Add simulator audio support

- Run SDL from main() and place FreeRTOS in separate thread. This fixes macOS support.
- Updated GitHub Actions to publish macOS simulator build for testing, updated amd64 to x86_64 for consistent naming.

.claude/rules/CLAUDE.md

@@ -63,3 +63,7 @@ Strong success criteria let you loop independently. Weak criteria ("make it work
 ---
 
 **These guidelines are working if:** fewer unnecessary changes in diffs, fewer rewrites due to overcomplication, and clarifying questions come before implementation rather than after mistakes.
+
+For current-firmware merges, board customization retention, ESP-IDF build/flash,
+and external-app compatibility verification, also follow
+`.claude/skills/tactility-firmware-development/SKILL.md`.

.claude/skills/tactility-firmware-development/SKILL.md

@@ -0,0 +1,208 @@
+---
+name: tactility-firmware-development
+description: Use when merging current Tactility firmware, preserving local ES3C28P/ES3C35P customizations, building/flashing ESP32 firmware, or validating external apps against it.
+---
+
+# Tactility firmware development
+
+## Scope and success criteria
+
+Use this skill for firmware upgrades, especially when upstream changes the app
+loader, dashboard API, SDK export, or device model. Before editing, record the
+active branch, `git status --short`, selected `Devices/<id>`, serial port, and
+the expected device identity. Preserve user work and local board
+customizations; do not reset or overwrite a dirty tree.
+
+Success is not merely a successful flash: the board must boot, mount storage,
+return `/api/sysinfo`, expose required internal apps, and accept an external
+app rebuilt against this exact firmware.
+
+## Upgrade and customization audit
+
+1. Fetch and compare the intended upstream branch before merging. Treat
+   `upstream/main` as distinct from experimental release/IDF branches unless
+   the task explicitly asks for one of those branches.
+2. Merge without discarding local work (for example, `git merge --autostash
+   upstream/main` after inspecting status). Resolve conflicts by preserving
+   required ES3C28P and ES3C35P device definitions, partition selection,
+   display/font customizations, and product features.
+3. Compare the pre-upgrade customization commit against the resulting worktree.
+   Check new app registrations, CMake/source inclusion, settings pages,
+   web-server endpoints, and board-specific `sdkconfig` entries—not just files
+   that happen to conflict.
+4. Commit the resulting firmware customization as a focused, reviewable
+   commit after `git diff --check`.
+
+## Multi-binary external-app compatibility
+
+Upstream app packaging changed to `bin/<platform>/<binary>.elf`. The old
+`elf/<platform>.elf` archive layout produces a loader `Not executable` error.
+
+- Manifest v0.2: `bin/esp32s3/app.elf`
+- Manifest v0.3: `bin/esp32s3/<app.0.binary>.elf`
+
+When this change arrives, update the companion app tool and rebuild every app
+from a fresh SDK exported from this firmware. Do not attempt to repair a
+packaged ELF on the SD card: its layout and ABI must both be regenerated.
+
+## Build and flash
+
+Use the installed IDF 5.5 environment; host virtual environments can corrupt
+both Python dependencies and IDF tooling:
+
+```zsh
+unset VIRTUAL_ENV PYTHONPATH PYTHONHOME
+export IDF_PYTHON_ENV_PATH=/Users/adolforeyna/.espressif/python_env/idf5.5_py3.9_env
+source /Users/adolforeyna/esp/esp-idf/export.sh
+
+# Select/check the intended board before this step.
+python device.py <device-id>
+idf.py build
+idf.py -p /dev/cu.usbmodemXXXX flash
+```
+
+`Tactility/CMakeLists.txt` uses a non-configure-dependent source glob. After
+adding a new `.c`/`.cpp` file, run `idf.py reconfigure build`; otherwise a
+linker error for a newly referenced symbol may only mean CMake has not
+discovered the source file yet.
+
+## Boot and feature acceptance
+
+Capture serial at 115200 after flash or reset. Confirm the board name, SD-card
+mount, HTTP-server start, Wi-Fi address, and any feature-specific startup logs.
+Then query the resolved device:
+
+```zsh
+curl -fsS http://<ip>/api/sysinfo
+curl -fsS http://<ip>/api/apps
+```
+
+For MCP settings, verify the `McpSettings` internal app appears in `/api/apps`.
+When enabled, verify MCP stream startup logs. For a feature restored from an
+older customization, validate its registration path and persisted settings,
+not only its source files.
+
+## External-app acceptance gate
+
+Use the companion app skill's exact-firmware wrapper:
+
+```zsh
+cd /path/to/tactility_apps
+scripts/build_current_firmware_app.sh Apps/MyApp --firmware /path/to/tactility
+```
+
+Inspect the resulting tar member path, install through port-80 dashboard API,
+launch it, and read serial. Required evidence is the loader's `Loading
+.../bin/...`, an ELF entry address, `Task started`, and app-specific startup
+logs. HTTP 200 or a package simply appearing in `/api/apps` is insufficient.
+
+## Host simulator (buildsim) + web viewer
+
+The POSIX simulator runs the real firmware (LVGL, services, web server) on
+macOS/Linux with an SDL backend. On current firmware, `Main.cpp` runs SDL's
+event loop on the process main thread while FreeRTOS runs on a separate thread.
+This is required by AppKit and supports a native macOS window as well as the
+web viewer. `SDL_VIDEODRIVER=dummy` remains useful for headless automation.
+
+Code locations:
+
+- `Devices/simulator/Source/module.cpp` — display resolution + `SIM_DISPLAY_W/H`
+- `Devices/simulator/Source/drivers/sdl_display.{h,cpp}` — SDL backend
+- `Devices/simulator/Source/drivers/sdl_input.{h,cpp}` — pointer/key state +
+  web touch-injection override
+- `Tactility/Source/service/webserver/WebServerService.cpp` — `/sim` viewer,
+  `/sim/api/*` aliases, `POST /api/sim/touch`, `GET /api/screenshot?fast=`
+- `Tactility/Private/Tactility/service/webserver/WebServerService.h` — handler decls
+
+### Build and run
+
+```zsh
+# one-time host deps (outside any ESP-IDF env)
+mkdir -p /tmp/simbin && ln -sf "$(which python3)" /tmp/simbin/python
+pip3 install --break-system-packages lark pyyaml   # devicetree compiler
+
+cd /path/to/tactility
+export PATH="/tmp/simbin:$PATH"
+env -u ESP_IDF_VERSION -u IDF_PATH cmake -S . -B buildsim -DCMAKE_BUILD_TYPE=Release
+env -u ESP_IDF_VERSION -u IDF_PATH cmake --build buildsim --target Tactility -j "$(sysctl -n hw.ncpu)"
+
+# POSIX SDK for host apps (arm64)
+env -u ESP_IDF_VERSION -u IDF_PATH cmake --build buildsim --target TactilityKernel lvgl minitar minmea \
+  app-module crypt-module gps-module http-module lvgl-module lvgl-window-manager-module service-module
+env -u ESP_IDF_VERSION -u IDF_PATH python3 Buildscripts/release-sdk-posix.py /tmp/sim-sdk
+
+# release (MUST run from the firmware root: release-simulator.sh uses relative
+# version.txt / Data paths)
+sh Buildscripts/release-simulator.sh buildsim /tmp/simrun
+# Native macOS window + web API. Run this from the release directory because
+# data/ and system/ are relative to the process working directory.
+(cd /tmp/simrun && SIM_DISPLAY_W=480 SIM_DISPLAY_H=320 \
+  nohup ./Tactility > /tmp/sim_gui.log 2>&1 &)
+# For CI/headless operation, set SDL_VIDEODRIVER=dummy instead.
+curl -s --max-time 5 http://127.0.0.1/api/sysinfo | head -c 120
+```
+
+Display resolution: `SIM_DISPLAY_W/H` env (default **480x320 landscape**,
+matching on-device screenshots). ES3C35P panel is 320x480 portrait in DTS but
+presents 480x320 landscape; ES3C28P is 320x240. The chosen geometry is logged
+as `Simulator Sim display WxH`. `SDL_VIDEODRIVER=dummy` is expected to log one
+`SdlDisplay Failed to create SDL window: Couldn't find matching render
+driver` line — LVGL still renders and screenshots work. A native macOS launch
+must not emit that line.
+
+### Web viewer, touch, screenshots
+
+- `GET /sim` → 301 to `/sim/` (trailing slash required so the page's relative
+  `api/` URLs resolve under `/sim/`). Viewer polls `api/screenshot?fast=1`
+  every 500 ms, footer shows live `naturalWidth×naturalHeight`, click/tap
+  POSTs `api/sim/touch?x=&y=`.
+- `POST /api/sim/touch?x=123&y=456[&down=0|1]` (also `/sim/api/sim/touch` via
+  alias). Coordinates are LVGL logical pixels. `down=1` (default) presses and
+  **auto-releases after 1500 ms** (`SIM_TOUCH_HOLD_MS` in `sdl_input.cpp`),
+  long enough for LVGL indev polls to register a click. Simulator-only: 404 on
+  ESP32 (`#ifndef ESP_PLATFORM`).
+- `GET /api/screenshot?fast=1` (default): `lv_snapshot_take` (RGB888) → in-place
+  BGR→RGB swap → `lodepng_encode24` **to memory** → chunked HTTP. No filesystem
+  touch, ~8 ms/shot. `?fast=0` keeps the legacy `webscreenshotN.png` file path
+  (slot scan + accumulation — avoid for viewer loops).
+- lodepng include in `.cpp`: `#define LODEPNG_NO_COMPILE_CPP` before
+  `#include "src/libs/lodepng/lodepng.h"`, otherwise its C++ `std::vector`
+  overloads collide with the C declarations (`conflicting types for 'encode'`).
+- MCP includes and `settings::mcp` reads are `#ifdef ESP_PLATFORM`-gated; the
+  sim has no `McpSystem`.
+
+### Tailscale viewer
+
+```zsh
+tailscale serve --bg --set-path=/simagent http://127.0.0.1:80/
+# open: https://<node>/simagent/sim/
+```
+
+The serve target must be `/` (not `/sim`): the page resolves `api/` against
+its own directory, so at `/simagent/sim/` fetches go to `/simagent/sim/api/…`,
+which tailscale strips to `/sim/api/…` and the firmware's `/sim/api/*`
+aliases (GET+POST, registered in `startServer()`) handle. Absolute `/api/…`
+URLs would 404 at the edge (no `/api` mount there).
+
+### Simulator pitfalls
+
+- **Rebuild ≠ redeploy.** `cmake --build buildsim` updates `buildsim/` only.
+  Re-run `release-simulator.sh`, restart the process, then retest. A stale
+  `/tmp/simrun/Tactility` serves old handlers with new logs nowhere to be found.
+- **One simulator owns port 80.** Do not launch a second instance while another
+  simulator is listening: it will initialize LVGL but fail `bind/listen`, so its
+  app API and viewer target the other process. Identify the listener with
+  `lsof -nP -iTCP:80 -sTCP:LISTEN`, stop only the intended simulator, then
+  release/restart it before installing or running POSIX apps.
+- **Input is cross-thread on macOS.** SDL event pumping occurs on the real main
+  thread; LVGL and web touch injection run elsewhere. Keep all shared pointer,
+  key-queue, and touch-override state under `sdl_input.cpp`'s mutex.
+- **C array `sizeof` decay.** A helper like
+  `f(HttpServerRequest*, char uri[256])` sees `sizeof(uri) == 8`, truncating
+  `get_uri` output to 7 chars (`/api/sy`, `/sim/ap` 404s). Pass the size
+  explicitly: `f(request, buf, sizeof(buf))`.
+- **Log truncation.** `LOG_QUEUE_MESSAGE_MAX_LENGTH` is 256 (`TactilityKernel/
+  private/tactility/log_queue.h`), including color/timestamp prefix. Long URIs
+  and messages truncate — don't over-interpret a short path in the log.
+- **Auth.** The viewer and API handlers enforce `validateRequestAuth` like any
+  other endpoint; failures surface as 401/404, not viewer bugs.

.github/actions/build-simulator/action.yml

@@ -4,11 +4,8 @@ inputs:
   os_name:
     description: A descriptive name for the operating system (e.g. linux, windows)
     required: true
-  platform_name:
-    description: A descriptive name for the target platform (e.g. amd64, aarch64, etc.)
-    required: true
-  publish:
-    description: A boolean that enables publishing of artifacts
+  architecture:
+    description: A descriptive name for the target architecture (e.g. x86_64, aarch64, etc.)
     required: true
 
 runs:
@@ -48,11 +45,10 @@ runs:
       run: cmake --build buildsim --target Tactility
     - name: 'Release'
       shell: bash
-      run: Buildscripts/release-simulator.sh buildsim release/Simulator-${{ inputs.os_name }}-${{ inputs.platform_name }}
+      run: Buildscripts/release-simulator.sh buildsim release/Simulator-${{ inputs.os_name }}-${{ inputs.architecture }}
     - name: 'Upload Artifact'
       uses: actions/upload-artifact@v4
-      if: ${{ inputs.publish == 'true' }}
       with:
-        name: Simulator-${{ inputs.os_name }}-${{ inputs.platform_name }}
-        path: release/Simulator-${{ inputs.os_name }}-${{ inputs.platform_name }}
+        name: Simulator-${{ inputs.os_name }}-${{ inputs.architecture }}
+        path: release/Simulator-${{ inputs.os_name }}-${{ inputs.architecture }}
         retention-days: 30

.github/workflows/build-simulator.yml

@@ -17,8 +17,7 @@ jobs:
         uses: ./.github/actions/build-simulator
         with:
           os_name: linux
-          platform_name: amd64
-          publish: true
+          architecture: x86_64
   macOS:
     runs-on: macos-latest
     steps:
@@ -29,6 +28,4 @@ jobs:
         uses: ./.github/actions/build-simulator
         with:
           os_name: macos
-          platform_name: aarch64
-          # macOS simulator currently fails due to main thread requirement for rendering
-          publish: false
+          architecture: aarch64

.gitignore

@@ -3,6 +3,8 @@
 
 build*/
 !.github/actions/build*/
+!Buildscripts/
+!Buildscripts/release-simulator-macos-app.sh
 cmake*/
 CMakeCache.txt
 *.cbp
@@ -27,4 +29,4 @@ sdkconfig.board.*.dev
 .caveman.json
 .ai/mcp
 
-__pycache__
+__pycache__

Buildscripts/DevicetreeCompiler/tests/test_integration.py

@@ -311,11 +311,39 @@ def test_compile_missing_config():
         print("PASSED")
         return True
 
+
+def test_es3c35p_uses_current_runtime_contract():
+    print("Running test_es3c35p_uses_current_runtime_contract...")
+    repository_root = os.path.abspath(os.path.join(SCRIPT_DIR, "..", "..", ".."))
+    device_dir = os.path.join(repository_root, "Devices", "es3c35p")
+    with open(os.path.join(device_dir, "device.properties")) as f:
+        properties = f.read()
+    with open(os.path.join(device_dir, "es3c35p.dts")) as f:
+        devicetree = f.read()
+
+    requirements = [
+        ("apps.launcherAppId=tactility.launcher" in properties, "current launcher app id"),
+        ("hardware.tinyUsb=" not in properties, "no obsolete hardware.tinyUsb property"),
+        ('wifi0 {\n\t\tcompatible = "espressif,esp32-wifi-pinned";\n\t};' in devicetree,
+         "Wi-Fi enabled for web server and MCP"),
+        ('ble0 {\n\t\tcompatible = "espressif,esp32-ble";\n\t};' in devicetree,
+         "BLE node matches hardware.bluetooth=true"),
+    ]
+    missing = [description for condition, description in requirements if not condition]
+    if missing:
+        print("FAILED: " + ", ".join(missing))
+        return False
+
+    print("PASSED")
+    return True
+
+
 if __name__ == "__main__":
     tests = [
         test_compile_success,
         test_compile_invalid_dts,
         test_compile_missing_config,
+        test_es3c35p_uses_current_runtime_contract,
         test_minmax_within_range_succeeds,
         test_minmax_below_minimum_fails,
         test_minmax_above_maximum_fails,

Buildscripts/generate-launcher-background.py

@@ -0,0 +1,87 @@
+#!/usr/bin/env python3
+
+"""Convert an image to an uncompressed LVGL RGB565 launcher background."""
+
+import argparse
+import shutil
+import struct
+import subprocess
+from pathlib import Path
+
+
+LV_IMAGE_HEADER_MAGIC = 0x19
+LV_COLOR_FORMAT_RGB565 = 0x12
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser(
+        description=(
+            "Create an uncompressed LVGL .bin image for "
+            "/sdcard/tactility/launcher/background.bin. Use a square image sized "
+            "to the display's longest edge to support both orientations without scaling "
+            "(for example, 320x320 for a 320x240 display)."
+        )
+    )
+    parser.add_argument("input", type=Path, help="Source image")
+    parser.add_argument("output", type=Path, help="Destination .bin file")
+    parser.add_argument("--width", type=int, required=True, help="Output width")
+    parser.add_argument("--height", type=int, required=True, help="Output height")
+    return parser.parse_args()
+
+
+def main() -> None:
+    args = parse_args()
+    if args.width <= 0 or args.width > 65535 or args.height <= 0 or args.height > 65535:
+        raise SystemExit("width and height must be between 1 and 65535")
+
+    magick = shutil.which("magick")
+    if magick is None:
+        raise SystemExit("ImageMagick is required (the 'magick' command was not found)")
+
+    command = [
+        magick,
+        str(args.input),
+        "-resize",
+        f"{args.width}x{args.height}^",
+        "-gravity",
+        "center",
+        "-extent",
+        f"{args.width}x{args.height}",
+        "-depth",
+        "8",
+        "rgb:-",
+    ]
+    rgb888 = subprocess.run(command, check=True, stdout=subprocess.PIPE).stdout
+    expected_size = args.width * args.height * 3
+    if len(rgb888) != expected_size:
+        raise SystemExit(f"unexpected ImageMagick output: {len(rgb888)} bytes, expected {expected_size}")
+
+    rgb565 = bytearray(args.width * args.height * 2)
+    for source_offset in range(0, len(rgb888), 3):
+        r, g, b = rgb888[source_offset : source_offset + 3]
+        pixel = ((r >> 3) << 11) | ((g >> 2) << 5) | (b >> 3)
+        destination_offset = (source_offset // 3) * 2
+        struct.pack_into("<H", rgb565, destination_offset, pixel)
+
+    stride = args.width * 2
+    header = struct.pack(
+        "<BBHHHHH",
+        LV_IMAGE_HEADER_MAGIC,
+        LV_COLOR_FORMAT_RGB565,
+        0,
+        args.width,
+        args.height,
+        stride,
+        0,
+    )
+
+    args.output.parent.mkdir(parents=True, exist_ok=True)
+    args.output.write_bytes(header + rgb565)
+    print(
+        f"Wrote {args.output} ({args.width}x{args.height}, "
+        f"{len(header) + len(rgb565)} bytes, uncompressed RGB565)"
+    )
+
+
+if __name__ == "__main__":
+    main()

Buildscripts/release-simulator-macos-app.sh

@@ -0,0 +1,63 @@
+#!/bin/sh
+
+# Usage: release-simulator-macos-app.sh [builddir] [Tactility.app]
+# Example: release-simulator-macos-app.sh buildsim release/Tactility.app
+
+set -eu
+
+build_path=$1
+bundle_path=$2
+
+if [ -e "$bundle_path" ]; then
+    echo "Refusing to overwrite existing bundle: $bundle_path" >&2
+    exit 1
+fi
+
+contents_path="$bundle_path/Contents"
+resources_path="$contents_path/Resources"
+macos_path="$contents_path/MacOS"
+
+mkdir -p "$resources_path" "$macos_path"
+
+cp "$build_path/Tactility/Tactility" "$resources_path/Tactility-bin"
+cp version.txt "$resources_path/"
+cp -R Data/data "$resources_path/"
+cp -R Data/system "$resources_path/"
+
+cat > "$contents_path/Info.plist" <<'EOF'
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>CFBundleDevelopmentRegion</key>
+    <string>en</string>
+    <key>CFBundleExecutable</key>
+    <string>Tactility</string>
+    <key>CFBundleIdentifier</key>
+    <string>org.tactilityproject.simulator</string>
+    <key>CFBundleInfoDictionaryVersion</key>
+    <string>6.0</string>
+    <key>CFBundleName</key>
+    <string>Tactility</string>
+    <key>CFBundlePackageType</key>
+    <string>APPL</string>
+    <key>CFBundleShortVersionString</key>
+    <string>0.8.0-dev</string>
+    <key>CFBundleVersion</key>
+    <string>1</string>
+    <key>NSMicrophoneUsageDescription</key>
+    <string>Tactility uses the microphone when a simulator app records audio.</string>
+</dict>
+</plist>
+EOF
+
+cat > "$macos_path/Tactility" <<'EOF'
+#!/bin/sh
+set -eu
+
+resources_path="$(CDPATH= cd -- "$(dirname -- "$0")/../Resources" && pwd)"
+cd "$resources_path"
+exec "$resources_path/Tactility-bin" "$@"
+EOF
+
+chmod +x "$macos_path/Tactility" "$resources_path/Tactility-bin"

CMakeLists.txt

@@ -62,9 +62,13 @@ if (DEFINED ENV{ESP_IDF_VERSION})
     # to every target; PanicHandler.cpp branches internally per architecture.
     idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=esp_panic_handler" APPEND)
 
-    idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=read" APPEND)
-    idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=write" APPEND)
-    idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=close" APPEND)
+    # Wraps newlib's reentrant syscall stubs, not the plain read()/write()/close() newlib itself
+    # implements as thin wrappers around them. newlib's own stdio (fflush()'s buffer-flush path in particular)
+    # calls these _r stubs directly, bypassing the plain names entirely.
+    # See Modules/app-module/source/stdio_wrap.cpp's own comment for the exact call chain.
+    idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=_read_r" APPEND)
+    idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=_write_r" APPEND)
+    idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=_close_r" APPEND)
 
     idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=lv_button_create" APPEND)
     idf_build_set_property(LINK_OPTIONS "-Wl,--wrap=lv_dropdown_create" APPEND)
@@ -106,6 +110,9 @@ endif ()
 
 # Defined as regular project for PC and component for ESP
 if (NOT DEFINED ENV{ESP_IDF_VERSION})
+    if (APPLE)
+        enable_language(OBJC OBJCXX)
+    endif ()
     add_subdirectory(Tactility)
     add_subdirectory(TactilityFreeRtos)
     add_subdirectory(TactilityKernel)
@@ -133,6 +140,7 @@ if (NOT DEFINED ENV{ESP_IDF_VERSION})
     add_subdirectory(Modules/lvgl-window-manager-module)
     add_subdirectory(Drivers/gps-generic-module)
     add_subdirectory(Drivers/gps-meshtastic-module)
+    add_subdirectory(Drivers/audio-stream-module)
 
     # FreeRTOS
     set(FREERTOS_CONFIG_FILE_DIRECTORY ${PROJECT_SOURCE_DIR}/Devices/simulator/Source CACHE STRING "")

Data/data/tactility/service/webserver/settings.properties

@@ -17,7 +17,7 @@ apOpenNetwork=0
 apChannel=1
 
 # Web Server Settings
-webServerEnabled=0
+webServerEnabled=1
 webServerPort=80
 
 # HTTP Basic Authentication (optional)

Devices/es3c28p/device.properties

@@ -19,3 +19,8 @@ display.dpi=143
 lvgl.colorDepth=16
 
 storage.userDataLocation=SD
+
+# Launcher clock and full-screen wallpaper
+sdkconfig.CONFIG_LV_FONT_MONTSERRAT_48=y
+sdkconfig.CONFIG_LV_CACHE_DEF_SIZE=1048576
+sdkconfig.CONFIG_LV_IMAGE_HEADER_CACHE_DEF_CNT=16

Devices/es3c28p/es3c28p.dts

@@ -90,6 +90,7 @@
 			compatible = "everest,es8311";
 			reg = <0x18>;
 			i2s = <&i2s0>;
+			input-gain-percent = <100>;
 		};
 	};
 

Devices/es3c35p/CMakeLists.txt

@@ -0,0 +1,4 @@
+idf_component_register(
+    SRCS "source/module.cpp"
+    REQUIRES TactilityKernel
+)

Devices/es3c35p/device.properties

@@ -0,0 +1,28 @@
+general.vendor=LCDWIKI/Hosyond
+general.name=ES3C35P
+
+apps.launcherAppId=tactility.launcher
+
+hardware.target=ESP32S3
+hardware.flashSize=16MB
+hardware.spiRam=true
+hardware.spiRamMode=OCT
+hardware.spiRamSpeed=120M
+hardware.esptoolFlashFreq=120M
+hardware.bluetooth=true
+
+display.size=3.5"
+display.shape=rectangle
+display.dpi=165
+
+lvgl.colorDepth=16
+lvgl.fontSize=16
+
+storage.userDataLocation=SD
+
+dependencies.useDeprecatedHal=false
+
+# Launcher clock and full-screen wallpaper
+sdkconfig.CONFIG_LV_FONT_MONTSERRAT_48=y
+sdkconfig.CONFIG_LV_CACHE_DEF_SIZE=1048576
+sdkconfig.CONFIG_LV_IMAGE_HEADER_CACHE_DEF_CNT=16

Devices/es3c35p/devicetree.yaml

@@ -0,0 +1,6 @@
+dependencies:
+  - Platforms/platform-esp32
+  - Drivers/st77922-module
+  - Drivers/es8311-module
+  - Drivers/audio-stream-module
+dts: es3c35p.dts

Devices/es3c35p/es3c35p.dts

@@ -0,0 +1,142 @@
+/dts-v1/;
+
+#include <tactility/bindings/root.h>
+#include <tactility/bindings/esp32_adc_oneshot.h>
+#include <tactility/bindings/esp32_ble.h>
+#include <tactility/bindings/esp32_gpio.h>
+#include <tactility/bindings/esp32_i2c.h>
+#include <tactility/bindings/esp32_i2s.h>
+#include <tactility/bindings/esp32_pwm_ledc.h>
+#include <tactility/bindings/esp32_sdmmc.h>
+#include <tactility/bindings/esp32_spi.h>
+#include <tactility/bindings/esp32_wifi_pinned.h>
+#include <tactility/bindings/battery_sense.h>
+#include <tactility/bindings/gpio_hog.h>
+#include <tactility/bindings/pwm_backlight.h>
+#include <bindings/st77922.h>
+#include <bindings/st77922_touch.h>
+#include <bindings/es8311.h>
+
+/ {
+	compatible = "root";
+	model = "LCDWIKI/Hosyond ES3C35P";
+
+	wifi0 {
+		compatible = "espressif,esp32-wifi-pinned";
+	};
+
+	ble0 {
+		compatible = "espressif,esp32-ble";
+	};
+
+	gpio0 {
+		compatible = "espressif,esp32-gpio";
+		gpio-count = <49>;
+	};
+
+	/* FM8002E speaker amplifier enable, active-low on GPIO1. */
+	amp_enable {
+		compatible = "gpio-hog";
+		pin = <&gpio0 1 GPIO_FLAG_NONE>;
+		mode = <GPIO_HOG_MODE_OUTPUT_LOW>;
+	};
+
+	adc0 {
+		compatible = "espressif,esp32-adc-oneshot";
+		unit-id = <ADC_UNIT_1>;
+		clk-src = <ADC_RTC_CLK_SRC_DEFAULT>;
+		channels = <ADC_CHANNEL_7 ADC_ATTEN_DB_12 ADC_BITWIDTH_DEFAULT>;
+	};
+
+	/* BAT+ through a 200K/200K divider into GPIO8 / ADC1_CH7. */
+	battery-sense {
+		compatible = "battery-sense";
+		io-channel = <&adc0 0>;
+		reference-voltage-mv = <3300>;
+		multiplier = <2000>;
+	};
+
+	i2s0 {
+		compatible = "espressif,esp32-i2s";
+		port = <I2S_NUM_0>;
+		pin-bclk = <&gpio0 18 GPIO_FLAG_NONE>;
+		pin-ws = <&gpio0 21 GPIO_FLAG_NONE>;
+		pin-data-out = <&gpio0 15 GPIO_FLAG_NONE>;
+		pin-data-in = <&gpio0 16 GPIO_FLAG_NONE>;
+		pin-mclk = <&gpio0 17 GPIO_FLAG_NONE>;
+	};
+
+	i2c0 {
+		compatible = "espressif,esp32-i2c";
+		port = <I2C_NUM_0>;
+		clock-frequency = <400000>;
+		pin-sda = <&gpio0 38 GPIO_FLAG_NONE>;
+		pin-scl = <&gpio0 39 GPIO_FLAG_NONE>;
+
+		touch@55 {
+			compatible = "sitronix,st77922-touch";
+			reg = <0x55>;
+			x-max = <320>;
+			y-max = <480>;
+			pin-reset = <&gpio0 48 GPIO_FLAG_NONE>;
+			pin-interrupt = <&gpio0 47 GPIO_FLAG_NONE>;
+		};
+
+		es8311: es8311@18 {
+			compatible = "everest,es8311";
+			reg = <0x18>;
+			i2s = <&i2s0>;
+			input-gain-percent = <100>;
+		};
+	};
+
+	display_backlight_pwm {
+		compatible = "espressif,esp32-pwm-ledc";
+		pin = <&gpio0 41 GPIO_FLAG_NONE>;
+		period-ns = <200000>;
+		ledc-timer = <0>;
+		ledc-channel = <0>;
+	};
+
+	display_backlight {
+		compatible = "pwm-backlight";
+		status = "disabled";
+		pwm = <&display_backlight_pwm>;
+	};
+
+	spi0 {
+		compatible = "espressif,esp32-spi";
+		host = <SPI2_HOST>;
+		pin-sclk = <&gpio0 12 GPIO_FLAG_NONE>;
+		pin-mosi = <&gpio0 11 GPIO_FLAG_NONE>;
+		pin-miso = <&gpio0 13 GPIO_FLAG_NONE>;
+		pin-wp = <&gpio0 14 GPIO_FLAG_NONE>;
+		pin-hd = <&gpio0 9 GPIO_FLAG_NONE>;
+		cs-gpios = <&gpio0 10 GPIO_FLAG_NONE>;
+		/* Accommodate the driver's 1/10-frame DMA staging transfers, matching
+		 * the vendor LVGL port's full-frame refresh path. */
+		max-transfer-size = <65536>;
+
+		display@0 {
+			compatible = "sitronix,st77922";
+			horizontal-resolution = <320>;
+			vertical-resolution = <480>;
+			/* 80 MHz works in the vendor demo, but produces visible QSPI corruption on
+			 * some modules/cables. The component's 40 MHz default is reliably clean. */
+			pixel-clock-hz = <40000000>;
+			backlight = <&display_backlight>;
+		};
+	};
+
+	sdmmc0 {
+		compatible = "espressif,esp32-sdmmc";
+		pin-clk = <&gpio0 5 GPIO_FLAG_NONE>;
+		pin-cmd = <&gpio0 4 GPIO_FLAG_NONE>;
+		pin-d0 = <&gpio0 6 GPIO_FLAG_NONE>;
+		pin-d1 = <&gpio0 7 GPIO_FLAG_NONE>;
+		pin-d2 = <&gpio0 2 GPIO_FLAG_NONE>;
+		pin-d3 = <&gpio0 3 GPIO_FLAG_NONE>;
+		slot = <SDMMC_HOST_SLOT_1>;
+		bus-width = <4>;
+	};
+};

Devices/es3c35p/source/module.cpp

@@ -0,0 +1,9 @@
+#include <tactility/module.h>
+
+extern "C" {
+
+Module es3c35p_module = {
+    .name = "es3c35p"
+};
+
+}

Devices/simulator/CMakeLists.txt

@@ -21,4 +21,13 @@ if (NOT DEFINED ENV{ESP_IDF_VERSION})
 
     target_link_libraries(simulator PRIVATE ${SDL2_LIBRARIES})
 
+    if (APPLE)
+        target_sources(simulator PRIVATE Source/drivers/sdl_audio_permission.mm)
+        target_link_libraries(simulator PRIVATE "-framework AVFoundation" "-framework Foundation")
+        # The developer executable can also request recording outside an .app bundle.
+        target_link_options(simulator INTERFACE
+            "LINKER:-sectcreate,__TEXT,__info_plist,${CMAKE_CURRENT_SOURCE_DIR}/macos-info.plist")
+        set_property(TARGET Tactility APPEND PROPERTY LINK_DEPENDS "${CMAKE_CURRENT_SOURCE_DIR}/macos-info.plist")
+    endif ()
+
 endif()

Devices/simulator/Source/Main.cpp

@@ -10,13 +10,13 @@ constexpr auto* TAG = "FreeRTOS";
 
 namespace simulator {
 
-MainFunction mainFunction = nullptr;
+static MainFunction mainFunction = nullptr;
 
 void setMain(MainFunction newMainFunction) {
     mainFunction = newMainFunction;
 }
 
-static void freertosMainTask(void* parameter) {
+static void freertosMainTask(void*) {
     LOG_I(TAG, "starting app_main()");
     assert(simulator::mainFunction);
     mainFunction();

Devices/simulator/Source/Simulator.h

@@ -1,6 +1,11 @@
 #pragma once
 
 #include "Main.h"
+#include "drivers/sdl_bridge.h"
+
+#include <csignal>
+#include <pthread.h>
+#include <thread>
 
 namespace simulator {
     /** Set the function pointer of the real app_main() */
@@ -14,8 +19,23 @@ void app_main(); // ESP-IDF's main function, implemented in the application
 }
 
 int main() {
-    // Actual main function that passes on app_main() (to be executed in a FreeRTOS task) and bootstraps FreeRTOS
+    // The FreeRTOS POSIX port arms a process-wide SIGALRM timer for its tick and expects every one
+    // of its task pthreads to have all signals but SIGINT blocked.
+    // (see prvSetupSignalsAndSchedulerPolicy() in FreeRTOS-Kernel's Posix port.c)
+    // A signal-generated SIGALRM can land on any thread in the process that doesn't block it.
+    // This thread stays a plain OS thread (running the SDL loop below, never a FreeRTOS task),
+    // so without this it's eligible to catch a tick SIGALRM and freeze inside the scheduler's handler.
+    // Block the same set here, before anything else, so it never can.
+    sigset_t all_signals_except_sigint;
+    sigfillset(&all_signals_except_sigint);
+    sigdelset(&all_signals_except_sigint, SIGINT);
+    pthread_sigmask(SIG_SETMASK, &all_signals_except_sigint, nullptr);
+
+    // FreeRTOS and app_main() run on a separate thread: macOS requires SDL/Cocoa window creation,
+    // event pumping and rendering to happen on the real OS main thread, which sdl_bridge_run_main_loop()
+    // below takes over. freertosMain() never returns, so this thread is detached rather than joined.
     simulator::setMain(app_main);
-    simulator::freertosMain();
+    std::thread(simulator::freertosMain).detach();
+    sdl_bridge_run_main_loop();
     return 0;
 }

Devices/simulator/Source/drivers/sdl_audio.cpp

@@ -0,0 +1,325 @@
+// SPDX-License-Identifier: Apache-2.0
+#include "sdl_audio.h"
+#include "sdl_audio_buffer.h"
+
+#include <tactility/device.h>
+#include <tactility/driver.h>
+#include <tactility/freertos/task.h>
+#include <tactility/log.h>
+#include <tactility/module.h>
+
+#include <SDL2/SDL.h>
+#include <atomic>
+#include <cmath>
+#include <cstdlib>
+#include <cstring>
+#include <new>
+
+namespace {
+
+constexpr auto* TAG = "SdlAudio";
+constexpr uint32_t SAMPLE_RATE = 48000;
+
+struct AudioData {
+    SdlAudioBuffer buffer;
+    SemaphoreHandle_t mutex = nullptr; // task-side only; never used by the SDL callback
+    SDL_AudioDeviceID id = 0;
+    AudioCodecDirection direction;
+    std::atomic<float> volume { 100.0f };
+    std::atomic<bool> muted { false };
+    std::atomic<uint32_t> callbacks { 0 };
+};
+
+AudioData* get_data(Device* device) {
+    return static_cast<AudioData*>(device_get_driver_data(device));
+}
+
+class Lock {
+    SemaphoreHandle_t mutex;
+public:
+    explicit Lock(AudioData* data) : mutex(data->mutex) { xSemaphoreTake(mutex, portMAX_DELAY); }
+    ~Lock() { xSemaphoreGive(mutex); }
+};
+
+const char* device_name(const AudioData* data) {
+    const char* name = std::getenv(data->direction == AUDIO_CODEC_DIR_INPUT ? "SIM_AUDIO_INPUT" : "SIM_AUDIO_OUTPUT");
+    return name != nullptr && name[0] != '\0' ? name : nullptr;
+}
+
+bool available(const AudioData* data) {
+    const char* name = device_name(data);
+    if (name != nullptr && std::strcmp(name, "none") == 0) return false;
+    const int capture = data->direction == AUDIO_CODEC_DIR_INPUT;
+    const int count = SDL_GetNumAudioDevices(capture);
+    if (name == nullptr) return count > 0;
+    for (int i = 0; i < count; ++i) {
+        const char* candidate = SDL_GetAudioDeviceName(i, capture);
+        if (candidate != nullptr && std::strcmp(candidate, name) == 0) return true;
+    }
+    return false;
+}
+
+void apply_volume(AudioData* data, void* bytes, size_t size) {
+    const float gain = data->muted.load() ? 0.0f : data->volume.load() / 100.0f;
+    auto* output = static_cast<uint8_t*>(bytes);
+    for (size_t i = 0; i < size; i += sizeof(int16_t)) {
+        int16_t sample;
+        std::memcpy(&sample, output + i, sizeof(sample));
+        sample = static_cast<int16_t>(sample * gain);
+        std::memcpy(output + i, &sample, sizeof(sample));
+    }
+}
+
+void audio_callback(void* context, Uint8* stream, int length) {
+    auto* data = static_cast<AudioData*>(context);
+    const size_t count = static_cast<size_t>(length) / sizeof(int16_t);
+    if (data->direction == AUDIO_CODEC_DIR_INPUT) {
+        // Drop incoming frames when the bounded capture buffer is full. Muted capture
+        // must not leave real microphone samples queued for a later unmute.
+        if (data->muted.load()) std::memset(stream, 0, length);
+        data->buffer.write(stream, count);
+    } else {
+        const size_t copied = data->buffer.read(stream, count) * sizeof(int16_t);
+        std::memset(stream + copied, 0, length - copied); // silence on underrun
+        apply_volume(data, stream, copied);
+    }
+    data->callbacks.fetch_add(1, std::memory_order_relaxed);
+}
+
+error_t start(Device* device) {
+    const auto* config = static_cast<const SdlAudioConfig*>(device->config);
+    if (config == nullptr || (config->direction != AUDIO_CODEC_DIR_INPUT && config->direction != AUDIO_CODEC_DIR_OUTPUT)) {
+        return ERROR_INVALID_ARGUMENT;
+    }
+    if (SDL_InitSubSystem(SDL_INIT_AUDIO) != 0) {
+        LOG_E(TAG, "Cannot initialize audio: %s", SDL_GetError());
+        return ERROR_RESOURCE;
+    }
+    auto* data = new (std::nothrow) AudioData;
+    if (data == nullptr) {
+        SDL_QuitSubSystem(SDL_INIT_AUDIO);
+        return ERROR_OUT_OF_MEMORY;
+    }
+    data->direction = config->direction;
+    data->mutex = xSemaphoreCreateMutex();
+    if (data->mutex == nullptr) {
+        delete data;
+        SDL_QuitSubSystem(SDL_INIT_AUDIO);
+        return ERROR_OUT_OF_MEMORY;
+    }
+    device_set_driver_data(device, data);
+    const int capture = data->direction == AUDIO_CODEC_DIR_INPUT;
+    for (int i = 0; i < SDL_GetNumAudioDevices(capture); ++i) {
+        LOG_I(TAG, "%s device: %s", capture ? "Input" : "Output", SDL_GetAudioDeviceName(i, capture));
+    }
+    LOG_I(TAG, "%s: %s (%s)", device->name, device_name(data) != nullptr ? device_name(data) : "system default",
+        available(data) ? "available" : "unavailable");
+    return ERROR_NONE;
+}
+
+error_t open(Device* device, const AudioCodecStreamConfig* config) {
+    auto* data = get_data(device);
+    if (config == nullptr) return ERROR_INVALID_ARGUMENT;
+    if (config->direction != data->direction) return ERROR_NOT_SUPPORTED;
+    // The shared stream module performs rate/channel conversion on S16 PCM.
+    if (config->bits_per_sample != 16) return ERROR_NOT_SUPPORTED;
+    const uint8_t channels = data->direction == AUDIO_CODEC_DIR_INPUT ? 1 : 2;
+    if (config->sample_rate != SAMPLE_RATE || config->channels != channels) return ERROR_INVALID_ARGUMENT;
+    Lock lock(data);
+    if (data->id != 0) return ERROR_INVALID_STATE;
+    if (!available(data)) {
+        LOG_W(TAG, "No selected %s device available", data->direction == AUDIO_CODEC_DIR_INPUT ? "input" : "output");
+        return ERROR_NOT_SUPPORTED;
+    }
+#ifdef __APPLE__
+    // Only ask when recording is requested, and only with real macOS audio (dummy
+    // and disk backends are also useful for automated tests).
+    if (data->direction == AUDIO_CODEC_DIR_INPUT && std::strcmp(SDL_GetCurrentAudioDriver(), "coreaudio") == 0) {
+        error_t permission;
+        while ((permission = sdl_audio_microphone_permission()) == ERROR_RESOURCE_BUSY) vTaskDelay(1);
+        if (permission != ERROR_NONE) {
+            LOG_W(TAG, "Microphone permission denied; enable access in macOS Privacy & Security > Microphone");
+            return permission;
+        }
+    }
+#endif
+    SDL_AudioSpec wanted {};
+    wanted.freq = SAMPLE_RATE;
+    wanted.format = AUDIO_S16SYS;
+    wanted.channels = channels;
+    wanted.samples = 512;
+    wanted.callback = audio_callback;
+    wanted.userdata = data;
+    data->buffer.reset();
+    data->callbacks.store(0);
+    // No allowed changes: SDL converts between our fixed PCM format and the host
+    // device's format when necessary. No hardware-specific format leaks to apps.
+    data->id = SDL_OpenAudioDevice(device_name(data), data->direction == AUDIO_CODEC_DIR_INPUT, &wanted, nullptr, 0);
+    if (data->id == 0) {
+        LOG_E(TAG, "Cannot open %s: %s", device->name, SDL_GetError());
+        return ERROR_RESOURCE;
+    }
+    SDL_PauseAudioDevice(data->id, 0);
+    return ERROR_NONE;
+}
+
+error_t close(Device* device) {
+    auto* data = get_data(device);
+    Lock lock(data);
+    if (data->id != 0) {
+        // Preserve the end of short sounds. Drain is bounded even if the device has
+        // disappeared; microphone close never waits for the capture buffer to empty.
+        const TickType_t start = xTaskGetTickCount();
+        while (data->direction == AUDIO_CODEC_DIR_OUTPUT && !data->buffer.empty()
+            && xTaskGetTickCount() - start < pdMS_TO_TICKS(250)
+            && SDL_GetAudioDeviceStatus(data->id) == SDL_AUDIO_PLAYING) {
+            vTaskDelay(1);
+        }
+        SDL_CloseAudioDevice(data->id);
+        data->id = 0;
+        data->buffer.reset();
+    }
+    return ERROR_NONE;
+}
+
+error_t stop(Device* device) {
+    auto* data = get_data(device);
+    close(device);
+    vSemaphoreDelete(data->mutex);
+    delete data;
+    device_set_driver_data(device, nullptr);
+    SDL_QuitSubSystem(SDL_INIT_AUDIO);
+    return ERROR_NONE;
+}
+
+error_t transfer(Device* device, void* destination, const void* source, size_t size, size_t* transferred, TickType_t timeout, bool capture) {
+    if (transferred != nullptr) *transferred = 0;
+    auto* data = get_data(device);
+    if ((data->direction == AUDIO_CODEC_DIR_INPUT) != capture) return ERROR_NOT_SUPPORTED;
+    const size_t frame_size = sizeof(int16_t) * (capture ? 1 : 2);
+    if (size % frame_size != 0 || (size != 0 && (capture ? destination == nullptr : source == nullptr))) return ERROR_INVALID_ARGUMENT;
+    Lock lock(data);
+    if (data->id == 0) return ERROR_INVALID_STATE;
+    const TickType_t start = xTaskGetTickCount();
+    TickType_t last_callback = start;
+    uint32_t callbacks = data->callbacks.load();
+    size_t done = 0;
+    error_t result = ERROR_NONE;
+    while (done < size) {
+        if (SDL_GetAudioDeviceStatus(data->id) != SDL_AUDIO_PLAYING) {
+            result = ERROR_RESOURCE;
+            break;
+        }
+        const size_t count = (size - done) / sizeof(int16_t);
+        const size_t copied = capture
+            ? data->buffer.read(static_cast<uint8_t*>(destination) + done, count)
+            : data->buffer.write(static_cast<const uint8_t*>(source) + done, count);
+        done += copied * sizeof(int16_t);
+        if (done == size) break;
+        const TickType_t now = xTaskGetTickCount();
+        if (timeout != portMAX_DELAY && now - start >= timeout) {
+            result = ERROR_TIMEOUT;
+            break;
+        }
+        const uint32_t current_callbacks = data->callbacks.load();
+        if (current_callbacks != callbacks) {
+            callbacks = current_callbacks;
+            last_callback = now;
+        } else if (now - last_callback >= pdMS_TO_TICKS(2000)) {
+            // A stopped backend must not strand an infinite-timeout caller or a
+            // concurrent Settings disable waiting for that caller to finish.
+            result = ERROR_RESOURCE;
+            break;
+        }
+        vTaskDelay(1);
+    }
+    if (capture) apply_volume(data, destination, done);
+    if (transferred != nullptr) *transferred = done;
+    return result;
+}
+
+error_t read(Device* device, void* destination, size_t size, size_t* count, TickType_t timeout) {
+    return transfer(device, destination, nullptr, size, count, timeout, true);
+}
+
+error_t write(Device* device, const void* source, size_t size, size_t* count, TickType_t timeout) {
+    return transfer(device, nullptr, source, size, count, timeout, false);
+}
+
+error_t set_volume(Device* device, AudioCodecDirection direction, float volume) {
+    auto* data = get_data(device);
+    if (direction != data->direction) return ERROR_NOT_SUPPORTED;
+    if (!std::isfinite(volume) || volume < 0.0f || volume > 100.0f) return ERROR_INVALID_ARGUMENT;
+    data->volume.store(volume);
+    return ERROR_NONE;
+}
+
+error_t get_volume(Device* device, AudioCodecDirection direction, float* volume) {
+    auto* data = get_data(device);
+    if (direction != data->direction) return ERROR_NOT_SUPPORTED;
+    *volume = data->volume.load();
+    return ERROR_NONE;
+}
+
+error_t set_mute(Device* device, AudioCodecDirection direction, bool muted) {
+    auto* data = get_data(device);
+    if (direction != data->direction) return ERROR_NOT_SUPPORTED;
+    data->muted.store(muted);
+    return ERROR_NONE;
+}
+
+error_t get_mute(Device* device, AudioCodecDirection direction, bool* muted) {
+    auto* data = get_data(device);
+    if (direction != data->direction) return ERROR_NOT_SUPPORTED;
+    *muted = data->muted.load();
+    return ERROR_NONE;
+}
+
+error_t get_rate(Device* device, AudioCodecDirection direction, uint32_t* rate) {
+    if (direction != get_data(device)->direction) return ERROR_NOT_SUPPORTED;
+    *rate = SAMPLE_RATE;
+    return ERROR_NONE;
+}
+
+error_t get_channels(Device* device, AudioCodecDirection direction, uint8_t* channels) {
+    if (direction != get_data(device)->direction) return ERROR_NOT_SUPPORTED;
+    *channels = direction == AUDIO_CODEC_DIR_INPUT ? 1 : 2;
+    return ERROR_NONE;
+}
+
+error_t get_capabilities(Device* device, AudioCodecDirection* direction) {
+    auto* data = get_data(device);
+    if (!available(data)) return ERROR_NOT_SUPPORTED;
+    *direction = data->direction;
+    return ERROR_NONE;
+}
+
+const AudioCodecApi api = {
+    .open = open,
+    .close = close,
+    .read = read,
+    .write = write,
+    .set_volume = set_volume,
+    .get_volume = get_volume,
+    .set_mute = set_mute,
+    .get_mute = get_mute,
+    .get_native_sample_rate = get_rate,
+    .get_native_channels = get_channels,
+    .get_capabilities = get_capabilities,
+    .get_input_gain_multiplier = nullptr,
+};
+
+} // namespace
+
+extern "C" Module simulator_module;
+
+Driver sdl_audio_driver = {
+    .name = "sdl-audio",
+    .compatible = (const char*[]) { "tactility,sdl-audio", nullptr },
+    .start_device = start,
+    .stop_device = stop,
+    .api = &api,
+    .device_type = &AUDIO_CODEC_TYPE,
+    .owner = &simulator_module,
+    .internal = nullptr,
+};

Devices/simulator/Source/drivers/sdl_audio.h

@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/drivers/audio_codec.h>
+
+struct SdlAudioConfig {
+    AudioCodecDirection direction;
+};
+
+#ifdef __APPLE__
+// Nonblocking: ERROR_RESOURCE_BUSY means that the user has not answered the prompt yet.
+error_t sdl_audio_microphone_permission();
+#endif

Devices/simulator/Source/drivers/sdl_audio_buffer.h

@@ -0,0 +1,52 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <algorithm>
+#include <array>
+#include <atomic>
+#include <cstdint>
+#include <cstring>
+
+// Single producer / single consumer. The SDL callback is a native thread: it must never
+// allocate, block, log, or call FreeRTOS. Unsigned counters also work across wraparound.
+class SdlAudioBuffer {
+    static constexpr uint32_t CAPACITY = 16384; // samples; ~171 ms of 48 kHz stereo
+    std::array<int16_t, CAPACITY> samples {};
+    std::atomic<uint32_t> read_position { 0 };
+    std::atomic<uint32_t> write_position { 0 };
+
+public:
+    size_t write(const void* source, size_t count) {
+        const uint32_t write = write_position.load(std::memory_order_relaxed);
+        const uint32_t read = read_position.load(std::memory_order_acquire);
+        count = std::min(count, static_cast<size_t>(CAPACITY - (write - read)));
+        const size_t first = std::min(count, static_cast<size_t>(CAPACITY - write % CAPACITY));
+        const auto* bytes = static_cast<const uint8_t*>(source);
+        std::memcpy(samples.data() + write % CAPACITY, bytes, first * sizeof(int16_t));
+        std::memcpy(samples.data(), bytes + first * sizeof(int16_t), (count - first) * sizeof(int16_t));
+        write_position.store(write + count, std::memory_order_release);
+        return count;
+    }
+
+    size_t read(void* destination, size_t count) {
+        const uint32_t read = read_position.load(std::memory_order_relaxed);
+        const uint32_t write = write_position.load(std::memory_order_acquire);
+        count = std::min(count, static_cast<size_t>(write - read));
+        const size_t first = std::min(count, static_cast<size_t>(CAPACITY - read % CAPACITY));
+        auto* bytes = static_cast<uint8_t*>(destination);
+        std::memcpy(bytes, samples.data() + read % CAPACITY, first * sizeof(int16_t));
+        std::memcpy(bytes + first * sizeof(int16_t), samples.data(), (count - first) * sizeof(int16_t));
+        read_position.store(read + count, std::memory_order_release);
+        return count;
+    }
+
+    bool empty() const {
+        return read_position.load(std::memory_order_acquire) == write_position.load(std::memory_order_acquire);
+    }
+
+    // Only while the SDL device is closed and no caller is doing I/O.
+    void reset() {
+        read_position.store(0);
+        write_position.store(0);
+    }
+};

Devices/simulator/Source/drivers/sdl_audio_permission.mm

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: Apache-2.0
+#include "sdl_audio.h"
+
+#import <AVFoundation/AVFoundation.h>
+#include <atomic>
+
+error_t sdl_audio_microphone_permission() {
+    @autoreleasepool {
+        switch ([AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeAudio]) {
+            case AVAuthorizationStatusAuthorized:
+                return ERROR_NONE;
+            case AVAuthorizationStatusDenied:
+            case AVAuthorizationStatusRestricted:
+                return ERROR_NOT_ALLOWED;
+            case AVAuthorizationStatusNotDetermined: {
+                static std::atomic<bool> requested { false };
+                if (!requested.exchange(true)) {
+                    [AVCaptureDevice requestAccessForMediaType:AVMediaTypeAudio completionHandler:^(BOOL granted) {
+                        requested.store(false);
+                    }];
+                }
+                return ERROR_RESOURCE_BUSY;
+            }
+        }
+        return ERROR_NOT_ALLOWED;
+    }
+}

Devices/simulator/Source/drivers/sdl_bridge.cpp

@@ -0,0 +1,64 @@
+// SPDX-License-Identifier: Apache-2.0
+#include "sdl_bridge.h"
+#include "sdl_input.h"
+
+#include <tactility/error.h>
+
+#include <chrono>
+#include <condition_variable>
+#include <mutex>
+
+namespace {
+
+struct PresentJob {
+    Device* device;
+    void* internal;
+    int32_t x_start;
+    int32_t y_start;
+    int32_t x_end;
+    int32_t y_end;
+    const void* color_data;
+    error_t result;
+};
+
+std::mutex job_mutex;
+std::condition_variable job_ready_cv;
+std::condition_variable job_done_cv;
+bool job_pending = false;
+bool job_done = false;
+PresentJob pending_job;
+
+}
+
+error_t sdl_bridge_present(Device* device, void* internal, int32_t x_start, int32_t y_start, int32_t x_end, int32_t y_end, const void* color_data) {
+    std::unique_lock<std::mutex> lock(job_mutex);
+
+    pending_job = { device, internal, x_start, y_start, x_end, y_end, color_data, ERROR_NONE };
+    job_pending = true;
+    job_done = false;
+    job_ready_cv.notify_one();
+
+    job_done_cv.wait(lock, [] { return job_done; });
+    return pending_job.result;
+}
+
+void sdl_bridge_run_main_loop() {
+    while (true) {
+        sdl_input_pump();
+
+        std::unique_lock<std::mutex> lock(job_mutex);
+        if (job_ready_cv.wait_for(lock, std::chrono::milliseconds(1), [] { return job_pending; })) {
+            PresentJob job = pending_job;
+            lock.unlock();
+
+            job.result = sdl_display_execute_draw_bitmap(job.device, job.internal, job.x_start, job.y_start, job.x_end, job.y_end, job.color_data);
+
+            lock.lock();
+            pending_job.result = job.result;
+            job_pending = false;
+            job_done = true;
+            lock.unlock();
+            job_done_cv.notify_one();
+        }
+    }
+}

Devices/simulator/Source/drivers/sdl_bridge.h

@@ -0,0 +1,40 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/error.h>
+
+#include <stdint.h>
+
+struct Device;
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Runs forever, pumping SDL input and executing display present jobs submitted via
+ * sdl_bridge_present(). Must be called exactly once, from the real OS main thread: macOS requires
+ * SDL/Cocoa window creation, event pumping and rendering to happen there, but FreeRTOS tasks
+ * (including the lvgl task that owns display flush and indev polling) run on separate pthreads
+ * spawned by the FreeRTOS POSIX port, not on that thread.
+ */
+void sdl_bridge_run_main_loop(void);
+
+/**
+ * @brief Hands a display flush off to the main thread and blocks until it has finished copying
+ * the pixel data out (see sdl_display_execute_draw_bitmap() in sdl_display.cpp). Called from the
+ * lvgl task. Must block: the caller's pixel buffer is single-buffered and gets reused as soon as
+ * this returns.
+ */
+error_t sdl_bridge_present(struct Device* device, void* internal, int32_t x_start, int32_t y_start, int32_t x_end, int32_t y_end, const void* color_data);
+
+/**
+ * @brief Implemented in sdl_display.cpp: the actual SDL work behind a display flush (lazy window
+ * init on first call, SDL_UpdateTexture, present). Only ever called from sdl_bridge_run_main_loop()
+ * on the main thread.
+ */
+error_t sdl_display_execute_draw_bitmap(struct Device* device, void* internal, int32_t x_start, int32_t y_start, int32_t x_end, int32_t y_end, const void* color_data);
+
+#ifdef __cplusplus
+}
+#endif

Devices/simulator/Source/drivers/sdl_display.cpp

@@ -1,5 +1,6 @@
 // SPDX-License-Identifier: Apache-2.0
 #include "sdl_display.h"
+#include "sdl_bridge.h"
 
 #include <tactility/device.h>
 #include <tactility/driver.h>
@@ -141,8 +142,10 @@ static bool sdl_display_lazy_init(Device* device, SdlDisplayInternal* internal)
     return true;
 }
 
-static error_t sdl_display_draw_bitmap(Device* device, int32_t x_start, int32_t y_start, int32_t x_end, int32_t y_end, const void* color_data) {
-    auto* internal = static_cast<SdlDisplayInternal*>(device_get_driver_data(device));
+// Only ever called from sdl_bridge_run_main_loop() on the real main thread - required for
+// SDL/Cocoa window creation and rendering on macOS.
+error_t sdl_display_execute_draw_bitmap(Device* device, void* internal_ptr, int32_t x_start, int32_t y_start, int32_t x_end, int32_t y_end, const void* color_data) {
+    auto* internal = static_cast<SdlDisplayInternal*>(internal_ptr);
 
     if (internal->init_failed) {
         return ERROR_RESOURCE;
@@ -166,6 +169,16 @@ static error_t sdl_display_draw_bitmap(Device* device, int32_t x_start, int32_t
     return ERROR_NONE;
 }
 
+static error_t sdl_display_draw_bitmap(Device* device, int32_t x_start, int32_t y_start, int32_t x_end, int32_t y_end, const void* color_data) {
+    auto* internal = static_cast<SdlDisplayInternal*>(device_get_driver_data(device));
+
+    if (internal->init_failed) {
+        return ERROR_RESOURCE;
+    }
+
+    return sdl_bridge_present(device, internal, x_start, y_start, x_end, y_end, color_data);
+}
+
 static enum DisplayColorFormat sdl_display_get_color_format(Device*) {
     return DISPLAY_COLOR_FORMAT_RGB565;
 }

Devices/simulator/Source/drivers/sdl_input.cpp

@@ -7,13 +7,48 @@
 #include <SDL2/SDL.h>
 
 #include <cstdlib>
+#include <mutex>
 
 namespace {
 
 constexpr size_t KEY_QUEUE_CAPACITY = 32;
 
+// Written by sdl_input_pump() on the real main thread, read by sdl_input_get_pointer_state()/
+// sdl_input_pop_key()/sdl_input_has_queued_key() on the lvgl task.
+std::mutex state_mutex;
+
 SdlPointerState pointer_state = { 0, 0, false };
 
+} // namespace
+
+// Web touch-injection override (headless sim viewer). Guarded by tick count so
+// a press auto-releases even if the viewer never sends the release event.
+// File-scope (not anonymous namespace): the extern "C" setters below must be
+// visible to the linker for WebServerService's touch endpoint.
+bool touch_override_active = false;
+SdlPointerState touch_override = { 0, 0, false };
+uint32_t touch_override_until_tick = 0;
+#define SIM_TOUCH_HOLD_MS 1500
+
+extern "C" void sdl_input_set_touch_override(int32_t x, int32_t y, bool pressed) {
+    std::lock_guard<std::mutex> lock(state_mutex);
+    touch_override.x = x;
+    touch_override.y = y;
+    touch_override.pressed = pressed;
+    touch_override_active = pressed;
+    if (pressed) {
+        touch_override_until_tick = SDL_GetTicks() + SIM_TOUCH_HOLD_MS;
+    }
+}
+
+extern "C" void sdl_input_clear_touch_override(void) {
+    std::lock_guard<std::mutex> lock(state_mutex);
+    touch_override_active = false;
+    touch_override.pressed = false;
+}
+
+namespace {
+
 uint32_t key_queue[KEY_QUEUE_CAPACITY];
 size_t key_queue_head = 0;
 size_t key_queue_count = 0;
@@ -70,65 +105,92 @@ uint32_t keycode_to_key(SDL_Keycode sdl_key, bool shift) {
     }
 }
 
-}
+} // namespace
 
 void sdl_input_pump() {
-    if (!text_input_started) {
-        SDL_StartTextInput();
-        text_input_started = true;
+    // exit() must run with state_mutex unlocked: it never returns, so a lock_guard held across it
+    // would never release the mutex, hanging any other thread that later calls into this file's
+    // other functions (all of which lock state_mutex) while exit() tears the process down.
+    bool quit_requested = false;
+
+    {
+        std::lock_guard<std::mutex> lock(state_mutex);
+
+        if (!text_input_started) {
+            SDL_StartTextInput();
+            text_input_started = true;
+        }
+
+        SDL_Event event;
+        while (SDL_PollEvent(&event)) {
+            switch (event.type) {
+                case SDL_MOUSEMOTION:
+                    set_pointer_position(event.motion.x, event.motion.y);
+                    break;
+                case SDL_MOUSEBUTTONDOWN:
+                    if (event.button.button == SDL_BUTTON_LEFT) {
+                        // event.button.x/y can be stale immediately after a window resize (an
+                        // SDL/X11 event-queue quirk - confirmed by comparing against a live
+                        // SDL_GetWindowSize() at the same instant). SDL_GetMouseState() queries the
+                        // OS for the current pointer position directly, sidestepping that entirely.
+                        int live_x, live_y;
+                        SDL_GetMouseState(&live_x, &live_y);
+                        set_pointer_position(live_x, live_y);
+                        pointer_state.pressed = true;
+                    }
+                    break;
+                case SDL_MOUSEBUTTONUP:
+                    if (event.button.button == SDL_BUTTON_LEFT) {
+                        pointer_state.pressed = false;
+                    }
+                    break;
+                case SDL_KEYDOWN:
+                    push_key(keycode_to_key(event.key.keysym.sym, (event.key.keysym.mod & KMOD_SHIFT) != 0));
+                    break;
+                case SDL_TEXTINPUT:
+                    // ASCII only (first byte of event.text.text) - sufficient for a simulator keyboard.
+                    push_key(static_cast<uint8_t>(event.text.text[0]));
+                    break;
+                case SDL_WINDOWEVENT:
+                    // Resizing doesn't change what LVGL last rendered, only how large it should
+                    // appear - re-present the existing frame at the new scale immediately, rather
+                    // than leaving stale-looking content on screen until the next LVGL-driven flush.
+                    if (event.window.event == SDL_WINDOWEVENT_SIZE_CHANGED) {
+                        sdl_display_present_now();
+                    }
+                    break;
+                case SDL_QUIT:
+                    quit_requested = true;
+                    break;
+                default:
+                    break;
+            }
+        }
     }
 
-    SDL_Event event;
-    while (SDL_PollEvent(&event)) {
-        switch (event.type) {
-            case SDL_MOUSEMOTION:
-                set_pointer_position(event.motion.x, event.motion.y);
-                break;
-            case SDL_MOUSEBUTTONDOWN:
-                if (event.button.button == SDL_BUTTON_LEFT) {
-                    // event.button.x/y can be stale immediately after a window resize (an
-                    // SDL/X11 event-queue quirk - confirmed by comparing against a live
-                    // SDL_GetWindowSize() at the same instant). SDL_GetMouseState() queries the
-                    // OS for the current pointer position directly, sidestepping that entirely.
-                    int live_x, live_y;
-                    SDL_GetMouseState(&live_x, &live_y);
-                    set_pointer_position(live_x, live_y);
-                    pointer_state.pressed = true;
-                }
-                break;
-            case SDL_MOUSEBUTTONUP:
-                if (event.button.button == SDL_BUTTON_LEFT) {
-                    pointer_state.pressed = false;
-                }
-                break;
-            case SDL_KEYDOWN:
-                push_key(keycode_to_key(event.key.keysym.sym, (event.key.keysym.mod & KMOD_SHIFT) != 0));
-                break;
-            case SDL_TEXTINPUT:
-                // ASCII only (first byte of event.text.text) - sufficient for a simulator keyboard.
-                push_key(static_cast<uint8_t>(event.text.text[0]));
-                break;
-            case SDL_WINDOWEVENT:
-                // Resizing doesn't change what LVGL last rendered, only how large it should
-                // appear - re-present the existing frame at the new scale immediately, rather
-                // than leaving stale-looking content on screen until the next LVGL-driven flush.
-                if (event.window.event == SDL_WINDOWEVENT_SIZE_CHANGED) {
-                    sdl_display_present_now();
-                }
-                break;
-            case SDL_QUIT:
-                exit(0);
-            default:
-                break;
-        }
+    if (quit_requested) {
+        exit(0);
     }
 }
 
 void sdl_input_get_pointer_state(SdlPointerState* out_state) {
+    std::lock_guard<std::mutex> lock(state_mutex);
+    if (touch_override_active) {
+        // Auto-release: viewer sends press only; LVGL needs press then release
+        // to register a click. Hold long enough for several indev polls.
+        if ((int32_t)(SDL_GetTicks() - touch_override_until_tick) >= 0) {
+            touch_override_active = false;
+            touch_override.pressed = false;
+        } else {
+            *out_state = touch_override;
+            return;
+        }
+    }
     *out_state = pointer_state;
 }
 
 bool sdl_input_pop_key(uint32_t* out_key) {
+    std::lock_guard<std::mutex> lock(state_mutex);
     if (key_queue_count == 0) {
         return false;
     }
@@ -139,5 +201,6 @@ bool sdl_input_pop_key(uint32_t* out_key) {
 }
 
 bool sdl_input_has_queued_key() {
+    std::lock_guard<std::mutex> lock(state_mutex);
     return key_queue_count > 0;
 }

Devices/simulator/Source/drivers/sdl_input.h

@@ -19,9 +19,9 @@ struct SdlPointerState {
 
 /**
  * @brief Drains all pending SDL events exactly once, updating the pointer state and key queue
- * below. Safe to call from both the sdl-pointer and sdl-keyboard drivers' polling functions:
- * SDL_PollEvent() drains a single global queue, so whichever driver is polled first on a given
- * LVGL indev tick pumps events for both.
+ * below. Must be called only from the real OS main thread (sdl_bridge_run_main_loop()): SDL
+ * requires event pumping to happen there on macOS. The getters below are safe to call from a
+ * different thread (the lvgl task, via sdl-pointer/sdl-keyboard's polling functions).
  */
 void sdl_input_pump(void);
 
@@ -42,6 +42,16 @@ bool sdl_input_pop_key(uint32_t* out_key);
  */
 bool sdl_input_has_queued_key(void);
 
+/**
+ * @brief Web-injected touch override (for headless sim viewer without SDL window).
+ * When active, sdl_pointer_get_touched_points() reports this state instead of
+ * the SDL mouse state. Coordinates are in LVGL logical pixels (e.g. 640x480).
+ * Pass pressed=false to release. Auto-releases after SIM_TOUCH_HOLD_MS unless
+ * refreshed (tap = press, wait, release handled by the web viewer).
+ */
+void sdl_input_set_touch_override(int32_t x, int32_t y, bool pressed);
+void sdl_input_clear_touch_override(void);
+
 #ifdef __cplusplus
 }
 #endif

Devices/simulator/Source/drivers/sdl_keyboard.cpp

@@ -16,8 +16,6 @@ static error_t stop(Device*) { return ERROR_NONE; }
 // region KeyboardApi
 
 static error_t sdl_keyboard_read_key(Device*, KeyboardKeyData* data) {
-    sdl_input_pump();
-
     uint32_t key = 0;
     if (sdl_input_pop_key(&key)) {
         data->key = key;

Devices/simulator/Source/drivers/sdl_pointer.cpp

@@ -16,7 +16,6 @@ static error_t stop(Device*) { return ERROR_NONE; }
 // region PointerApi
 
 static error_t sdl_pointer_read_data(Device*, TickType_t) {
-    sdl_input_pump();
     return ERROR_NONE;
 }
 

Devices/simulator/Source/module.cpp

@@ -1,4 +1,5 @@
 #include "drivers/sdl_display.h"
+#include "drivers/sdl_audio.h"
 
 #include <tactility/device.h>
 #include <tactility/device_listener.h>
@@ -16,11 +17,13 @@ extern "C" {
 extern Driver sdl_display_driver;
 extern Driver sdl_pointer_driver;
 extern Driver sdl_keyboard_driver;
+extern Driver sdl_audio_driver;
 
 static Driver* const simulator_drivers[] = {
     &sdl_display_driver,
     &sdl_pointer_driver,
     &sdl_keyboard_driver,
+    &sdl_audio_driver,
     nullptr
 };
 
@@ -29,10 +32,35 @@ static Driver* const simulator_drivers[] = {
 // These devices have no real bus to attach to (SDL has no notion of one), but every non-root
 // device is still expected to have a parent (see Device::parent) - they're parented to root once
 // it's available below.
-static const SdlDisplayConfig sdl_display_config = { 640, 480 };
+// Display resolution is overridable at runtime via SIM_DISPLAY_W/H env vars
+// so the sim can match real hardware (e.g. ES3C35P 3.5" = 320x480 portrait,
+// ES3C28P 2.8" = 320x240 landscape). Defaults to 640x480.
+static uint16_t sim_display_width(void) {
+    const char* w = getenv("SIM_DISPLAY_W");
+    if (w != nullptr) {
+        long v = atol(w);
+        if (v >= 120 && v <= 2048) return (uint16_t)v;
+    }
+    return 480;
+}
+
+static uint16_t sim_display_height(void) {
+    const char* h = getenv("SIM_DISPLAY_H");
+    if (h != nullptr) {
+        long v = atol(h);
+        if (v >= 120 && v <= 2048) return (uint16_t)v;
+    }
+    return 320;
+}
+
+static SdlDisplayConfig sdl_display_config = { 480, 320 };
 static Device sdl_display_device {};
 static Device sdl_pointer_device {};
 static Device sdl_keyboard_device {};
+static Device sdl_speaker_device {};
+static Device sdl_microphone_device {};
+static const SdlAudioConfig sdl_speaker_config { AUDIO_CODEC_DIR_OUTPUT };
+static const SdlAudioConfig sdl_microphone_config { AUDIO_CODEC_DIR_INPUT };
 
 static bool construct_add_start(Device* device, Device* parent, const char* name, const void* config, const char* compatible) {
     device->address = 0;
@@ -81,9 +109,15 @@ static void on_root_started(Device* device, DeviceEvent event, void* context) {
         return;
     }
 
+    sdl_display_config.horizontal_resolution = sim_display_width();
+    sdl_display_config.vertical_resolution = sim_display_height();
+    LOG_I(TAG, "Sim display %dx%d (SIM_DISPLAY_W/H override, default 480x320 landscape)",
+        sdl_display_config.horizontal_resolution, sdl_display_config.vertical_resolution);
     construct_add_start(&sdl_display_device, device, "display0", &sdl_display_config, "tactility,sdl-display");
     construct_add_start(&sdl_pointer_device, device, "pointer0", nullptr, "tactility,sdl-pointer");
     construct_add_start(&sdl_keyboard_device, device, "keyboard0", nullptr, "tactility,sdl-keyboard");
+    construct_add_start(&sdl_speaker_device, device, "speaker0", &sdl_speaker_config, "tactility,sdl-audio");
+    construct_add_start(&sdl_microphone_device, device, "microphone0", &sdl_microphone_config, "tactility,sdl-audio");
 }
 
 extern "C" {

Devices/simulator/devicetree.yaml

@@ -1,3 +1,4 @@
 dependencies:
   - Platforms/platform-posix
+  - Drivers/audio-stream-module
 dts: simulator.dts

Devices/simulator/macos-info.plist

@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
+<plist version="1.0">
+<dict>
+    <key>CFBundleIdentifier</key>
+    <string>org.tactilityproject.simulator</string>
+    <key>CFBundleName</key>
+    <string>Tactility</string>
+    <key>NSMicrophoneUsageDescription</key>
+    <string>Tactility uses the microphone when a simulator app records audio.</string>
+</dict>
+</plist>

Devices/simulator/tests/CMakeLists.txt

@@ -0,0 +1,14 @@
+add_executable(SimulatorAudioTests EXCLUDE_FROM_ALL
+    audio.cpp
+    ../Source/drivers/sdl_audio.cpp
+)
+target_include_directories(SimulatorAudioTests PRIVATE ${DOCTESTINC} ../Source/drivers)
+target_link_libraries(SimulatorAudioTests PRIVATE TactilityKernel platform-posix audio-stream-module SDL2-static)
+if (APPLE)
+    target_sources(SimulatorAudioTests PRIVATE ../Source/drivers/sdl_audio_permission.mm)
+    target_link_libraries(SimulatorAudioTests PRIVATE "-framework AVFoundation" "-framework Foundation")
+endif ()
+add_test(NAME SimulatorAudioTests COMMAND SimulatorAudioTests)
+set_tests_properties(SimulatorAudioTests PROPERTIES TIMEOUT 30 ENVIRONMENT "SDL_AUDIODRIVER=dummy;SIM_AUDIO_INPUT=;SIM_AUDIO_OUTPUT=")
+add_test(NAME SimulatorAudioPcmTests COMMAND SimulatorAudioTests --no-skip "--test-case=disk PCM*")
+set_tests_properties(SimulatorAudioPcmTests PROPERTIES TIMEOUT 30 ENVIRONMENT "SDL_AUDIODRIVER=disk;SIM_AUDIO_INPUT=;SIM_AUDIO_OUTPUT=")

Devices/simulator/tests/audio.cpp

@@ -0,0 +1,301 @@
+// SPDX-License-Identifier: Apache-2.0
+#define DOCTEST_CONFIG_IMPLEMENT
+#include "doctest.h"
+#include "sdl_audio.h"
+#include "sdl_audio_buffer.h"
+
+#include <tactility/device.h>
+#include <tactility/driver.h>
+#include <tactility/drivers/audio_stream.h>
+#include <tactility/freertos/task.h>
+#include <tactility/kernel_init.h>
+
+#include <SDL2/SDL.h>
+#include <algorithm>
+#include <cmath>
+#include <cstdlib>
+#include <cstdio>
+#include <fstream>
+#include <unistd.h>
+#include <vector>
+
+extern Driver sdl_audio_driver;
+extern "C" {
+extern Module platform_posix_module;
+extern Module audio_stream_module;
+extern Device audio_stream_device;
+static Driver* const drivers[] = { &sdl_audio_driver, nullptr };
+Module simulator_module = { .name = "simulator-audio-test", .drivers = drivers };
+}
+
+static const SdlAudioConfig output_config { AUDIO_CODEC_DIR_OUTPUT };
+static const SdlAudioConfig input_config { AUDIO_CODEC_DIR_INPUT };
+static Device speaker { .name = "speaker-test", .config = &output_config };
+static Device microphone { .name = "microphone-test", .config = &input_config };
+
+struct Stream {
+    AudioStreamHandle handle = nullptr;
+    ~Stream() { if (handle != nullptr) audio_stream_close(handle); }
+};
+
+TEST_CASE("bounded PCM buffer preserves data across wrap and overflow") {
+    SdlAudioBuffer buffer;
+    std::vector<int16_t> input(20000);
+    for (size_t i = 0; i < input.size(); ++i) input[i] = static_cast<int16_t>(i);
+    std::vector<int16_t> output(20000, -1);
+    CHECK(buffer.read(output.data(), output.size()) == 0);
+    REQUIRE(buffer.write(input.data(), input.size()) == 16384);
+    CHECK(buffer.write(input.data(), 2) == 0);
+    REQUIRE(buffer.read(output.data(), 10000) == 10000);
+    CHECK(std::equal(output.begin(), output.begin() + 10000, input.begin()));
+    REQUIRE(buffer.write(input.data(), 10000) == 10000);
+    REQUIRE(buffer.read(output.data(), output.size()) == 16384);
+    CHECK(std::equal(output.begin(), output.begin() + 6384, input.begin() + 10000));
+    CHECK(std::equal(output.begin() + 6384, output.begin() + 16384, input.begin()));
+    CHECK(buffer.empty());
+}
+
+TEST_CASE("simulator streams support independent full duplex and common PCM rates") {
+    for (uint32_t rate : { 16000u, 44100u, 48000u }) {
+        CAPTURE(rate);
+        const AudioStreamConfig config { rate, 16, 1 };
+        Stream input;
+        Stream output;
+        REQUIRE(audio_stream_open_input(&audio_stream_device, &config, &input.handle) == ERROR_NONE);
+        REQUIRE(audio_stream_open_output(&audio_stream_device, &config, &output.handle) == ERROR_NONE);
+        AudioStreamHandle duplicate = nullptr;
+        CHECK(audio_stream_open_output(&audio_stream_device, &config, &duplicate) == ERROR_INVALID_STATE);
+        std::vector<int16_t> samples(rate / 20, 1234);
+        size_t count = 0;
+        REQUIRE(audio_stream_write(output.handle, samples.data(), samples.size() * 2, &count, pdMS_TO_TICKS(1000)) == ERROR_NONE);
+        CHECK(count == samples.size() * 2);
+        REQUIRE(audio_stream_read(input.handle, samples.data(), samples.size() * 2, &count, pdMS_TO_TICKS(1000)) == ERROR_NONE);
+        CHECK(count == samples.size() * 2);
+        CHECK(std::all_of(samples.begin(), samples.end(), [](int16_t sample) { return sample == 0; }));
+        REQUIRE(audio_stream_close(output.handle) == ERROR_NONE);
+        output.handle = nullptr;
+        // Closing the speaker must not stop the microphone.
+        REQUIRE(audio_stream_read(input.handle, samples.data(), samples.size() * 2, &count, pdMS_TO_TICKS(1000)) == ERROR_NONE);
+    }
+}
+
+TEST_CASE("simulator audio controls persist across opens and disabling closes output") {
+    auto* device = &audio_stream_device;
+    REQUIRE(audio_stream_set_volume(device, AUDIO_CODEC_DIR_OUTPUT, 25.0f) == ERROR_NONE);
+    REQUIRE(audio_stream_set_mute(device, AUDIO_CODEC_DIR_OUTPUT, true) == ERROR_NONE);
+    const AudioStreamConfig config { 48000, 16, 2 };
+    Stream output;
+    REQUIRE(audio_stream_open_output(device, &config, &output.handle) == ERROR_NONE);
+    float volume = 0;
+    bool muted = false;
+    REQUIRE(audio_codec_get_volume(&speaker, AUDIO_CODEC_DIR_OUTPUT, &volume) == ERROR_NONE);
+    REQUIRE(audio_codec_get_mute(&speaker, AUDIO_CODEC_DIR_OUTPUT, &muted) == ERROR_NONE);
+    CHECK(volume == 25.0f);
+    CHECK(muted);
+    REQUIRE(audio_stream_set_enabled(device, AUDIO_CODEC_DIR_OUTPUT, false) == ERROR_NONE);
+    output.handle = nullptr; // set_enabled closes and owns destruction of the handle
+    CHECK(audio_stream_open_output(device, &config, &output.handle) == ERROR_NOT_ALLOWED);
+    REQUIRE(audio_stream_set_enabled(device, AUDIO_CODEC_DIR_OUTPUT, true) == ERROR_NONE);
+    REQUIRE(audio_stream_set_mute(device, AUDIO_CODEC_DIR_OUTPUT, false) == ERROR_NONE);
+    REQUIRE(audio_stream_open_output(device, &config, &output.handle) == ERROR_NONE);
+}
+
+TEST_CASE("bounded playback reports partial progress on a nonblocking timeout") {
+    const AudioStreamConfig config { 48000, 16, 2 };
+    Stream output;
+    REQUIRE(audio_stream_open_output(&audio_stream_device, &config, &output.handle) == ERROR_NONE);
+    std::vector<int16_t> samples(48000 * 2, 0);
+    size_t count = 999;
+    CHECK(audio_stream_write(output.handle, samples.data(), samples.size() * 2, &count, 0) == ERROR_TIMEOUT);
+    CHECK(count > 0);
+    CHECK(count < samples.size() * 2);
+    CHECK(count % 4 == 0);
+}
+
+TEST_CASE("converted streams report partial progress on timeout") {
+    const AudioStreamConfig config { 16000, 16, 1 };
+    Stream output;
+    Stream input;
+    REQUIRE(audio_stream_open_output(&audio_stream_device, &config, &output.handle) == ERROR_NONE);
+    REQUIRE(audio_stream_open_input(&audio_stream_device, &config, &input.handle) == ERROR_NONE);
+    std::vector<int16_t> samples(16000, 0);
+    size_t count = 999;
+    CHECK(audio_stream_write(output.handle, samples.data(), samples.size() * 2, &count, 0) == ERROR_TIMEOUT);
+    CHECK(count > 0);
+    CHECK(count < samples.size() * 2);
+    CHECK(count % 2 == 0);
+    vTaskDelay(pdMS_TO_TICKS(30)); // allow dummy capture to produce some samples
+    count = 999;
+    CHECK(audio_stream_read(input.handle, samples.data(), samples.size() * 2, &count, 0) == ERROR_TIMEOUT);
+    CHECK(count > 0);
+    CHECK(count < samples.size() * 2);
+    CHECK(count % 2 == 0);
+}
+
+TEST_CASE("missing selected microphone does not prevent speaker playback") {
+    REQUIRE(SDL_setenv("SIM_AUDIO_INPUT", "tactility-nonexistent-microphone", 1) == 0);
+    AudioCodecDirection capability;
+    CHECK(audio_codec_get_capabilities(&microphone, &capability) == ERROR_NOT_SUPPORTED);
+    const AudioCodecStreamConfig config { 48000, 16, 1, AUDIO_CODEC_DIR_INPUT };
+    CHECK(audio_codec_open(&microphone, &config) == ERROR_NOT_SUPPORTED);
+    CHECK(audio_codec_get_capabilities(&speaker, &capability) == ERROR_NONE);
+    CHECK(capability == AUDIO_CODEC_DIR_OUTPUT);
+    REQUIRE(SDL_setenv("SIM_AUDIO_INPUT", "", 1) == 0);
+}
+
+TEST_CASE("unsupported sample widths fail without breaking a later open") {
+    AudioStreamConfig config { 16000, 24, 1 };
+    Stream output;
+    CHECK(audio_stream_open_output(&audio_stream_device, &config, &output.handle) != ERROR_NONE);
+    CHECK(output.handle == nullptr);
+    config.bits_per_sample = 16;
+    REQUIRE(audio_stream_open_output(&audio_stream_device, &config, &output.handle) == ERROR_NONE);
+}
+
+TEST_CASE("zero sample rate is rejected before conversion") {
+    const AudioStreamConfig config { 0, 16, 1 };
+    Stream output;
+    CHECK(audio_stream_open_output(&audio_stream_device, &config, &output.handle) == ERROR_INVALID_ARGUMENT);
+}
+
+TEST_CASE("disabling while a codec is opening cancels the pending stream") {
+    const auto* original_api = static_cast<const AudioCodecApi*>(sdl_audio_driver.api);
+    static const AudioCodecApi* wrapped_api;
+    wrapped_api = original_api;
+    AudioCodecApi delayed_api = *original_api;
+    delayed_api.open = [](Device* device, const AudioCodecStreamConfig* config) {
+        vTaskDelay(pdMS_TO_TICKS(50)); // models waiting for microphone permission
+        return wrapped_api->open(device, config);
+    };
+    sdl_audio_driver.api = &delayed_api;
+    struct RestoreApi {
+        const AudioCodecApi* api;
+        ~RestoreApi() { sdl_audio_driver.api = api; }
+    } restore { original_api };
+    REQUIRE(xTaskCreate([](void*) {
+        vTaskDelay(pdMS_TO_TICKS(5));
+        audio_stream_set_enabled(&audio_stream_device, AUDIO_CODEC_DIR_OUTPUT, false);
+        // Re-enabling does not resurrect the cancelled attempt.
+        audio_stream_set_enabled(&audio_stream_device, AUDIO_CODEC_DIR_OUTPUT, true);
+        vTaskDelete(nullptr);
+    }, "disable-audio", 8192, nullptr, 1, nullptr) == pdPASS);
+    const AudioStreamConfig config { 48000, 16, 2 };
+    Stream output;
+    CHECK(audio_stream_open_output(&audio_stream_device, &config, &output.handle) == ERROR_NOT_ALLOWED);
+    CHECK(output.handle == nullptr);
+    sdl_audio_driver.api = original_api;
+    REQUIRE(audio_stream_open_output(&audio_stream_device, &config, &output.handle) == ERROR_NONE);
+}
+
+TEST_CASE("hardware output smoke test" * doctest::skip()) {
+    // Explicit opt-in only: SDL_AUDIODRIVER=coreaudio ... --no-skip --test-case='hardware output smoke test'
+    const AudioStreamConfig config { 48000, 16, 2 };
+    Stream output;
+    REQUIRE(audio_stream_set_volume(&audio_stream_device, AUDIO_CODEC_DIR_OUTPUT, 20) == ERROR_NONE);
+    REQUIRE(audio_stream_open_output(&audio_stream_device, &config, &output.handle) == ERROR_NONE);
+    std::vector<int16_t> samples(48000); // half a second, stereo, quiet 440 Hz tone
+    for (size_t frame = 0; frame < samples.size() / 2; ++frame) {
+        samples[frame * 2] = samples[frame * 2 + 1] = static_cast<int16_t>(3000 * std::sin(frame * 440.0 * 6.283185307 / 48000));
+    }
+    size_t count = 0;
+    REQUIRE(audio_stream_write(output.handle, samples.data(), samples.size() * 2, &count, pdMS_TO_TICKS(2000)) == ERROR_NONE);
+    CHECK(count == samples.size() * 2);
+}
+
+TEST_CASE("disk PCM capture and playback apply gain and mute" * doctest::skip()) {
+    REQUIRE(std::strcmp(SDL_GetCurrentAudioDriver(), "disk") == 0);
+    auto* device = &audio_stream_device;
+    const AudioStreamConfig config { 48000, 16, 1 };
+    Stream input;
+    Stream output;
+    REQUIRE(audio_stream_set_volume(device, AUDIO_CODEC_DIR_INPUT, 50) == ERROR_NONE);
+    REQUIRE(audio_stream_set_volume(device, AUDIO_CODEC_DIR_OUTPUT, 25) == ERROR_NONE);
+    REQUIRE(audio_stream_open_input(device, &config, &input.handle) == ERROR_NONE);
+    REQUIRE(audio_stream_open_output(device, &config, &output.handle) == ERROR_NONE);
+    std::vector<int16_t> samples(960, -1);
+    size_t count = 0;
+    REQUIRE(audio_stream_read(input.handle, samples.data(), samples.size() * 2, &count, pdMS_TO_TICKS(1000)) == ERROR_NONE);
+    CHECK(count == samples.size() * 2);
+    // Fixture contains 10000; microphone gain is 50%.
+    CHECK(std::all_of(samples.begin(), samples.end(), [](int16_t sample) { return sample == 5000; }));
+    REQUIRE(audio_stream_write(output.handle, samples.data(), samples.size() * 2, &count, pdMS_TO_TICKS(1000)) == ERROR_NONE);
+    REQUIRE(audio_stream_close(output.handle) == ERROR_NONE);
+    output.handle = nullptr;
+    {
+        std::ifstream file(std::getenv("SDL_DISKAUDIOFILE"), std::ios::binary);
+        REQUIRE(file.good());
+        size_t nonzero = 0;
+        int16_t sample;
+        while (file.read(reinterpret_cast<char*>(&sample), sizeof(sample))) {
+            CHECK((sample == 0 || sample == 1250)); // 25% output volume
+            if (sample != 0) nonzero++;
+        }
+        CHECK(nonzero == samples.size() * 2); // mono was duplicated to stereo
+    }
+    REQUIRE(audio_stream_set_mute(device, AUDIO_CODEC_DIR_INPUT, true) == ERROR_NONE);
+    REQUIRE(audio_stream_read(input.handle, samples.data(), samples.size() * 2, &count, pdMS_TO_TICKS(1000)) == ERROR_NONE);
+    CHECK(std::all_of(samples.begin(), samples.end(), [](int16_t sample) { return sample == 0; }));
+    REQUIRE(audio_stream_set_mute(device, AUDIO_CODEC_DIR_OUTPUT, true) == ERROR_NONE);
+    REQUIRE(audio_stream_open_output(device, &config, &output.handle) == ERROR_NONE);
+    std::fill(samples.begin(), samples.end(), 5000);
+    REQUIRE(audio_stream_write(output.handle, samples.data(), samples.size() * 2, &count, pdMS_TO_TICKS(1000)) == ERROR_NONE);
+    REQUIRE(audio_stream_close(output.handle) == ERROR_NONE);
+    output.handle = nullptr;
+    std::ifstream file(std::getenv("SDL_DISKAUDIOFILE"), std::ios::binary);
+    REQUIRE(file.good());
+    size_t total = 0;
+    int16_t sample;
+    while (file.read(reinterpret_cast<char*>(&sample), sizeof(sample))) {
+        CHECK(sample == 0);
+        total++;
+    }
+    CHECK(total >= samples.size() * 2);
+}
+
+struct TestContext { int argc; char** argv; int result = 1; };
+
+static void run_tests(void* argument) {
+    auto* data = static_cast<TestContext*>(argument);
+    Module* modules[] = { &platform_posix_module, &simulator_module, &audio_stream_module, nullptr };
+    DtsDevice devices[] = { DTS_DEVICE_TERMINATOR };
+    if (kernel_init(modules, devices) == ERROR_NONE
+        && device_construct_add_start(&speaker, "tactility,sdl-audio") == ERROR_NONE
+        && device_construct_add_start(&microphone, "tactility,sdl-audio") == ERROR_NONE) {
+        doctest::Context context(data->argc, data->argv);
+        context.setOption("no-breaks", true);
+        data->result = context.run();
+        device_stop(&microphone);
+        device_stop(&speaker);
+    }
+    vTaskEndScheduler();
+    vTaskDelete(nullptr);
+}
+
+int main(int argc, char** argv) {
+    if (std::getenv("SDL_AUDIODRIVER") == nullptr) SDL_setenv("SDL_AUDIODRIVER", "dummy", 1);
+    char input_path[] = "sim-audio-input-XXXXXX";
+    char output_path[] = "sim-audio-output-XXXXXX";
+    const bool disk = std::strcmp(std::getenv("SDL_AUDIODRIVER"), "disk") == 0;
+    if (disk) {
+        const int input_fd = mkstemp(input_path);
+        const int output_fd = mkstemp(output_path);
+        if (input_fd < 0 || output_fd < 0) return 1;
+        FILE* file = fdopen(input_fd, "wb");
+        if (file == nullptr) return 1;
+        const std::vector<int16_t> fixture(48000, 10000);
+        const size_t written = std::fwrite(fixture.data(), sizeof(int16_t), fixture.size(), file);
+        std::fclose(file);
+        ::close(output_fd);
+        if (written != fixture.size()) return 1;
+        SDL_setenv("SDL_DISKAUDIOFILEIN", input_path, 1);
+        SDL_setenv("SDL_DISKAUDIOFILE", output_path, 1);
+    }
+    TestContext data { argc, argv };
+    if (xTaskCreate(run_tests, "audio-test", 32768, &data, 1, nullptr) != pdPASS) return 1;
+    vTaskStartScheduler();
+    if (disk) {
+        std::remove(input_path);
+        std::remove(output_path);
+    }
+    return data.result;
+}

Documentation/simulator-audio.md

@@ -0,0 +1,93 @@
+# Simulator audio
+
+The desktop simulator exposes an SDL speaker and microphone through Tactility's
+standard `audio_stream_*` API. On macOS, SDL uses CoreAudio. Audio Settings controls
+the simulator's input/output volume, mute, and enabled state; these controls do not
+change macOS's system volume.
+
+## Running on macOS
+
+Build the simulator in the usual host build environment (with `python`, `lark`,
+and `pyyaml` available, and without `ESP_IDF_VERSION`):
+
+```sh
+cmake -S . -B buildsim
+cmake --build buildsim --target Tactility -j 8
+```
+
+Create a fresh application bundle (the script deliberately refuses to overwrite
+an existing bundle):
+
+```sh
+sh Buildscripts/release-simulator-macos-app.sh buildsim release/Tactility-audio.app
+open release/Tactility-audio.app
+```
+
+Alternatively, run `../buildsim/Tactility/Tactility` with `Data/` as the working
+directory. Both the executable and the application bundle include a microphone
+usage description. macOS asks for microphone access on the first actual recording
+request, not at simulator startup. If denied, enable access in **System Settings
+→ Privacy & Security → Microphone** and relaunch. For command-line launches, macOS
+may attribute the permission to the terminal or launching application.
+
+A Mac mini needs an external input device, such as a USB mic or headset. Without
+an input device, speaker output still works and input is reported unavailable.
+Connect the input before launch for predictable discovery/UI behavior.
+
+## Selecting devices
+
+By default, each stream opens the system's default device. Startup logs list SDL's
+device names. Optional environment variables select an exact name:
+
+```sh
+SIM_AUDIO_OUTPUT="Mac mini Speakers" SIM_AUDIO_INPUT="USB Microphone" \
+  release/Tactility-audio.app/Contents/MacOS/Tactility
+```
+
+- `SIM_AUDIO_OUTPUT`: exact output name, or `none` to disable output.
+- `SIM_AUDIO_INPUT`: exact input name, or `none` to disable input.
+- Unset or empty values use the system default.
+
+Selection is applied when opening a stream. An already-open stream does not
+automatically switch when the system default changes; close/reopen it or relaunch.
+A missing selected device causes an open failure rather than silently selecting a
+different device. Permission/device errors are logged under `SdlAudio`.
+
+## Formats and behavior
+
+- Signed 16-bit PCM; the shared stream module converts app sample rates and channel
+  counts to 48 kHz mono capture / stereo playback. SDL handles host format conversion.
+- One input and one output stream can be open simultaneously.
+- Read/write from a worker task, never the LVGL thread.
+- Audio callbacks use bounded lock-free buffers, with silence on playback underrun
+  and dropped incoming frames on capture overflow.
+- Reads/writes report partial byte counts on timeout, including converted streams.
+- Closing output drains its bounded buffer for up to 250 ms. Closing input does not
+  affect output, and vice versa.
+- No audio mixing or acoustic echo cancellation is added by this backend. Use
+  headphones when testing simultaneous microphone capture and playback.
+
+## Verification
+
+```sh
+cmake --build buildsim --target SimulatorAudioTests -j 8
+ctest --test-dir buildsim/Tests -R SimulatorAudio --output-on-failure
+```
+
+These tests use SDL's dummy and disk backends without requiring microphone access.
+They cover full duplex, 16/44.1/48 kHz app formats, bounded buffering, partial
+timeouts, enable/disable, unavailable inputs, and sample-level input/output gain
+and mute. They also cover disabling audio while a slow codec open is pending,
+as can happen during a microphone permission prompt. Disk fixtures and output
+files are temporary and removed after the run.
+
+To explicitly play a quiet half-second 440 Hz tone through real Mac audio:
+
+```sh
+SDL_AUDIODRIVER=coreaudio SIM_AUDIO_OUTPUT= \
+  buildsim/Tests/simulator/SimulatorAudioTests \
+  --no-skip --test-case="hardware output smoke test"
+```
+
+Physical microphone capture, the first-use permission prompt, and live device
+unplugging require a separate manual check with an input device attached.

Drivers/audio-stream-module/source/audio_stream.cpp

@@ -113,6 +113,10 @@ struct AudioStreamHandleImpl : AudioStreamHandleData {
     SemaphoreHandle_t drain_semaphore = nullptr;
 };
 
+// A slow codec open (notably the macOS microphone permission prompt) reserves a
+// direction before a real handle exists. It must never be passed to close_stream().
+AudioStreamHandleImpl* const OPENING_STREAM = reinterpret_cast<AudioStreamHandleImpl*>(1);
+
 struct AudioStreamData {
     Device* input_codec = nullptr;
     Device* output_codec = nullptr;
@@ -130,6 +134,8 @@ struct AudioStreamData {
     bool output_muted = false;
     AudioStreamHandleImpl* open_input = nullptr;
     AudioStreamHandleImpl* open_output = nullptr;
+    bool input_open_cancelled = false;
+    bool output_open_cancelled = false;
     // Guards open_input/open_output and the closing/busy_count fields of any handle reachable
     // through them, so close (possibly forced by set_enabled) can't race with read/write.
     SemaphoreHandle_t mutex = nullptr;
@@ -261,7 +267,7 @@ error_t open_stream(Device* device, const struct AudioStreamConfig* config, Audi
         return ERROR_INVALID_ARGUMENT;
     }
 
-    if (config->channels == 0) {
+    if (config->channels == 0 || config->sample_rate == 0) {
         return ERROR_INVALID_ARGUMENT;
     }
 
@@ -291,7 +297,9 @@ error_t open_stream(Device* device, const struct AudioStreamConfig* config, Audi
 
     // Reserve the slot with a placeholder so concurrent opens can't race past the check
     // above while we do the (potentially slow) codec open below outside the lock.
-    auto* reservation = reinterpret_cast<AudioStreamHandleImpl*>(1);
+    auto* reservation = OPENING_STREAM;
+    bool* open_cancelled = is_input ? &data->input_open_cancelled : &data->output_open_cancelled;
+    *open_cancelled = false;
     *slot = reservation;
     xSemaphoreGive(data->mutex);
 
@@ -361,6 +369,18 @@ error_t open_stream(Device* device, const struct AudioStreamConfig* config, Audi
     }
 
     xSemaphoreTake(data->mutex, portMAX_DELAY);
+    if (*open_cancelled) {
+        // Keep the reservation until the codec is closed, so re-enabling cannot
+        // open a second stream while this cancelled open is still cleaning up.
+        xSemaphoreGive(data->mutex);
+        vSemaphoreDelete(handle->drain_semaphore);
+        delete handle;
+        audio_codec_close(codec);
+        xSemaphoreTake(data->mutex, portMAX_DELAY);
+        *slot = nullptr;
+        xSemaphoreGive(data->mutex);
+        return ERROR_NOT_ALLOWED;
+    }
     *slot = handle;
     xSemaphoreGive(data->mutex);
 
@@ -377,6 +397,7 @@ error_t open_output(Device* device, const struct AudioStreamConfig* config, Audi
 }
 
 error_t read_stream(AudioStreamHandle handle_base, void* out_data, size_t data_size, size_t* bytes_read, TickType_t timeout) {
+    if (bytes_read != nullptr) *bytes_read = 0;
     auto* handle = static_cast<AudioStreamHandleImpl*>(handle_base);
     if (handle->direction != AUDIO_CODEC_DIR_INPUT || handle->bytes_per_frame == 0) {
         return ERROR_INVALID_STATE;
@@ -419,7 +440,7 @@ error_t read_stream(AudioStreamHandle handle_base, void* out_data, size_t data_s
 
         size_t codec_bytes_read = 0;
         result = audio_codec_read(data->input_codec, handle->codec_buffer.data(), codec_bytes_needed, &codec_bytes_read, timeout);
-        if (result == ERROR_NONE) {
+        if (codec_bytes_read > 0) {
             size_t codec_frames_read = codec_bytes_read / handle->codec_bytes_per_frame;
             const int16_t* rate_input = reinterpret_cast<const int16_t*>(handle->codec_buffer.data());
             uint8_t rate_input_channels = handle->codec_channels;
@@ -448,7 +469,7 @@ error_t read_stream(AudioStreamHandle handle_base, void* out_data, size_t data_s
         }
     }
 
-    if (result == ERROR_NONE && handle->input_gain != 1.0f && bytes_read != nullptr && *bytes_read > 0) {
+    if (handle->input_gain != 1.0f && bytes_read != nullptr && *bytes_read > 0) {
         auto* samples = reinterpret_cast<int16_t*>(out_data);
         size_t sample_count = *bytes_read / sizeof(int16_t);
         for (size_t i = 0; i < sample_count; i++) {
@@ -462,6 +483,7 @@ error_t read_stream(AudioStreamHandle handle_base, void* out_data, size_t data_s
 }
 
 error_t write_stream(AudioStreamHandle handle_base, const void* in_data, size_t data_size, size_t* bytes_written, TickType_t timeout) {
+    if (bytes_written != nullptr) *bytes_written = 0;
     auto* handle = static_cast<AudioStreamHandleImpl*>(handle_base);
     if (handle->direction != AUDIO_CODEC_DIR_OUTPUT || handle->bytes_per_frame == 0) {
         return ERROR_INVALID_STATE;
@@ -532,9 +554,13 @@ error_t write_stream(AudioStreamHandle handle_base, const void* in_data, size_t
         size_t codec_bytes_to_write = codec_frames * handle->codec_bytes_per_frame;
         size_t codec_bytes_written = 0;
         result = audio_codec_write(data->output_codec, handle->codec_buffer.data(), codec_bytes_to_write, &codec_bytes_written, timeout);
-        if (result == ERROR_NONE && bytes_written != nullptr) {
-            // The caller provided `data_size` worth of input; we consumed all of it (resampled/converted).
-            *bytes_written = data_size;
+        if (bytes_written != nullptr && codec_frames > 0) {
+            // A bounded host/hardware queue can accept only part of a converted write,
+            // including when returning ERROR_TIMEOUT. Report progress in app-side whole
+            // frames rather than leaving the count untouched or claiming the entire write.
+            size_t written_frames = codec_bytes_written / handle->codec_bytes_per_frame;
+            if (written_frames > codec_frames) written_frames = codec_frames;
+            *bytes_written = (in_frames * written_frames / codec_frames) * handle->bytes_per_frame;
         }
     }
 
@@ -686,13 +712,17 @@ error_t set_enabled(Device* device, AudioCodecDirection direction, bool enabled)
         data->output_enabled = enabled;
     }
 
-    // Capture and clear the slot under the lock so we hand close_stream() a pointer that
-    // can't simultaneously be torn down by a racing close from the owning app (close_stream
-    // re-checks `*slot == handle` and no-ops if it's already been cleared/replaced).
+    // A pending open has no handle to close yet. Let its owning task clean up when
+    // the codec returns, even if the user re-enables the direction in the meantime.
     AudioStreamHandleImpl* to_close = nullptr;
     if (!enabled) {
         AudioStreamHandleImpl** slot = is_input ? &data->open_input : &data->open_output;
-        to_close = *slot;
+        if (*slot == OPENING_STREAM) {
+            if (is_input) data->input_open_cancelled = true;
+            else data->output_open_cancelled = true;
+        } else {
+            to_close = *slot;
+        }
     }
     xSemaphoreGive(data->mutex);
 

Drivers/es8311-module/bindings/everest,es8311.yaml

@@ -9,3 +9,7 @@ properties:
     type: phandle
     required: true
     description: "I2S controller device that carries audio data"
+  input-gain-percent:
+    type: int
+    default: 100
+    description: "Extra digital gain multiplier applied by audio_stream on top of the ES8311's own 42dB hardware ADC gain, as an integer percentage (100 = 1.0x / no extra boost). For quiet MEMS mic capsules that are still quiet even at max hardware gain."

Drivers/es8311-module/include/drivers/es8311.h

@@ -25,6 +25,14 @@ struct Es8311Config {
     uint8_t address;
     /** I2S controller device that carries audio data */
     struct Device* i2s_device;
+    /**
+     * Extra fixed digital gain multiplier applied by audio_stream on top of the ES8311's
+     * own hardware ADC gain (0..42dB), as an integer percentage (100 = 1.0x / no extra boost).
+     * Small MEMS mic capsules can still sound quiet even near max hardware gain; this is for
+     * boards where 42dB hardware gain alone isn't enough. devicetree has no float property type,
+     * hence the x100 integer encoding.
+     */
+    uint16_t input_gain_percent;
 };
 
 #ifdef __cplusplus

Drivers/es8311-module/source/es8311.cpp

@@ -31,6 +31,7 @@ struct Es8311Data {
     bool is_open = false;
     AudioCodecDirection open_direction = AUDIO_CODEC_DIR_BOTH;
     esp_codec_dev_sample_info_t open_sample_info = {};
+    float input_gain = 1.0f;
 };
 
 #define GET_CONFIG(device) (static_cast<const Es8311Config*>((device)->config))
@@ -144,8 +145,8 @@ error_t set_volume(Device* device, AudioCodecDirection direction, float volume_p
     }
 
     if (direction == AUDIO_CODEC_DIR_INPUT) {
-        // ES8311 ADC gain range is roughly 0..24 dB; map 0..100% linearly onto it.
-        float db = (volume_percent / 100.0f) * 24.0f;
+        // ES8311 ADC gain supports 0..42dB (0,6,12,18,24,30,36,42) in 6dB steps
+        float db = (volume_percent / 100.0f) * 42.0f;
         return (esp_codec_dev_set_in_gain(data->codec_device, db) == ESP_CODEC_DEV_OK) ? ERROR_NONE : ERROR_RESOURCE;
     }
 
@@ -172,7 +173,8 @@ error_t get_volume(Device* device, AudioCodecDirection direction, float* volume_
         if (esp_codec_dev_get_in_gain(data->codec_device, &db) != ESP_CODEC_DEV_OK) {
             return ERROR_RESOURCE;
         }
-        *volume_percent = (db / 24.0f) * 100.0f;
+        *volume_percent = (db / 42.0f) * 100.0f;
+        if (*volume_percent > 100.0f) *volume_percent = 100.0f;
         return ERROR_NONE;
     }
 
@@ -235,6 +237,12 @@ error_t get_capabilities(Device* device, AudioCodecDirection* supported_directio
     return ERROR_NONE;
 }
 
+error_t get_input_gain_multiplier(Device* device, float* gain) {
+    auto* data = GET_DATA(device);
+    *gain = data->input_gain;
+    return ERROR_NONE;
+}
+
 static const struct AudioCodecApi API = {
     .open = open,
     .close = close,
@@ -247,7 +255,7 @@ static const struct AudioCodecApi API = {
     .get_native_sample_rate = get_native_sample_rate,
     .get_native_channels = get_native_channels,
     .get_capabilities = get_capabilities,
-    .get_input_gain_multiplier = nullptr,
+    .get_input_gain_multiplier = get_input_gain_multiplier,
 };
 
 // endregion
@@ -257,6 +265,11 @@ static const struct AudioCodecApi API = {
 error_t start_device(Device* device) {
     const auto* config = GET_CONFIG(device);
 
+    if (config->input_gain_percent > 2000) {
+        LOG_E(TAG, "Invalid input_gain_percent %u (must be 0..2000)", config->input_gain_percent);
+        return ERROR_RESOURCE;
+    }
+
     auto* i2c_controller = device_get_parent(device);
     if (i2c_controller == nullptr || device_get_type(i2c_controller) != &I2C_CONTROLLER_TYPE) {
         LOG_E(TAG, "Parent is not an I2C controller");
@@ -270,6 +283,8 @@ error_t start_device(Device* device) {
     }
 
     auto* data = new Es8311Data();
+    data->input_gain = (float) config->input_gain_percent / 100.0f;
+    if (config->input_gain_percent == 0) data->input_gain = 1.0f; // 0 means unset
 
     data->ctrl_if = audio_codec_adapter_new_i2c_ctrl(i2c_controller, config->address);
     data->data_if = audio_codec_adapter_new_i2s_data(i2s_controller);

Drivers/st77922-module/CMakeLists.txt

@@ -0,0 +1,11 @@
+cmake_minimum_required(VERSION 3.20)
+
+include("${CMAKE_CURRENT_LIST_DIR}/../../Buildscripts/module.cmake")
+
+file(GLOB_RECURSE SOURCE_FILES "source/*.c*")
+
+tactility_add_module(st77922-module
+    SRCS ${SOURCE_FILES}
+    INCLUDE_DIRS include/
+    REQUIRES TactilityKernel platform-esp32 esp_lcd_st77922 driver
+)

Drivers/st77922-module/bindings/sitronix,st77922-touch.yaml

@@ -0,0 +1,37 @@
+description: Touch interface integrated in the Sitronix ST77922 TDDI
+
+include: ["i2c-device.yaml"]
+
+compatible: "sitronix,st77922-touch"
+
+bus: i2c
+
+properties:
+  x-max:
+    type: int
+    required: true
+    description: Maximum X coordinate
+  y-max:
+    type: int
+    required: true
+    description: Maximum Y coordinate
+  swap-xy:
+    type: boolean
+    default: false
+    description: Swap the X and Y axes
+  mirror-x:
+    type: boolean
+    default: false
+    description: Mirror the X axis
+  mirror-y:
+    type: boolean
+    default: false
+    description: Mirror the Y axis
+  pin-reset:
+    type: phandles
+    default: GPIO_PIN_SPEC_NONE
+    description: Reset GPIO pin
+  pin-interrupt:
+    type: phandles
+    default: GPIO_PIN_SPEC_NONE
+    description: Interrupt GPIO pin

Drivers/st77922-module/bindings/sitronix,st77922.yaml

@@ -0,0 +1,47 @@
+description: Sitronix ST77922 QSPI display panel
+
+compatible: "sitronix,st77922"
+
+bus: spi
+
+properties:
+  horizontal-resolution:
+    type: int
+    required: true
+    description: Horizontal resolution in pixels
+  vertical-resolution:
+    type: int
+    required: true
+    description: Vertical resolution in pixels
+  mirror-x:
+    type: boolean
+    default: false
+    description: Mirror the X axis
+  mirror-y:
+    type: boolean
+    default: false
+    description: Mirror the Y axis
+  invert-color:
+    type: boolean
+    default: false
+    description: Invert the panel's color output
+  bgr-order:
+    type: boolean
+    default: false
+    description: Use BGR element order instead of RGB
+  bits-per-pixel:
+    type: int
+    default: 16
+    description: Color depth in bits per pixel
+  pixel-clock-hz:
+    type: int
+    default: 80000000
+    description: QSPI pixel clock frequency in Hz
+  transaction-queue-depth:
+    type: int
+    default: 10
+    description: Size of the internal SPI transaction queue
+  backlight:
+    type: phandle
+    default: "NULL"
+    description: Optional reference to this display's backlight device

Drivers/st77922-module/devicetree.yaml

@@ -0,0 +1,3 @@
+dependencies:
+  - TactilityKernel
+bindings: bindings

Drivers/st77922-module/include/bindings/st77922.h

@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/bindings/bindings.h>
+#include <drivers/st77922.h>
+
+DEFINE_DEVICETREE(st77922, struct St77922Config)

Drivers/st77922-module/include/bindings/st77922_touch.h

@@ -0,0 +1,7 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/bindings/bindings.h>
+#include <drivers/st77922_touch.h>
+
+DEFINE_DEVICETREE(st77922_touch, struct St77922TouchConfig)

Drivers/st77922-module/include/drivers/st77922.h

@@ -0,0 +1,20 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <tactility/device.h>
+
+struct St77922Config {
+    uint16_t horizontal_resolution;
+    uint16_t vertical_resolution;
+    bool mirror_x;
+    bool mirror_y;
+    bool invert_color;
+    bool bgr_order;
+    uint32_t bits_per_pixel;
+    uint32_t pixel_clock_hz;
+    uint8_t transaction_queue_depth;
+    struct Device* backlight;
+};

Drivers/st77922-module/include/drivers/st77922_touch.h

@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include <tactility/drivers/gpio.h>
+
+struct St77922TouchConfig {
+    uint8_t address;
+    uint16_t x_max;
+    uint16_t y_max;
+    bool swap_xy;
+    bool mirror_x;
+    bool mirror_y;
+    struct GpioPinSpec pin_reset;
+    struct GpioPinSpec pin_interrupt;
+};

Drivers/st77922-module/include/st77922_module.h

@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <tactility/module.h>
+
+extern Module st77922_module;

Drivers/st77922-module/source/module.cpp

@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <tactility/driver.h>
+#include <tactility/module.h>
+
+extern "C" {
+
+extern Driver st77922_driver;
+extern Driver st77922_touch_driver;
+
+static Driver* const st77922_drivers[] = {
+    &st77922_driver,
+    &st77922_touch_driver,
+    nullptr
+};
+
+Module st77922_module = {
+    .name = "st77922",
+    .drivers = st77922_drivers
+};
+
+} // extern "C"

Drivers/st77922-module/source/st77922.cpp

@@ -0,0 +1,270 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <drivers/st77922.h>
+#include <st77922_module.h>
+#include "st77922_init.h"
+
+#include <tactility/check.h>
+#include <tactility/device.h>
+#include <tactility/driver.h>
+#include <tactility/drivers/display.h>
+#include <tactility/drivers/esp32_spi.h>
+#include <tactility/drivers/spi_controller.h>
+#include <tactility/log.h>
+
+#include <esp_err.h>
+#include <esp_heap_caps.h>
+#include <esp_lcd_io_spi.h>
+#include <esp_lcd_panel_io.h>
+#include <esp_lcd_panel_ops.h>
+#include <esp_lcd_st77922.h>
+#include <freertos/semphr.h>
+#include <cstdlib>
+
+#define TAG "ST77922"
+#define GET_CONFIG(device) (static_cast<const St77922Config*>((device)->config))
+
+struct St77922Internal {
+    esp_lcd_panel_io_handle_t io_handle;
+    esp_lcd_panel_handle_t panel_handle;
+    SemaphoreHandle_t draw_done;
+    uint8_t* transfer_buffer;
+    size_t transfer_buffer_size;
+};
+
+static bool IRAM_ATTR transfer_done(esp_lcd_panel_io_handle_t, esp_lcd_panel_io_event_data_t*, void* context) {
+    auto* internal = static_cast<St77922Internal*>(context);
+    BaseType_t task_woken = pdFALSE;
+    xSemaphoreGiveFromISR(internal->draw_done, &task_woken);
+    return task_woken == pdTRUE;
+}
+
+static error_t start(Device* device) {
+    auto* parent = device_get_parent(device);
+    check(device_get_type(parent) == &SPI_CONTROLLER_TYPE);
+    const auto* spi = static_cast<const Esp32SpiConfig*>(parent->config);
+    const auto* config = GET_CONFIG(device);
+
+    GpioPinSpec cs;
+    if (esp32_spi_get_cs_pin(device, &cs) != ERROR_NONE) {
+        return ERROR_RESOURCE;
+    }
+
+    auto* internal = static_cast<St77922Internal*>(calloc(1, sizeof(St77922Internal)));
+    if (internal == nullptr) {
+        return ERROR_OUT_OF_MEMORY;
+    }
+    internal->draw_done = xSemaphoreCreateBinary();
+    if (internal->draw_done == nullptr) {
+        free(internal);
+        return ERROR_OUT_OF_MEMORY;
+    }
+    // The vendor port renders a complete frame in PSRAM, then copies it through a
+    // 1/10-frame DMA buffer. Besides making full-frame refresh possible, this keeps
+    // the panel's GRAM synchronized when animated objects invalidate old and new
+    // positions in separate LVGL regions.
+    const size_t bytes_per_pixel = config->bits_per_pixel / 8;
+    const size_t rows_per_transfer = config->vertical_resolution > 10
+        ? config->vertical_resolution / 10 : config->vertical_resolution;
+    internal->transfer_buffer_size =
+        static_cast<size_t>(config->horizontal_resolution) * rows_per_transfer * bytes_per_pixel;
+    if (spi->max_transfer_size > 0
+        && internal->transfer_buffer_size > static_cast<size_t>(spi->max_transfer_size)) {
+        internal->transfer_buffer_size = static_cast<size_t>(spi->max_transfer_size);
+    }
+    internal->transfer_buffer = static_cast<uint8_t*>(heap_caps_malloc(
+        internal->transfer_buffer_size, MALLOC_CAP_DMA | MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT));
+    if (internal->transfer_buffer == nullptr) {
+        vSemaphoreDelete(internal->draw_done);
+        free(internal);
+        return ERROR_OUT_OF_MEMORY;
+    }
+
+    esp_lcd_panel_io_spi_config_t io_config = {
+        .cs_gpio_num = static_cast<int>(cs.pin),
+        .dc_gpio_num = -1,
+        .spi_mode = 0,
+        .pclk_hz = config->pixel_clock_hz,
+        .trans_queue_depth = config->transaction_queue_depth,
+        .on_color_trans_done = transfer_done,
+        .user_ctx = internal,
+        .lcd_cmd_bits = 32,
+        .lcd_param_bits = 8,
+        .cs_ena_pretrans = 0,
+        .cs_ena_posttrans = 0,
+        .flags = {
+            .dc_high_on_cmd = 0,
+            .dc_low_on_data = 0,
+            .dc_low_on_param = 0,
+            .octal_mode = 0,
+            .quad_mode = 1,
+            .sio_mode = 0,
+            .lsb_first = 0,
+            .cs_high_active = 0,
+        },
+    };
+
+    esp_err_t result = esp_lcd_new_panel_io_spi(
+        static_cast<esp_lcd_spi_bus_handle_t>(spi->host), &io_config, &internal->io_handle);
+    if (result != ESP_OK) {
+        LOG_E(TAG, "Failed to create panel IO: %s", esp_err_to_name(result));
+        heap_caps_free(internal->transfer_buffer);
+        vSemaphoreDelete(internal->draw_done);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+
+    size_t init_count = 0;
+    st77922_vendor_config_t vendor = {
+        .init_cmds = st77922_board_init_commands(&init_count),
+        .init_cmds_size = static_cast<uint16_t>(init_count),
+        .flags = { .use_qspi_interface = 1 },
+    };
+    esp_lcd_panel_dev_config_t panel_config = {
+        .reset_gpio_num = -1,
+        .rgb_ele_order = config->bgr_order ? LCD_RGB_ELEMENT_ORDER_BGR : LCD_RGB_ELEMENT_ORDER_RGB,
+        .data_endian = LCD_RGB_DATA_ENDIAN_LITTLE,
+        .bits_per_pixel = config->bits_per_pixel,
+        .flags = { .reset_active_high = false },
+        .vendor_config = &vendor,
+    };
+    result = esp_lcd_new_panel_st77922(internal->io_handle, &panel_config, &internal->panel_handle);
+    bool ok = result == ESP_OK;
+    ok = ok && esp_lcd_panel_reset(internal->panel_handle) == ESP_OK;
+    ok = ok && esp_lcd_panel_init(internal->panel_handle) == ESP_OK;
+    ok = ok && ((!config->mirror_x && !config->mirror_y)
+        || esp_lcd_panel_mirror(internal->panel_handle, config->mirror_x, config->mirror_y) == ESP_OK);
+    ok = ok && (!config->invert_color || esp_lcd_panel_invert_color(internal->panel_handle, true) == ESP_OK);
+    ok = ok && esp_lcd_panel_disp_on_off(internal->panel_handle, true) == ESP_OK;
+    if (!ok) {
+        LOG_E(TAG, "Failed to bring up panel: %s", esp_err_to_name(result));
+        if (internal->panel_handle != nullptr) esp_lcd_panel_del(internal->panel_handle);
+        esp_lcd_panel_io_del(internal->io_handle);
+        heap_caps_free(internal->transfer_buffer);
+        vSemaphoreDelete(internal->draw_done);
+        free(internal);
+        return ERROR_RESOURCE;
+    }
+    device_set_driver_data(device, internal);
+    return ERROR_NONE;
+}
+
+static error_t stop(Device* device) {
+    auto* internal = static_cast<St77922Internal*>(device_get_driver_data(device));
+    if (esp_lcd_panel_del(internal->panel_handle) != ESP_OK
+        || esp_lcd_panel_io_del(internal->io_handle) != ESP_OK) {
+        return ERROR_RESOURCE;
+    }
+    heap_caps_free(internal->transfer_buffer);
+    vSemaphoreDelete(internal->draw_done);
+    free(internal);
+    device_set_driver_data(device, nullptr);
+    return ERROR_NONE;
+}
+
+static error_t reset(Device* device) {
+    auto* data = static_cast<St77922Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_reset(data->panel_handle) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+static error_t init(Device* device) {
+    auto* data = static_cast<St77922Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_init(data->panel_handle) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+static error_t draw_bitmap(Device* device, int32_t xs, int32_t ys, int32_t xe, int32_t ye, const void* pixels) {
+    auto* data = static_cast<St77922Internal*>(device_get_driver_data(device));
+    const auto* config = GET_CONFIG(device);
+    const size_t row_bytes = static_cast<size_t>(xe - xs) * config->bits_per_pixel / 8;
+    if (row_bytes == 0 || row_bytes > data->transfer_buffer_size) {
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    const size_t rows_per_transfer = data->transfer_buffer_size / row_bytes;
+    const auto* source = static_cast<const uint8_t*>(pixels);
+    int32_t chunk_y = ys;
+    while (chunk_y < ye) {
+        const size_t remaining_rows = static_cast<size_t>(ye - chunk_y);
+        const size_t chunk_rows = remaining_rows < rows_per_transfer ? remaining_rows : rows_per_transfer;
+        const size_t chunk_bytes = chunk_rows * row_bytes;
+        memcpy(data->transfer_buffer, source, chunk_bytes);
+
+        xSemaphoreTake(data->draw_done, 0);
+        if (esp_lcd_panel_draw_bitmap(
+                data->panel_handle, xs, chunk_y, xe, chunk_y + static_cast<int32_t>(chunk_rows),
+                data->transfer_buffer) != ESP_OK) {
+            LOG_E(TAG, "Failed to queue color transfer at y=%ld", static_cast<long>(chunk_y));
+            return ERROR_RESOURCE;
+        }
+        if (xSemaphoreTake(data->draw_done, pdMS_TO_TICKS(1000)) != pdTRUE) {
+            LOG_E(TAG, "Timed out waiting for color transfer at y=%ld", static_cast<long>(chunk_y));
+            return ERROR_TIMEOUT;
+        }
+
+        source += chunk_bytes;
+        chunk_y += static_cast<int32_t>(chunk_rows);
+    }
+    return ERROR_NONE;
+}
+static error_t mirror(Device* device, bool x, bool y) {
+    auto* data = static_cast<St77922Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_mirror(data->panel_handle, x, y) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+static bool get_mirror_x(Device* device) { return GET_CONFIG(device)->mirror_x; }
+static bool get_mirror_y(Device* device) { return GET_CONFIG(device)->mirror_y; }
+static error_t invert(Device* device, bool value) {
+    auto* data = static_cast<St77922Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_invert_color(data->panel_handle, value) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+static error_t on_off(Device* device, bool value) {
+    auto* data = static_cast<St77922Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_disp_on_off(data->panel_handle, value) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+static error_t sleep(Device* device, bool value) {
+    auto* data = static_cast<St77922Internal*>(device_get_driver_data(device));
+    return esp_lcd_panel_disp_sleep(data->panel_handle, value) == ESP_OK ? ERROR_NONE : ERROR_RESOURCE;
+}
+static DisplayColorFormat color_format(Device*) { return DISPLAY_COLOR_FORMAT_RGB565_SWAPPED; }
+static uint16_t resolution_x(Device* device) { return GET_CONFIG(device)->horizontal_resolution; }
+static uint16_t resolution_y(Device* device) { return GET_CONFIG(device)->vertical_resolution; }
+static void frame_buffer(Device*, uint8_t, void** output) { *output = nullptr; }
+static uint8_t frame_buffer_count(Device*) { return 0; }
+static error_t backlight(Device* device, Device** output) {
+    *output = GET_CONFIG(device)->backlight;
+    return *output == nullptr ? ERROR_NOT_SUPPORTED : ERROR_NONE;
+}
+
+static const DisplayApi display_api = {
+    .capabilities = DISPLAY_CAPABILITY_CAP_MIRROR | DISPLAY_CAPABILITY_INVERT_COLOR |
+        DISPLAY_CAPABILITY_ON_OFF | DISPLAY_CAPABILITY_SLEEP | DISPLAY_CAPABILITY_BACKLIGHT |
+        DISPLAY_CAPABILITY_REQUIRES_FULL_FRAME,
+    .reset = reset,
+    .init = init,
+    .draw_bitmap = draw_bitmap,
+    .mirror = mirror,
+    .swap_xy = nullptr,
+    .get_swap_xy = nullptr,
+    .get_mirror_x = get_mirror_x,
+    .get_mirror_y = get_mirror_y,
+    .set_gap = nullptr,
+    .get_gap_x = nullptr,
+    .get_gap_y = nullptr,
+    .invert_color = invert,
+    .disp_on_off = on_off,
+    .disp_sleep = sleep,
+    .get_color_format = color_format,
+    .get_resolution_x = resolution_x,
+    .get_resolution_y = resolution_y,
+    .get_frame_buffer = frame_buffer,
+    .get_frame_buffer_count = frame_buffer_count,
+    .get_backlight = backlight,
+    .has_capability = nullptr,
+};
+
+Driver st77922_driver = {
+    .name = "st77922",
+    .compatible = (const char*[]) { "sitronix,st77922", nullptr },
+    .start_device = start,
+    .stop_device = stop,
+    .api = &display_api,
+    .device_type = &DISPLAY_TYPE,
+    .owner = &st77922_module,
+    .internal = nullptr
+};

Drivers/st77922-module/source/st77922_init.c

@@ -0,0 +1,74 @@
+// SPDX-License-Identifier: Apache-2.0
+#include "st77922_init.h"
+
+// Initialization sequence supplied with the LCDWIKI/Hosyond ES3C35P vendor ESP-IDF demo.
+static const st77922_lcd_init_cmd_t init_commands[] = {
+    {0xF1, (uint8_t []){0x00}, 1, 0},
+    {0x60, (uint8_t []){0x00, 0x00, 0x00}, 3, 0},
+    {0x65, (uint8_t []){0x80}, 1, 0},
+    {0x79, (uint8_t []){0x06}, 1, 0},
+    {0x7B, (uint8_t []){0x00, 0x08, 0x08}, 3, 0},
+    {0x80, (uint8_t []){0x55, 0x62, 0x2F, 0x17, 0xF0, 0x52, 0x70, 0xD2, 0x52, 0x62, 0xEA}, 11, 0},
+    {0x81, (uint8_t []){0x26, 0x52, 0x72, 0x27}, 4, 0},
+    {0x84, (uint8_t []){0x92, 0x25}, 2, 0},
+    {0x87, (uint8_t []){0x10, 0x10, 0x58, 0x00, 0x02, 0x3A}, 6, 0},
+    {0x88, (uint8_t []){0x00, 0x00, 0x2C, 0x10, 0x04, 0x00, 0x00, 0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x06}, 15, 0},
+    {0x89, (uint8_t []){0x00, 0x00, 0x00}, 3, 0},
+    {0x8A, (uint8_t []){0x13, 0x00, 0x2C, 0x00, 0x00, 0x2C, 0x10, 0x10, 0x00, 0x3E, 0x19}, 11, 0},
+    {0x8B, (uint8_t []){0x15, 0xB1, 0xB1, 0x44, 0x96, 0x2C, 0x10, 0x97, 0x8E}, 9, 0},
+    {0x8C, (uint8_t []){0x1D, 0xB1, 0xB1, 0x44, 0x96, 0x2C, 0x10, 0x50, 0x0F, 0x01, 0xC5, 0x12, 0x09}, 13, 0},
+    {0x8D, (uint8_t []){0x0C}, 1, 0},
+    {0x8E, (uint8_t []){0x33, 0x01, 0x0C, 0x13, 0x01, 0x01}, 6, 0},
+    {0xB3, (uint8_t []){0x00, 0x30}, 2, 0},
+    {0xF1, (uint8_t []){0x00}, 1, 0},
+    {0x71, (uint8_t []){0xD0}, 1, 0},
+    {0x66, (uint8_t []){0x02, 0x3F}, 2, 0},
+    {0xBE, (uint8_t []){0x26, 0x00, 0x9D}, 3, 0},
+    {0x70, (uint8_t []){0x01, 0xA0, 0x11, 0x40, 0xE0, 0x00, 0x11, 0x69, 0x11, 0x00, 0x00, 0x1A}, 12, 0},
+    {0x90, (uint8_t []){0x04, 0x04, 0x55, 0x74, 0x00, 0x40, 0x43, 0x27, 0x27}, 9, 0},
+    {0x91, (uint8_t []){0x04, 0x04, 0x55, 0x75, 0x00, 0x40, 0x42, 0x27, 0x27}, 9, 0},
+    {0x92, (uint8_t []){0x04, 0x44, 0x55, 0xC0, 0x06, 0x00, 0x07, 0x05, 0x90, 0x27}, 10, 0},
+    {0x93, (uint8_t []){0x04, 0x43, 0x11, 0x00, 0x00, 0x00, 0x00, 0x05, 0x90, 0x27}, 10, 0},
+    {0x94, (uint8_t []){0x00, 0x00, 0x00, 0x00, 0x00, 0x00}, 6, 0},
+    {0x95, (uint8_t []){0x96, 0x16, 0x00, 0x00, 0xFF}, 5, 0},
+    {0x96, (uint8_t []){0x44, 0x53, 0x03, 0x12, 0x23, 0x24, 0x06, 0x05, 0x94, 0x27, 0x00, 0x44}, 12, 0},
+    {0x97, (uint8_t []){0x44, 0x53, 0x47, 0x56, 0x20, 0x20, 0x02, 0x01, 0x94, 0x27, 0x00, 0x44}, 12, 0},
+    {0xBA, (uint8_t []){0x55, 0x94, 0x2D, 0x94, 0x27}, 5, 0},
+    {0x9A, (uint8_t []){0x40, 0x00, 0x06, 0x00, 0x00, 0x00, 0x00}, 7, 0},
+    {0x9B, (uint8_t []){0x00, 0x00, 0x06, 0x00, 0x00, 0x00, 0x00}, 7, 0},
+    {0x9C, (uint8_t []){0x5C, 0x12, 0x00, 0x00, 0x10, 0x12, 0x00, 0x00, 0x10, 0x02, 0x00, 0x00, 0x00}, 13, 0},
+    {0x9D, (uint8_t []){0x8A, 0x51, 0x00, 0x00, 0x00, 0x80, 0x1E, 0x01}, 8, 0},
+    {0x9E, (uint8_t []){0x51, 0x00, 0x00, 0x00, 0x80, 0x1E, 0x01}, 7, 0},
+    {0xB4, (uint8_t []){0x1D, 0x1C, 0x1E, 0x0B, 0x14, 0x02, 0x13, 0x09, 0x1E, 0x00, 0x1E, 0x10}, 12, 0},
+    {0xB5, (uint8_t []){0x1D, 0x1C, 0x1E, 0x0A, 0x15, 0x03, 0x11, 0x08, 0x1E, 0x01, 0x1E, 0x12}, 12, 0},
+    {0xB6, (uint8_t []){0x77, 0x77, 0x00, 0x0A, 0xFF, 0x0A, 0xFF}, 7, 0},
+    {0x86, (uint8_t []){0xCD, 0x04, 0xB1, 0x02, 0x58, 0x12, 0x58, 0x0C, 0x13, 0x01, 0xA5, 0x00, 0xA5, 0xA5}, 14, 0},
+    {0xB7, (uint8_t []){0x07, 0x0A, 0x0E, 0x06, 0x05, 0x03, 0x2B, 0x03, 0x03, 0x42, 0x07, 0x10, 0x10, 0x2E, 0x3F, 0x0D}, 16, 0},
+    {0xB8, (uint8_t []){0x07, 0x0A, 0x0D, 0x05, 0x05, 0x02, 0x2B, 0x02, 0x03, 0x42, 0x06, 0x10, 0x0F, 0x2E, 0x3F, 0x0D}, 16, 0},
+    {0xB9, (uint8_t []){0x23, 0x23}, 2, 0},
+    {0xBF, (uint8_t []){0x10, 0x14, 0x14, 0x0B, 0x0B, 0x0B}, 6, 0},
+    {0xF2, (uint8_t []){0x00}, 1, 0},
+    {0x73, (uint8_t []){0x04, 0xDA, 0x12, 0x54, 0x47}, 5, 0},
+    {0x77, (uint8_t []){0x6B, 0x5B, 0xFD, 0xC3, 0xC5}, 5, 0},
+    {0x7A, (uint8_t []){0x15, 0x27}, 2, 0},
+    {0x7B, (uint8_t []){0x04, 0x57}, 2, 0},
+    {0x7E, (uint8_t []){0x01, 0x0E}, 2, 0},
+    {0xBF, (uint8_t []){0x36}, 1, 0},
+    {0xE3, (uint8_t []){0x40, 0x40}, 2, 0},
+    {0xF0, (uint8_t []){0x00}, 1, 0},
+    {0xD0, (uint8_t []){0x00}, 1, 0},
+    {0x2A, (uint8_t []){0x00, 0x00, 0x01, 0x3F}, 4, 0},
+    {0x2B, (uint8_t []){0x00, 0x00, 0x01, 0xDF}, 4, 0},
+    {0x21, NULL, 0, 0},
+    {0x11, NULL, 0, 120},
+    {0x29, NULL, 0, 0},
+    {0x2C, NULL, 0, 0},
+    {0x3A, (uint8_t []){0x01}, 1, 0},
+    {0x36, (uint8_t []){0x00}, 1, 0},
+    {0x35, (uint8_t []){0x01}, 1, 20},
+};
+
+const st77922_lcd_init_cmd_t* st77922_board_init_commands(size_t* count) {
+    *count = sizeof(init_commands) / sizeof(init_commands[0]);
+    return init_commands;
+}

Drivers/st77922-module/source/st77922_init.h

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: Apache-2.0
+#pragma once
+
+#include <stddef.h>
+#include <esp_lcd_st77922.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+const st77922_lcd_init_cmd_t* st77922_board_init_commands(size_t* count);
+
+#ifdef __cplusplus
+}
+#endif

Drivers/st77922-module/source/st77922_touch.cpp

@@ -0,0 +1,207 @@
+// SPDX-License-Identifier: Apache-2.0
+#include <drivers/st77922_touch.h>
+#include <st77922_module.h>
+
+#include <tactility/check.h>
+#include <tactility/device.h>
+#include <tactility/driver.h>
+#include <tactility/drivers/gpio_controller.h>
+#include <tactility/drivers/i2c_controller.h>
+#include <tactility/drivers/pointer.h>
+#include <tactility/log.h>
+
+#include <freertos/task.h>
+#include <algorithm>
+#include <cstdlib>
+
+#define TAG "ST77922 touch"
+#define GET_CONFIG(device) (static_cast<const St77922TouchConfig*>((device)->config))
+
+static constexpr uint16_t REG_MAX_TOUCHES = 0x0009;
+static constexpr uint16_t REG_TOUCH_INFO = 0x0010;
+static constexpr uint16_t REG_TOUCH_POINT0 = 0x0014;
+static constexpr uint8_t MAX_POINTS = 10;
+static constexpr TickType_t TIMEOUT = pdMS_TO_TICKS(1000);
+
+struct TouchPoint {
+    uint16_t x;
+    uint16_t y;
+};
+
+struct St77922TouchInternal {
+    Device* i2c;
+    GpioDescriptor* reset;
+    uint8_t supported_points;
+    uint8_t point_count;
+    TouchPoint points[MAX_POINTS];
+    bool swap_xy;
+    bool mirror_x;
+    bool mirror_y;
+};
+
+static error_t read_register(Device* i2c, uint16_t reg, uint8_t* data, size_t size, TickType_t timeout) {
+    const uint8_t address[] = {
+        static_cast<uint8_t>(reg >> 8),
+        static_cast<uint8_t>(reg & 0xFF),
+    };
+    return i2c_controller_write_read(i2c, 0x55, address, sizeof(address), data, size, timeout);
+}
+
+static error_t start(Device* device) {
+    auto* parent = device_get_parent(device);
+    check(device_get_type(parent) == &I2C_CONTROLLER_TYPE);
+    const auto* config = GET_CONFIG(device);
+
+    auto* internal = static_cast<St77922TouchInternal*>(calloc(1, sizeof(St77922TouchInternal)));
+    if (internal == nullptr) {
+        return ERROR_OUT_OF_MEMORY;
+    }
+    internal->i2c = parent;
+    internal->supported_points = 1;
+    internal->swap_xy = config->swap_xy;
+    internal->mirror_x = config->mirror_x;
+    internal->mirror_y = config->mirror_y;
+
+    if (config->pin_reset.gpio_controller != nullptr) {
+        internal->reset = gpio_descriptor_acquire(config->pin_reset.gpio_controller,
+            config->pin_reset.pin, GPIO_FLAG_DIRECTION_OUTPUT | GPIO_FLAG_ACTIVE_LOW, GPIO_OWNER_GPIO);
+        if (internal->reset == nullptr) {
+            free(internal);
+            return ERROR_RESOURCE;
+        }
+        if (gpio_descriptor_set_level(internal->reset, true) != ERROR_NONE) {
+            gpio_descriptor_release(internal->reset);
+            free(internal);
+            return ERROR_RESOURCE;
+        }
+        vTaskDelay(pdMS_TO_TICKS(10));
+        gpio_descriptor_set_level(internal->reset, false);
+        vTaskDelay(pdMS_TO_TICKS(100));
+    }
+
+    uint8_t supported = 0;
+    if (read_register(parent, REG_MAX_TOUCHES, &supported, 1, TIMEOUT) == ERROR_NONE
+        && supported > 0 && supported <= MAX_POINTS) {
+        internal->supported_points = supported;
+    }
+    LOG_I(TAG, "Controller reports %u touch points", internal->supported_points);
+    device_set_driver_data(device, internal);
+    return ERROR_NONE;
+}
+
+static error_t stop(Device* device) {
+    auto* internal = static_cast<St77922TouchInternal*>(device_get_driver_data(device));
+    if (internal->reset != nullptr) {
+        gpio_descriptor_release(internal->reset);
+    }
+    free(internal);
+    device_set_driver_data(device, nullptr);
+    return ERROR_NONE;
+}
+
+static error_t enter_sleep(Device*) { return ERROR_NOT_SUPPORTED; }
+static error_t exit_sleep(Device*) { return ERROR_NOT_SUPPORTED; }
+
+static error_t read_data(Device* device, TickType_t timeout) {
+    auto* internal = static_cast<St77922TouchInternal*>(device_get_driver_data(device));
+    uint8_t touch_info = 0;
+    if (read_register(internal->i2c, REG_TOUCH_INFO, &touch_info, 1, timeout) != ERROR_NONE) {
+        internal->point_count = 0;
+        return ERROR_RESOURCE;
+    }
+    if ((touch_info & 0x08) == 0) {
+        internal->point_count = 0;
+        return ERROR_NONE;
+    }
+
+    uint8_t data[7 * MAX_POINTS] = {};
+    const size_t read_size = 7 * internal->supported_points;
+    if (read_register(internal->i2c, REG_TOUCH_POINT0, data, read_size, timeout) != ERROR_NONE) {
+        internal->point_count = 0;
+        return ERROR_RESOURCE;
+    }
+
+    internal->point_count = 0;
+    for (uint8_t index = 0; index < internal->supported_points; index++) {
+        const uint8_t offset = index * 7;
+        if ((data[offset] & 0x80) == 0) {
+            continue;
+        }
+        internal->points[internal->point_count++] = {
+            .x = static_cast<uint16_t>(((data[offset] & 0x3F) << 8) | data[offset + 1]),
+            .y = static_cast<uint16_t>(((data[offset + 2] & 0x3F) << 8) | data[offset + 3]),
+        };
+    }
+    return ERROR_NONE;
+}
+
+static bool get_touched_points(Device* device, uint16_t* x, uint16_t* y, uint16_t* strength,
+    uint8_t* count, uint8_t maximum) {
+    auto* internal = static_cast<St77922TouchInternal*>(device_get_driver_data(device));
+    const auto* config = GET_CONFIG(device);
+    *count = std::min(internal->point_count, maximum);
+    for (uint8_t index = 0; index < *count; index++) {
+        uint16_t point_x = internal->points[index].x;
+        uint16_t point_y = internal->points[index].y;
+        if (internal->swap_xy) {
+            std::swap(point_x, point_y);
+        }
+        const uint16_t max_x = internal->swap_xy ? config->y_max : config->x_max;
+        const uint16_t max_y = internal->swap_xy ? config->x_max : config->y_max;
+        x[index] = internal->mirror_x ? max_x - point_x : point_x;
+        y[index] = internal->mirror_y ? max_y - point_y : point_y;
+        if (strength != nullptr) {
+            strength[index] = 0;
+        }
+    }
+    return *count > 0;
+}
+
+static error_t set_swap_xy(Device* device, bool value) {
+    static_cast<St77922TouchInternal*>(device_get_driver_data(device))->swap_xy = value;
+    return ERROR_NONE;
+}
+static error_t get_swap_xy(Device* device, bool* value) {
+    *value = static_cast<St77922TouchInternal*>(device_get_driver_data(device))->swap_xy;
+    return ERROR_NONE;
+}
+static error_t set_mirror_x(Device* device, bool value) {
+    static_cast<St77922TouchInternal*>(device_get_driver_data(device))->mirror_x = value;
+    return ERROR_NONE;
+}
+static error_t get_mirror_x(Device* device, bool* value) {
+    *value = static_cast<St77922TouchInternal*>(device_get_driver_data(device))->mirror_x;
+    return ERROR_NONE;
+}
+static error_t set_mirror_y(Device* device, bool value) {
+    static_cast<St77922TouchInternal*>(device_get_driver_data(device))->mirror_y = value;
+    return ERROR_NONE;
+}
+static error_t get_mirror_y(Device* device, bool* value) {
+    *value = static_cast<St77922TouchInternal*>(device_get_driver_data(device))->mirror_y;
+    return ERROR_NONE;
+}
+
+static const PointerApi pointer_api = {
+    .enter_sleep = enter_sleep,
+    .exit_sleep = exit_sleep,
+    .read_data = read_data,
+    .get_touched_points = get_touched_points,
+    .set_swap_xy = set_swap_xy,
+    .get_swap_xy = get_swap_xy,
+    .set_mirror_x = set_mirror_x,
+    .get_mirror_x = get_mirror_x,
+    .set_mirror_y = set_mirror_y,
+    .get_mirror_y = get_mirror_y,
+};
+
+Driver st77922_touch_driver = {
+    .name = "st77922-touch",
+    .compatible = (const char*[]) { "sitronix,st77922-touch", nullptr },
+    .start_device = start,
+    .stop_device = stop,
+    .api = &pointer_api,
+    .device_type = &POINTER_TYPE,
+    .owner = &st77922_module,
+    .internal = nullptr
+};

Modules/app-module/CMakeLists.txt

@@ -10,15 +10,29 @@ tactility_add_module(app-module
     INCLUDE_DIRS include/
     REQUIRES TactilityKernel service-module minitar
     PRIV_REQUIRES TactilityKernelCpp
+    WHOLE_ARCHIVE
 )
 
-# Tells source/io.cpp its real-syscall fallback must go through __real_read/write/close()
-# rather than calling ::read/::write/::close() directly, on every platform whose build wraps
-# those symbols (ESP-IDF always; POSIX except macOS, whose linker doesn't support --wrap) -
-# see Tactility/CMakeLists.txt and the top-level CMakeLists.txt for where that's applied.
-if (NOT APPLE)
+# Tells source/io.cpp its real-syscall fallback must go through __real_read/write/close() rather
+# than calling ::read/::write/::close() directly, on every platform where those are wrapped: via
+# -Wl,--wrap= on ESP-IDF (see the top-level CMakeLists.txt) and non-Apple POSIX (below), or via
+# source/stdio_wrap.cpp's dyld interpose on Apple (whose linker lacks --wrap).
+tactility_get_module_name(app-module MODULE_NAME)
+target_compile_definitions(${MODULE_NAME} PRIVATE TT_APP_IO_WRAPS_STDIO)
+
+# Routes every read()/write()/close() and printf-family call to source/stdio_wrap.cpp's __wrap_*
+# functions; see that file for what they do and why. ESP-IDF wraps the same symbols itself (see
+# the top-level CMakeLists.txt); Apple gets the same routing via dyld interpose instead, self-
+# registered in that file. PUBLIC so every consumer of this module (Tactility, and any test target
+# that links app-module directly) gets the flags too.
+if (NOT ESP_PLATFORM AND NOT APPLE)
     tactility_get_module_name(app-module MODULE_NAME)
-    target_compile_definitions(${MODULE_NAME} PRIVATE TT_APP_IO_WRAPS_STDIO)
+    target_link_options(${MODULE_NAME} PUBLIC
+        "-Wl,--wrap=read" "-Wl,--wrap=write" "-Wl,--wrap=close"
+        "-Wl,--wrap=printf" "-Wl,--wrap=fprintf" "-Wl,--wrap=vprintf" "-Wl,--wrap=vfprintf"
+        "-Wl,--wrap=puts" "-Wl,--wrap=fputs" "-Wl,--wrap=putchar" "-Wl,--wrap=fputc"
+        "-Wl,--wrap=getchar" "-Wl,--wrap=fgetc" "-Wl,--wrap=fgets"
+    )
 endif ()
 
 # install.cpp resolves an installed binary's fixed bin/<platform>/<binary>.so path itself, so it

Modules/app-module/source/io.cpp

@@ -8,13 +8,42 @@
 #include <cerrno>
 
 #if defined(TT_APP_IO_WRAPS_STDIO)
+#ifdef ESP_PLATFORM
+// Newlib's stdio (fflush()'s buffer-flush path, in particular) calls the reentrant _read_r/
+// _write_r/_close_r syscall stubs directly. The plain read()/write()/close() newlib provides are
+// just thin wrappers around them (esp-idf's components/newlib/src/syscalls.c: `write(fd, dst,
+// size) { return _write_r(__getreent(), fd, dst, size); }`). Wrapping the _r stubs catches both;
+// wrapping the plain names would only catch direct write()-style callers.
+#include <reent.h>
+extern "C" {
+ssize_t __real__read_r(struct _reent* r, int fd, void* buffer, size_t size);
+ssize_t __real__write_r(struct _reent* r, int fd, const void* buffer, size_t size);
+int __real__close_r(struct _reent* r, int fd);
+}
+namespace {
+ssize_t real_read(int fd, void* buffer, size_t size) { return __real__read_r(__getreent(), fd, buffer, size); }
+ssize_t real_write(int fd, const void* buffer, size_t size) { return __real__write_r(__getreent(), fd, buffer, size); }
+int real_close(int fd) { return __real__close_r(__getreent(), fd); }
+} // namespace
+#else
 extern "C" {
 ssize_t __real_read(int fd, void* buffer, size_t size);
 ssize_t __real_write(int fd, const void* buffer, size_t size);
 int __real_close(int fd);
 }
+namespace {
+ssize_t real_read(int fd, void* buffer, size_t size) { return __real_read(fd, buffer, size); }
+ssize_t real_write(int fd, const void* buffer, size_t size) { return __real_write(fd, buffer, size); }
+int real_close(int fd) { return __real_close(fd); }
+} // namespace
+#endif
 #else
 #include <unistd.h>
+namespace {
+ssize_t real_read(int fd, void* buffer, size_t size) { return ::read(fd, buffer, size); }
+ssize_t real_write(int fd, const void* buffer, size_t size) { return ::write(fd, buffer, size); }
+int real_close(int fd) { return ::close(fd); }
+} // namespace
 #endif
 
 namespace {
@@ -56,11 +85,7 @@ ssize_t app_io_read(int fd, void* buffer, size_t size) {
         errno = EBADF;
         return -1;
     }
-#if defined(TT_APP_IO_WRAPS_STDIO)
-    return __real_read(fd, buffer, size);
-#else
-    return ::read(fd, buffer, size);
-#endif
+    return real_read(fd, buffer, size);
 }
 
 ssize_t app_io_write(int fd, const void* buffer, size_t size) {
@@ -78,22 +103,14 @@ ssize_t app_io_write(int fd, const void* buffer, size_t size) {
         // output is currently being intercepted. Without this, a log line emitted while any app
         // instance has its stdout captured would vanish from the console entirely instead of
         // just also being visible to the capturing parent.
-#if defined(TT_APP_IO_WRAPS_STDIO)
-        __real_write(fd, buffer, size);
-#else
-        ::write(fd, buffer, size);
-#endif
+        real_write(fd, buffer, size);
         return result;
     }
     if (table != nullptr && app_fd_table_is_app_owned(table, fd)) {
         errno = EBADF;
         return -1;
     }
-#if defined(TT_APP_IO_WRAPS_STDIO)
-    return __real_write(fd, buffer, size);
-#else
-    return ::write(fd, buffer, size);
-#endif
+    return real_write(fd, buffer, size);
 }
 
 int app_io_close(int fd) {
@@ -108,11 +125,7 @@ int app_io_close(int fd) {
             return -1;
         }
     }
-#if defined(TT_APP_IO_WRAPS_STDIO)
-    return __real_close(fd);
-#else
-    return ::close(fd);
-#endif
+    return real_close(fd);
 }
 
 } // extern "C"

Modules/app-module/source/scheduler.cpp

@@ -32,8 +32,10 @@ constexpr size_t APP_INSTANCE_ID_THREAD_SLOT_INDEX = 1;
 // Matches TactilityKernel's Thread wrapper's THREAD_PRIORITY_NORMAL.
 constexpr UBaseType_t APP_TASK_PRIORITY = 4;
 
-// Used when an app's manifest doesn't request a specific stack depth (0). 8192 bytes' worth.
-constexpr size_t APP_DEFAULT_STACK_DEPTH = 8192 / sizeof(StackType_t);
+// Used when an app's manifest doesn't request a specific stack depth (0). 12288 bytes' worth.
+// Existing window-manager app manifests request at least 2400 words (9600 bytes); use a
+// conservative default above that baseline so a zero-depth app task cannot exhaust its stack.
+constexpr size_t APP_DEFAULT_STACK_DEPTH = 12288 / sizeof(StackType_t);
 
 // Task control blocks must stay in internal RAM; only the stack itself may live in external memory.
 constexpr MemoryPolicy APP_TASK_TCB_POLICY = { MEMORY_CAPABILITY_INTERNAL, 0, 0 };

Modules/app-module/source/stdio_wrap.cpp

@@ -0,0 +1,327 @@
+// SPDX-License-Identifier: Apache-2.0
+
+// Paired with -Wl,--wrap= on POSIX (this module's own CMakeLists.txt) and ESP32 (top-level
+// CMakeLists.txt); self-registered via dyld interpose below on Apple, whose linker doesn't
+// support --wrap.
+#include <app/io.h>
+
+#include <sys/types.h>
+
+#ifdef ESP_PLATFORM
+
+// Newlib's own stdio (fflush()'s buffer-flush path, in particular) calls the reentrant
+// _read_r/_write_r/_close_r syscall stubs directly, not the plain read()/write()/close() newlib
+// itself provides as thin wrappers around them (see e.g. esp-idf's components/newlib/src/
+// syscalls.c: `write(fd, dst, size) { return _write_r(__getreent(), fd, dst, size); }`)
+// Wrapping the plain names only catches direct write()-style callers, not newlib's own internal
+// stdio calls, so the _r stubs are wrapped here instead.
+#include <reent.h>
+
+extern "C" {
+
+ssize_t __wrap__read_r(struct _reent* r, int fd, void* buffer, size_t size) {
+    (void)r;
+    return app_io_read(fd, buffer, size);
+}
+
+ssize_t __wrap__write_r(struct _reent* r, int fd, const void* buffer, size_t size) {
+    (void)r;
+    return app_io_write(fd, buffer, size);
+}
+
+int __wrap__close_r(struct _reent* r, int fd) {
+    (void)r;
+    return app_io_close(fd);
+}
+
+}
+
+#else
+
+extern "C" {
+
+ssize_t __wrap_read(int fd, void* buffer, size_t size) {
+    return app_io_read(fd, buffer, size);
+}
+
+ssize_t __wrap_write(int fd, const void* buffer, size_t size) {
+    return app_io_write(fd, buffer, size);
+}
+
+int __wrap_close(int fd) {
+    return app_io_close(fd);
+}
+
+}
+
+#endif // ESP_PLATFORM
+
+#ifdef __APPLE__
+
+// --wrap also synthesizes __real_read/write/close automatically; dyld interpose doesn't, so
+// io.cpp's TT_APP_IO_WRAPS_STDIO fallback needs them defined here. dlsym(RTLD_NEXT, ...) is the
+// standard way to reach the true libSystem implementation despite the interpose below: a direct
+// call to read/write/close from this file would just recurse into __wrap_read/write/close, since
+// interpose rewrites every reference to those symbols in the process, this file included.
+#include <dlfcn.h>
+#include <unistd.h>
+
+extern "C" {
+
+ssize_t __real_read(int fd, void* buffer, size_t size) {
+    static auto real = reinterpret_cast<ssize_t (*)(int, void*, size_t)>(dlsym(RTLD_NEXT, "read"));
+    return real(fd, buffer, size);
+}
+
+ssize_t __real_write(int fd, const void* buffer, size_t size) {
+    static auto real = reinterpret_cast<ssize_t (*)(int, const void*, size_t)>(dlsym(RTLD_NEXT, "write"));
+    return real(fd, buffer, size);
+}
+
+int __real_close(int fd) {
+    static auto real = reinterpret_cast<int (*)(int)>(dlsym(RTLD_NEXT, "close"));
+    return real(fd);
+}
+
+}
+
+// <mach-o/dyld-interposing.h> isn't a public SDK header (it ships with dyld's own source, not
+// Xcode/Command Line Tools), so this reimplements its DYLD_INTERPOSE macro locally; reused below
+// for the printf-family interposes too.
+#define TT_DYLD_INTERPOSE(replacement, replacee) \
+    __attribute__((used)) static struct { const void* replacement; const void* replacee; } \
+        tt_interpose_##replacee __attribute__((section("__DATA,__interpose"))) = { \
+            (const void*)(unsigned long)&(replacement), (const void*)(unsigned long)&(replacee) \
+        };
+
+TT_DYLD_INTERPOSE(__wrap_read, read)
+TT_DYLD_INTERPOSE(__wrap_write, write)
+TT_DYLD_INTERPOSE(__wrap_close, close)
+
+#endif // __APPLE__
+
+// region glibc stdio wraps
+//
+// libc's printf/fprintf/etc are compiled into the C library and call an internal, non-exported
+// write() alias, which --wrap=write/the read/write/close interpose above can't reach: only calls
+// WE make to the public symbol. These wraps instead redirect calls WE make to printf/fprintf/etc,
+// the same trick as read/write/close above. Newlib (ESP-IDF) doesn't have this gap: its stdio does
+// call the wrappable syscall stubs, so this block is POSIX-only.
+//
+// Scoped to the printf/getc families only: fread/fwrite take an arbitrary FILE* and are already
+// used sitewide for real file I/O (e.g. File.cpp's readBinaryInternal), so wrapping them would
+// route every such call through this file's stdin/stdout check, a correctness risk for unrelated
+// code that isn't worth taking here. putc/getc are excluded too since libc defines them as
+// macros, not real calls, so wrapping those symbols wouldn't reliably intercept them.
+
+#if !defined(ESP_PLATFORM)
+
+#include <cstdarg>
+#include <cstdio>
+#include <cstring>
+#include <memory>
+#include <unistd.h>
+
+extern "C" {
+int __real_vfprintf(FILE* stream, const char* format, va_list args);
+int __real_fputs(const char* s, FILE* stream);
+int __real_fputc(int c, FILE* stream);
+int __real_fgetc(FILE* stream);
+char* __real_fgets(char* buffer, int size, FILE* stream);
+}
+
+#ifdef __APPLE__
+
+// --wrap synthesizes these automatically elsewhere; on Apple they're defined here via
+// dlsym(RTLD_NEXT, ...) instead. See the read/write/close __real_* block above for why.
+#include <dlfcn.h>
+
+extern "C" {
+
+int __real_vfprintf(FILE* stream, const char* format, va_list args) {
+    static auto real = reinterpret_cast<int (*)(FILE*, const char*, va_list)>(dlsym(RTLD_NEXT, "vfprintf"));
+    return real(stream, format, args);
+}
+
+int __real_fputs(const char* s, FILE* stream) {
+    static auto real = reinterpret_cast<int (*)(const char*, FILE*)>(dlsym(RTLD_NEXT, "fputs"));
+    return real(s, stream);
+}
+
+int __real_fputc(int c, FILE* stream) {
+    static auto real = reinterpret_cast<int (*)(int, FILE*)>(dlsym(RTLD_NEXT, "fputc"));
+    return real(c, stream);
+}
+
+int __real_fgetc(FILE* stream) {
+    static auto real = reinterpret_cast<int (*)(FILE*)>(dlsym(RTLD_NEXT, "fgetc"));
+    return real(stream);
+}
+
+char* __real_fgets(char* buffer, int size, FILE* stream) {
+    static auto real = reinterpret_cast<char* (*)(char*, int, FILE*)>(dlsym(RTLD_NEXT, "fgets"));
+    return real(buffer, size, stream);
+}
+
+}
+
+#endif // __APPLE__
+
+namespace {
+
+void writeAllToStdout(const void* data, size_t size) {
+    const auto* bytes = static_cast<const char*>(data);
+    size_t remaining = size;
+    while (remaining > 0) {
+        ssize_t written = app_io_write(STDOUT_FILENO, bytes, remaining);
+        if (written <= 0) {
+            break;
+        }
+        bytes += written;
+        remaining -= static_cast<size_t>(written);
+    }
+}
+
+// Formats into stdout via app_io_write() rather than through a FILE*'s own buffering, since that
+// buffering is exactly what glibc's internal write() call sidesteps --wrap for in the first place.
+int formatToStdout(const char* format, va_list args) {
+    char stackBuffer[256];
+    va_list argsForStack;
+    va_copy(argsForStack, args);
+    int needed = vsnprintf(stackBuffer, sizeof(stackBuffer), format, argsForStack);
+    va_end(argsForStack);
+    if (needed < 0) {
+        return needed;
+    }
+    if (static_cast<size_t>(needed) < sizeof(stackBuffer)) {
+        writeAllToStdout(stackBuffer, static_cast<size_t>(needed));
+        return needed;
+    }
+    auto heapBuffer = std::make_unique<char[]>(static_cast<size_t>(needed) + 1);
+    va_list argsForHeap;
+    va_copy(argsForHeap, args);
+    vsnprintf(heapBuffer.get(), static_cast<size_t>(needed) + 1, format, argsForHeap);
+    va_end(argsForHeap);
+    writeAllToStdout(heapBuffer.get(), static_cast<size_t>(needed));
+    return needed;
+}
+
+int readOneFromStdin(char& out) {
+    return static_cast<int>(app_io_read(STDIN_FILENO, &out, 1));
+}
+
+} // namespace
+
+extern "C" {
+
+int __wrap_vprintf(const char* format, va_list args) {
+    return formatToStdout(format, args);
+}
+
+int __wrap_printf(const char* format, ...) {
+    va_list args;
+    va_start(args, format);
+    int result = formatToStdout(format, args);
+    va_end(args);
+    return result;
+}
+
+int __wrap_vfprintf(FILE* stream, const char* format, va_list args) {
+    if (stream == stdout) {
+        return formatToStdout(format, args);
+    }
+    return __real_vfprintf(stream, format, args);
+}
+
+int __wrap_fprintf(FILE* stream, const char* format, ...) {
+    va_list args;
+    va_start(args, format);
+    int result = (stream == stdout) ? formatToStdout(format, args) : __real_vfprintf(stream, format, args);
+    va_end(args);
+    return result;
+}
+
+int __wrap_puts(const char* s) {
+    writeAllToStdout(s, strlen(s));
+    writeAllToStdout("\n", 1);
+    return 0;
+}
+
+int __wrap_fputs(const char* s, FILE* stream) {
+    if (stream == stdout) {
+        writeAllToStdout(s, strlen(s));
+        return 0;
+    }
+    return __real_fputs(s, stream);
+}
+
+int __wrap_putchar(int c) {
+    auto ch = static_cast<char>(c);
+    writeAllToStdout(&ch, 1);
+    return c;
+}
+
+int __wrap_fputc(int c, FILE* stream) {
+    if (stream == stdout) {
+        return __wrap_putchar(c);
+    }
+    return __real_fputc(c, stream);
+}
+
+int __wrap_getchar() {
+    char c;
+    return readOneFromStdin(c) == 1 ? static_cast<unsigned char>(c) : EOF;
+}
+
+int __wrap_fgetc(FILE* stream) {
+    if (stream == stdin) {
+        return __wrap_getchar();
+    }
+    return __real_fgetc(stream);
+}
+
+char* __wrap_fgets(char* buffer, int size, FILE* stream) {
+    if (stream != stdin) {
+        return __real_fgets(buffer, size, stream);
+    }
+    if (size <= 0) {
+        return nullptr;
+    }
+    int i = 0;
+    for (; i < size - 1; ++i) {
+        char c;
+        if (readOneFromStdin(c) != 1) {
+            break;
+        }
+        buffer[i] = c;
+        if (c == '\n') {
+            ++i;
+            break;
+        }
+    }
+    if (i == 0) {
+        return nullptr;
+    }
+    buffer[i] = '\0';
+    return buffer;
+}
+
+}
+
+#ifdef __APPLE__
+TT_DYLD_INTERPOSE(__wrap_vprintf, vprintf)
+TT_DYLD_INTERPOSE(__wrap_printf, printf)
+TT_DYLD_INTERPOSE(__wrap_vfprintf, vfprintf)
+TT_DYLD_INTERPOSE(__wrap_fprintf, fprintf)
+TT_DYLD_INTERPOSE(__wrap_puts, puts)
+TT_DYLD_INTERPOSE(__wrap_fputs, fputs)
+TT_DYLD_INTERPOSE(__wrap_putchar, putchar)
+TT_DYLD_INTERPOSE(__wrap_fputc, fputc)
+TT_DYLD_INTERPOSE(__wrap_getchar, getchar)
+TT_DYLD_INTERPOSE(__wrap_fgetc, fgetc)
+TT_DYLD_INTERPOSE(__wrap_fgets, fgets)
+#endif // __APPLE__
+
+#endif // !ESP_PLATFORM
+
+// endregion

Modules/app-module/tests/CMakeLists.txt

@@ -6,30 +6,12 @@ enable_language(C CXX ASM)
 file(GLOB_RECURSE TEST_SOURCES CONFIGURE_DEPENDS ${PROJECT_SOURCE_DIR}/source/*.cpp)
 add_executable(AppModuleTests EXCLUDE_FROM_ALL ${TEST_SOURCES})
 
-if (NOT APPLE)
-    # Provides __wrap_read/write/close for the -Wl,--wrap= below (see Tactility/CMakeLists.txt
-    # for the canonical pairing of this file with those flags).
-    target_sources(AppModuleTests PRIVATE ${CMAKE_CURRENT_LIST_DIR}/../../../Tactility/Source/AppStdioWrap.cpp)
-endif ()
-
 target_include_directories(AppModuleTests PRIVATE ${DOCTESTINC} ${CMAKE_CURRENT_LIST_DIR}/../private)
 
 add_test(NAME AppModuleTests COMMAND AppModuleTests)
 
-# Matches app-module's own TT_APP_IO_WRAPS_STDIO (see Modules/app-module/CMakeLists.txt):
-# io.cpp calls __real_read/write/close() on non-Apple POSIX, so any final link of it needs
-# these wraps too, or those symbols go unresolved. The printf-family/getc-family flags are
-# needed for the same reason: AppStdioWrap.cpp compiles those __wrap_* functions unconditionally
-# on this platform (see its own #if guard), and they reference __real_vfprintf/fputs/fputc/
-# fgetc/fgets - those only exist once the matching --wrap flag is passed.
-if (NOT APPLE)
-    target_link_options(AppModuleTests PRIVATE
-        "-Wl,--wrap=read" "-Wl,--wrap=write" "-Wl,--wrap=close"
-        "-Wl,--wrap=printf" "-Wl,--wrap=fprintf" "-Wl,--wrap=vprintf" "-Wl,--wrap=vfprintf"
-        "-Wl,--wrap=puts" "-Wl,--wrap=fputs" "-Wl,--wrap=putchar" "-Wl,--wrap=fputc"
-        "-Wl,--wrap=getchar" "-Wl,--wrap=fgetc" "-Wl,--wrap=fgets"
-    )
-endif ()
+# No --wrap flags or stdio_wrap.cpp source needed here: linking app-module below already brings
+# both along (see its own CMakeLists.txt).
 
 target_link_libraries(AppModuleTests PUBLIC
     TactilityKernel

Modules/app-module/tests/source/execute_test.cpp

@@ -15,6 +15,7 @@
 #include <tactility/delay.h>
 #include <tactility/freertos/task.h>
 
+#include <cstdio>
 #include <cstdlib>
 #include <cstring>
 #include <string>
@@ -110,6 +111,11 @@ int32_t stream_writer_app_main(int, char*[]) {
     return 7;
 }
 
+int32_t printf_stream_writer_app_main(int, char*[]) {
+    printf("loc");
+    return 7;
+}
+
 // Writes argv[0] to its own stdout, for the app_execute_with_streams() argv-delivery test.
 int32_t argv_echo_app_main(int argc, char* argv[]) {
     if (argc < 1) {
@@ -321,3 +327,53 @@ TEST_CASE("app_execute_for_result_with_streams delivers both the stream data and
     app_manager_stop(parent_id);
     app_manager_remove("test.app.execute.parent_streams");
 }
+
+TEST_CASE("app_execute_for_result_with_streams pipes a child's plain printf() calls too") {
+    ensure_memory_loader_registered();
+
+    AppManifest parent_manifest { "test.app.execute.printf_parent", "Parent", APP_CATEGORY_USER, { APP_LOCATION_MEMORY, reinterpret_cast<void*>(location_app_main) } };
+    REQUIRE_EQ(app_manager_add(&parent_manifest), ERROR_NONE);
+
+    uint32_t parent_id = 0;
+    REQUIRE_EQ(app_start("test.app.execute.printf_parent", 0, nullptr, &parent_id), ERROR_NONE);
+    CHECK(wait_for_state(parent_id, APP_INSTANCE_STATE_ACTIVE, 1000));
+
+    TaskEventGroup parent_event_group {};
+    task_event_group_construct(&parent_event_group);
+    AppEventSubscription parent_sub {};
+    REQUIRE_EQ(app_event_subscribe_with_app_id(&parent_sub, &parent_event_group, parent_id), ERROR_NONE);
+
+    uint8_t storage[64];
+    AppStream child_stdout {};
+    AppStreamBinding binding { STDOUT_FILENO, &child_stdout, storage, sizeof(storage), &parent_event_group };
+
+    AppLocation location { APP_LOCATION_MEMORY, reinterpret_cast<void*>(printf_stream_writer_app_main) };
+    uint32_t child_id = 0;
+    REQUIRE_EQ(app_execute_for_result_with_streams(location, AppStackConfig {}, 0, nullptr, &binding, 1, parent_id, &child_id), ERROR_NONE);
+
+    std::vector<uint8_t> received;
+    while (app_stream_await(&child_stdout, APP_FILE_WAIT_READABLE, pdMS_TO_TICKS(1000)) == ERROR_NONE) {
+        uint8_t chunk[16];
+        size_t n = app_stream_read(&child_stdout, chunk, sizeof(chunk));
+        if (n == 0) {
+            break; // EOF
+        }
+        received.insert(received.end(), chunk, chunk + n);
+    }
+    REQUIRE_EQ(received.size(), 3u);
+    CHECK_EQ(std::memcmp(received.data(), "loc", 3), 0);
+
+    REQUIRE_EQ(task_event_group_wait(&parent_event_group, parent_sub.bit, false, nullptr, pdMS_TO_TICKS(2000)), ERROR_NONE);
+    AppEvent event {};
+    REQUIRE_EQ(app_event_poll(&parent_sub, &event), ERROR_NONE);
+    CHECK_EQ(event.type, APP_EVENT_RESULT);
+    CHECK_EQ(event.result.launch_id, child_id);
+    CHECK_EQ(event.result.result, 7);
+
+    app_stream_unsubscribe(&child_stdout);
+    app_event_unsubscribe(&parent_sub);
+    task_event_group_destruct(&parent_event_group);
+    app_manager_stop(child_id);
+    app_manager_stop(parent_id);
+    app_manager_remove("test.app.execute.printf_parent");
+}

Modules/app-module/tests/source/io_test.cpp

@@ -16,6 +16,7 @@
 #include <unistd.h>
 
 #include <atomic>
+#include <cstdio>
 #include <cstring>
 #include <vector>
 
@@ -66,6 +67,11 @@ int32_t stdout_writer_app_main(int, char*[]) {
     return 0;
 }
 
+int32_t stdout_printf_app_main(int, char*[]) {
+    printf("hello");
+    return 0;
+}
+
 std::atomic<bool> g_blocked_writer_saw_error { false };
 std::atomic<bool> g_blocked_writer_done { false };
 
@@ -180,6 +186,41 @@ TEST_CASE("app_start_with_streams pipes a child's app_io_write() calls into a pa
     app_manager_remove("test.io.writer");
 }
 
+TEST_CASE("app_start_with_streams pipes a child's plain printf() calls into a parent-owned AppStream") {
+    ensure_memory_loader_registered();
+
+    AppManifest manifest { "test.io.printf_writer", "PrintfWriter", APP_CATEGORY_USER, { APP_LOCATION_MEMORY, reinterpret_cast<void*>(stdout_printf_app_main) } };
+    REQUIRE_EQ(app_manager_add(&manifest), ERROR_NONE);
+
+    TaskEventGroup event_group {};
+    task_event_group_construct(&event_group);
+
+    uint8_t storage[64];
+    AppStream child_stdout {};
+
+    AppStreamBinding binding { STDOUT_FILENO, &child_stdout, storage, sizeof(storage), &event_group };
+    AppInstanceId child_id = 0;
+    REQUIRE_EQ(app_start_with_streams("test.io.printf_writer", &binding, 1, &child_id), ERROR_NONE);
+
+    std::vector<uint8_t> received;
+    while (app_stream_await(&child_stdout, APP_FILE_WAIT_READABLE, pdMS_TO_TICKS(1000)) == ERROR_NONE) {
+        uint8_t chunk[16];
+        size_t n = app_stream_read(&child_stdout, chunk, sizeof(chunk));
+        if (n == 0) {
+            break; // EOF
+        }
+        received.insert(received.end(), chunk, chunk + n);
+    }
+
+    REQUIRE_EQ(received.size(), 5u);
+    CHECK_EQ(std::memcmp(received.data(), "hello", 5), 0);
+
+    REQUIRE(wait_for_state(child_id, APP_INSTANCE_STATE_STOPPED, 1000));
+    app_stream_unsubscribe(&child_stdout);
+    task_event_group_destruct(&event_group);
+    app_manager_remove("test.io.printf_writer");
+}
+
 TEST_CASE("a write blocked on a full stream wakes with an error once the consumer closes it") {
     ensure_memory_loader_registered();
     g_blocked_writer_saw_error.store(false, std::memory_order_relaxed);

Modules/lvgl-module/include/lvgl/fonts.h

@@ -14,6 +14,15 @@ enum LvglFontSize {
     FONT_SIZE_LARGE,
 };
 
+enum LvglFontScale {
+    FONT_SCALE_SMALL,
+    FONT_SCALE_DEFAULT,
+    FONT_SCALE_LARGE,
+};
+
+void lvgl_set_text_font_scale(enum LvglFontScale font_scale);
+enum LvglFontScale lvgl_get_text_font_scale(void);
+
 const lv_font_t* lvgl_get_shared_icon_font(void);
 uint32_t lvgl_get_shared_icon_font_height(void);
 

Modules/lvgl-module/source/fonts.c

@@ -13,8 +13,30 @@ extern const lv_font_t TT_LVGL_LAUNCHER_FONT_ICON_SYMBOL;
 extern const lv_font_t TT_LVGL_STATUSBAR_FONT_ICON_SYMBOL;
 extern const lv_font_t TT_LVGL_SHARED_FONT_ICON_SYMBOL;
 
+static enum LvglFontScale text_font_scale = FONT_SCALE_DEFAULT;
+
+void lvgl_set_text_font_scale(enum LvglFontScale font_scale) {
+    check(font_scale >= FONT_SCALE_SMALL && font_scale <= FONT_SCALE_LARGE);
+    text_font_scale = font_scale;
+}
+
+enum LvglFontScale lvgl_get_text_font_scale(void) {
+    return text_font_scale;
+}
+
+static enum LvglFontSize resolve_text_font_size(enum LvglFontSize font_size) {
+    int resolved = (int)font_size + (int)text_font_scale - (int)FONT_SCALE_DEFAULT;
+    if (resolved < FONT_SIZE_SMALL) {
+        return FONT_SIZE_SMALL;
+    }
+    if (resolved > FONT_SIZE_LARGE) {
+        return FONT_SIZE_LARGE;
+    }
+    return (enum LvglFontSize)resolved;
+}
+
 uint32_t lvgl_get_text_font_height(enum LvglFontSize font_size) {
-    switch (font_size) {
+    switch (resolve_text_font_size(font_size)) {
         case FONT_SIZE_SMALL: return TT_LVGL_TEXT_FONT_SMALL_SIZE;
         case FONT_SIZE_DEFAULT: return TT_LVGL_TEXT_FONT_DEFAULT_SIZE;
         case FONT_SIZE_LARGE: return TT_LVGL_TEXT_FONT_LARGE_SIZE;
@@ -22,7 +44,7 @@ uint32_t lvgl_get_text_font_height(enum LvglFontSize font_size) {
     }
 }
 const lv_font_t* lvgl_get_text_font(enum LvglFontSize font_size) {
-    switch (font_size) {
+    switch (resolve_text_font_size(font_size)) {
         case FONT_SIZE_SMALL: return &TT_LVGL_TEXT_FONT_SMALL_SYMBOL;
         case FONT_SIZE_DEFAULT: return &TT_LVGL_TEXT_FONT_DEFAULT_SYMBOL;
         case FONT_SIZE_LARGE: return &TT_LVGL_TEXT_FONT_LARGE_SYMBOL;

Modules/lvgl-module/source/symbols.c

@@ -26,6 +26,8 @@ const struct ModuleSymbol lvgl_module_symbols[] = {
     DEFINE_MODULE_SYMBOL(lvgl_module),
     DEFINE_MODULE_SYMBOL(lvgl_module_configure),
     // lvgl_fonts
+    DEFINE_MODULE_SYMBOL(lvgl_set_text_font_scale),
+    DEFINE_MODULE_SYMBOL(lvgl_get_text_font_scale),
     DEFINE_MODULE_SYMBOL(lvgl_get_shared_icon_font),
     DEFINE_MODULE_SYMBOL(lvgl_get_shared_icon_font_height),
     DEFINE_MODULE_SYMBOL(lvgl_get_text_font),
@@ -494,6 +496,12 @@ const struct ModuleSymbol lvgl_module_symbols[] = {
     // lv_image
     DEFINE_MODULE_SYMBOL(lv_image_create),
     DEFINE_MODULE_SYMBOL(lv_image_set_src),
+    DEFINE_MODULE_SYMBOL(lv_image_set_scale),
+    DEFINE_MODULE_SYMBOL(lv_image_set_scale_x),
+    DEFINE_MODULE_SYMBOL(lv_image_set_scale_y),
+    DEFINE_MODULE_SYMBOL(lv_image_get_scale),
+    DEFINE_MODULE_SYMBOL(lv_image_get_scale_x),
+    DEFINE_MODULE_SYMBOL(lv_image_get_scale_y),
     // lv_anim
     DEFINE_MODULE_SYMBOL(lv_anim_init),
     DEFINE_MODULE_SYMBOL(lv_anim_set_duration),

Platforms/platform-posix/CMakeLists.txt

@@ -6,3 +6,12 @@ add_library(platform-posix OBJECT)
 target_sources(platform-posix PRIVATE ${SOURCES})
 #target_include_directories(platform-posix PUBLIC include/)
 target_link_libraries(platform-posix PUBLIC TactilityKernel)
+
+# Routes every pthread_attr_setstack() call to __wrap_pthread_attr_setstack() in source/pthread_stack_wrap.c,
+# which no-ops it. see that file for why.
+# --wrap is a GNU ld option; Apple's linker doesn't support it, so that file instead self-registers a dyld interpose
+# for this symbol on Apple, needing no link flag. PUBLIC so every consumer of this OBJECT library
+# (Tactility, and every test target that links platform-posix directly) gets it applied too.
+if (NOT APPLE)
+    target_link_options(platform-posix PUBLIC "-Wl,--wrap=pthread_attr_setstack")
+endif ()

Platforms/platform-posix/source/pthread_stack_wrap.c

@@ -2,20 +2,15 @@
 #include <stddef.h>
 
 /**
- * Linked in with -Wl,--wrap=pthread_attr_setstack (see Tactility/CMakeLists.txt).
+ * FreeRTOS's POSIX port hands every task a stack carved from its own heap (pvPortMalloc) via this call.
+ * pthread_attr_setstack requires page alignment that pvPortMalloc doesn't guarantee.
+ * When it succeeds anyway, the task's real pthread stack ends up living inside that small FreeRTOS heap region,
+ * where a thread doing heavier stack work (e.g. Mesa GL shader compilation) can silently corrupt adjacent heap_4 objects.
+ * No-op'ing the call instead leaves every task's pthread_attr_t at its pthread_attr_init() default,
+ * so pthread_create() gives it a real, properly sized stack.
  *
- * FreeRTOS's POSIX port (Libraries/FreeRTOS-Kernel/portable/ThirdParty/GCC/Posix/port.c)
- * hands every task a stack carved out of its own heap (pvPortMalloc) via this call.
- * pthread_attr_setstack requires page alignment, which pvPortMalloc doesn't guarantee;
- * when it happens to succeed anyway (allocator alignment can vary run to run), the
- * task's real pthread stack ends up living inside that small FreeRTOS heap region -
- * fine for typical embedded task code, but a desktop GL driver doing on-the-fly shader
- * compilation on that thread (e.g. Mesa on first frame present) can overflow it and
- * silently corrupt adjacent heap_4 objects.
- *
- * Wrapping the call out entirely (rather than patching the vendored port.c) leaves every
- * task's pthread_attr_t at its pthread_attr_init() default, so pthread_create() always
- * gives it a real, properly allocated default-size stack instead.
+ * Linked via -Wl,--wrap=pthread_attr_setstack (this module's own CMakeLists.txt) on non-Apple
+ * platforms; reused as a dyld interpose target below on Apple platforms, whose linker lacks --wrap.
  */
 int __wrap_pthread_attr_setstack(pthread_attr_t* attr, void* stackaddr, size_t stacksize) {
     (void)attr;
@@ -23,3 +18,17 @@ int __wrap_pthread_attr_setstack(pthread_attr_t* attr, void* stackaddr, size_t s
     (void)stacksize;
     return 0;
 }
+
+#ifdef __APPLE__
+
+// <mach-o/dyld-interposing.h> isn't a public SDK header (it ships with dyld's own source, not
+// Xcode/Command Line Tools), so this reimplements its DYLD_INTERPOSE macro locally.
+#define TT_DYLD_INTERPOSE(replacement, replacee) \
+    __attribute__((used)) static struct { const void* replacement; const void* replacee; } \
+        tt_interpose_##replacee __attribute__((section("__DATA,__interpose"))) = { \
+            (const void*)(unsigned long)&(replacement), (const void*)(unsigned long)&(replacee) \
+        };
+
+TT_DYLD_INTERPOSE(__wrap_pthread_attr_setstack, pthread_attr_setstack)
+
+#endif

Tactility/CMakeLists.txt

@@ -185,31 +185,9 @@ else ()
     # Exports Tactility's own symbols (-rdynamic) so a dlopen()ed app-posix-module app can resolve
     # calls back into it - the OS-native equivalent of app-esp32-module's custom symbol resolver.
     set_target_properties(Tactility PROPERTIES ENABLE_EXPORTS ON)
-    # Routes every pthread_attr_setstack() call (FreeRTOS's POSIX port hands each task a stack
-    # carved out of its own heap through this) to __wrap_pthread_attr_setstack() in
-    # Platforms/platform-posix/source/pthread_stack_wrap.c, which no-ops it - see that file for why.
-    # --wrap is a GNU ld option; Apple's linker doesn't support it.
-    if (NOT APPLE)
-        target_link_options(Tactility PRIVATE "-Wl,--wrap=pthread_attr_setstack")
-        # Routes every read()/write()/close() call to Tactility/Source/AppStdioWrap.cpp's
-        # __wrap_read/write/close(), which forward into app_io_read/write/close() - the fd-table
-        # dispatch that lets an app's own stdio (e.g. a fileselection dialog's printf'd result
-        # path) reach an AppStream a parent bound via app_manager_start_with_streams(). Mirrors
-        # what ESP-IDF's build already does for the ESP32 target (see top-level CMakeLists.txt).
-        target_link_options(Tactility PRIVATE "-Wl,--wrap=read" "-Wl,--wrap=write" "-Wl,--wrap=close")
-        # glibc's printf/fprintf/etc don't call the public write() symbol internally (they're
-        # already compiled into libc.so, out of --wrap's reach), so the read/write/close wrap
-        # above can't see them. Newlib (ESP-IDF) doesn't have this gap - its stdio does call the
-        # wrappable syscall stubs - so this block is POSIX-only. Wrapping these symbols instead
-        # redirects OUR OWN calls to them (the only ones --wrap can rewrite) through
-        # AppStdioWrap.cpp's __wrap_* functions, which check the target stream (stdout/stdin) and
-        # fall back to the real libc function for any other FILE*.
-        target_link_options(Tactility PRIVATE
-            "-Wl,--wrap=printf" "-Wl,--wrap=fprintf" "-Wl,--wrap=vprintf" "-Wl,--wrap=vfprintf"
-            "-Wl,--wrap=puts" "-Wl,--wrap=fputs" "-Wl,--wrap=putchar" "-Wl,--wrap=fputc"
-            "-Wl,--wrap=getchar" "-Wl,--wrap=fgetc" "-Wl,--wrap=fgets"
-        )
-    endif ()
+    # pthread_attr_setstack and read/write/close/printf-family aren't wrapped here: linking
+    # platform-posix and app-module already brings those wraps along (see their own
+    # CMakeLists.txt files).
 endif ()
 
 #

Tactility/Include/Tactility/lvgl/Lvgl.h

@@ -1,5 +1,9 @@
 #pragma once
 
+namespace tt::settings::display {
+enum class FontSize;
+}
+
 namespace tt::lvgl {
 
 #ifdef ESP_PLATFORM
@@ -12,6 +16,9 @@ static constexpr auto* PATH_PREFIX = "A:/";
 
 bool isStarted();
 
+/** Applies the selected semantic text size to the LVGL theme and future widgets. */
+void applyFontSize(settings::display::FontSize fontSize);
+
 void start();
 
 void stop();

Tactility/Include/Tactility/settings/DisplaySettings.h

@@ -18,16 +18,34 @@ enum class ScreensaverType {
     Mystify,
     MatrixRain,
     StackChan,
+    McpScreen,
+    BibleVerse,     // Launch the Bible Verse app (if installed)
     Count           // Sentinel for bounds checking - must be last
 };
 
+enum class FontSize {
+    Small,
+    Default,
+    Large,
+    Count
+};
+
 struct DisplaySettings {
     Orientation orientation;
+    FontSize fontSize = FontSize::Default;
     uint8_t gammaCurve;
     uint8_t backlightDuty;
     bool backlightTimeoutEnabled;
     uint32_t backlightTimeoutMs; // 0 = Never
     ScreensaverType screensaverType = ScreensaverType::BouncingBalls;
+    // Night dim: when enabled and the local hour falls inside
+    // [nightDimStartHour, nightDimEndHour), the screensaver runs at
+    // nightDimDuty instead of backlightDuty. A start == end window
+    // means the whole day.
+    bool nightDimEnabled = false;
+    uint8_t nightDimStartHour = 22;
+    uint8_t nightDimEndHour = 7;
+    uint8_t nightDimDuty = 20;
 };
 
 /** Compares default settings with the function parameter to return the difference */

Tactility/Include/Tactility/settings/McpSettings.h

@@ -0,0 +1,14 @@
+#pragma once
+
+namespace tt::settings::mcp {
+
+struct McpSettings {
+    bool mcpEnabled = false;            // Enable MCP server endpoints on system web server
+};
+
+bool load(McpSettings& settings);
+McpSettings getDefault();
+McpSettings loadOrGetDefault();
+bool save(const McpSettings& settings);
+
+} // namespace tt::settings::mcp

Tactility/Include/Tactility/settings/SystemSettings.h

@@ -6,7 +6,7 @@ namespace tt::settings {
 
 struct SystemSettings {
     Language language = Language::en_US;
-    bool timeFormat24h = true;
+    bool timeFormat24h = false;
     std::string dateFormat = std::string("DD/MM/YYYY"); // MM/DD/YYYY, DD/MM/YYYY, YYYY-MM-DD, YYYY/MM/DD
 };
 

Tactility/Private/Tactility/app/files/SupportedFiles.h

@@ -7,5 +7,6 @@ namespace tt::app::files {
 bool isSupportedAppFile(const std::string& filename);
 bool isSupportedImageFile(const std::string& filename);
 bool isSupportedTextFile(const std::string& filename);
+bool isSupportedAudioFile(const std::string& filename);
 
 } // namespace

Tactility/Private/Tactility/mcp/McpSystem.h

@@ -0,0 +1,77 @@
+#pragma once
+#ifdef ESP_PLATFORM
+
+#include <lvgl.h>
+#include <mutex>
+#include <string>
+#include <vector>
+#include <tactility/device.h>
+#include <tactility/drivers/audio_stream.h>
+
+namespace tt::mcp {
+
+struct McpSystemState {
+    std::mutex mutex;
+    bool overrideActive = false;
+    
+    // UI elements when McpOverrideApp is active
+    lv_obj_t* drawArea = nullptr;
+    uint16_t* framebuffer = nullptr;
+    size_t framebufferSize = 0;
+    uint16_t displayWidth = 320;
+    uint16_t displayHeight = 240;
+    uint16_t drawWidth = 320;
+    uint16_t drawHeight = 240;
+    int drawColor = 1; // 0 = white, 1 = black
+    
+    // Audio device status
+    Device* i2sDevice = nullptr;
+    Device* audioStreamDevice = nullptr;
+    AudioStreamHandle audioHandle = nullptr;
+    volatile bool audioBusy = false;
+    volatile bool audioRunning = false; // Used to abort play/record loop
+
+    // Video streaming state
+    volatile bool streamRunning = false;
+    void* streamTaskHandle = nullptr; // use void* to avoid freertos header inclusion dependency
+    uint32_t framesDrawn = 0;
+    uint32_t tcpBytesReceived = 0;
+    uint32_t lastDrawMs = 0;
+    double lastFps = 0.0;
+};
+
+McpSystemState& getState();
+
+bool clearScreen(int color);
+bool drawText(const std::string& text, int x, int y, int size);
+bool drawRgb565(const uint8_t* data, size_t size, int x, int y, int w, int h);
+bool drawBmp(const uint8_t* data, size_t size, int x, int y);
+bool drawPbm(const uint8_t* data, size_t size, int x, int y);
+std::string getScreenshotPbmBase64();
+
+bool playTone(int frequency, int durationMs, int volume, std::string& error);
+bool recordVoice(int durationSec, const std::string& filename, size_t& recordedBytes, std::string& error);
+bool playAudioFile(const std::string& filename, int volume, std::string& error);
+bool playWavMemory(const uint8_t* data, size_t size, int volume, std::string& error);
+bool playMp3File(const std::string& filename, int volume, std::string& error);
+bool playMp3Memory(const uint8_t* data, size_t size, int volume, std::string& error);
+
+bool getBatteryStatus(double& voltage_v, int& percentage_pct, std::string& error);
+bool setLedColor(int r, int g, int b, const std::string& mode, std::string& error);
+bool getSensors(double& temp_c, double& hum_pct, std::string& imu_json, std::string& error);
+bool scanBleDevices(int duration_ms, std::string& devices_json, std::string& error);
+bool writeSdFile(const std::string& filename, const std::string& content, std::string& error);
+bool readSdFile(const std::string& filename, std::string& content, std::string& error);
+bool downloadSdFile(const std::string& url, const std::string& filename, std::string& error);
+
+bool startVideoStreamServer();
+void stopVideoStreamServer();
+bool getVideoStreamStats(std::string& stats_json);
+
+bool listApps(std::string& apps_json, std::string& error);
+bool runApp(const std::string& appId, std::string& error);
+bool listSdFiles(const std::string& directory, std::string& files_json, std::string& error);
+
+} // namespace tt::mcp
+
+#endif

Tactility/Private/Tactility/service/displayidle/DisplayIdleService.h

@@ -5,6 +5,8 @@
 #include <Tactility/settings/DisplaySettings.h>
 #include <Tactility/Timer.h>
 
+#include <app/instance.h>
+
 #include <atomic>
 #include <memory>
 
@@ -29,9 +31,15 @@ class DisplayIdleService final : public Service {
     // Active screensaver instance
     std::unique_ptr<Screensaver> screensaver;
 
-    // Screensaver auto-off: turn off backlight after 5 minutes of screensaver
+    // App launched as screensaver (Bible Verse): instance id, 0 when none.
+    // A separate flag (not just the id) tracks intent, so a user-closed app
+    // doesn't look like an active screensaver and vice versa.
+    AppInstanceId screensaverAppInstanceId = 0;
+    bool screensaverAppActive = false;
+
+    // Screensaver auto-off: turn off backlight after 30 minutes of screensaver
     static constexpr uint32_t TICK_INTERVAL_MS = 50;
-    static constexpr uint32_t SCREENSAVER_AUTO_OFF_MS = 5 * 60 * 1000;  // 5 minutes
+    static constexpr uint32_t SCREENSAVER_AUTO_OFF_MS = 30 * 60 * 1000;  // 30 minutes
     static constexpr int SCREENSAVER_AUTO_OFF_TICKS = SCREENSAVER_AUTO_OFF_MS / TICK_INTERVAL_MS;
     int screensaverActiveCounter = 0;
     bool backlightOff = false;
@@ -63,6 +71,7 @@ public:
      *       arbitrary threads while the timer is running.
      */
     void stopScreensaver();
+    void startMcpScreensaver();
 
     /**
      * Check if the screensaver is currently active.

Tactility/Private/Tactility/service/webserver/WebServerService.h

@@ -81,6 +81,12 @@ private:
     static error_t handleApiAppsInstall(struct HttpServerRequest* request, void* user_ctx);
     static error_t handleApiWifi(struct HttpServerRequest* request, void* user_ctx);
     static error_t handleApiScreenshot(struct HttpServerRequest* request, void* user_ctx);
+    static error_t handleApiSimTouch(struct HttpServerRequest* request, void* user_ctx);
+    static error_t handleSimViewer(struct HttpServerRequest* request, void* user_ctx);
+    static error_t handleApiMcp(struct HttpServerRequest* request, void* user_ctx);
+#ifdef ESP_PLATFORM
+    static error_t handleApiScreenRaw(struct HttpServerRequest* request, void* user_ctx);
+#endif
 
     // Dynamic asset serving
     static error_t handleAssets(struct HttpServerRequest* request, void* user_ctx);

Tactility/Source/AppStdioWrap.cpp

@@ -1,200 +0,0 @@
-// SPDX-License-Identifier: Apache-2.0
-
-// Paired with -Wl,--wrap=read/write/close - see Tactility/CMakeLists.txt (POSIX) and the
-// top-level CMakeLists.txt (ESP32) for where that's applied. On a platform where it isn't
-// (currently: macOS, whose linker doesn't support --wrap), these are simply never called - real
-// read()/write()/close() calls go straight through unredirected.
-#include <app/io.h>
-
-#include <sys/types.h>
-
-extern "C" {
-
-ssize_t __wrap_read(int fd, void* buffer, size_t size) {
-    return app_io_read(fd, buffer, size);
-}
-
-ssize_t __wrap_write(int fd, const void* buffer, size_t size) {
-    return app_io_write(fd, buffer, size);
-}
-
-int __wrap_close(int fd) {
-    return app_io_close(fd);
-}
-
-}
-
-// region glibc stdio wraps
-//
-// glibc's printf/fprintf/etc are compiled into libc.so and call an internal, non-exported write()
-// alias - --wrap=write (above) can't reach that call, only calls WE make to the public symbol.
-// These wraps instead redirect calls WE make to printf/fprintf/etc, the same trick as read/write/
-// close above. Newlib (ESP-IDF) doesn't have this gap - its stdio does call the wrappable syscall
-// stubs - so Tactility/CMakeLists.txt only applies the matching -Wl,--wrap= flags on POSIX.
-//
-// Scoped to the printf/getc families only: fread/fwrite take an arbitrary FILE* and are already
-// used sitewide for real file I/O (e.g. File.cpp's readBinaryInternal), so wrapping them would
-// route every such call through this file's stdin/stdout check - a correctness risk for unrelated
-// code that isn't worth taking here. putc/getc are excluded too since glibc defines them as
-// macros, not real calls, so wrapping those symbols wouldn't reliably intercept them.
-
-#if !defined(ESP_PLATFORM) && !defined(__APPLE__)
-
-#include <cstdarg>
-#include <cstdio>
-#include <cstring>
-#include <memory>
-#include <unistd.h>
-
-extern "C" {
-int __real_vfprintf(FILE* stream, const char* format, va_list args);
-int __real_fputs(const char* s, FILE* stream);
-int __real_fputc(int c, FILE* stream);
-int __real_fgetc(FILE* stream);
-char* __real_fgets(char* buffer, int size, FILE* stream);
-}
-
-namespace {
-
-void writeAllToStdout(const void* data, size_t size) {
-    const auto* bytes = static_cast<const char*>(data);
-    size_t remaining = size;
-    while (remaining > 0) {
-        ssize_t written = app_io_write(STDOUT_FILENO, bytes, remaining);
-        if (written <= 0) {
-            break;
-        }
-        bytes += written;
-        remaining -= static_cast<size_t>(written);
-    }
-}
-
-// Formats into stdout via app_io_write() rather than through a FILE*'s own buffering, since that
-// buffering is exactly what glibc's internal write() call sidesteps --wrap for in the first place.
-int formatToStdout(const char* format, va_list args) {
-    char stackBuffer[256];
-    va_list argsForStack;
-    va_copy(argsForStack, args);
-    int needed = vsnprintf(stackBuffer, sizeof(stackBuffer), format, argsForStack);
-    va_end(argsForStack);
-    if (needed < 0) {
-        return needed;
-    }
-    if (static_cast<size_t>(needed) < sizeof(stackBuffer)) {
-        writeAllToStdout(stackBuffer, static_cast<size_t>(needed));
-        return needed;
-    }
-    auto heapBuffer = std::make_unique<char[]>(static_cast<size_t>(needed) + 1);
-    va_list argsForHeap;
-    va_copy(argsForHeap, args);
-    vsnprintf(heapBuffer.get(), static_cast<size_t>(needed) + 1, format, argsForHeap);
-    va_end(argsForHeap);
-    writeAllToStdout(heapBuffer.get(), static_cast<size_t>(needed));
-    return needed;
-}
-
-int readOneFromStdin(char& out) {
-    return static_cast<int>(app_io_read(STDIN_FILENO, &out, 1));
-}
-
-} // namespace
-
-extern "C" {
-
-int __wrap_vprintf(const char* format, va_list args) {
-    return formatToStdout(format, args);
-}
-
-int __wrap_printf(const char* format, ...) {
-    va_list args;
-    va_start(args, format);
-    int result = formatToStdout(format, args);
-    va_end(args);
-    return result;
-}
-
-int __wrap_vfprintf(FILE* stream, const char* format, va_list args) {
-    if (stream == stdout) {
-        return formatToStdout(format, args);
-    }
-    return __real_vfprintf(stream, format, args);
-}
-
-int __wrap_fprintf(FILE* stream, const char* format, ...) {
-    va_list args;
-    va_start(args, format);
-    int result = (stream == stdout) ? formatToStdout(format, args) : __real_vfprintf(stream, format, args);
-    va_end(args);
-    return result;
-}
-
-int __wrap_puts(const char* s) {
-    writeAllToStdout(s, strlen(s));
-    writeAllToStdout("\n", 1);
-    return 0;
-}
-
-int __wrap_fputs(const char* s, FILE* stream) {
-    if (stream == stdout) {
-        writeAllToStdout(s, strlen(s));
-        return 0;
-    }
-    return __real_fputs(s, stream);
-}
-
-int __wrap_putchar(int c) {
-    auto ch = static_cast<char>(c);
-    writeAllToStdout(&ch, 1);
-    return c;
-}
-
-int __wrap_fputc(int c, FILE* stream) {
-    if (stream == stdout) {
-        return __wrap_putchar(c);
-    }
-    return __real_fputc(c, stream);
-}
-
-int __wrap_getchar() {
-    char c;
-    return readOneFromStdin(c) == 1 ? static_cast<unsigned char>(c) : EOF;
-}
-
-int __wrap_fgetc(FILE* stream) {
-    if (stream == stdin) {
-        return __wrap_getchar();
-    }
-    return __real_fgetc(stream);
-}
-
-char* __wrap_fgets(char* buffer, int size, FILE* stream) {
-    if (stream != stdin) {
-        return __real_fgets(buffer, size, stream);
-    }
-    if (size <= 0) {
-        return nullptr;
-    }
-    int i = 0;
-    for (; i < size - 1; ++i) {
-        char c;
-        if (readOneFromStdin(c) != 1) {
-            break;
-        }
-        buffer[i] = c;
-        if (c == '\n') {
-            ++i;
-            break;
-        }
-    }
-    if (i == 0) {
-        return nullptr;
-    }
-    buffer[i] = '\0';
-    return buffer;
-}
-
-}
-
-#endif // !ESP_PLATFORM && !__APPLE__
-
-// endregion

Tactility/Source/Tactility.cpp

@@ -40,6 +40,7 @@
 #include <Tactility/file/File.h>
 #include <Tactility/hal/SdCard.h>
 #include <Tactility/lvgl/KeyboardDeviceListener.h>
+#include <Tactility/lvgl/Lvgl.h>
 #include <Tactility/lvgl/Statusbar.h>
 #include <Tactility/lvgl/TrackballInit.h>
 #include <Tactility/lvgl/UsbHidInput.h>
@@ -189,9 +190,12 @@ namespace app {
 #ifdef ESP_PLATFORM
     namespace apwebserver { extern const ::AppManifest manifest; }
     namespace crashdiagnostics { extern const ::AppManifest manifest; }
+    namespace mcpsettings { extern const ::AppManifest manifest; }
 #if CONFIG_TT_TDECK_WORKAROUND == 1
     namespace keyboardsettings { extern const ::AppManifest manifest; } // T-Deck only for now
 #endif
+#else
+    namespace mcpsettings { extern const ::AppManifest manifest; }
 #endif
 
     namespace trackballsettings { extern const ::AppManifest manifest; } // T-Deck only for now
@@ -250,11 +254,14 @@ static void registerInternalApps() {
     app_manager_add(&app::development::manifest);
     app_manager_add(&app::webserversettings::manifest);
 #ifdef ESP_PLATFORM
+    app_manager_add(&app::mcpsettings::manifest);
     app_manager_add(&app::apwebserver::manifest);
     app_manager_add(&app::crashdiagnostics::manifest);
 #if defined(CONFIG_TT_TDECK_WORKAROUND)
         app_manager_add(&app::keyboardsettings::manifest);
 #endif
+#else
+    app_manager_add(&app::mcpsettings::manifest);
 #endif
 
     if (device_exists_of_type(&TRACKBALL_TYPE)) {
@@ -433,6 +440,7 @@ static void onLvglStarted() {
     if (auto* display = lv_display_get_default(); display != nullptr) {
         auto displaySettings = settings::display::loadOrGetDefault();
         lv_display_set_rotation(display, settings::display::toLvglDisplayRotation(displaySettings.orientation));
+        lvgl::applyFontSize(displaySettings.fontSize);
     }
     lvgl_unlock();
 

Tactility/Source/app/apphub/AppHubApp.cpp

@@ -107,6 +107,9 @@ void showNoInternet(Context* ctx) {
 }
 
 void showApps(Context* ctx) {
+    if (ctx->contentWrapper == nullptr) {
+        return;
+    }
     // Refresh rebuilds the list from scratch (cached copy, then again once the network fetch
     // lands), which would otherwise reset the user's scroll position each time.
     int32_t scrollY;
@@ -266,7 +269,9 @@ void createWidgets(lv_obj_t* parent, void* userData) {
 
 void destroyWidgets(void* userData) {
     auto* ctx = static_cast<Context*>(userData);
-    ctx->scrollY = lv_obj_get_scroll_y(ctx->contentWrapper);
+    if (ctx->contentWrapper != nullptr) {
+        ctx->scrollY = lv_obj_get_scroll_y(ctx->contentWrapper);
+    }
     ctx->contentWrapper = nullptr;
     ctx->refreshButton = nullptr;
 }
@@ -334,7 +339,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.apphub",
     .name = "App Hub",
     .category = APP_CATEGORY_SYSTEM,
-    .location = {APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain)}
+    .location = {APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain)},
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace tt::app::apphub

Tactility/Source/app/applist/AppList.cpp

@@ -121,7 +121,7 @@ extern const ::AppManifest manifest = {
     .category = APP_CATEGORY_SYSTEM,
     .location = { .type = APP_LOCATION_MEMORY, .location = reinterpret_cast<void*>(appMain) },
     .flags = APP_MANIFEST_FLAG_HIDDEN,
-    .stack = { .depth = 2400, .desired_memory_capability = 0 },
+    .stack = { .depth = 3072, .desired_memory_capability = 0 },
 };
 
 } // namespace

Tactility/Source/app/btmanage/BtManage.cpp

@@ -245,7 +245,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.btmanage",
     .name = "Bluetooth",
     .category = APP_CATEGORY_SETTINGS,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace tt::app::btmanage

Tactility/Source/app/chat/ChatApp.cpp

@@ -228,7 +228,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.chat",
     .name = "Chat",
     .category = APP_CATEGORY_USER,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace tt::app::chat

Tactility/Source/app/development/Development.cpp

@@ -230,7 +230,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.development",
     .name = "Development",
     .category = APP_CATEGORY_SETTINGS,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace

Tactility/Source/app/display/Display.cpp

@@ -10,6 +10,7 @@
 #ifdef ESP_PLATFORM
 #include <Tactility/service/displayidle/DisplayIdleService.h>
 #endif
+#include <Tactility/lvgl/Lvgl.h>
 #include <Tactility/settings/DisplaySettings.h>
 
 #include <app/event.h>
@@ -41,6 +42,10 @@ struct Context {
     lv_obj_t* timeoutSwitch = nullptr;
     lv_obj_t* timeoutDropdown = nullptr;
     lv_obj_t* screensaverDropdown = nullptr;
+    lv_obj_t* nightDimSwitch = nullptr;
+    lv_obj_t* nightDimStartDropdown = nullptr;
+    lv_obj_t* nightDimEndDropdown = nullptr;
+    lv_obj_t* nightDimDutySlider = nullptr;
 };
 
 
@@ -90,6 +95,21 @@ void onOrientationSet(lv_event_t* event) {
     }
 }
 
+void onFontSizeChanged(lv_event_t* event) {
+    auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
+    auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
+    uint32_t selected_index = lv_dropdown_get_selected(dropdown);
+    if (selected_index >= static_cast<uint32_t>(settings::display::FontSize::Count)) {
+        return;
+    }
+    auto selected_size = static_cast<settings::display::FontSize>(selected_index);
+    if (selected_size != ctx->displaySettings.fontSize) {
+        ctx->displaySettings.fontSize = selected_size;
+        ctx->displaySettingsUpdated = true;
+        lvgl::applyFontSize(selected_size);
+    }
+}
+
 void onTimeoutSwitch(lv_event_t* event) {
     auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
     auto* sw = static_cast<lv_obj_t*>(lv_event_get_target(event));
@@ -115,8 +135,8 @@ void onTimeoutChanged(lv_event_t* event) {
     auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
     auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
     uint32_t idx = lv_dropdown_get_selected(dropdown);
-    // Map dropdown index to ms: 0=15s,1=30s,2=1m,3=2m,4=5m,5=Never
-    static const uint32_t values_ms[] = {15000, 30000, 60000, 120000, 300000, 0};
+    // Map dropdown index to ms: 0=15s,1=30s,2=1m,3=2m,4=5m,5=15m,6=30m,7=Never
+    static const uint32_t values_ms[] = {15000, 30000, 60000, 120000, 300000, 900000, 1800000, 0};
     if (idx < (sizeof(values_ms)/sizeof(values_ms[0]))) {
         ctx->displaySettings.backlightTimeoutMs = values_ms[idx];
         ctx->displaySettingsUpdated = true;
@@ -138,6 +158,82 @@ void onScreensaverChanged(lv_event_t* event) {
     }
 }
 
+static void setNightDimControlsEnabled(Context* ctx, bool enabled) {
+    if (ctx->nightDimStartDropdown != nullptr) {
+        if (enabled) {
+            lv_obj_clear_state(ctx->nightDimStartDropdown, LV_STATE_DISABLED);
+        } else {
+            lv_obj_add_state(ctx->nightDimStartDropdown, LV_STATE_DISABLED);
+        }
+    }
+    if (ctx->nightDimEndDropdown != nullptr) {
+        if (enabled) {
+            lv_obj_clear_state(ctx->nightDimEndDropdown, LV_STATE_DISABLED);
+        } else {
+            lv_obj_add_state(ctx->nightDimEndDropdown, LV_STATE_DISABLED);
+        }
+    }
+    if (ctx->nightDimDutySlider != nullptr) {
+        if (enabled) {
+            lv_obj_clear_state(ctx->nightDimDutySlider, LV_STATE_DISABLED);
+        } else {
+            lv_obj_add_state(ctx->nightDimDutySlider, LV_STATE_DISABLED);
+        }
+    }
+}
+
+static const char* hourOptions() {
+    // 00..23, one per line
+    static const char* options =
+        "00\n01\n02\n03\n04\n05\n06\n07\n08\n09\n10\n11\n"
+        "12\n13\n14\n15\n16\n17\n18\n19\n20\n21\n22\n23";
+    return options;
+}
+
+void onNightDimSwitch(lv_event_t* event) {
+    auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
+    auto* sw = static_cast<lv_obj_t*>(lv_event_get_target(event));
+    bool enabled = lv_obj_has_state(sw, LV_STATE_CHECKED);
+    ctx->displaySettings.nightDimEnabled = enabled;
+    ctx->displaySettingsUpdated = true;
+    setNightDimControlsEnabled(ctx, enabled);
+}
+
+void onNightDimStartChanged(lv_event_t* event) {
+    auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
+    auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
+    uint32_t idx = lv_dropdown_get_selected(dropdown);
+    if (idx > 23) {
+        return;
+    }
+    ctx->displaySettings.nightDimStartHour = static_cast<uint8_t>(idx);
+    ctx->displaySettingsUpdated = true;
+}
+
+void onNightDimEndChanged(lv_event_t* event) {
+    auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
+    auto* dropdown = static_cast<lv_obj_t*>(lv_event_get_target(event));
+    uint32_t idx = lv_dropdown_get_selected(dropdown);
+    if (idx > 23) {
+        return;
+    }
+    ctx->displaySettings.nightDimEndHour = static_cast<uint8_t>(idx);
+    ctx->displaySettingsUpdated = true;
+}
+
+void onNightDimDutyChanged(lv_event_t* event) {
+    auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
+    auto* slider = static_cast<lv_obj_t*>(lv_event_get_target(event));
+    int32_t value = lv_slider_get_value(slider);
+    if (value < 0) {
+        value = 0;
+    } else if (value > 255) {
+        value = 255;
+    }
+    ctx->displaySettings.nightDimDuty = static_cast<uint8_t>(value);
+    ctx->displaySettingsUpdated = true;
+}
+
 void createWidgets(lv_obj_t* parent, void* userData) {
     auto* ctx = static_cast<Context*>(userData);
 
@@ -208,6 +304,23 @@ void createWidgets(lv_obj_t* parent, void* userData) {
     // Set the dropdown to match current orientation enum
     lv_dropdown_set_selected(orientation_dropdown, static_cast<uint16_t>(ctx->displaySettings.orientation));
 
+    // Font size
+
+    auto* font_size_wrapper = lv_obj_create(main_wrapper);
+    lv_obj_set_size(font_size_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
+    lv_obj_set_style_pad_all(font_size_wrapper, 0, LV_STATE_DEFAULT);
+    lv_obj_set_style_border_width(font_size_wrapper, 0, LV_STATE_DEFAULT);
+
+    auto* font_size_label = lv_label_create(font_size_wrapper);
+    lv_label_set_text(font_size_label, "Font size");
+    lv_obj_align(font_size_label, LV_ALIGN_LEFT_MID, 0, 0);
+
+    auto* font_size_dropdown = lv_dropdown_create(font_size_wrapper);
+    lv_dropdown_set_options(font_size_dropdown, "Small\nDefault\nLarge");
+    lv_obj_align(font_size_dropdown, LV_ALIGN_RIGHT_MID, 0, 0);
+    lv_obj_add_event_cb(font_size_dropdown, onFontSizeChanged, LV_EVENT_VALUE_CHANGED, ctx);
+    lv_dropdown_set_selected(font_size_dropdown, static_cast<uint16_t>(ctx->displaySettings.fontSize));
+
     // Screen timeout
     // Note: DisplayIdleService doesn't act on these settings for kernel-driver displays yet
     // (it only looks up the deprecated tt::hal::display::DisplayDevice), so these currently
@@ -240,7 +353,7 @@ void createWidgets(lv_obj_t* parent, void* userData) {
         lv_obj_align(timeout_value_label, LV_ALIGN_LEFT_MID, 0, 0);
 
         ctx->timeoutDropdown = lv_dropdown_create(timeout_select_wrapper);
-        lv_dropdown_set_options(ctx->timeoutDropdown, "15 seconds\n30 seconds\n1 minute\n2 minutes\n5 minutes\nNever");
+        lv_dropdown_set_options(ctx->timeoutDropdown, "15 seconds\n30 seconds\n1 minute\n2 minutes\n5 minutes\n15 minutes\n30 minutes\nNever");
         lv_obj_align(ctx->timeoutDropdown, LV_ALIGN_RIGHT_MID, 0, 0);
         lv_obj_add_event_cb(ctx->timeoutDropdown, onTimeoutChanged, LV_EVENT_VALUE_CHANGED, ctx);
         // Initialize dropdown selection from settings
@@ -255,8 +368,12 @@ void createWidgets(lv_obj_t* parent, void* userData) {
             idx = 3;
         else if (ms == 300000)
             idx = 4;
-        else if (ms == 0)
+        else if (ms == 900000)
             idx = 5;
+        else if (ms == 1800000)
+            idx = 6;
+        else if (ms == 0)
+            idx = 7;
         lv_dropdown_set_selected(ctx->timeoutDropdown, idx);
         if (!ctx->displaySettings.backlightTimeoutEnabled) {
             lv_obj_add_state(ctx->timeoutDropdown, LV_STATE_DISABLED);
@@ -274,13 +391,78 @@ void createWidgets(lv_obj_t* parent, void* userData) {
 
         ctx->screensaverDropdown = lv_dropdown_create(screensaver_wrapper);
         // Note: order correlates with settings::display::ScreensaverType enum order
-        lv_dropdown_set_options(ctx->screensaverDropdown, "None\nBouncing Balls\nMystify\nMatrix Rain\nStackChan");
+    lv_dropdown_set_options(ctx->screensaverDropdown, "None\nBouncing Balls\nMystify\nMatrix Rain\nStackChan\nMCP Screen\nBible Verse");
         lv_obj_align(ctx->screensaverDropdown, LV_ALIGN_RIGHT_MID, 0, 0);
         lv_obj_add_event_cb(ctx->screensaverDropdown, onScreensaverChanged, LV_EVENT_VALUE_CHANGED, ctx);
         lv_dropdown_set_selected(ctx->screensaverDropdown, static_cast<uint16_t>(ctx->displaySettings.screensaverType));
         if (!ctx->displaySettings.backlightTimeoutEnabled) {
             lv_obj_add_state(ctx->screensaverDropdown, LV_STATE_DISABLED);
         }
+
+        // Night dim: dim the backlight while the screensaver is up, during a time window
+        auto* night_dim_wrapper = lv_obj_create(main_wrapper);
+        lv_obj_set_size(night_dim_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
+        lv_obj_set_style_pad_all(night_dim_wrapper, 0, LV_STATE_DEFAULT);
+        lv_obj_set_style_border_width(night_dim_wrapper, 0, LV_STATE_DEFAULT);
+
+        auto* night_dim_label = lv_label_create(night_dim_wrapper);
+        lv_label_set_text(night_dim_label, "Night dim");
+        lv_obj_align(night_dim_label, LV_ALIGN_LEFT_MID, 0, 0);
+
+        ctx->nightDimSwitch = lv_switch_create(night_dim_wrapper);
+        if (ctx->displaySettings.nightDimEnabled) {
+            lv_obj_add_state(ctx->nightDimSwitch, LV_STATE_CHECKED);
+        }
+        lv_obj_align(ctx->nightDimSwitch, LV_ALIGN_RIGHT_MID, 0, 0);
+        lv_obj_add_event_cb(ctx->nightDimSwitch, onNightDimSwitch, LV_EVENT_VALUE_CHANGED, ctx);
+
+        auto* night_dim_start_wrapper = lv_obj_create(main_wrapper);
+        lv_obj_set_size(night_dim_start_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
+        lv_obj_set_style_pad_all(night_dim_start_wrapper, 0, LV_STATE_DEFAULT);
+        lv_obj_set_style_border_width(night_dim_start_wrapper, 0, LV_STATE_DEFAULT);
+
+        auto* night_dim_start_label = lv_label_create(night_dim_start_wrapper);
+        lv_label_set_text(night_dim_start_label, "Dim from");
+        lv_obj_align(night_dim_start_label, LV_ALIGN_LEFT_MID, 0, 0);
+
+        ctx->nightDimStartDropdown = lv_dropdown_create(night_dim_start_wrapper);
+        lv_dropdown_set_options(ctx->nightDimStartDropdown, hourOptions());
+        lv_obj_align(ctx->nightDimStartDropdown, LV_ALIGN_RIGHT_MID, 0, 0);
+        lv_obj_add_event_cb(ctx->nightDimStartDropdown, onNightDimStartChanged, LV_EVENT_VALUE_CHANGED, ctx);
+        lv_dropdown_set_selected(ctx->nightDimStartDropdown, ctx->displaySettings.nightDimStartHour > 23 ? 0 : ctx->displaySettings.nightDimStartHour);
+
+        auto* night_dim_end_wrapper = lv_obj_create(main_wrapper);
+        lv_obj_set_size(night_dim_end_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
+        lv_obj_set_style_pad_all(night_dim_end_wrapper, 0, LV_STATE_DEFAULT);
+        lv_obj_set_style_border_width(night_dim_end_wrapper, 0, LV_STATE_DEFAULT);
+
+        auto* night_dim_end_label = lv_label_create(night_dim_end_wrapper);
+        lv_label_set_text(night_dim_end_label, "Dim until");
+        lv_obj_align(night_dim_end_label, LV_ALIGN_LEFT_MID, 0, 0);
+
+        ctx->nightDimEndDropdown = lv_dropdown_create(night_dim_end_wrapper);
+        lv_dropdown_set_options(ctx->nightDimEndDropdown, hourOptions());
+        lv_obj_align(ctx->nightDimEndDropdown, LV_ALIGN_RIGHT_MID, 0, 0);
+        lv_obj_add_event_cb(ctx->nightDimEndDropdown, onNightDimEndChanged, LV_EVENT_VALUE_CHANGED, ctx);
+        lv_dropdown_set_selected(ctx->nightDimEndDropdown, ctx->displaySettings.nightDimEndHour > 23 ? 0 : ctx->displaySettings.nightDimEndHour);
+
+        auto* night_dim_duty_wrapper = lv_obj_create(main_wrapper);
+        lv_obj_set_size(night_dim_duty_wrapper, LV_PCT(100), LV_SIZE_CONTENT);
+        lv_obj_set_style_pad_all(night_dim_duty_wrapper, 0, LV_STATE_DEFAULT);
+        lv_obj_set_style_border_width(night_dim_duty_wrapper, 0, LV_STATE_DEFAULT);
+
+        auto* night_dim_duty_label = lv_label_create(night_dim_duty_wrapper);
+        lv_label_set_text(night_dim_duty_label, "Dim brightness");
+        lv_obj_align(night_dim_duty_label, LV_ALIGN_LEFT_MID, 0, 0);
+
+        ctx->nightDimDutySlider = lv_slider_create(night_dim_duty_wrapper);
+        lv_obj_set_width(ctx->nightDimDutySlider, LV_PCT(50));
+        lv_obj_align(ctx->nightDimDutySlider, LV_ALIGN_RIGHT_MID, 0, 0);
+        lv_slider_set_range(ctx->nightDimDutySlider, 0, 255);
+        lv_slider_set_value(ctx->nightDimDutySlider, ctx->displaySettings.nightDimDuty, LV_ANIM_OFF);
+        lv_obj_add_event_cb(ctx->nightDimDutySlider, onNightDimDutyChanged, LV_EVENT_VALUE_CHANGED, ctx);
+
+        setNightDimControlsEnabled(ctx, ctx->displaySettings.nightDimEnabled);
     }
 }
 

Tactility/Source/app/files/SupportedFiles.cpp

@@ -26,4 +26,12 @@ bool isSupportedTextFile(const std::string& filename) {
         filename_lower.ends_with(".properties");
 }
 
+bool isSupportedAudioFile(const std::string& filename) {
+    std::string filename_lower = string::lowercase(filename);
+    return filename_lower.ends_with(".mp3") ||
+        filename_lower.ends_with(".wav") ||
+        filename_lower.ends_with(".ogg") ||
+        filename_lower.ends_with(".flac");
+}
+
 } // namespace tt::app::filebrowser

Tactility/Source/app/files/View.cpp

@@ -1,6 +1,7 @@
 #include <app/event.h>
 #include <app/execute.h>
 #include <app/install.h>
+#include <app/start.h>
 #include <app/stream.h>
 
 #include <lvgl/lvgl.h>
@@ -204,6 +205,15 @@ void View::viewFile(const std::string& path, const std::string& filename) {
             // Remove forward slash, because we need a relative path
             notes::start(file_path.substr(1));
         }
+    } else if (isSupportedAudioFile(filename)) {
+        // External MP3 player reads argv as key=value pairs (see
+        // CurrentAppCompat tt_app_start_with_bundle): file=<path>
+        std::string file_arg = "file=" + file_path;
+        const char* argv[] = { file_arg.c_str() };
+        uint32_t instance_id = 0;
+        if (app_start("one.tactility.mp3player", 1, argv, &instance_id) != ERROR_NONE) {
+            LOG_W(TAG, "Failed to start MP3 player for %s", file_path.c_str());
+        }
     } else if (isExecutablePath(file_path)) {
         runFile(file_path);
     } else {

Tactility/Source/app/fileselection/FileSelection.cpp

@@ -85,7 +85,7 @@ int32_t appMain(int argc, char* argv[]) {
 
     if (ctx.resultCode == 0) {
         // The parent captures this via an AppStream bound to our stdout (see startWithMode()) -
-        // see AppStdioWrap.cpp for how printf() itself gets routed there on POSIX.
+        // see Modules/app-module/source/stdio_wrap.cpp for how printf() itself gets routed there on POSIX.
         LOG_I(TAG, "Result: %s", ctx.resultPath.c_str());
         printf("%s", ctx.resultPath.c_str());
     }

Tactility/Source/app/i2cscanner/I2cScanner.cpp

@@ -426,7 +426,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.i2cscanner",
     .name = "I2C Scanner",
     .category = APP_CATEGORY_SYSTEM,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 uint32_t start() {

Tactility/Source/app/inputdialog/InputDialog.cpp

@@ -138,7 +138,7 @@ int32_t appMain(int argc, char* argv[]) {
 
     if (ctx.resultCode == 0) {
         // The caller captures this via an AppStream bound to our stdout (see start()); see
-        // AppStdioWrap.cpp for how printf() itself gets routed there on POSIX.
+        // Modules/app-module/source/stdio_wrap.cpp for how printf() itself gets routed there on POSIX.
         printf("%s", ctx.resultText.c_str());
     }
     return ctx.resultCode;

Tactility/Source/app/launcher/Launcher.cpp

@@ -4,11 +4,26 @@
 #include <app/scheduler.h>
 #include <app/start.h>
 
+#include <Tactility/DeprecatedPaths.h>
+#include <Tactility/MountPoints.h>
+#include <Tactility/Tactility.h>
+#include <Tactility/app/setup/Setup.h>
+#include <Tactility/file/File.h>
+#include <Tactility/lvgl/Lvgl.h>
+#include <Tactility/service/wifi/Wifi.h>
+#include <Tactility/settings/BootSettings.h>
+#include <Tactility/settings/Time.h>
+
+#include <algorithm>
+#include <cstdio>
 #include <cstring>
+#include <ctime>
+#include <string>
 
 #include <lvgl.h>
-#include <lvgl/icons/launcher.h>
 #include <lvgl/fonts.h>
+#include <lvgl/icons/launcher.h>
+#include <lvgl/icons/statusbar.h>
 #include <lvgl/lvgl.h>
 
 #include <lvgl_window_manager/window_manager.h>
@@ -20,64 +35,29 @@
 #include <tactility/log.h>
 #include <tactility/memory.h>
 
-#include <Tactility/app/setup/Setup.h>
-#include <Tactility/settings/BootSettings.h>
-#include <Tactility/Tactility.h>
-
 namespace tt::app::launcher {
 
 constexpr auto* TAG = "Launcher";
+constexpr auto* BACKGROUND_ASSET = "color-field.png";
+constexpr auto* CUSTOM_BACKGROUND_PATH = "tactility/launcher/background.bin";
+constexpr lv_color_t TEXT_COLOR = LV_COLOR_MAKE(0xF8, 0xF5, 0xF2);
+constexpr lv_color_t MUTED_TEXT_COLOR = LV_COLOR_MAKE(0xDF, 0xD6, 0xD3);
+constexpr lv_color_t ACCENT_COLOR = LV_COLOR_MAKE(0xEC, 0x75, 0x69);
 
 namespace {
 
-uint32_t getButtonPadding(UiDensity density, uint32_t buttonSize) {
-    if (density == LVGL_UI_DENSITY_COMPACT) {
-        return 0;
-    } else {
-        return buttonSize / 8;
-    }
-}
+struct LauncherWidgets {
+    lv_obj_t* timeLabel = nullptr;
+    lv_obj_t* dateLabel = nullptr;
+    lv_obj_t* dataLabel = nullptr;
+    lv_obj_t* statusLabel = nullptr;
+    lv_timer_t* updateTimer = nullptr;
+};
 
-int32_t computeButtonMargin(int32_t available_span, int32_t total_button_size) {
-    const int32_t usable = std::max<int32_t>(0, available_span - (3 * total_button_size));
-    return std::min<int32_t>(usable / 16, total_button_size / 2);
-}
-
-void onAppPressed(lv_event_t* e) {
-    auto* appId = static_cast<const char*>(lv_event_get_user_data(e));
+void onAppPressed(lv_event_t* event) {
+    const auto* app_id = static_cast<const char*>(lv_event_get_user_data(event));
     uint32_t instance_id = 0;
-    app_start(appId, 0, nullptr, &instance_id);
-}
-
-lv_obj_t* createAppButton(lv_obj_t* parent, UiDensity uiDensity, const char* imageFile, const char* appId, int32_t itemMargin, bool isLandscape) {
-    const auto button_size = lvgl_get_launcher_icon_font_height();
-    const auto button_padding = getButtonPadding(uiDensity, button_size);
-    auto* apps_button = lv_button_create(parent);
-
-    lv_obj_set_style_pad_all(apps_button, static_cast<int32_t>(button_padding), LV_STATE_DEFAULT);
-    if (isLandscape) {
-        lv_obj_set_style_margin_hor(apps_button, itemMargin, LV_STATE_DEFAULT);
-    } else {
-        lv_obj_set_style_margin_ver(apps_button, itemMargin, LV_STATE_DEFAULT);
-    }
-
-    lv_obj_set_style_shadow_width(apps_button, 0, LV_STATE_DEFAULT);
-    lv_obj_set_style_bg_opa(apps_button, 0, LV_STATE_DEFAULT);
-
-    // create the image first
-    auto* button_image = lv_image_create(apps_button);
-    lv_obj_set_style_text_font(button_image, lvgl_get_launcher_icon_font(), LV_STATE_DEFAULT);
-    lv_image_set_src(button_image, imageFile);
-    lv_obj_set_style_text_color(button_image, lv_theme_get_color_primary(button_image), LV_STATE_DEFAULT);
-    lv_obj_set_style_image_recolor(button_image, lv_theme_get_color_primary(parent), LV_STATE_DEFAULT);
-    lv_obj_set_style_image_recolor_opa(button_image, LV_OPA_COVER, LV_STATE_DEFAULT);
-
-    // Ensure it's square (Material Symbols are slightly wider than tall)
-    lv_obj_set_size(button_image, button_size, button_size);
-
-    lv_obj_add_event_cb(apps_button, onAppPressed, LV_EVENT_SHORT_CLICKED, (void*)appId);
-
-    return apps_button;
+    app_start(app_id, 0, nullptr, &instance_id);
 }
 
 bool shouldShowPowerButton() {
@@ -85,180 +65,288 @@ bool shouldShowPowerButton() {
     device_for_each_of_type(&POWER_SUPPLY_TYPE, &show_power_button, [](Device* device, void* context) {
         if (device_is_ready(device) && power_supply_supports_power_off(device)) {
             *static_cast<bool*>(context) = true;
-            return false; // stop iterating
-        } else {
-            return true; // continue iterating
+            return false;
         }
+        return true;
     });
     return show_power_button;
 }
 
-void onButtonsWrapperResized(lv_event_t* e);
+int getBatteryPercentage() {
+    Device* power = nullptr;
+    device_for_each_of_type(&POWER_SUPPLY_TYPE, &power, [](Device* device, void* context) {
+        if (device_is_ready(device) && power_supply_supports_property(device, POWER_SUPPLY_PROP_CAPACITY)) {
+            *static_cast<Device**>(context) = device;
+            return false;
+        }
+        return true;
+    });
+    if (power == nullptr) return -1;
 
-// The screen object outlives this window's own widgets (lvgl-window-manager deletes and
-// recreates only the topmost window's widget on every app switch, not the screen itself), so
-// the LV_EVENT_SIZE_CHANGED callback registered on it must be removed once buttons_wrapper is
-// destroyed, to avoid a dangling user-data pointer the next time the display rotates while a
-// different window is topmost.
-void onButtonsWrapperDeleted(lv_event_t* e) {
-    auto* buttons_wrapper = lv_event_get_target_obj(e);
-    auto* screen = lv_obj_get_screen(buttons_wrapper);
-    lv_obj_remove_event_cb_with_user_data(screen, onButtonsWrapperResized, buttons_wrapper);
+    PowerSupplyPropertyValue charge_level;
+    if (power_supply_get_property(power, POWER_SUPPLY_PROP_CAPACITY, &charge_level) != ERROR_NONE) return -1;
+    return std::clamp(charge_level.int_value, 0, 100);
 }
 
-// Re-applies the flex direction and per-button margins when the display orientation changes
-// while the launcher is the visible window (these are decided once at createWidgets() based on
-// the resolution at that time, so a later rotation needs this to catch up).
-void onButtonsWrapperResized(lv_event_t* e) {
-    auto* buttons_wrapper = static_cast<lv_obj_t*>(lv_event_get_user_data(e));
-    const auto* display = lv_obj_get_display(buttons_wrapper);
-
-    const auto button_size = lvgl_get_launcher_icon_font_height();
-    const auto button_padding = getButtonPadding(lvgl_get_ui_density(), button_size);
-    const auto total_button_size = button_size + (button_padding * 2);
-
-    const auto horizontal_px = lv_display_get_horizontal_resolution(display);
-    const auto vertical_px = lv_display_get_vertical_resolution(display);
-    const bool is_landscape_display = horizontal_px >= vertical_px;
-    const auto current_flow = lv_obj_get_style_flex_flow(buttons_wrapper, LV_PART_MAIN);
-    const bool was_landscape = current_flow == LV_FLEX_FLOW_ROW;
-    if (is_landscape_display == was_landscape) {
-        return;
-    }
-
-    lv_obj_set_flex_flow(buttons_wrapper, is_landscape_display ? LV_FLEX_FLOW_ROW : LV_FLEX_FLOW_COLUMN);
-
-    const int32_t margin = is_landscape_display
-        ? computeButtonMargin(horizontal_px, total_button_size)
-        : computeButtonMargin(vertical_px, total_button_size);
-
-    const uint32_t child_count = lv_obj_get_child_count(buttons_wrapper);
-    for (uint32_t i = 0; i < child_count; i++) {
-        auto* button = lv_obj_get_child(buttons_wrapper, i);
-        lv_obj_set_style_margin_hor(button, is_landscape_display ? margin : 0, LV_STATE_DEFAULT);
-        lv_obj_set_style_margin_ver(button, is_landscape_display ? 0 : margin, LV_STATE_DEFAULT);
+const char* getWifiStatusIcon(service::wifi::RadioState state) {
+    using enum service::wifi::RadioState;
+    switch (state) {
+        case ConnectionActive: return LVGL_ICON_STATUSBAR_SIGNAL_WIFI_4_BAR;
+        case Off:
+        case OffPending: return LVGL_ICON_STATUSBAR_SIGNAL_WIFI_OFF;
+        default: return LVGL_ICON_STATUSBAR_SIGNAL_WIFI_0_BAR;
     }
 }
 
-void createWidgets(lv_obj_t* parent, void*) {
-    auto* buttons_wrapper = lv_obj_create(parent);
+const char* getBatteryStatusIcon(int percentage) {
+    if (percentage < 0) return "";
+    if (percentage >= 95) return LVGL_ICON_STATUSBAR_BATTERY_ANDROID_FRAME_FULL;
+    if (percentage >= 64) return LVGL_ICON_STATUSBAR_BATTERY_ANDROID_FRAME_5;
+    if (percentage >= 32) return LVGL_ICON_STATUSBAR_BATTERY_ANDROID_FRAME_3;
+    return LVGL_ICON_STATUSBAR_BATTERY_ANDROID_FRAME_1;
+}
 
-    auto ui_density = lvgl_get_ui_density();
-    const auto button_size = lvgl_get_launcher_icon_font_height();
-    const auto button_padding = getButtonPadding(ui_density, button_size);
-    const auto total_button_size = button_size + (button_padding * 2);
+lv_obj_t* createAppButton(lv_obj_t* parent, const char* icon, const char* app_id, bool emphasized) {
+    auto* button = lv_button_create(parent);
+    lv_obj_set_size(button, 52, 52);
+    lv_obj_set_style_radius(button, 15, LV_PART_MAIN);
+    lv_obj_set_style_shadow_width(button, 0, LV_PART_MAIN);
+    lv_obj_set_style_border_width(button, emphasized ? 2 : 1, LV_PART_MAIN);
+    lv_obj_set_style_border_color(button, emphasized ? ACCENT_COLOR : lv_color_hex(0x746568), LV_PART_MAIN);
+    lv_obj_set_style_border_opa(button, emphasized ? LV_OPA_COVER : LV_OPA_60, LV_PART_MAIN);
+    lv_obj_set_style_bg_color(button, lv_color_hex(0x211B20), LV_PART_MAIN);
+    lv_obj_set_style_bg_opa(button, emphasized ? LV_OPA_80 : LV_OPA_70, LV_PART_MAIN);
+    lv_obj_set_style_bg_color(button, lv_color_hex(0x392C32), LV_STATE_PRESSED);
+    lv_obj_set_style_transform_scale(button, 238, LV_STATE_PRESSED);
+    lv_obj_set_style_outline_color(button, ACCENT_COLOR, LV_STATE_FOCUSED);
+    lv_obj_set_style_outline_width(button, 2, LV_STATE_FOCUSED);
+    lv_obj_set_style_outline_pad(button, 2, LV_STATE_FOCUSED);
 
-    lv_obj_align(buttons_wrapper, LV_ALIGN_CENTER, 0, 0);
-    lv_obj_set_size(buttons_wrapper, LV_SIZE_CONTENT, LV_SIZE_CONTENT);
-    lv_obj_set_style_border_width(buttons_wrapper, 0, LV_STATE_DEFAULT);
-    lv_obj_set_flex_grow(buttons_wrapper, 1);
+    auto* image = lv_image_create(button);
+    lv_obj_set_size(image, 36, 36);
+    lv_obj_center(image);
+    lv_obj_set_style_text_font(image, lvgl_get_launcher_icon_font(), LV_STATE_DEFAULT);
+    lv_image_set_src(image, icon);
+    lv_obj_set_style_image_recolor(image, TEXT_COLOR, LV_STATE_DEFAULT);
+    lv_obj_set_style_image_recolor_opa(image, LV_OPA_COVER, LV_STATE_DEFAULT);
+    lv_obj_add_event_cb(button, onAppPressed, LV_EVENT_SHORT_CLICKED, const_cast<char*>(app_id));
+    return button;
+}
 
-    // Fix for button selection
-    lv_obj_set_style_pad_all(buttons_wrapper, 6, LV_STATE_DEFAULT);
-
-    const auto* display = lv_obj_get_display(parent);
-    const auto horizontal_px = lv_display_get_horizontal_resolution(display);
-    const auto vertical_px = lv_display_get_vertical_resolution(display);
-    const bool is_landscape_display = horizontal_px >= vertical_px;
-    if (is_landscape_display) {
-        lv_obj_set_flex_flow(buttons_wrapper, LV_FLEX_FLOW_ROW);
+void updateInformation(LauncherWidgets& widgets) {
+    const std::time_t now = std::time(nullptr);
+    std::tm local_time {};
+    localtime_r(&now, &local_time);
+    char time_buffer[12];
+    char date_buffer[40];
+    if (local_time.tm_year >= 125) {
+        if (settings::isTimeFormat24Hour()) {
+            std::strftime(time_buffer, sizeof(time_buffer), "%H:%M", &local_time);
+        } else {
+            std::strftime(time_buffer, sizeof(time_buffer), "%I:%M", &local_time);
+            if (time_buffer[0] == '0') std::memmove(time_buffer, time_buffer + 1, std::strlen(time_buffer));
+        }
+        std::strftime(date_buffer, sizeof(date_buffer), "%A, %B %e", &local_time);
     } else {
-        lv_obj_set_flex_flow(buttons_wrapper, LV_FLEX_FLOW_COLUMN);
+        std::strcpy(time_buffer, "--:--");
+        std::strcpy(date_buffer, "Set date and time");
+    }
+    lv_label_set_text(widgets.timeLabel, time_buffer);
+    lv_label_set_text(widgets.dateLabel, date_buffer);
+
+    const auto wifi_state = service::wifi::getRadioState();
+    std::string sd_card_path;
+    const bool sd_ready = findFirstMountedSdCardPath(sd_card_path);
+    const int battery_percentage = getBatteryPercentage();
+    char data_buffer[80];
+    if (battery_percentage >= 0) {
+        std::snprintf(data_buffer, sizeof(data_buffer), "%s  •  %s  •  %d%%",
+            wifi_state == service::wifi::RadioState::ConnectionActive ? "Wi-Fi connected" : "Wi-Fi offline",
+            sd_ready ? "SD ready" : "No SD", battery_percentage);
+    } else {
+        std::snprintf(data_buffer, sizeof(data_buffer), "%s  •  %s",
+            wifi_state == service::wifi::RadioState::ConnectionActive ? "Wi-Fi connected" : "Wi-Fi offline",
+            sd_ready ? "SD ready" : "No SD");
+    }
+    lv_label_set_text(widgets.dataLabel, data_buffer);
+
+    char status_buffer[24];
+    std::snprintf(status_buffer, sizeof(status_buffer), "%s%s", getWifiStatusIcon(wifi_state), getBatteryStatusIcon(battery_percentage));
+    lv_label_set_text(widgets.statusLabel, status_buffer);
+}
+
+void onUpdateTimer(lv_timer_t* timer) {
+    updateInformation(*static_cast<LauncherWidgets*>(lv_timer_get_user_data(timer)));
+}
+
+std::string getDefaultBackgroundPath() {
+    return std::string(file::MOUNT_POINT_SYSTEM) + "/app/Launcher/assets/" + BACKGROUND_ASSET;
+}
+
+void createWidgets(lv_obj_t* parent, void* user_data) {
+    auto& widgets = *static_cast<LauncherWidgets*>(user_data);
+    lv_obj_set_style_bg_color(parent, lv_color_hex(0x211A20), LV_PART_MAIN);
+    lv_obj_set_style_bg_opa(parent, LV_OPA_COVER, LV_PART_MAIN);
+    lv_obj_set_style_pad_all(parent, 0, LV_PART_MAIN);
+    lv_obj_clear_flag(parent, LV_OBJ_FLAG_SCROLLABLE);
+
+    auto* display = lv_obj_get_display(parent);
+    const auto display_width = lv_display_get_horizontal_resolution(display);
+    const auto display_height = lv_display_get_vertical_resolution(display);
+    const bool is_portrait = display_height > display_width;
+
+    auto background_path = lvgl::PATH_PREFIX + getDefaultBackgroundPath();
+    std::string sd_card_path;
+    if (findFirstMountedSdCardPath(sd_card_path)) {
+        const auto custom_background_path = file::getChildPath(sd_card_path, CUSTOM_BACKGROUND_PATH);
+        if (file::isFile(custom_background_path)) {
+            const auto lvgl_custom_background_path = lvgl::PATH_PREFIX + custom_background_path;
+            lv_image_header_t header {};
+            if (lv_image_decoder_get_info(lvgl_custom_background_path.c_str(), &header) == LV_RESULT_OK) {
+                if (header.w >= display_width && header.h >= display_height) {
+                    background_path = lvgl_custom_background_path;
+                    LOG_I(TAG, "Using SD background %s (%ux%u, format 0x%02x)",
+                        custom_background_path.c_str(), header.w, header.h, header.cf);
+                } else {
+                    LOG_W(TAG, "Ignoring undersized SD background %s (%ux%u for %dx%d display)",
+                        custom_background_path.c_str(), header.w, header.h, display_width, display_height);
+                }
+            } else {
+                LOG_W(TAG, "Ignoring invalid SD background %s", custom_background_path.c_str());
+            }
+        }
     }
 
-    const int32_t margin = is_landscape_display
-        ? computeButtonMargin(lv_display_get_horizontal_resolution(display), total_button_size)
-        : computeButtonMargin(lv_display_get_vertical_resolution(display), total_button_size);
+    auto* background = lv_image_create(parent);
+    lv_image_set_src(background, background_path.c_str());
+    lv_obj_align(background, LV_ALIGN_CENTER, 0, 0);
+    lv_obj_add_flag(background, LV_OBJ_FLAG_IGNORE_LAYOUT);
 
-    auto* app_list_button = createAppButton(buttons_wrapper, ui_density, LVGL_ICON_LAUNCHER_APPS, "tactility.applist", margin, is_landscape_display);
-    createAppButton(buttons_wrapper, ui_density, LVGL_ICON_LAUNCHER_FOLDER, "tactility.files", margin, is_landscape_display);
-    createAppButton(buttons_wrapper, ui_density, LVGL_ICON_LAUNCHER_SETTINGS, "tactility.settings", margin, is_landscape_display);
+    widgets.timeLabel = lv_label_create(parent);
+    lv_label_set_text(widgets.timeLabel, "--:--");
+    lv_obj_set_style_text_color(widgets.timeLabel, TEXT_COLOR, LV_PART_MAIN);
+#if LV_FONT_MONTSERRAT_48
+    lv_obj_set_style_text_font(widgets.timeLabel, &lv_font_montserrat_48, LV_PART_MAIN);
+#else
+    lv_obj_set_style_text_font(widgets.timeLabel, lvgl_get_text_font(FONT_SIZE_LARGE), LV_PART_MAIN);
+#endif
+    lv_obj_align(widgets.timeLabel, LV_ALIGN_TOP_LEFT, 18, 58);
 
-    // The launcher's container is several levels below the screen, and LVGL only sends
-    // LV_EVENT_SIZE_CHANGED to the screen object itself on a resolution change - so the
-    // handler is attached there, with buttons_wrapper passed through as user data.
-    lv_obj_add_event_cb(lv_obj_get_screen(parent), onButtonsWrapperResized, LV_EVENT_SIZE_CHANGED, buttons_wrapper);
-    lv_obj_add_event_cb(buttons_wrapper, onButtonsWrapperDeleted, LV_EVENT_DELETE, nullptr);
+    widgets.dateLabel = lv_label_create(parent);
+    lv_obj_set_style_text_font(widgets.dateLabel, lvgl_get_text_font(FONT_SIZE_LARGE), LV_PART_MAIN);
+    lv_obj_set_style_text_color(widgets.dateLabel, TEXT_COLOR, LV_PART_MAIN);
+    lv_obj_align(widgets.dateLabel, LV_ALIGN_TOP_LEFT, 20, 118);
+
+    widgets.dataLabel = lv_label_create(parent);
+    lv_obj_set_width(widgets.dataLabel, is_portrait ? display_width - 40 : 225);
+    lv_label_set_long_mode(widgets.dataLabel, LV_LABEL_LONG_MODE_WRAP);
+    lv_obj_set_style_text_font(widgets.dataLabel, lvgl_get_text_font(FONT_SIZE_SMALL), LV_PART_MAIN);
+    lv_obj_set_style_text_color(widgets.dataLabel, MUTED_TEXT_COLOR, LV_PART_MAIN);
+    lv_obj_align(widgets.dataLabel, LV_ALIGN_TOP_LEFT, 20, 148);
+
+    widgets.statusLabel = lv_label_create(parent);
+    lv_obj_set_style_text_font(widgets.statusLabel, lvgl_get_statusbar_icon_font(), LV_PART_MAIN);
+    lv_obj_set_style_text_color(widgets.statusLabel, TEXT_COLOR, LV_PART_MAIN);
+    lv_obj_align(widgets.statusLabel, LV_ALIGN_TOP_RIGHT, -15, 8);
+
+    auto* button_rail = lv_obj_create(parent);
+    if (is_portrait) {
+        lv_obj_set_size(button_rail, 184, 60);
+        lv_obj_align(button_rail, LV_ALIGN_BOTTOM_MID, 0, -7);
+        lv_obj_set_flex_flow(button_rail, LV_FLEX_FLOW_ROW);
+    } else {
+        lv_obj_set_size(button_rail, 60, 184);
+        lv_obj_align(button_rail, LV_ALIGN_RIGHT_MID, -7, 8);
+        lv_obj_set_flex_flow(button_rail, LV_FLEX_FLOW_COLUMN);
+    }
+    lv_obj_set_flex_align(button_rail, LV_FLEX_ALIGN_SPACE_EVENLY, LV_FLEX_ALIGN_CENTER, LV_FLEX_ALIGN_CENTER);
+    lv_obj_set_style_pad_all(button_rail, 0, LV_PART_MAIN);
+    lv_obj_set_style_border_width(button_rail, 0, LV_PART_MAIN);
+    lv_obj_set_style_bg_opa(button_rail, LV_OPA_TRANSP, LV_PART_MAIN);
+    lv_obj_clear_flag(button_rail, LV_OBJ_FLAG_SCROLLABLE);
+
+    auto* app_list_button = createAppButton(button_rail, LVGL_ICON_LAUNCHER_APPS, "tactility.applist", true);
+    createAppButton(button_rail, LVGL_ICON_LAUNCHER_FOLDER, "tactility.files", false);
+    createAppButton(button_rail, LVGL_ICON_LAUNCHER_SETTINGS, "tactility.settings", false);
 
-    // Some devices (e.g. T-Lora Pager) have no other way to power off, so the
-    // button stays in the launcher; the confirmation flow lives in the PowerOff app.
     if (shouldShowPowerButton()) {
         auto* power_button = lv_button_create(parent);
-        lv_obj_set_style_pad_all(power_button, 8, 0);
-        lv_obj_align(power_button, LV_ALIGN_BOTTOM_MID, 0, -10);
-        lv_obj_add_event_cb(power_button, onAppPressed, LV_EVENT_SHORT_CLICKED, (void*)"tactility.poweroff");
-        lv_obj_set_style_shadow_width(power_button, 0, LV_STATE_DEFAULT);
-        lv_obj_set_style_bg_opa(power_button, 0, LV_PART_MAIN);
-
+        lv_obj_set_size(power_button, 36, 36);
+        lv_obj_align(power_button, LV_ALIGN_BOTTOM_LEFT, 16, -12);
+        lv_obj_set_style_radius(power_button, LV_RADIUS_CIRCLE, LV_PART_MAIN);
+        lv_obj_set_style_shadow_width(power_button, 0, LV_PART_MAIN);
+        lv_obj_set_style_bg_color(power_button, lv_color_hex(0x211B20), LV_PART_MAIN);
+        lv_obj_set_style_bg_opa(power_button, LV_OPA_70, LV_PART_MAIN);
+        lv_obj_add_event_cb(power_button, onAppPressed, LV_EVENT_SHORT_CLICKED, const_cast<char*>("tactility.poweroff"));
         auto* power_label = lv_label_create(power_button);
         lv_label_set_text(power_label, LV_SYMBOL_POWER);
-        lv_obj_set_style_text_color(power_label, lv_theme_get_color_primary(parent), LV_STATE_DEFAULT);
+        lv_obj_set_style_text_color(power_label, TEXT_COLOR, LV_PART_MAIN);
+        lv_obj_center(power_label);
     }
 
-    // If we don't have a touch device, we assume there's some other kind of input like a keyboard, an encoder or button control
-    // In that scenario we want to automatically have the app list button selected so the user doesn't have to press the widget selection
-    // an extra time.
     if (!device_has_active_by_type(&POINTER_TYPE)) {
-        // lv_obj_update_layout(parent); // Resolve flex layout first, so focus/state invalidate against final coords
         lv_group_focus_obj(app_list_button);
         lv_obj_add_state(app_list_button, LV_STATE_FOCUS_KEY);
     }
+
+    updateInformation(widgets);
+    widgets.updateTimer = lv_timer_create(onUpdateTimer, 1000, &widgets);
+}
+
+void destroyWidgets(void* user_data) {
+    auto& widgets = *static_cast<LauncherWidgets*>(user_data);
+    if (widgets.updateTimer != nullptr) {
+        lv_timer_delete(widgets.updateTimer);
+        widgets.updateTimer = nullptr;
+    }
+    widgets.timeLabel = nullptr;
+    widgets.dateLabel = nullptr;
+    widgets.dataLabel = nullptr;
+    widgets.statusLabel = nullptr;
 }
 
 void runAutoStart() {
     settings::BootSettings boot_properties;
     AppManifest manifest;
-    if (
-        // Auto-start due to built-in requirement
-        strcmp(CONFIG_TT_AUTO_START_APP_ID, "") != 0 &&
-        app_manager_find_manifest(CONFIG_TT_AUTO_START_APP_ID, &manifest) == ERROR_NONE
-    ) {
+    if (strcmp(CONFIG_TT_AUTO_START_APP_ID, "") != 0 &&
+        app_manager_find_manifest(CONFIG_TT_AUTO_START_APP_ID, &manifest) == ERROR_NONE) {
         LOG_I(TAG, "Starting %s", CONFIG_TT_AUTO_START_APP_ID);
         uint32_t app_launch_id;
         app_start(CONFIG_TT_AUTO_START_APP_ID, 0, nullptr, &app_launch_id);
-    } else if (
-        // Auto-start due to user configuration
-        settings::loadBootSettings(boot_properties) &&
-        !boot_properties.autoStartAppId.empty() &&
-        app_manager_find_manifest(boot_properties.autoStartAppId.c_str(), &manifest) == ERROR_NONE
-    ) {
+    } else if (settings::loadBootSettings(boot_properties) &&
+               !boot_properties.autoStartAppId.empty() &&
+               app_manager_find_manifest(boot_properties.autoStartAppId.c_str(), &manifest) == ERROR_NONE) {
         LOG_I(TAG, "Starting %s", boot_properties.autoStartAppId.c_str());
         uint32_t app_launch_id;
         app_start(boot_properties.autoStartAppId.c_str(), 0, nullptr, &app_launch_id);
-    } else {
-        // No auto-start, consider running system setup
-        if (!setup::isCompleted()) {
-            setup::start();
-        }
+    } else if (!setup::isCompleted()) {
+        setup::start();
     }
 }
 
 int32_t appMain(int argc, char* argv[]) {
-    uint32_t appInstanceId = app_scheduler_current_app_id();
+    uint32_t app_instance_id = app_scheduler_current_app_id();
     runAutoStart();
 
+    LauncherWidgets widgets;
+    WindowId window = window_manager_create_ext(app_instance_id, createWidgets, destroyWidgets, &widgets);
+
     TaskEventGroup event_group {};
     task_event_group_construct(&event_group);
-
     AppEventSubscription sub {};
     check(app_event_subscribe(&sub, &event_group) == ERROR_NONE);
 
-    WindowId window = window_manager_create(appInstanceId, createWidgets, nullptr);
-
-    // The launcher is meant to stay resident (it's the home screen) - it only gives up its
-    // thread when app-module's scheduler asks it to (e.g. another new-model app is started).
     while (true) {
         task_event_group_wait_any(&event_group, nullptr, portMAX_DELAY);
-
-        bool shouldClose = false;
+        bool should_close = false;
         AppEvent event {};
         while (app_event_poll(&sub, &event) == ERROR_NONE) {
             if (event.type == APP_EVENT_CLOSE) {
-                shouldClose = true;
+                should_close = true;
                 break;
             }
         }
-        if (shouldClose) break;
+        if (should_close) break;
     }
 
     window_manager_remove(window);
@@ -275,16 +363,13 @@ extern const ::AppManifest manifest = {
     .category = APP_CATEGORY_SYSTEM,
     .location = { .type = APP_LOCATION_MEMORY, .location = reinterpret_cast<void*>(appMain) },
     .flags = APP_MANIFEST_FLAG_HIDDEN,
-    // No file IO, so callstack can be in external RAM
-    .stack = { .depth = 3072 , .desired_memory_capability = MEMORY_CAPABILITY_EXTERNAL }
+    .stack = { .depth = 3072, .desired_memory_capability = MEMORY_CAPABILITY_EXTERNAL }
 };
 
-// Kept for Tactility/Private/Tactility/app/launcher/Launcher.h's existing declaration (still
-// used by the old, unconverted CrashDiagnostics app to return to the launcher after a crash).
 uint32_t start() {
     uint32_t instance_id = 0;
     app_start(manifest.id, 0, nullptr, &instance_id);
     return instance_id;
 }
 
-} // namespace
+} // namespace tt::app::launcher

Tactility/Source/app/localesettings/LocaleSettings.cpp

@@ -182,7 +182,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.localesettings",
     .name = "Region & Language",
     .category = APP_CATEGORY_SETTINGS,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace tt::app::localesettings

Tactility/Source/app/mcpsettings/McpSettingsApp.cpp

@@ -0,0 +1,97 @@
+#ifdef ESP_PLATFORM
+#include <Tactility/Tactility.h>
+#include <Tactility/lvgl/Lvgl.h>
+#include <Tactility/settings/McpSettings.h>
+#include <Tactility/settings/WebServerSettings.h>
+#include <Tactility/service/webserver/WebServerService.h>
+#include <app/event.h>
+#include <app/manifest.h>
+#include <app/scheduler.h>
+#include <lvgl_window_manager/window_manager.h>
+#include <lvgl/widgets/toolbar.h>
+#include <lvgl/lvgl.h>
+#include <tactility/check.h>
+#include <tactility/log.h>
+#include <esp_netif.h>
+
+#include <string>
+
+namespace tt::app::mcpsettings {
+constexpr auto* TAG = "McpSettingsApp";
+extern const ::AppManifest manifest;
+namespace {
+struct Context {
+    uint32_t appInstanceId;
+    settings::mcp::McpSettings mcpSettings;
+    settings::webserver::WebServerSettings wsSettings;
+    lv_obj_t* switchMcpEnabled = nullptr;
+    lv_obj_t* labelUrlValue = nullptr;
+};
+
+void updateUrlDisplay(Context* ctx) {
+    if (ctx->labelUrlValue == nullptr) return;
+    if (!ctx->mcpSettings.mcpEnabled) { lv_label_set_text(ctx->labelUrlValue, "Disabled"); return; }
+    std::string url = "http://";
+    bool ipAdded = false;
+    for (const char* key : {"WIFI_STA_DEF", "WIFI_AP_DEF"}) {
+        auto* netif = esp_netif_get_handle_from_ifkey(key);
+        if (netif != nullptr) {
+            esp_netif_ip_info_t info;
+            if (esp_netif_get_ip_info(netif, &info) == ESP_OK && info.ip.addr != 0) {
+                char ip[16]; snprintf(ip, sizeof(ip), IPSTR, IP2STR(&info.ip));
+                url += ip; ipAdded = true; break;
+            }
+        }
+    }
+    if (!ipAdded) url += ctx->wsSettings.wifiMode == settings::webserver::WiFiMode::AccessPoint ? "192.168.4.1" : "Connecting...";
+    if (url.starts_with("http://") && ctx->wsSettings.webServerPort != 80) url += ":" + std::to_string(ctx->wsSettings.webServerPort);
+    url += "/api/mcp";
+    lv_label_set_text(ctx->labelUrlValue, url.c_str());
+}
+
+void onBackPressed(lv_event_t* event) {
+    auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
+    app_event_emit_close(ctx->appInstanceId);
+}
+
+void onMcpEnabledSwitch(lv_event_t* event) {
+    auto* ctx = static_cast<Context*>(lv_event_get_user_data(event));
+    const bool enabled = lv_obj_has_state(ctx->switchMcpEnabled, LV_STATE_CHECKED);
+    getMainDispatcher().dispatch([ctx, enabled] {
+        ctx->mcpSettings.mcpEnabled = enabled;
+        lvgl_lock(); updateUrlDisplay(ctx); lvgl_unlock();
+        if (!settings::mcp::save(ctx->mcpSettings)) LOG_W(TAG, "Failed to persist MCP settings");
+        service::webserver::getPubsub()->publish(service::webserver::WebServerEvent::WebServerSettingsChanged);
+        service::webserver::setWebServerEnabled(enabled);
+    });
+}
+
+void createWidgets(lv_obj_t* parent, void* userData) {
+    auto* ctx = static_cast<Context*>(userData);
+    ctx->wsSettings = settings::webserver::loadOrGetDefault();
+    lv_obj_set_flex_flow(parent, LV_FLEX_FLOW_COLUMN);
+    lv_obj_set_style_pad_row(parent, 0, LV_STATE_DEFAULT);
+    auto* toolbar = lvgl_toolbar_create(parent, "MCP Settings");
+    lvgl_toolbar_set_nav_action(toolbar, LV_SYMBOL_CLOSE, onBackPressed, ctx);
+    ctx->switchMcpEnabled = lvgl_toolbar_add_switch_action(toolbar);
+    if (ctx->mcpSettings.mcpEnabled) lv_obj_add_state(ctx->switchMcpEnabled, LV_STATE_CHECKED);
+    lv_obj_add_event_cb(ctx->switchMcpEnabled, onMcpEnabledSwitch, LV_EVENT_VALUE_CHANGED, ctx);
+    auto* main = lv_obj_create(parent); lv_obj_set_flex_flow(main, LV_FLEX_FLOW_COLUMN); lv_obj_set_width(main, LV_PCT(100)); lv_obj_set_flex_grow(main, 1);
+    auto* wrapper = lv_obj_create(main); lv_obj_set_size(wrapper, LV_PCT(100), LV_SIZE_CONTENT); lv_obj_set_style_pad_all(wrapper, 10, LV_STATE_DEFAULT); lv_obj_set_style_border_width(wrapper, 1, LV_STATE_DEFAULT); lv_obj_set_flex_flow(wrapper, LV_FLEX_FLOW_COLUMN); lv_obj_set_style_flex_cross_place(wrapper, LV_FLEX_ALIGN_START, 0);
+    auto* title = lv_label_create(wrapper); lv_label_set_text(title, "MCP Endpoint URL:");
+    ctx->labelUrlValue = lv_label_create(wrapper); updateUrlDisplay(ctx);
+    auto* info = lv_label_create(main); lv_label_set_long_mode(info, LV_LABEL_LONG_WRAP); lv_obj_set_width(info, LV_PCT(95));
+    lv_label_set_text(info, "MCP (Model Context Protocol) Screen service allows LLMs to interact with the device screen, audio, and tools directly.\n\nEndpoints:\n- POST /api/mcp (JSON-RPC tools)\n- POST /api/screen/raw (big-endian RGB565 writes)\n\nTo show the LLM canvas, select 'MCP Screen' in Settings -> Display -> Screensaver. The canvas also pops up automatically when an LLM sends a draw command.");
+}
+
+int32_t appMain(int, char**) {
+    Context ctx{}; ctx.appInstanceId = app_scheduler_current_app_id(); ctx.mcpSettings = settings::mcp::loadOrGetDefault();
+    TaskEventGroup group{}; task_event_group_construct(&group); AppEventSubscription sub{}; check(app_event_subscribe(&sub, &group) == ERROR_NONE);
+    auto window = window_manager_create(ctx.appInstanceId, createWidgets, &ctx); bool close = false;
+    while (!close) { task_event_group_wait_any(&group, nullptr, portMAX_DELAY); AppEvent event{}; while (app_event_poll(&sub, &event) == ERROR_NONE) if (event.type == APP_EVENT_CLOSE) { close = true; break; } }
+    window_manager_remove(window); check(app_event_unsubscribe(&sub) == ERROR_NONE); task_event_group_destruct(&group); return 0;
+}
+}
+extern const ::AppManifest manifest = { .id = "McpSettings", .name = "MCP Screen", .category = APP_CATEGORY_SETTINGS, .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }, .flags = APP_MANIFEST_FLAG_HIDDEN, .stack = { .depth = 8192, .desired_memory_capability = 0 } };
+}
+#endif

Tactility/Source/app/mcpsettings/McpSettingsSimulatorApp.cpp

@@ -0,0 +1,66 @@
+#ifndef ESP_PLATFORM
+
+#include <app/event.h>
+#include <app/manifest.h>
+#include <app/scheduler.h>
+#include <lvgl/lvgl.h>
+#include <lvgl_window_manager/window_manager.h>
+
+namespace tt::app::mcpsettings {
+struct Context { AppInstanceId instanceId; };
+
+void createMcpInfo(lv_obj_t* parent, void* userData) {
+    auto* context = static_cast<Context*>(userData);
+    lv_obj_t* title = lv_label_create(parent);
+    lv_label_set_text(title, "MCP Settings");
+    lv_obj_align(title, LV_ALIGN_TOP_MID, 0, 18);
+
+    lv_obj_t* info = lv_label_create(parent);
+    lv_label_set_text(info,
+        "MCP is available while the simulator web server is running.\n\n"
+        "Endpoint: POST /api/mcp\n"
+        "JSON-RPC methods: tools/list, tools/call\n\n"
+        "Simulator tools: get_capabilities, clear_screen, draw_text, list_apps, run_app\n\n"
+        "Open the simulator dashboard/API at http://127.0.0.1/api/sysinfo.");
+    lv_label_set_long_mode(info, LV_LABEL_LONG_WRAP);
+    lv_obj_set_width(info, LV_PCT(90));
+    lv_obj_align(info, LV_ALIGN_CENTER, 0, 8);
+
+    (void)context;
+}
+
+int32_t appMain(int, char**) {
+    Context context{app_scheduler_current_app_id()};
+    TaskEventGroup group{};
+    task_event_group_construct(&group);
+    AppEventSubscription subscription{};
+    if (app_event_subscribe(&subscription, &group) != ERROR_NONE) {
+        task_event_group_destruct(&group);
+        return -1;
+    }
+    auto window = window_manager_create(context.instanceId, createMcpInfo, &context);
+    bool close = false;
+    while (!close) {
+        task_event_group_wait_any(&group, nullptr, portMAX_DELAY);
+        AppEvent event{};
+        while (app_event_poll(&subscription, &event) == ERROR_NONE) {
+            if (event.type == APP_EVENT_CLOSE) { close = true; break; }
+        }
+    }
+    window_manager_remove(window);
+    app_event_unsubscribe(&subscription);
+    task_event_group_destruct(&group);
+    return 0;
+}
+
+extern const AppManifest manifest = {
+    .id = "McpSettings",
+    .name = "MCP Settings",
+    .category = APP_CATEGORY_SETTINGS,
+    .location = {APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain)},
+    .flags = 0,
+    .stack = {.depth = 8192, .desired_memory_capability = 0}
+};
+}
+
+#endif

Tactility/Source/app/notes/Notes.cpp

@@ -276,7 +276,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.notes",
     .name = "Notes",
     .category = APP_CATEGORY_USER,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace tt::app::notes

Tactility/Source/app/power/Power.cpp

@@ -278,7 +278,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.power",
     .name = "Power",
     .category = APP_CATEGORY_SETTINGS,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace

Tactility/Source/app/screenshot/Screenshot.cpp

@@ -290,7 +290,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.screenshot",
     .name = "Screenshot",
     .category = APP_CATEGORY_SYSTEM,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace

Tactility/Source/app/settings/Settings.cpp

@@ -118,7 +118,7 @@ extern const ::AppManifest manifest = {
     .category = APP_CATEGORY_SYSTEM,
     .location = { .type = APP_LOCATION_MEMORY, .location = reinterpret_cast<void*>(appMain) },
     .flags = APP_MANIFEST_FLAG_HIDDEN,
-    .stack = { .depth = 2400, .desired_memory_capability = 0 },
+    .stack = { .depth = 3072, .desired_memory_capability = 0 },
 };
 
 } // namespace

Tactility/Source/app/systeminfo/SystemInfo.cpp

@@ -457,7 +457,8 @@ extern const ::AppManifest manifest = {
     .id = "tactility.systeminfo",
     .name = "System Info",
     .category = APP_CATEGORY_SYSTEM,
-    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) }
+    .location = { APP_LOCATION_MEMORY, reinterpret_cast<void*>(appMain) },
+    .flags = APP_MANIFEST_FLAG_HIDDEN
 };
 
 } // namespace