to build the package: transitive dependencies
  (sqlite3, objective_c) have native build hooks. `dart build cli` handles them,
  and emits bin/ + lib/, so the wrapper resolves its assets at ../web.
- `options=('!strip')` is load-bearing. makepkg stripped the AOT executable
  (7.0M -> 5.7M), discarding the embedded snapshot; the result still ran but was
  the bare Dart VM printing a usage message instead of the app.
- No hard browser dependency. Declaring `depends=('chromium')` made makepkg
  install it, and this machine has a policy that uninstalls chromium three
  seconds later, which then failed dependency resolution. The wrapper discovers
  whatever browser exists (Thorium included) and TODO_BROWSER overrides.
- The server no longer dies with the browser process. Chrome exits immediately
  when handing off to an instance that owns the profile -- or when a stale
  SingletonLock is left behind -- which killed the server out from under a live
  window.

Chrome gets --class=todo so WM_CLASS matches the .desktop StartupWMClass and
the taskbar shows the app icon rather than a browser icon.

Verified: `todo` launches, serves, opens a window titled todo, and recovers the
backlog through the wrapper.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -1,6 +1,13 @@
 # CLAUDE.md — todo
 
-Offline-first, CRDT-synced notes app. Flutter, targets **Android + Linux**.
+Offline-first, CRDT-synced notes app. Flutter, targets **Android + web**.
+
+The **desktop app is the web build**, served by a small local wrapper
+(`bin/todo_desktop.dart`) and shown in a Chrome `--app` window. Flutter's Linux
+embedder was removed: it manages only ~20fps at 4K while the same Dart code in
+Chrome sustains ~144fps. See `docs/desktop-performance-findings.md` for the
+measurements. Do not re-add `linux/` — `flutter create --platforms linux` would
+silently bring the slow path back.
 Capture an idea instantly (persisted on every keystroke), browse/filter notes,
 and sync peer-to-peer through a GitHub repo used as dumb storage.
 
@@ -24,7 +31,12 @@ and sync peer-to-peer through a GitHub repo used as dumb storage.
 - Coverage summary: `lcov --list coverage/lcov.info`.
 - Static analysis: `flutter analyze` (must be clean before committing).
 - Format: `dart format lib/ test/`.
-- Run the app: `flutter run` (Linux desktop or a connected Android device).
+- Run the desktop app: `./run.sh` (builds the web bundle, starts the wrapper,
+  opens Chrome). Mobile: `flutter run` with a connected Android device.
+- The wrapper serves on a **fixed** port 8730 with a **fixed** Chrome profile
+  dir. Both must stay fixed: the GitHub token (`localStorage`) and the notes
+  (IndexedDB) are keyed by origin and live in that profile, so changing either
+  silently logs you out and hides your notes.
 - Release APK: `flutter build apk --release` (signs with the debug key; debug
   builds are janky — always measure smoothness on a release build).
 - Sync smoke test (hits real GitHub, needs a token): `dart run tool/sync_smoke.dart`.

bin/todo_desktop.dart

@@ -19,10 +19,12 @@ Future<void> main(List<String> args) async {
     exit(1);
   }
 
-  // Assets sit next to this executable when installed; --web-root overrides for
-  // development runs straight out of the repo.
+  // `dart build cli` emits bundle/bin/<exe> alongside bundle/lib/, so the
+  // installed layout is /opt/todo/bin/todo-desktop with the web assets one
+  // level up at /opt/todo/web. --web-root overrides for development runs
+  // straight out of the repo.
   final webRoot = _argValue(args, '--web-root') ??
-      p.join(p.dirname(Platform.resolvedExecutable), 'web');
+      p.normalize(p.join(p.dirname(Platform.resolvedExecutable), '..', 'web'));
   if (!Directory(webRoot).existsSync()) {
     stderr.writeln('web assets not found at $webRoot');
     exit(1);
@@ -40,37 +42,67 @@ Future<void> main(List<String> args) async {
   await server.start(_port);
   stdout.writeln('todo desktop serving on http://localhost:$_port');
 
-  if (_argValue(args, '--no-browser') == null) {
-    await _launchBrowser(home);
-    // The browser owns the session: when its window closes, so does the app.
+  // A bare flag, not a valued option: requiring a dummy value meant passing a
+  // stray positional, which the AOT runtime tries to interpret as a snapshot.
+  if (!args.contains('--no-browser')) {
+    final ranLongEnough = await _launchBrowser(home);
+    if (!ranLongEnough) {
+      // Chrome exits immediately when it hands the URL to an instance that
+      // already owns the profile directory (or when a stale SingletonLock is
+      // left behind). Shutting down here would pull the server out from under
+      // a window that is still open, so keep serving instead.
+      stdout.writeln(
+        'Browser returned immediately (handed off to an existing window). '
+        'Still serving on http://localhost:$_port — Ctrl-C to stop.',
+      );
+      return;
+    }
+    // Otherwise the browser owned the session: its window closed, so we exit.
     await server.stop();
   }
 }
 
 /// Launches the app in a Chrome-family browser with a **stable** profile
 /// directory, since the token and notes live in that profile.
-Future<void> _launchBrowser(String home) async {
-  const candidates = [
+/// Returns true when the browser ran long enough to have owned the session.
+Future<bool> _launchBrowser(String home) async {
+  // Ordered by preference, and deliberately broad: this machine runs Thorium
+  // behind /opt/google/chrome, and has a policy that uninstalls the `chromium`
+  // package, so assuming any single browser is wrong. TODO_BROWSER overrides.
+  final candidates = [
+    Platform.environment['TODO_BROWSER'] ?? '',
     '/opt/google/chrome/chrome',
-    '/usr/bin/chromium',
+    '/opt/thorium-browser/thorium-browser',
     '/usr/bin/google-chrome-stable',
+    '/usr/bin/chromium',
+    '/usr/bin/brave',
   ];
   final browser = candidates.firstWhere(
-    (path) => File(path).existsSync(),
+    (path) => path.isNotEmpty && File(path).existsSync(),
     orElse: () => '',
   );
   if (browser.isEmpty) {
     stderr.writeln('No Chrome-family browser found; open '
         'http://localhost:$_port manually.');
-    return;
+    return false;
   }
+  // The profile directory must stay stable: the GitHub token (localStorage)
+  // and the notes (IndexedDB) live inside it, so a changing path silently
+  // logs the user out and hides their notes.
   final profile = p.join(home, '.local', 'share', 'todo-desktop', 'profile');
   final process = await Process.start(browser, [
     '--app=http://localhost:$_port',
     '--user-data-dir=$profile',
+    // Sets WM_CLASS, which the .desktop entry matches on via StartupWMClass.
+    // Without it the window inherits the browser's class and the taskbar shows
+    // a browser icon instead of todo's.
+    '--class=todo',
     '--no-first-run',
   ]);
+
+  final started = DateTime.now();
   await process.exitCode;
+  return DateTime.now().difference(started) > const Duration(seconds: 5);
 }
 
 String? _argValue(List<String> args, String name) {

desktop/install_desktop_entry.sh

@@ -3,32 +3,38 @@
 # ============================================================================
 # Install the todo launcher icon and .desktop entry for the Linux desktop.
 #
-# Flutter's GTK runner has no icon of its own: my_application.cc calls
-# gtk_window_set_icon_name("todo"), which resolves through the hicolor icon
-# theme. This script is what puts the icon into that theme, plus a .desktop
-# entry so the app appears in application menus.
+# The desktop app is a Flutter *web* build shown in a Chrome app window (the
+# Linux embedder manages only ~20fps at 4K — see
+# docs/desktop-performance-findings.md), so the launcher starts the wrapper,
+# which serves the build and opens the browser.
 #
-# Icon PNGs are pre-rendered and committed under linux/icons/, so this script
+# Icon PNGs are pre-rendered and committed under desktop/icons/, so this script
 # needs no image tooling at run time. Regenerate them with:
 #   PYTHONPATH=~/testsAndMisc python3 -m python_pkg.app_icons \
-#       generate --app todo --linux-out linux/icons
+#       generate --app todo --linux-out desktop/icons
 # ============================================================================
 
 set -euo pipefail
 
 SCRIPT_NAME="$(basename "$0")"
-LINUX_DIR="$(cd "$(dirname "$0")" && pwd)"
-REPO_DIR="$(dirname "$LINUX_DIR")"
-readonly SCRIPT_NAME LINUX_DIR REPO_DIR
+DESKTOP_DIR_SRC="$(cd "$(dirname "$0")" && pwd)"
+REPO_DIR="$(dirname "$DESKTOP_DIR_SRC")"
+readonly SCRIPT_NAME DESKTOP_DIR_SRC REPO_DIR
 readonly ICON_NAME="todo"
-readonly BINARY_NAME="todo"
-# GTK derives WM_CLASS from the GApplication id in linux/CMakeLists.txt,
-# not from the binary name; verified with xprop on the running window.
-readonly WM_CLASS="dev.kuhy.todo"
-readonly ICON_SRC_DIR="$LINUX_DIR/icons"
+# Chrome sets WM_CLASS from --class, which the wrapper passes explicitly.
+# Without it the window would inherit the browser's own class (e.g.
+# "Google-chrome"), and the taskbar would show a browser icon for the app.
+readonly WM_CLASS="todo"
+readonly ICON_SRC_DIR="$DESKTOP_DIR_SRC/icons"
 readonly ICON_THEME_DIR="${XDG_DATA_HOME:-$HOME/.local/share}/icons/hicolor"
 readonly DESKTOP_DIR="${XDG_DATA_HOME:-$HOME/.local/share}/applications"
-readonly BUNDLE_BIN="$REPO_DIR/build/linux/x64/release/bundle/$BINARY_NAME"
+# Prefer the packaged launcher; fall back to running straight from the repo so
+# the entry also works for a development checkout that was never installed.
+LAUNCH_CMD="/usr/bin/todo"
+if [[ ! -x "$LAUNCH_CMD" ]]; then
+    LAUNCH_CMD="$REPO_DIR/run.sh"
+fi
+readonly LAUNCH_CMD
 
 usage() {
     echo "Usage: $SCRIPT_NAME"
@@ -79,7 +85,7 @@ install_desktop_entry() {
 Type=Application
 Name=todo
 Comment=Offline-first, CRDT-synced notes
-Exec=$BUNDLE_BIN
+Exec=$LAUNCH_CMD
 Icon=$ICON_NAME
 Terminal=false
 Categories=Utility;TextEditor;
@@ -97,9 +103,9 @@ main() {
     install_desktop_entry
     echo "Installed $ICON_NAME icon into $ICON_THEME_DIR"
     echo "Installed $DESKTOP_DIR/$ICON_NAME.desktop"
-    if [[ ! -x "$BUNDLE_BIN" ]]; then
-        echo "Note: $BUNDLE_BIN does not exist yet."
-        echo "      Run 'flutter build linux --release' to make the entry launchable."
+    if [[ ! -x "$LAUNCH_CMD" ]]; then
+        echo "Note: $LAUNCH_CMD does not exist yet."
+        echo "      Run ./install_arch.sh to build and install the app."
     fi
 }
 

install_arch.sh

@@ -6,7 +6,12 @@
 set -euo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-BUNDLE_DIR="$SCRIPT_DIR/build/linux/x64/release/bundle"
+# The desktop app is a Flutter *web* build served by a small local wrapper.
+# Flutter's Linux embedder only reaches ~20fps at 4K on this hardware, while
+# the same Dart code in Chrome sustains ~144fps — see
+# docs/desktop-performance-findings.md for the measurements.
+WEB_DIR="$SCRIPT_DIR/build/web"
+WRAPPER_BUNDLE="$SCRIPT_DIR/build/cli/bundle"
 WORK_DIR="$(mktemp -d)"
 
 cleanup() { rm -rf "$WORK_DIR"; }
@@ -15,9 +20,17 @@ trap cleanup EXIT
 # Parse version from pubspec.yaml (strip build number: 1.0.0+1 → 1.0.0)
 PKGVER="$(grep '^version:' "$SCRIPT_DIR/pubspec.yaml" | sed 's/^version:[[:space:]]*//' | sed 's/+.*//')"
 
-echo "==> Building todo $PKGVER (Flutter release)..."
+echo "==> Building todo $PKGVER (Flutter web release)..."
 cd "$SCRIPT_DIR"
-flutter build linux --release
+flutter build web --release
+
+echo "==> Compiling the desktop wrapper..."
+# AOT-compiled so the installed package needs no Dart SDK at run time.
+# `dart build cli`, not `dart compile exe`: the package pulls in dependencies
+# with native build hooks (sqlite3, objective_c), which `dart compile` refuses
+# to handle even though the wrapper itself uses none of them.
+rm -rf "$SCRIPT_DIR/build/cli"
+dart build cli -o "$SCRIPT_DIR/build/cli"
 
 echo "==> Generating PKGBUILD..."
 # pkgname is 'todo-flutter', NOT 'todo': the AUR already ships an unrelated
@@ -33,24 +46,41 @@ pkgdesc='Offline-first notes app'
 arch=('x86_64')
 url='https://github.com/kuhyx/todo-app'
 license=('custom')
-depends=('gtk3')
+# No hard browser dependency. A Chrome-family browser renders the UI, but
+# naming one as a dependency is wrong here: makepkg installs it, and this
+# system has a policy that immediately removes 'chromium' again, which then
+# fails dependency resolution. The wrapper discovers whatever browser is
+# actually present (including Thorium) and reports clearly if none is.
+depends=()
+optdepends=('chromium: renders the app window'
+            'google-chrome: renders the app window')
 conflicts=('todo')
 replaces=('todo')
 # Flutter release binaries are already stripped/AOT-compiled with no
 # extractable DWARF debug info, so a split -debug package is pointless here
 # and gdb-add-index just fails noisily on every binary. Skip it, overriding
 # the system-wide 'debug' OPTIONS setting.
-options=('!debug')
+# !strip is load-bearing: the wrapper is a Dart AOT executable with its snapshot
+# embedded in the ELF, and stripping it discards that snapshot. The stripped
+# binary still runs but is just the bare Dart VM, which prints a usage message
+# instead of starting the app.
+options=('!strip' '!debug')
 
 package() {
+    # Preserve the bundle's bin/ + lib/ layout: the executable loads its
+    # native libraries from ../lib, and resolves the web assets from ../web.
     install -dm755 "\$pkgdir/opt/todo"
-    cp -r "$BUNDLE_DIR/." "\$pkgdir/opt/todo/"
-    chmod 755 "\$pkgdir/opt/todo/todo"
+    cp -r "$WRAPPER_BUNDLE/bin" "\$pkgdir/opt/todo/bin"
+    cp -r "$WRAPPER_BUNDLE/lib" "\$pkgdir/opt/todo/lib"
+    chmod 755 "\$pkgdir/opt/todo/bin/todo_desktop"
+
+    install -dm755 "\$pkgdir/opt/todo/web"
+    cp -r "$WEB_DIR/." "\$pkgdir/opt/todo/web/"
 
     install -dm755 "\$pkgdir/usr/bin"
     cat > "\$pkgdir/usr/bin/todo" <<'WRAPPER'
 #!/bin/bash
-exec /opt/todo/todo "\$@"
+exec /opt/todo/bin/todo_desktop "\$@"
 WRAPPER
     chmod 755 "\$pkgdir/usr/bin/todo"
 }

linux/.gitignore

@@ -1 +0,0 @@
-flutter/ephemeral

linux/CMakeLists.txt

@@ -1,128 +0,0 @@
-# Project-level configuration.
-cmake_minimum_required(VERSION 3.13)
-project(runner LANGUAGES CXX)
-
-# The name of the executable created for the application. Change this to change
-# the on-disk name of your application.
-set(BINARY_NAME "todo")
-# The unique GTK application identifier for this application. See:
-# https://wiki.gnome.org/HowDoI/ChooseApplicationID
-set(APPLICATION_ID "dev.kuhy.todo")
-
-# Explicitly opt in to modern CMake behaviors to avoid warnings with recent
-# versions of CMake.
-cmake_policy(SET CMP0063 NEW)
-
-# Load bundled libraries from the lib/ directory relative to the binary.
-set(CMAKE_INSTALL_RPATH "$ORIGIN/lib")
-
-# Root filesystem for cross-building.
-if(FLUTTER_TARGET_PLATFORM_SYSROOT)
-  set(CMAKE_SYSROOT ${FLUTTER_TARGET_PLATFORM_SYSROOT})
-  set(CMAKE_FIND_ROOT_PATH ${CMAKE_SYSROOT})
-  set(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
-  set(CMAKE_FIND_ROOT_PATH_MODE_PACKAGE ONLY)
-  set(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
-  set(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)
-endif()
-
-# Define build configuration options.
-if(NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
-  set(CMAKE_BUILD_TYPE "Debug" CACHE
-    STRING "Flutter build mode" FORCE)
-  set_property(CACHE CMAKE_BUILD_TYPE PROPERTY STRINGS
-    "Debug" "Profile" "Release")
-endif()
-
-# Compilation settings that should be applied to most targets.
-#
-# Be cautious about adding new options here, as plugins use this function by
-# default. In most cases, you should add new options to specific targets instead
-# of modifying this function.
-function(APPLY_STANDARD_SETTINGS TARGET)
-  target_compile_features(${TARGET} PUBLIC cxx_std_14)
-  target_compile_options(${TARGET} PRIVATE -Wall -Werror)
-  target_compile_options(${TARGET} PRIVATE "$<$<NOT:$<CONFIG:Debug>>:-O3>")
-  target_compile_definitions(${TARGET} PRIVATE "$<$<NOT:$<CONFIG:Debug>>:NDEBUG>")
-endfunction()
-
-# Flutter library and tool build rules.
-set(FLUTTER_MANAGED_DIR "${CMAKE_CURRENT_SOURCE_DIR}/flutter")
-add_subdirectory(${FLUTTER_MANAGED_DIR})
-
-# System-level dependencies.
-find_package(PkgConfig REQUIRED)
-pkg_check_modules(GTK REQUIRED IMPORTED_TARGET gtk+-3.0)
-
-# Application build; see runner/CMakeLists.txt.
-add_subdirectory("runner")
-
-# Run the Flutter tool portions of the build. This must not be removed.
-add_dependencies(${BINARY_NAME} flutter_assemble)
-
-# Only the install-generated bundle's copy of the executable will launch
-# correctly, since the resources must in the right relative locations. To avoid
-# people trying to run the unbundled copy, put it in a subdirectory instead of
-# the default top-level location.
-set_target_properties(${BINARY_NAME}
-  PROPERTIES
-  RUNTIME_OUTPUT_DIRECTORY "${CMAKE_BINARY_DIR}/intermediates_do_not_run"
-)
-
-
-# Generated plugin build rules, which manage building the plugins and adding
-# them to the application.
-include(flutter/generated_plugins.cmake)
-
-
-# === Installation ===
-# By default, "installing" just makes a relocatable bundle in the build
-# directory.
-set(BUILD_BUNDLE_DIR "${PROJECT_BINARY_DIR}/bundle")
-if(CMAKE_INSTALL_PREFIX_INITIALIZED_TO_DEFAULT)
-  set(CMAKE_INSTALL_PREFIX "${BUILD_BUNDLE_DIR}" CACHE PATH "..." FORCE)
-endif()
-
-# Start with a clean build bundle directory every time.
-install(CODE "
-  file(REMOVE_RECURSE \"${BUILD_BUNDLE_DIR}/\")
-  " COMPONENT Runtime)
-
-set(INSTALL_BUNDLE_DATA_DIR "${CMAKE_INSTALL_PREFIX}/data")
-set(INSTALL_BUNDLE_LIB_DIR "${CMAKE_INSTALL_PREFIX}/lib")
-
-install(TARGETS ${BINARY_NAME} RUNTIME DESTINATION "${CMAKE_INSTALL_PREFIX}"
-  COMPONENT Runtime)
-
-install(FILES "${FLUTTER_ICU_DATA_FILE}" DESTINATION "${INSTALL_BUNDLE_DATA_DIR}"
-  COMPONENT Runtime)
-
-install(FILES "${FLUTTER_LIBRARY}" DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
-  COMPONENT Runtime)
-
-foreach(bundled_library ${PLUGIN_BUNDLED_LIBRARIES})
-  install(FILES "${bundled_library}"
-    DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
-    COMPONENT Runtime)
-endforeach(bundled_library)
-
-# Copy the native assets provided by the build.dart from all packages.
-set(NATIVE_ASSETS_DIR "${PROJECT_BUILD_DIR}native_assets/linux/")
-install(DIRECTORY "${NATIVE_ASSETS_DIR}"
-   DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
-   COMPONENT Runtime)
-
-# Fully re-copy the assets directory on each build to avoid having stale files
-# from a previous install.
-set(FLUTTER_ASSET_DIR_NAME "flutter_assets")
-install(CODE "
-  file(REMOVE_RECURSE \"${INSTALL_BUNDLE_DATA_DIR}/${FLUTTER_ASSET_DIR_NAME}\")
-  " COMPONENT Runtime)
-install(DIRECTORY "${PROJECT_BUILD_DIR}/${FLUTTER_ASSET_DIR_NAME}"
-  DESTINATION "${INSTALL_BUNDLE_DATA_DIR}" COMPONENT Runtime)
-
-# Install the AOT library on non-Debug builds only.
-if(NOT CMAKE_BUILD_TYPE MATCHES "Debug")
-  install(FILES "${AOT_LIBRARY}" DESTINATION "${INSTALL_BUNDLE_LIB_DIR}"
-    COMPONENT Runtime)
-endif()

linux/flutter/CMakeLists.txt

@@ -1,88 +0,0 @@
-# This file controls Flutter-level build steps. It should not be edited.
-cmake_minimum_required(VERSION 3.10)
-
-set(EPHEMERAL_DIR "${CMAKE_CURRENT_SOURCE_DIR}/ephemeral")
-
-# Configuration provided via flutter tool.
-include(${EPHEMERAL_DIR}/generated_config.cmake)
-
-# TODO: Move the rest of this into files in ephemeral. See
-# https://github.com/flutter/flutter/issues/57146.
-
-# Serves the same purpose as list(TRANSFORM ... PREPEND ...),
-# which isn't available in 3.10.
-function(list_prepend LIST_NAME PREFIX)
-    set(NEW_LIST "")
-    foreach(element ${${LIST_NAME}})
-        list(APPEND NEW_LIST "${PREFIX}${element}")
-    endforeach(element)
-    set(${LIST_NAME} "${NEW_LIST}" PARENT_SCOPE)
-endfunction()
-
-# === Flutter Library ===
-# System-level dependencies.
-find_package(PkgConfig REQUIRED)
-pkg_check_modules(GTK REQUIRED IMPORTED_TARGET gtk+-3.0)
-pkg_check_modules(GLIB REQUIRED IMPORTED_TARGET glib-2.0)
-pkg_check_modules(GIO REQUIRED IMPORTED_TARGET gio-2.0)
-
-set(FLUTTER_LIBRARY "${EPHEMERAL_DIR}/libflutter_linux_gtk.so")
-
-# Published to parent scope for install step.
-set(FLUTTER_LIBRARY ${FLUTTER_LIBRARY} PARENT_SCOPE)
-set(FLUTTER_ICU_DATA_FILE "${EPHEMERAL_DIR}/icudtl.dat" PARENT_SCOPE)
-set(PROJECT_BUILD_DIR "${PROJECT_DIR}/build/" PARENT_SCOPE)
-set(AOT_LIBRARY "${PROJECT_DIR}/build/lib/libapp.so" PARENT_SCOPE)
-
-list(APPEND FLUTTER_LIBRARY_HEADERS
-  "fl_basic_message_channel.h"
-  "fl_binary_codec.h"
-  "fl_binary_messenger.h"
-  "fl_dart_project.h"
-  "fl_engine.h"
-  "fl_json_message_codec.h"
-  "fl_json_method_codec.h"
-  "fl_message_codec.h"
-  "fl_method_call.h"
-  "fl_method_channel.h"
-  "fl_method_codec.h"
-  "fl_method_response.h"
-  "fl_plugin_registrar.h"
-  "fl_plugin_registry.h"
-  "fl_standard_message_codec.h"
-  "fl_standard_method_codec.h"
-  "fl_string_codec.h"
-  "fl_value.h"
-  "fl_view.h"
-  "flutter_linux.h"
-)
-list_prepend(FLUTTER_LIBRARY_HEADERS "${EPHEMERAL_DIR}/flutter_linux/")
-add_library(flutter INTERFACE)
-target_include_directories(flutter INTERFACE
-  "${EPHEMERAL_DIR}"
-)
-target_link_libraries(flutter INTERFACE "${FLUTTER_LIBRARY}")
-target_link_libraries(flutter INTERFACE
-  PkgConfig::GTK
-  PkgConfig::GLIB
-  PkgConfig::GIO
-)
-add_dependencies(flutter flutter_assemble)
-
-# === Flutter tool backend ===
-# _phony_ is a non-existent file to force this command to run every time,
-# since currently there's no way to get a full input/output list from the
-# flutter tool.
-add_custom_command(
-  OUTPUT ${FLUTTER_LIBRARY} ${FLUTTER_LIBRARY_HEADERS}
-    ${CMAKE_CURRENT_BINARY_DIR}/_phony_
-  COMMAND ${CMAKE_COMMAND} -E env
-    ${FLUTTER_TOOL_ENVIRONMENT}
-    "${FLUTTER_ROOT}/packages/flutter_tools/bin/tool_backend.sh"
-      ${FLUTTER_TARGET_PLATFORM} ${CMAKE_BUILD_TYPE}
-  VERBATIM
-)
-add_custom_target(flutter_assemble DEPENDS
-  "${FLUTTER_LIBRARY}"
-  ${FLUTTER_LIBRARY_HEADERS}
-)

linux/flutter/generated_plugin_registrant.cc

@@ -1,23 +0,0 @@
-//
-//  Generated file. Do not edit.
-//
-
-// clang-format off
-
-#include "generated_plugin_registrant.h"
-
-#include <file_selector_linux/file_selector_plugin.h>
-#include <flutter_secure_storage_linux/flutter_secure_storage_linux_plugin.h>
-#include <url_launcher_linux/url_launcher_plugin.h>
-
-void fl_register_plugins(FlPluginRegistry* registry) {
-  g_autoptr(FlPluginRegistrar) file_selector_linux_registrar =
-      fl_plugin_registry_get_registrar_for_plugin(registry, "FileSelectorPlugin");
-  file_selector_plugin_register_with_registrar(file_selector_linux_registrar);
-  g_autoptr(FlPluginRegistrar) flutter_secure_storage_linux_registrar =
-      fl_plugin_registry_get_registrar_for_plugin(registry, "FlutterSecureStorageLinuxPlugin");
-  flutter_secure_storage_linux_plugin_register_with_registrar(flutter_secure_storage_linux_registrar);
-  g_autoptr(FlPluginRegistrar) url_launcher_linux_registrar =
-      fl_plugin_registry_get_registrar_for_plugin(registry, "UrlLauncherPlugin");
-  url_launcher_plugin_register_with_registrar(url_launcher_linux_registrar);
-}

linux/flutter/generated_plugin_registrant.h

@@ -1,15 +0,0 @@
-//
-//  Generated file. Do not edit.
-//
-
-// clang-format off
-
-#ifndef GENERATED_PLUGIN_REGISTRANT_
-#define GENERATED_PLUGIN_REGISTRANT_
-
-#include <flutter_linux/flutter_linux.h>
-
-// Registers Flutter plugins.
-void fl_register_plugins(FlPluginRegistry* registry);
-
-#endif  // GENERATED_PLUGIN_REGISTRANT_

linux/flutter/generated_plugins.cmake

@@ -1,27 +0,0 @@
-#
-# Generated file, do not edit.
-#
-
-list(APPEND FLUTTER_PLUGIN_LIST
-  file_selector_linux
-  flutter_secure_storage_linux
-  url_launcher_linux
-)
-
-list(APPEND FLUTTER_FFI_PLUGIN_LIST
-  jni
-)
-
-set(PLUGIN_BUNDLED_LIBRARIES)
-
-foreach(plugin ${FLUTTER_PLUGIN_LIST})
-  add_subdirectory(flutter/ephemeral/.plugin_symlinks/${plugin}/linux plugins/${plugin})
-  target_link_libraries(${BINARY_NAME} PRIVATE ${plugin}_plugin)
-  list(APPEND PLUGIN_BUNDLED_LIBRARIES $<TARGET_FILE:${plugin}_plugin>)
-  list(APPEND PLUGIN_BUNDLED_LIBRARIES ${${plugin}_bundled_libraries})
-endforeach(plugin)
-
-foreach(ffi_plugin ${FLUTTER_FFI_PLUGIN_LIST})
-  add_subdirectory(flutter/ephemeral/.plugin_symlinks/${ffi_plugin}/linux plugins/${ffi_plugin})
-  list(APPEND PLUGIN_BUNDLED_LIBRARIES ${${ffi_plugin}_bundled_libraries})
-endforeach(ffi_plugin)

linux/runner/CMakeLists.txt

@@ -1,26 +0,0 @@
-cmake_minimum_required(VERSION 3.13)
-project(runner LANGUAGES CXX)
-
-# Define the application target. To change its name, change BINARY_NAME in the
-# top-level CMakeLists.txt, not the value here, or `flutter run` will no longer
-# work.
-#
-# Any new source files that you add to the application should be added here.
-add_executable(${BINARY_NAME}
-  "main.cc"
-  "my_application.cc"
-  "${FLUTTER_MANAGED_DIR}/generated_plugin_registrant.cc"
-)
-
-# Apply the standard set of build settings. This can be removed for applications
-# that need different build settings.
-apply_standard_settings(${BINARY_NAME})
-
-# Add preprocessor definitions for the application ID.
-add_definitions(-DAPPLICATION_ID="${APPLICATION_ID}")
-
-# Add dependency libraries. Add any application-specific dependencies here.
-target_link_libraries(${BINARY_NAME} PRIVATE flutter)
-target_link_libraries(${BINARY_NAME} PRIVATE PkgConfig::GTK)
-
-target_include_directories(${BINARY_NAME} PRIVATE "${CMAKE_SOURCE_DIR}")

linux/runner/main.cc

@@ -1,6 +0,0 @@
-#include "my_application.h"
-
-int main(int argc, char** argv) {
-  g_autoptr(MyApplication) app = my_application_new();
-  return g_application_run(G_APPLICATION(app), argc, argv);
-}

linux/runner/my_application.cc

@@ -1,153 +0,0 @@
-#include "my_application.h"
-
-#include <flutter_linux/flutter_linux.h>
-#ifdef GDK_WINDOWING_X11
-#include <gdk/gdkx.h>
-#endif
-
-#include "flutter/generated_plugin_registrant.h"
-
-struct _MyApplication {
-  GtkApplication parent_instance;
-  char** dart_entrypoint_arguments;
-};
-
-G_DEFINE_TYPE(MyApplication, my_application, GTK_TYPE_APPLICATION)
-
-// Called when first Flutter frame received.
-static void first_frame_cb(MyApplication* self, FlView* view) {
-  gtk_widget_show(gtk_widget_get_toplevel(GTK_WIDGET(view)));
-}
-
-// Implements GApplication::activate.
-static void my_application_activate(GApplication* application) {
-  MyApplication* self = MY_APPLICATION(application);
-  GtkWindow* window =
-      GTK_WINDOW(gtk_application_window_new(GTK_APPLICATION(application)));
-
-  // Use a header bar when running in GNOME as this is the common style used
-  // by applications and is the setup most users will be using (e.g. Ubuntu
-  // desktop).
-  // If running on X and not using GNOME then just use a traditional title bar
-  // in case the window manager does more exotic layout, e.g. tiling.
-  // If running on Wayland assume the header bar will work (may need changing
-  // if future cases occur).
-  gboolean use_header_bar = TRUE;
-#ifdef GDK_WINDOWING_X11
-  GdkScreen* screen = gtk_window_get_screen(window);
-  if (GDK_IS_X11_SCREEN(screen)) {
-    const gchar* wm_name = gdk_x11_screen_get_window_manager_name(screen);
-    if (g_strcmp0(wm_name, "GNOME Shell") != 0) {
-      use_header_bar = FALSE;
-    }
-  }
-#endif
-  if (use_header_bar) {
-    GtkHeaderBar* header_bar = GTK_HEADER_BAR(gtk_header_bar_new());
-    gtk_widget_show(GTK_WIDGET(header_bar));
-    gtk_header_bar_set_title(header_bar, "todo");
-    gtk_header_bar_set_show_close_button(header_bar, TRUE);
-    gtk_window_set_titlebar(window, GTK_WIDGET(header_bar));
-  } else {
-    gtk_window_set_title(window, "todo");
-  }
-
-  gtk_window_set_default_size(window, 1280, 720);
-
-  // Resolved from the hicolor icon theme, which linux/install_desktop_entry.sh
-  // populates from linux/icons/. Without this the GTK runner shows a generic
-  // placeholder in the taskbar, since Flutter never sets a window icon itself.
-  gtk_window_set_icon_name(window, "todo");
-
-  g_autoptr(FlDartProject) project = fl_dart_project_new();
-  fl_dart_project_set_dart_entrypoint_arguments(
-      project, self->dart_entrypoint_arguments);
-
-  FlView* view = fl_view_new(project);
-  GdkRGBA background_color;
-  // Background defaults to black, override it here if necessary, e.g. #00000000
-  // for transparent.
-  gdk_rgba_parse(&background_color, "#000000");
-  fl_view_set_background_color(view, &background_color);
-  gtk_widget_show(GTK_WIDGET(view));
-  gtk_container_add(GTK_CONTAINER(window), GTK_WIDGET(view));
-
-  // Show the window when Flutter renders.
-  // Requires the view to be realized so we can start rendering.
-  g_signal_connect_swapped(view, "first-frame", G_CALLBACK(first_frame_cb),
-                           self);
-  gtk_widget_realize(GTK_WIDGET(view));
-
-  fl_register_plugins(FL_PLUGIN_REGISTRY(view));
-
-  gtk_widget_grab_focus(GTK_WIDGET(view));
-}
-
-// Implements GApplication::local_command_line.
-static gboolean my_application_local_command_line(GApplication* application,
-                                                  gchar*** arguments,
-                                                  int* exit_status) {
-  MyApplication* self = MY_APPLICATION(application);
-  // Strip out the first argument as it is the binary name.
-  self->dart_entrypoint_arguments = g_strdupv(*arguments + 1);
-
-  g_autoptr(GError) error = nullptr;
-  if (!g_application_register(application, nullptr, &error)) {
-    g_warning("Failed to register: %s", error->message);
-    *exit_status = 1;
-    return TRUE;
-  }
-
-  g_application_activate(application);
-  *exit_status = 0;
-
-  return TRUE;
-}
-
-// Implements GApplication::startup.
-static void my_application_startup(GApplication* application) {
-  // MyApplication* self = MY_APPLICATION(object);
-
-  // Perform any actions required at application startup.
-
-  G_APPLICATION_CLASS(my_application_parent_class)->startup(application);
-}
-
-// Implements GApplication::shutdown.
-static void my_application_shutdown(GApplication* application) {
-  // MyApplication* self = MY_APPLICATION(object);
-
-  // Perform any actions required at application shutdown.
-
-  G_APPLICATION_CLASS(my_application_parent_class)->shutdown(application);
-}
-
-// Implements GObject::dispose.
-static void my_application_dispose(GObject* object) {
-  MyApplication* self = MY_APPLICATION(object);
-  g_clear_pointer(&self->dart_entrypoint_arguments, g_strfreev);
-  G_OBJECT_CLASS(my_application_parent_class)->dispose(object);
-}
-
-static void my_application_class_init(MyApplicationClass* klass) {
-  G_APPLICATION_CLASS(klass)->activate = my_application_activate;
-  G_APPLICATION_CLASS(klass)->local_command_line =
-      my_application_local_command_line;
-  G_APPLICATION_CLASS(klass)->startup = my_application_startup;
-  G_APPLICATION_CLASS(klass)->shutdown = my_application_shutdown;
-  G_OBJECT_CLASS(klass)->dispose = my_application_dispose;
-}
-
-static void my_application_init(MyApplication* self) {}
-
-MyApplication* my_application_new() {
-  // Set the program name to the application ID, which helps various systems
-  // like GTK and desktop environments map this running application to its
-  // corresponding .desktop file. This ensures better integration by allowing
-  // the application to be recognized beyond its binary name.
-  g_set_prgname(APPLICATION_ID);
-
-  return MY_APPLICATION(g_object_new(my_application_get_type(),
-                                     "application-id", APPLICATION_ID, "flags",
-                                     G_APPLICATION_NON_UNIQUE, nullptr));
-}

linux/runner/my_application.h

@@ -1,21 +0,0 @@
-#ifndef FLUTTER_MY_APPLICATION_H_
-#define FLUTTER_MY_APPLICATION_H_
-
-#include <gtk/gtk.h>
-
-G_DECLARE_FINAL_TYPE(MyApplication,
-                     my_application,
-                     MY,
-                     APPLICATION,
-                     GtkApplication)
-
-/**
- * my_application_new:
- *
- * Creates a new Flutter-based application.
- *
- * Returns: a new #MyApplication.
- */
-MyApplication* my_application_new();
-
-#endif  // FLUTTER_MY_APPLICATION_H_

run.sh

@@ -119,11 +119,17 @@ main() {
     command -v flutter >/dev/null 2>&1 || { err "flutter still not on PATH after install"; exit 1; }
 
     cd "${SCRIPT_DIR}"
-    flutter config --enable-linux-desktop >/dev/null
+    flutter config --enable-web >/dev/null
     log "fetching pub packages"
     flutter pub get
+
+    # The desktop app is a web build served by the local wrapper: Flutter's
+    # Linux embedder manages only ~20fps at 4K, while the same Dart code in
+    # Chrome sustains ~144fps (docs/desktop-performance-findings.md).
+    log "building the web bundle"
+    flutter build web --release
     log "launching the app"
-    exec flutter run -d linux
+    exec dart run bin/todo_desktop.dart --web-root "${SCRIPT_DIR}/build/web"
 }
 
 main "$@"