diff --git a/README.md b/README.md
index df6fe44..d476776 100644
--- a/README.md
+++ b/README.md
@@ -41,3 +41,5 @@ Note it only works with the Raspberry Pi 3B+
 2025 Marc Monka
 
 2026 Markus Golec
+
+2026 Jeancarlo Cardoso de Faria Filho (jaianlab) — Raspberry Pi Pico port, MCP developer tool
diff --git a/tools/README.md b/tools/README.md
new file mode 100644
index 0000000..876fdbd
--- /dev/null
+++ b/tools/README.md
@@ -0,0 +1,165 @@
+# XDJ-100SX Developer Tool
+
+Claude Code MCP server + CLI + TUI for the XDJ-100SX Pi system.
+Push skin files, take screenshots, flash firmware, and manage the Pi — all from your editor.
+
+---
+
+## Requirements
+
+```bash
+pip install paramiko watchdog textual
+```
+
+---
+
+## Quick start
+
+```bash
+python3 tools/xdj-pi-dev.py --check      # verify connection + environment
+python3 tools/xdj-pi-dev.py --status     # live Pi + Mixxx status
+python3 tools/xdj-pi-dev.py --ui         # interactive TUI
+python3 tools/xdj-pi-dev.py --about      # authors & credits
+python3 tools/xdj-pi-dev.py --help       # full command reference
+```
+
+---
+
+## Connection
+
+The tool tries these in order:
+
+1. `--host` flag
+2. `XDJ_HOST` environment variable
+3. `XDJ100SX.local` — mDNS, works on any network (WiFi or LAN)
+4. `192.168.10.2` — static IP fallback for direct cable
+
+### Direct cable (no router)
+
+One-time setup on your machine:
+
+```bash
+# macOS
+sudo ifconfig en0 alias 192.168.10.1 255.255.255.0
+
+# Linux
+sudo ip addr add 192.168.10.1/24 dev eth0
+
+# Windows (run as Administrator)
+netsh interface ip set address "Ethernet" static 192.168.10.1 255.255.255.0
+```
+
+Then on the Pi (once):
+
+```bash
+python3 tools/xdj-pi-dev.py --setup-pi-dhcp
+```
+
+After that the Pi hands out IPs automatically — no manual config needed on any machine.
+
+### Multi-unit
+
+Each Pi should have a unique hostname:
+
+```bash
+python3 tools/xdj-pi-dev.py --set-hostname xdj-unit2
+```
+
+Then from Claude Code:
+- `discover_units` — lists all reachable XDJ units on the network
+- `select_unit` — switches the active connection to a specific unit
+
+---
+
+## Claude Code MCP setup
+
+Add to `.mcp.json` in your project root:
+
+```json
+{
+  "mcpServers": {
+    "xdj-pi-dev": {
+      "command": "python3",
+      "args": ["tools/xdj-pi-dev.py"]
+    }
+  }
+}
+```
+
+Add to `.claude/settings.local.json`:
+
+```json
+{
+  "enabledMcpjsonServers": ["xdj-pi-dev"]
+}
+```
+
+Restart Claude Code. Once connected, you can say things like:
+
+- *"push the skin and take a screenshot"*
+- *"change the play button color in style.qss, push and screenshot"*
+- *"restart Mixxx and navigate to the beat loop panel"*
+- *"flash the firmware"*
+- *"find all XDJ units on the network"*
+
+---
+
+## CLI reference
+
+### Setup
+
+```bash
+--check                  # preflight: deps, SSH, Mixxx, audio, Pico
+--discover               # scan network for all Pi units
+--setup-pi-dhcp          # configure Pi as DHCP server on eth0
+--setup-ssh-keys         # passwordless SSH (recommended)
+--set-hostname NAME      # rename Pi (e.g. xdj-unit2)
+--backup-image           # backup SD card to .tar archive
+--restore-ssh            # recovery guide if SSH is locked out
+```
+
+### Skin development
+
+```bash
+--push                   # push all skin files to Pi
+--push "*.qss"           # push only matching files
+--pull                   # pull skin files from Pi to repo
+--screenshot             # capture Pi display
+--screenshot --panel ks  # navigate to panel first (hc/bl/bj/ks/st)
+--restart                # restart Mixxx
+--watch                  # watch, auto-push + screenshot on save
+--watch --panel hc       # watch with panel navigation
+```
+
+### MIDI
+
+```bash
+--push-midi              # push MIDI mapping to Pi
+--pull-midi              # pull MIDI mapping from Pi
+--midi-mon               # stream live MIDI messages (Ctrl-C to stop)
+```
+
+### Pico firmware
+
+```bash
+--setup-pico-cli         # install arduino-cli on Pi (one-time)
+--pico-compile           # compile firmware on Pi
+--pico-bootloader        # reset Pico to UF2 bootloader
+--pico-flash FILE.uf2    # flash a local .uf2 to Pi
+--analyze                # live GPIO signal analyzer
+```
+
+### Other
+
+```bash
+--cmd 'CMD'              # run arbitrary SSH command on Pi
+--host 192.168.1.42      # target a specific IP or hostname
+--ui                     # open interactive TUI (requires textual)
+--about                  # show authors and credits
+```
+
+---
+
+## Skin development guide
+
+See [`SKIN_DEV.md`](SKIN_DEV.md) for Mixxx widget types, layout rules, ConfigKeys, QSS constraints, and color palette — everything Claude needs to build and modify skin files correctly.
diff --git a/tools/SKIN_DEV.md b/tools/SKIN_DEV.md
new file mode 100644
index 0000000..963a102
--- /dev/null
+++ b/tools/SKIN_DEV.md
@@ -0,0 +1,358 @@
+# XDJ-100SX Skin Development Guide
+
+Context for Claude Code (via MCP) and human contributors working on the Mixxx skin.
+
+---
+
+## Overview
+
+The skin runs on a **Raspberry Pi** connected to a **480×272 touchscreen** (landscape).
+Mixxx renders the skin as a single-deck player — no second deck, no samplers, no vinyl control.
+
+The skin files live in `mixxx/SKIN/XDJ100SX/`. Push changes with:
+
+```bash
+python3 tools/xdj-pi-dev.py --push        # push all files
+python3 tools/xdj-pi-dev.py --push "*.qss" # push only QSS
+python3 tools/xdj-pi-dev.py --screenshot   # see the result
+```
+
+Or use `--watch` to auto-push and screenshot on every save.
+
+---
+
+## File Structure
+
+| File | Purpose |
+|------|---------|
+| `skin.xml` | Root — loads style.qss, sets minimum size, defines launch image |
+| `config.xml` | Top-level layout: Day/Night toggle + deck area |
+| `deck.xml` | Main deck template — info row, waveform, transport, performance panels |
+| `deckminimal.xml` | Minimal deck view (collapsed state) |
+| `tab.xml` | Reusable tab button template |
+| `topbar.xml` | Top bar — BPM, pitch, track info |
+| `waveform.xml` / `waveforms.xml` | Waveform display widgets |
+| `overview.xml` | Track overview / position bar |
+| `hotcues.xml` | Hot cue performance panel |
+| `beatloop.xml` | Beat loop performance panel |
+| `beatjump.xml` | Beat jump performance panel |
+| `keyshift.xml` | Key shift performance panel |
+| `stems.xml` | Stems performance panel |
+| `beffect.xml` / `ceffectl.xml` / `ceffectr.xml` | Effect panels |
+| `effects.xml` | Effects rack |
+| `library.xml` | Library browser panel |
+| `style.qss` | All QSS styling |
+
+---
+
+## Layout System
+
+### Size syntax
+
+```xml
+<Size>WIDTH,HEIGHT</Size>
+```
+
+Suffixes:
+- `f` — fixed (exact pixels, no stretch)
+- `me` — minimum, expands
+- `max` — maximum (won't grow beyond this)
+- `min` — minimum (won't shrink below this)
+- No suffix — exact fixed size
+
+Examples:
+```xml
+<Size>65f,40f</Size>      <!-- 65×40, fixed -->
+<Size>0me,65max</Size>    <!-- expands horizontally, max 65px tall -->
+<Size>me,me</Size>        <!-- fills available space -->
+```
+
+### SizePolicy
+
+```xml
+<SizePolicy>me,me</SizePolicy>   <!-- preferred grow behavior -->
+<SizePolicy>f,f</SizePolicy>     <!-- fixed -->
+```
+
+### Layout
+
+```xml
+<Layout>vertical</Layout>
+<Layout>horizontal</Layout>
+```
+
+### WidgetStack
+
+Shows one child at a time based on a ConfigKey value. Used for the performance panel tabs (hotcues, beatloop, etc.):
+
+```xml
+<WidgetStack>
+  <Children>
+    <WidgetGroup>...</WidgetGroup>  <!-- shown when stack index = 0 -->
+    <WidgetGroup>...</WidgetGroup>  <!-- shown when stack index = 1 -->
+  </Children>
+</WidgetStack>
+```
+
+### Templates
+
+Reusable XML fragments with variables:
+
+```xml
+<!-- Definition (tab.xml) -->
+<Template>
+  <PushButton>
+    <ObjectName>TabButton<Variable name="tab_name"/></ObjectName>
+    <Connection>
+      <ConfigKey>[Tab],<Variable name="config_key"/></ConfigKey>
+    </Connection>
+  </PushButton>
+</Template>
+
+<!-- Usage -->
+<Template src="skin:tab.xml">
+  <SetVariable name="tab_name">HOT CUE</SetVariable>
+  <SetVariable name="config_key">hotcue</SetVariable>
+</Template>
+```
+
+---
+
+## Widget Types
+
+### PushButton
+
+```xml
+<PushButton>
+  <ObjectName>MyButton</ObjectName>
+  <Size>65f,40f</Size>
+  <NumberStates>2</NumberStates>
+  <State>
+    <Number>0</Number>
+    <Text>OFF</Text>
+    <!-- <Pixmap>skin:/images/btn_off.png</Pixmap> -->
+  </State>
+  <State>
+    <Number>1</Number>
+    <Text>ON</Text>
+  </State>
+  <Connection>
+    <ConfigKey>[Channel1],play</ConfigKey>
+  </Connection>
+</PushButton>
+```
+
+### Label
+
+```xml
+<Label>
+  <ObjectName>TrackTitle</ObjectName>
+  <Size>me,20f</Size>
+  <Text>No Track</Text>
+  <Connection>
+    <ConfigKey>[Channel1],title</ConfigKey>
+    <BindProperty>text</BindProperty>
+  </Connection>
+</Label>
+```
+
+### NumberLabel / NumberDisplay
+
+For numeric values (BPM, pitch, time):
+
+```xml
+<NumberLabel>
+  <ObjectName>BPM</ObjectName>
+  <Size>60f,25f</Size>
+  <Connection>
+    <ConfigKey>[Channel1],bpm</ConfigKey>
+  </Connection>
+</NumberLabel>
+```
+
+### WaveformDisplay
+
+```xml
+<Visual>
+  <ObjectName>Waveform</ObjectName>
+  <Size>me,80f</Size>
+  <Channel>1</Channel>
+  <BgColor>#000</BgColor>
+  <BgPixmap></BgPixmap>
+  <EndOfTrackColor>#ff4444</EndOfTrackColor>
+</Visual>
+```
+
+### Overview (track position bar)
+
+```xml
+<Overview>
+  <ObjectName>TrackOverview</ObjectName>
+  <Size>me,30f</Size>
+  <Channel>1</Channel>
+  <BgColor>#111</BgColor>
+  <EndOfTrackColor>#ff0000</EndOfTrackColor>
+</Overview>
+```
+
+### WidgetGroup (container)
+
+```xml
+<WidgetGroup>
+  <ObjectName>MyGroup</ObjectName>
+  <Layout>horizontal</Layout>
+  <Size>me,40f</Size>
+  <Children>
+    <!-- child widgets here -->
+  </Children>
+</WidgetGroup>
+```
+
+---
+
+## ConfigKeys
+
+Format: `[Group],control`
+
+### Deck controls (single deck — always Channel1)
+
+| ConfigKey | Description |
+|-----------|-------------|
+| `[Channel1],play` | Play/pause toggle |
+| `[Channel1],cue_default` | Cue button |
+| `[Channel1],bpm` | Current BPM |
+| `[Channel1],rate` | Pitch/rate slider |
+| `[Channel1],volume` | Channel volume |
+| `[Channel1],quantize` | Quantize on/off |
+| `[Channel1],keylock` | Key lock on/off |
+| `[Channel1],sync_enabled` | Sync on/off |
+| `[Channel1],loop_enabled` | Loop active |
+| `[Channel1],beatloop_size` | Current loop size |
+| `[Channel1],hotcue_X_activate` | Trigger hot cue X |
+| `[Channel1],hotcue_X_clear` | Clear hot cue X |
+| `[Channel1],title` | Track title (text) |
+| `[Channel1],artist` | Track artist (text) |
+| `[Channel1],track_loaded` | 1 if track is loaded |
+
+### Tab/panel switching (skin-internal)
+
+The performance panels are driven by `[Channel2]` filter kill controls repurposed as tab flags — this is a hack to use existing bool ConfigKeys for panel visibility without needing Mixxx scripting:
+
+```xml
+<!-- Show hotcue panel when this is 1 -->
+<Connection>
+  <ConfigKey>[Channel2],filterLowKill</ConfigKey>
+  <BindProperty>visible</BindProperty>
+</Connection>
+```
+
+**Do not change this pattern** — it would require updating both skin XML and the MIDI mapping script.
+
+### Skin-internal toggles
+
+```xml
+[Skin],daynight_toggle   <!-- Day/Night mode switch -->
+```
+
+---
+
+## QSS Styling
+
+Standard Qt stylesheet — subset of CSS. Applied via `style.qss`.
+
+### What works
+
+- `background-color`, `color`, `border`, `border-radius`
+- `font-family`, `font-size`, `font-weight`
+- `padding`, `margin`
+- `min-width`, `max-width`, `min-height`, `max-height`
+- `image: url(skin:/images/file.png)` — skin-relative paths
+- State selectors: `WPushButton[value="1"]` — styling when button is active
+
+### What does NOT work
+
+- CSS Grid, Flexbox — not Qt
+- CSS variables (`--my-var`) — not supported
+- Animations / transitions
+- `::before` / `::after` pseudo-elements
+- `url()` with absolute paths — always use `skin:/` prefix for images
+- `rgba()` with 4 args sometimes fails — test on device
+
+### Object name targeting
+
+```css
+#MyButton { background: #333; }           /* by ObjectName */
+WPushButton { border: 1px solid white; }  /* by widget type */
+WPushButton[value="1"] { color: red; }    /* active state */
+```
+
+### Color palette (Pioneer style)
+
+```
+Play green:    #6ee128
+Cue orange:    #eb870f
+Slip red:      #d73535
+Tab yellow:    #c3d541
+Header dark:   #32323c
+Title blue bg: #112f5c
+Blue accent:   #2d85cd
+Text white:    #e5e6ea
+Background:    #000000
+```
+
+---
+
+## Constraints & Rules
+
+### Screen
+
+- **Physical display**: 480×272px
+- **Skin minimum**: 480×420 (Mixxx scales to fit, Pi display is rotated/scaled)
+- Keep UI elements large enough to be finger-tappable (minimum ~40px touch targets)
+- No horizontal scrolling — everything must fit in 480px width
+
+### Single deck only
+
+- Always use `[Channel1]` — never `[Channel2]`, `[Channel3]`, `[Channel4]` for actual controls
+- `[Channel2]` filter kills are repurposed as panel tab visibility flags — don't use them for audio
+
+### Performance panels
+
+The skin has 5 performance panels (tabs): Hot Cue, Beat Loop, Beat Jump, Key Shift, Stems.
+They are mutually exclusive (WidgetStack). Do not add a 6th tab without updating:
+- The tab button row in `deck.xml`
+- The WidgetStack in `deck.xml`
+- The MIDI mapping in `XDJ100SX.midi.xml` and `XDJ100SX.js`
+
+### Images
+
+- Place in `mixxx/SKIN/XDJ100SX/images/`
+- Reference as `skin:/images/filename.png`
+- Keep image sizes minimal — Pi SD card and RAM are limited
+- PNG preferred; avoid large JPEGs
+
+### Templates
+
+- Template files must start with `<Template>` as root element
+- Variables are set with `<SetVariable name="...">value</SetVariable>`
+- Used at call site with `<Template src="skin:file.xml">`
+
+---
+
+## Workflow with Claude Code MCP
+
+When connected via MCP, Claude can:
+
+```
+"push the skin and take a screenshot"
+"change the play button color to green in style.qss, push and screenshot"
+"push only the hotcues.xml file"
+"restart Mixxx then screenshot the beat loop panel"
+"navigate to keyshift panel and screenshot"
+```
+
+Claude cannot:
+- Modify Mixxx source code
+- Change MIDI hardware behavior without updating both `.midi.xml` and `.js`
+- Add new Mixxx controls that don't exist in the running Mixxx version
+- Test interaction — only static screenshots are available via MCP
diff --git a/tools/xdj-pi-dev.py b/tools/xdj-pi-dev.py
new file mode 100644
index 0000000..7e354dd
--- /dev/null
+++ b/tools/xdj-pi-dev.py
@@ -0,0 +1,2540 @@
+#!/usr/bin/env python3
+"""
+XDJ-100SX Pi Developer Tool  v3
+=================================
+CLI developer tool + MCP server for Claude Code.
+Works on macOS, Linux, and Windows.
+
+AUTHORS
+-------
+  Marc Monka <marc.monka@gmail.com>
+      Creator of the XDJ-100SX — original concept, firmware, Mixxx skin, and
+      hardware adaptation of the Pioneer DJ CDJ-100S. Uses the original CDJ-100S
+      PCB with added microcontroller (Teensy) to interface controls with a
+      Raspberry Pi running Mixxx.
+      https://github.com/marcmonka
+
+  Jeancarlo Cardoso de Faria Filho (jaianlab) <jaianlabworks@gmail.com>
+      Raspberry Pi Pico port (replacing Teensy), MCP server, multi-unit
+      discovery, developer tooling, and Pi setup automation.
+      https://github.com/jaianlab
+
+CREDITS & NOTICES
+-----------------
+  Mixxx  <https://mixxx.org>
+      Free, open-source DJ software powering the XDJ-100SX skin and MIDI
+      mapping on the Pi. Mixxx is a project of the Mixxx Development Team
+      and contributors, licensed under GPLv2+. This tool interacts with
+      Mixxx but is not part of the Mixxx project.
+
+  Pioneer DJ
+      The CDJ-100S enclosure and PCB used in this project are products of
+      Pioneer DJ Co., Ltd. The XDJ-100SX is an independent community project
+      and is not affiliated with, endorsed by, or sponsored by Pioneer DJ.
+      All Pioneer DJ trademarks and product names belong to their respective owners.
+
+  Raspberry Pi
+      Pi hardware and software trademarks are the property of Raspberry Pi Ltd.
+      This tool targets Raspberry Pi hardware but is not affiliated with
+      Raspberry Pi Ltd.
+
+FIRST RUN:
+  python3 xdj-pi-dev.py --check           # diagnose connection + environment
+  python3 xdj-pi-dev.py --status          # Pi + Mixxx live status
+
+CONNECTION (tried in order):
+  1. --host flag
+  2. XDJ_HOST environment variable
+  3. XDJ100SX.local  (mDNS — works with any network topology)
+  4. 192.168.10.2    (static IP fallback)
+
+  Direct cable — one-time client setup:
+    macOS:    sudo ifconfig en0 alias 192.168.10.1 255.255.255.0
+    Linux:    sudo ip addr add 192.168.10.1/24 dev eth0
+    Windows:  netsh interface ip set address "Ethernet" static 192.168.10.1 255.255.255.0
+
+  Or run --setup-pi-dhcp once (on Pi) so the client gets an IP automatically —
+  no manual configuration needed after that.
+
+SETUP COMMANDS:
+  python3 xdj-pi-dev.py --check                   # pre-flight: deps, connection, Mixxx
+  python3 xdj-pi-dev.py --setup-pi-dhcp           # configure Pi to auto-assign IPs (do once)
+  python3 xdj-pi-dev.py --setup-ssh-keys          # set up key-based SSH auth (more secure)
+  python3 xdj-pi-dev.py --set-hostname NAME       # rename Pi (e.g. xdj-unit2 for multi-unit)
+  python3 xdj-pi-dev.py --backup-image            # backup SD card to .tar archive (used blocks only)
+  python3 xdj-pi-dev.py --backup-image backup.tar # backup to a specific path
+  python3 xdj-pi-dev.py --restore-ssh             # recovery guide if SSH is locked out
+
+SKIN DEVELOPMENT:
+  python3 xdj-pi-dev.py --screenshot              # grab screen, open in viewer
+  python3 xdj-pi-dev.py --screenshot --panel ks   # navigate to keyshift first
+  python3 xdj-pi-dev.py --restart                 # restart Mixxx
+  python3 xdj-pi-dev.py --push                    # push all skin files to Pi
+  python3 xdj-pi-dev.py --push "*.qss"            # push only matching files
+  python3 xdj-pi-dev.py --pull                    # pull skin files from Pi to repo
+  python3 xdj-pi-dev.py --push-midi               # push MIDI mapping to Pi
+  python3 xdj-pi-dev.py --pull-midi               # pull MIDI mapping from Pi
+  python3 xdj-pi-dev.py --midi-mon                # stream live MIDI messages (Ctrl-C to stop)
+  python3 xdj-pi-dev.py --watch [--panel PANEL]   # watch, auto-push, screenshot on save
+
+PICO FIRMWARE:
+  python3 xdj-pi-dev.py --setup-pico-cli          # install arduino-cli on Pi (one-time)
+  python3 xdj-pi-dev.py --pico-compile            # compile firmware on Pi (stops/restarts Mixxx)
+  python3 xdj-pi-dev.py --pico-compile --pico-bootloader  # compile + flash in one step
+  python3 xdj-pi-dev.py --pico-bootloader         # reset Pico to bootloader via MIDI
+  python3 xdj-pi-dev.py --pico-flash FILE.uf2     # flash a local .uf2 via Pi
+  python3 xdj-pi-dev.py --analyze                 # live GPIO signal analyzer (curses dashboard)
+
+OTHER:
+  python3 xdj-pi-dev.py --discover                # find all Pi units on the network
+  python3 xdj-pi-dev.py --cmd 'CMD'               # run arbitrary SSH command
+  python3 xdj-pi-dev.py --host 192.168.1.42       # target a specific IP/hostname
+
+PANEL NAMES (--panel):
+  hotcue | hc    beatloop | bl    keyshift | ks    beatjump | bj    stems | st
+
+MCP SERVER (Claude Code):
+  Add to ~/.claude.json under "mcpServers":
+    "xdj-pi": {
+      "command": "python3",
+      "args": ["/absolute/path/to/tools/xdj-pi-dev.py"]
+    }
+  Run with no arguments to start in MCP server mode.
+
+DEPENDENCIES:
+  pip install paramiko
+  pip install watchdog          # optional — faster file watching (falls back to polling)
+"""
+
+from __future__ import annotations
+
+import argparse
+import base64
+import concurrent.futures
+import fnmatch
+import itertools
+import json
+import os
+import shutil
+import socket
+import subprocess
+import sys
+import tempfile
+import textwrap
+import threading
+import time
+from pathlib import Path
+
+# ─── Dependency check ─────────────────────────────────────────────────────────
+
+try:
+    import paramiko
+except ImportError:
+    print("Missing dependency: paramiko")
+    print("Run:  pip install paramiko")
+    sys.exit(1)
+
+# ─── Configuration ────────────────────────────────────────────────────────────
+
+_DEFAULT_HOSTS = ["XDJ100SX.local", "192.168.10.2"]
+_TOOL_ABOUT = (__doc__ or "").split("FIRST RUN")[0].strip()
+
+PI_USER      = os.environ.get("XDJ_USER", "xdj100sx")
+PI_PASS      = os.environ.get("XDJ_PASS", "xdj100sx")
+PI_SKIN      = f"/home/{PI_USER}/.mixxx/skins/XDJ100SX"
+PI_MIXXX_ENV = f"DISPLAY=:0 XAUTHORITY=/home/{PI_USER}/.Xauthority"
+PI_PICO_PORT = "/dev/ttyACM0"
+
+# SSH key generated by --setup-ssh-keys (project-specific, won't affect other SSH usage)
+SSH_KEY_PATH = Path.home() / ".ssh" / "xdj_pi_ed25519"
+
+REPO_ROOT = Path(__file__).resolve().parent.parent
+REPO_SKIN = REPO_ROOT / "mixxx" / "SKIN" / "XDJ100SX"
+
+PANELS = {
+    "hotcue":   (368, 57), "hc":  (368, 57),
+    "beatloop": (464, 57), "bl":  (464, 57),
+    "keyshift": (560, 57), "ks":  (560, 57),
+    "beatjump": (656, 57), "bj":  (656, 57),
+    "stems":    (752, 57), "st":  (752, 57),
+}
+
+FILE_PANEL = {
+    "hotcues.xml":  "hotcue",
+    "beatloop.xml": "beatloop",
+    "keyshift.xml": "keyshift",
+    "beatjump.xml": "beatjump",
+    "stems.xml":    "stems",
+}
+
+REPO_MIDI    = REPO_ROOT / "mixxx" / "MIDI"
+PI_MIDI_DIR  = f"/home/{PI_USER}/.mixxx/controllers"
+MIDI_FILES   = ["XDJ100SX.midi.xml", "XDJ100SX.js"]
+
+
+# ─── Terminal UI ──────────────────────────────────────────────────────────────
+
+from xdj_pi_dev._terminal import _C, _COLOR, Step, section, ok, warn, fail, _log_line  # noqa: F401
+from xdj_pi_dev.messages import MSG
+from xdj_pi_dev.config import is_pico_board, get_board
+import itertools as _itertools  # used by Step spinner (re-exported via _terminal)
+# _tui_log_fn is managed in _terminal; expose it here for legacy callers
+import xdj_pi_dev._terminal as _term
+def _set_tui_log_fn(fn) -> None: _term._tui_log_fn = fn  # noqa: ANN001
+
+# ─── Platform helpers ─────────────────────────────────────────────────────────
+
+def open_image(path: Path) -> None:
+    """Open an image in the default viewer — macOS, Linux, Windows."""
+    s = str(path)
+    if sys.platform == "darwin":
+        subprocess.run(["open", s], check=False)
+    elif sys.platform == "win32":
+        os.startfile(s)
+    else:
+        subprocess.run(["xdg-open", s], check=False)
+
+
+def tmp_path(name: str) -> Path:
+    return Path(tempfile.gettempdir()) / name
+
+
+# ─── Network helpers ──────────────────────────────────────────────────────────
+
+def _port_open(host: str, port: int = 22, timeout: float = 2.0) -> bool:
+    try:
+        with socket.create_connection((host, port), timeout=timeout):
+            return True
+    except (socket.timeout, OSError):
+        return False
+
+
+def resolve_host(candidates: list[str]) -> str | None:
+    """Return the first candidate with port 22 reachable."""
+    for host in candidates:
+        if _port_open(host):
+            return host
+    return None
+
+
+def discover_units(extra_hosts: list[str] | None = None, subnet: str = "192.168.10") -> list[tuple[str, str]]:
+    """
+    Scan for Pi units: mDNS names first, then subnet sweep.
+    Returns list of (host, hostname) tuples for reachable units.
+    """
+    candidates: list[str] = list(extra_hosts or [])
+    candidates += ["XDJ100SX.local"] + [f"XDJ100SX-{i}.local" for i in range(1, 9)]
+    candidates += [f"{subnet}.{i}" for i in range(1, 255)]
+
+    def check(host: str) -> tuple[str, str] | None:
+        if not _port_open(host, timeout=0.4):
+            return None
+        try:
+            ssh = paramiko.SSHClient()
+            ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+            ssh.connect(host, username=PI_USER, password=PI_PASS,
+                        timeout=3, allow_agent=False, look_for_keys=False)
+            _, out, _ = ssh.exec_command("hostname", timeout=3)
+            hostname = out.read().decode().strip()
+            ssh.close()
+            return (host, hostname)
+        except Exception:
+            return None
+
+    print("Scanning… (this takes a few seconds)")
+    found: list[tuple[str, str]] = []
+    seen: set[str] = set()
+    with concurrent.futures.ThreadPoolExecutor(max_workers=60) as pool:
+        for r in pool.map(check, candidates):
+            if r and r[0] not in seen:
+                seen.add(r[0])
+                found.append(r)
+    return found
+
+
+def direct_cable_instructions() -> str:
+    """Platform-specific instructions for setting up the direct-cable network."""
+    if sys.platform == "darwin":
+        iface = "en0  (or en5/en6 if using a USB-C adapter — check: ifconfig | grep -B1 'inet 192')"
+        cmd   = "sudo ifconfig en0 alias 192.168.10.1 255.255.255.0"
+        note  = "Re-run after each Mac reboot (not persistent)."
+    elif sys.platform == "win32":
+        iface = "Ethernet (the interface connected to the Pi)"
+        cmd   = 'netsh interface ip set address "Ethernet" static 192.168.10.1 255.255.255.0'
+        note  = "Replace 'Ethernet' with the exact interface name from: ipconfig /all"
+    else:
+        iface = "eth0 (or enp3s0 / ens3 — check: ip link)"
+        cmd   = "sudo ip addr add 192.168.10.1/24 dev eth0"
+        note  = "To make it persistent: add to /etc/network/interfaces or create a NetworkManager connection."
+    return (
+        f"Interface: {iface}\n"
+        f"Command:   {cmd}\n"
+        f"Note:      {note}"
+    )
+
+
+# ─── Pi SSH/SFTP client ───────────────────────────────────────────────────────
+
+class PiClient:
+    def __init__(self, host: str, user: str, password: str):
+        self.host     = host
+        self.user     = user
+        self.password = password
+        self._ssh:  paramiko.SSHClient | None = None
+        self._sftp: paramiko.SFTPClient | None = None
+
+    def _alive(self) -> bool:
+        try:
+            t = self._ssh and self._ssh.get_transport()
+            return bool(t and t.is_active())
+        except Exception:
+            return False
+
+    def _connect(self) -> None:
+        ssh = paramiko.SSHClient()
+        ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+
+        # Try project key first if it exists, then fall back to password
+        if SSH_KEY_PATH.exists():
+            try:
+                ssh.connect(
+                    self.host, username=self.user,
+                    key_filename=str(SSH_KEY_PATH),
+                    look_for_keys=False, allow_agent=False, timeout=10,
+                )
+                self._ssh  = ssh
+                self._sftp = ssh.open_sftp()
+                return
+            except paramiko.AuthenticationException:
+                pass
+
+        ssh.connect(
+            self.host, username=self.user, password=self.password,
+            look_for_keys=False, allow_agent=False, timeout=10,
+        )
+        self._ssh  = ssh
+        self._sftp = ssh.open_sftp()
+
+    def _ok(self) -> None:
+        if not self._alive():
+            self._connect()
+
+    def exec(self, command: str, timeout: int = 30) -> dict:
+        self._ok()
+        assert self._ssh
+        _, stdout, stderr = self._ssh.exec_command(command, timeout=timeout)
+        out = stdout.read().decode(errors="replace")
+        err = stderr.read().decode(errors="replace")
+        rc  = stdout.channel.recv_exit_status()
+        return {"stdout": out, "stderr": err, "rc": rc}
+
+    def read_text(self, path: str) -> str:
+        self._ok()
+        assert self._sftp
+        with self._sftp.open(path, "rb") as f:
+            return f.read().decode(errors="replace")
+
+    def read_bytes(self, path: str) -> bytes:
+        self._ok()
+        assert self._sftp
+        with self._sftp.open(path, "rb") as f:
+            return f.read()
+
+    def write_text(self, path: str, content: str | bytes) -> None:
+        self.write_bytes(path, content.encode() if isinstance(content, str) else content)
+
+    def write_bytes(self, path: str, data: bytes) -> None:
+        self._ok()
+        assert self._sftp
+        with self._sftp.open(path, "wb") as f:
+            f.write(data)
+
+    def listdir(self, path: str) -> list[str]:
+        self._ok()
+        assert self._sftp
+        return sorted(self._sftp.listdir(path))
+
+    def exec_stream(self, command: str, timeout: int = 600) -> int:
+        """
+        Run command and feed each line through _log_line() as it arrives.
+        Returns the exit code.
+        """
+        self._ok()
+        assert self._ssh
+        transport = self._ssh.get_transport()
+        assert transport
+        channel = transport.open_session()
+        channel.set_combine_stderr(True)
+        channel.exec_command(command)
+
+        buf = b""
+        while True:
+            if channel.recv_ready():
+                buf += channel.recv(4096)
+                while b"\n" in buf:
+                    line, buf = buf.split(b"\n", 1)
+                    _log_line(line.decode(errors="replace").rstrip())
+            elif channel.exit_status_ready() and not channel.recv_ready():
+                break
+            else:
+                time.sleep(0.05)
+
+        if buf.strip():
+            _log_line(buf.decode(errors="replace").rstrip())
+
+        return channel.recv_exit_status()
+
+
+# Module-level client — set by init_client(); None until first successful connection
+pi: PiClient | None = None
+
+
+def init_client(host_override: str | None = None) -> str:
+    """Resolve target host, create the module-level PiClient, return host used."""
+    global pi, PI_USER, PI_PASS
+    from xdj_pi_dev.config import get_ssh_user, get_ssh_pass
+    PI_USER = get_ssh_user()
+    PI_PASS = get_ssh_pass()
+
+    if host_override:
+        candidates = [host_override]
+    else:
+        env = os.environ.get("XDJ_HOST")
+        candidates = [env] if env else _DEFAULT_HOSTS
+
+    host = resolve_host(candidates)
+    if not host:
+        tried = ", ".join(candidates)
+        msg = MSG["cant_reach_pi_detail"].format(
+            tried=tried,
+            instructions=textwrap.indent(direct_cable_instructions(), "  "),
+        )
+        # Raise so TUI worker catches it — sys.exit kills the whole TUI process
+        raise ConnectionError(msg)
+
+    pi = PiClient(host, PI_USER, PI_PASS)
+    return host
+
+
+# ─── Panel navigation ─────────────────────────────────────────────────────────
+
+def navigate_panel(panel_key: str) -> None:
+    key = panel_key.lower().strip()
+    coords = PANELS.get(key)
+    if not coords:
+        return
+    x, y = coords
+    pi.exec(f"{PI_MIXXX_ENV} xdotool mousemove {x} {y} click 1", timeout=5)
+    time.sleep(0.4)
+
+
+# ─── Actions ──────────────────────────────────────────────────────────────────
+
+def restart_mixxx(panel: str | None = None) -> str:
+    pi.exec("killall mixxx 2>/dev/null; true")
+    time.sleep(6)
+    result = pi.exec("pgrep -a mixxx")
+    pid = result["stdout"].strip()
+    msg = (f"Mixxx restarted (PID {pid.split()[0]})" if pid
+           else "WARNING: Mixxx PID not found — may still be starting")
+    if panel:
+        time.sleep(1)
+        navigate_panel(panel)
+    return msg
+
+
+def take_screenshot(panel: str | None = None) -> tuple[bytes | None, str | None]:
+    """Navigate to `panel` then capture. Returns (bytes, None) or (None, error)."""
+    if panel:
+        navigate_panel(panel)
+    pi.exec("rm -f /tmp/xdj_dev_screen.png")
+    r = pi.exec(f"{PI_MIXXX_ENV} scrot /tmp/xdj_dev_screen.png 2>&1", timeout=10)
+    if r["rc"] != 0:
+        return None, (r["stdout"] + r["stderr"]).strip()
+    return pi.read_bytes("/tmp/xdj_dev_screen.png"), None
+
+
+def _history_dir(base: Path, direction: str, ts: str) -> Path:
+    """direction: 'pushed' or 'pulled'. History lives inside the reference subject."""
+    return base / ".history" / direction / ts
+
+
+def push_skin(pattern: str = "*", backup_remote: bool = False) -> list[str]:
+    ts   = time.strftime("%Y%m%d-%H%M%S")
+    hist = _history_dir(REPO_SKIN.parent, "pushed", ts)
+    pushed = []
+    for f in sorted(REPO_SKIN.rglob("*")):
+        if f.is_file() and fnmatch.fnmatch(f.name, pattern):
+            rel    = f.relative_to(REPO_SKIN)
+            remote = f"{PI_SKIN}/{rel.as_posix()}"
+            if backup_remote:
+                pi.exec(f"cp -p '{remote}' '{remote}.bak-{ts}' 2>/dev/null || true")
+            data = f.read_bytes()
+            hist.mkdir(parents=True, exist_ok=True)
+            (hist / f.name).write_bytes(data)
+            pi.write_bytes(remote, data)
+            pushed.append(str(rel))
+    return pushed
+
+
+def push_midi(backup_remote: bool = False) -> list[str]:
+    """Push MIDI mapping files from docs/midi/ to ~/.mixxx/controllers/ on Pi."""
+    ts   = time.strftime("%Y%m%d-%H%M%S")
+    hist = _history_dir(REPO_MIDI, "pushed", ts)
+    pushed = []
+    for fname in MIDI_FILES:
+        local = REPO_MIDI / fname
+        if not local.exists():
+            warn(f"Not found locally: {local}")
+            continue
+        if backup_remote:
+            pi.exec(f"cp -p '{PI_MIDI_DIR}/{fname}' '{PI_MIDI_DIR}/{fname}.bak-{ts}' 2>/dev/null || true")
+        data = local.read_bytes()
+        hist.mkdir(parents=True, exist_ok=True)
+        (hist / fname).write_bytes(data)
+        pi.write_bytes(f"{PI_MIDI_DIR}/{fname}", data)
+        pushed.append(fname)
+    return pushed
+
+
+def pull_midi(backup: bool = False) -> list[str]:
+    """Pull MIDI mapping files from ~/.mixxx/controllers/ on Pi to docs/midi/."""
+    ts   = time.strftime("%Y%m%d-%H%M%S")
+    hist = _history_dir(REPO_MIDI, "pulled", ts)
+    pulled = []
+    for fname in MIDI_FILES:
+        remote = f"{PI_MIDI_DIR}/{fname}"
+        try:
+            data  = pi.read_bytes(remote)
+            local = REPO_MIDI / fname
+            if backup and local.exists():
+                local.rename(local.parent / f"{local.name}.bak-{ts}")
+            hist.mkdir(parents=True, exist_ok=True)
+            (hist / fname).write_bytes(data)
+            local.write_bytes(data)
+            pulled.append(fname)
+        except Exception as e:
+            warn(f"Skipped {fname}: {e}")
+    return pulled
+
+
+def pull_skin(backup: bool = False) -> list[str]:
+    ts   = time.strftime("%Y%m%d-%H%M%S")
+    hist = _history_dir(REPO_SKIN.parent, "pulled", ts)
+    pulled = []
+    for fname in pi.listdir(PI_SKIN):
+        remote = f"{PI_SKIN}/{fname}"
+        try:
+            data  = pi.read_bytes(remote)
+            local = REPO_SKIN / fname
+            if backup and local.exists():
+                local.rename(local.parent / f"{local.name}.bak-{ts}")
+            hist.mkdir(parents=True, exist_ok=True)
+            (hist / fname).write_bytes(data)
+            local.write_bytes(data)
+            pulled.append(fname)
+        except Exception as e:
+            warn(f"Skipped {fname}: {e}")
+    return pulled
+
+
+# ─── Pico firmware tools ──────────────────────────────────────────────────────
+
+from xdj_pi_dev.pico_tools import pico_bootloader, pico_flash  # noqa: F401
+
+# ─── MIDI monitor ─────────────────────────────────────────────────────────────
+
+from xdj_pi_dev.midi import midi_monitor  # noqa: F401
+
+# ─── Signal Analyzer ─────────────────────────────────────────────────────────
+
+from xdj_pi_dev.signal_analyzer import (
+    SA_PIN_NAMES, SA_BUTTON_PINS, SA_JOG_PINS, SA_BROWSE_PINS, SA_LED_PINS, SA_ALL_PINS,
+    run_signal_analyzer_web, run_signal_analyzer_cli,
+)
+
+
+# ─── Pico compile ─────────────────────────────────────────────────────────────
+
+from xdj_pi_dev.pico_tools import (
+    setup_pico_cli, pico_compile, DEFAULT_BOARD, BOARD_PROFILES,  # noqa: F401
+    REPO_FIRMWARE,
+)
+
+# ─── Setup commands ───────────────────────────────────────────────────────────
+
+from xdj_pi_dev.setup_cmds import (  # noqa: F401
+    setup_ssh_keys, restore_ssh, setup_pi_dhcp, set_hostname,
+)
+
+# ─── Pi image backup ──────────────────────────────────────────────────────────
+
+from xdj_pi_dev.backup import backup_pi_image, verify_backup  # noqa: F401
+
+# ─── Watch mode ───────────────────────────────────────────────────────────────
+
+from xdj_pi_dev.watch import watch_mode, _watch_loop  # noqa: F401
+
+# ─── Pre-flight check ─────────────────────────────────────────────────────────
+
+def run_check(host_override: str | None = None) -> None:
+    section("XDJ Pi Developer Tool — Pre-flight Check")
+
+    # 1. Python version
+    pv = sys.version_info
+    if pv >= (3, 8):
+        ok(f"Python {pv.major}.{pv.minor}.{pv.micro}")
+    else:
+        fail(f"Python {pv.major}.{pv.minor} — need 3.8+")
+
+    # 2. paramiko
+    ok(f"paramiko {paramiko.__version__}")
+
+    # 3. watchdog (optional)
+    try:
+        import watchdog
+        ver = getattr(watchdog, "__version__", "installed")
+        ok(f"watchdog {ver} (faster file watching)")
+    except ImportError:
+        warn("watchdog not installed — watch mode uses 1s polling. pip install watchdog")
+
+    # 4. ssh-keygen
+    if shutil.which("ssh-keygen"):
+        ok("ssh-keygen found")
+    else:
+        warn("ssh-keygen not found — --setup-ssh-keys won't work")
+
+    # 5. SSH key
+    if SSH_KEY_PATH.exists():
+        ok(f"Project SSH key: {SSH_KEY_PATH}")
+    else:
+        warn(f"No project SSH key yet — run --setup-ssh-keys for passwordless auth")
+
+    # 6. Repo skin dir
+    if REPO_SKIN.exists():
+        files = list(REPO_SKIN.glob("*.xml")) + list(REPO_SKIN.glob("*.qss"))
+        ok(f"Repo skin dir: {REPO_SKIN}  ({len(files)} skin files)")
+    else:
+        fail(f"Repo skin dir not found: {REPO_SKIN}")
+
+    print()
+    section("Network")
+
+    # 7. Resolve Pi
+    if host_override:
+        candidates = [host_override]
+    else:
+        env = os.environ.get("XDJ_HOST")
+        candidates = [env] if env else _DEFAULT_HOSTS
+
+    print(f"  Trying: {', '.join(candidates)}")
+    host = resolve_host(candidates)
+    if not host:
+        fail("Pi not reachable on port 22")
+        print()
+        print("  If using a direct cable, set up the network alias:")
+        print(textwrap.indent(direct_cable_instructions(), "  "))
+        print()
+        print("  Or run --setup-pi-dhcp after connecting via any route.")
+        return
+
+    ok(f"Pi reachable at: {host}")
+
+    global PI_USER, PI_PASS
+    pi_c = PiClient(host, PI_USER, PI_PASS)
+    global pi
+    pi = pi_c
+
+    # 8. SSH auth
+    try:
+        r = pi.exec("echo ssh_ok", timeout=8)
+        if "ssh_ok" in r["stdout"]:
+            auth_method = "key" if SSH_KEY_PATH.exists() else "password"
+            ok(f"SSH connected ({auth_method} auth)")
+        else:
+            fail("SSH connected but shell not responding")
+            return
+    except Exception as e:
+        fail(f"SSH auth failed: {e}")
+        print("  Check username/password or run --setup-ssh-keys")
+        return
+
+    print()
+    section("Pi Status")
+
+    # 9. Mixxx
+    r = pi.exec("pgrep -a mixxx")
+    if r["stdout"].strip():
+        pid = r["stdout"].strip().split()[0]
+        ok(f"Mixxx running (PID {pid})")
+    else:
+        warn("Mixxx not running")
+
+    # 10. Display
+    r = pi.exec(f"{PI_MIXXX_ENV} xdotool getactivewindow 2>/dev/null && echo display_ok || echo display_fail")
+    if "display_ok" in r["stdout"]:
+        ok("Display reachable (xdotool works)")
+    else:
+        warn("Display not reachable — screenshot/navigate won't work")
+
+    # 11. scrot
+    r = pi.exec("which scrot")
+    if r["rc"] == 0:
+        ok("scrot installed (screenshots work)")
+    else:
+        fail("scrot not installed on Pi — run: sudo apt install scrot")
+
+    # 12. Audio
+    r = pi.exec("aplay -l 2>/dev/null | grep card")
+    if r["stdout"].strip():
+        for line in r["stdout"].strip().splitlines():
+            ok(f"Audio: {line.strip()}")
+    else:
+        warn("No ALSA sound cards found")
+
+    # 13. MIDI (Pico)
+    r = pi.exec("ls /dev/ttyACM* 2>/dev/null || amidi -l 2>/dev/null | grep XDJ || echo none")
+    if "none" not in r["stdout"]:
+        ok(f"MIDI/serial device: {r['stdout'].strip()}")
+    else:
+        warn("No Pico/MIDI device found — check USB connection")
+
+    # 14. USB media
+    r = pi.exec("ls /media/ 2>/dev/null")
+    if r["stdout"].strip():
+        ok(f"USB media: /media/{r['stdout'].strip()}")
+    else:
+        warn("No USB media mounted (normal if no stick inserted)")
+
+    # 15. mDNS
+    r = pi.exec("hostname")
+    hostname = r["stdout"].strip()
+    ok(f"Pi hostname: {hostname}  ({hostname}.local via mDNS)")
+
+    # 16. dnsmasq (Pi DHCP)
+    r = pi.exec("systemctl is-active dnsmasq 2>/dev/null || echo inactive")
+    if r["stdout"].strip() == "active":
+        ok("dnsmasq running (Pi auto-assigns IPs to connected machines)")
+    else:
+        warn("dnsmasq not running — connected machines may need manual IP setup")
+        print("    Run --setup-pi-dhcp to fix this")
+
+    print()
+    print(f"  Connected to: {host}")
+    print()
+
+
+# ─── CLI status ───────────────────────────────────────────────────────────────
+
+def cli_status() -> None:
+    r = pi.exec(
+        "echo '=== Pi ===' && hostname && ip addr show eth0 | grep 'inet ' && "
+        "echo '=== Mixxx ===' && pgrep -a mixxx && "
+        "echo '=== Audio ===' && aplay -l 2>/dev/null | grep card && "
+        "echo '=== USB ===' && ls /media/ 2>/dev/null && "
+        "echo '=== Pico ===' && ls /dev/ttyACM* 2>/dev/null || true"
+    )
+    print(f"Connected to: {pi.host}")
+    print(r["stdout"])
+
+
+# ─── MCP server ───────────────────────────────────────────────────────────────
+
+MCP_TOOLS = [
+    {
+        "name": "run_command",
+        "description": "Run a shell command on the Pi via SSH.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {"command": {"type": "string"}},
+            "required": ["command"],
+        },
+    },
+    {
+        "name": "read_file",
+        "description": "Read a text file from the Pi.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {"path": {"type": "string", "description": "Absolute path on Pi"}},
+            "required": ["path"],
+        },
+    },
+    {
+        "name": "write_file",
+        "description": "Write a text file to the Pi.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {
+                "path":    {"type": "string"},
+                "content": {"type": "string"},
+            },
+            "required": ["path", "content"],
+        },
+    },
+    {
+        "name": "list_files",
+        "description": "List files in a Pi directory (default: skin dir).",
+        "inputSchema": {
+            "type": "object",
+            "properties": {"path": {"type": "string"}},
+        },
+    },
+    {
+        "name": "restart_mixxx",
+        "description": "Kill Mixxx and wait for xinitrc to restart it.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {
+                "panel": {
+                    "type": "string",
+                    "description": "Navigate to this panel after restart",
+                }
+            },
+        },
+    },
+    {
+        "name": "take_screenshot",
+        "description": "Capture the Pi display. Pass panel to navigate first.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {
+                "panel": {
+                    "type": "string",
+                    "description": "Panel tab to show before screenshotting",
+                }
+            },
+        },
+    },
+    {
+        "name": "navigate_panel",
+        "description": "Click a skin panel tab.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {"panel": {"type": "string"}},
+            "required": ["panel"],
+        },
+    },
+    {
+        "name": "push_skin_file",
+        "description": "Upload one skin file from the local repo to the Pi.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {"filename": {"type": "string"}},
+            "required": ["filename"],
+        },
+    },
+    {
+        "name": "pull_skin_file",
+        "description": "Download one skin file from the Pi to the local repo.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {"filename": {"type": "string"}},
+            "required": ["filename"],
+        },
+    },
+    {
+        "name": "push_skin",
+        "description": "Push all local skin files (or a glob subset) to the Pi.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {
+                "glob": {"type": "string", "description": "Filename glob, e.g. '*.qss'. Omit for all files."},
+            },
+        },
+    },
+    {
+        "name": "pull_skin",
+        "description": "Pull all skin files from Pi to local repo.",
+        "inputSchema": {"type": "object", "properties": {}},
+    },
+    {
+        "name": "push_midi",
+        "description": "Push local MIDI mapping files to Pi controllers directory.",
+        "inputSchema": {"type": "object", "properties": {}},
+    },
+    {
+        "name": "pull_midi",
+        "description": "Pull MIDI mapping files from Pi to local midi directory.",
+        "inputSchema": {"type": "object", "properties": {}},
+    },
+    {
+        "name": "check",
+        "description": "Run preflight: verify SSH connection, Mixxx status, Pico MIDI visibility.",
+        "inputSchema": {"type": "object", "properties": {}},
+    },
+    {
+        "name": "pico_bootloader",
+        "description": "Reset Pico into UF2 bootloader mode (MIDI trigger).",
+        "inputSchema": {"type": "object", "properties": {}},
+    },
+    {
+        "name": "pico_flash",
+        "description": "Flash a .uf2 file to the Pico.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {"local_path": {"type": "string"}},
+            "required": ["local_path"],
+        },
+    },
+    {
+        "name": "discover_units",
+        "description": "Scan the network for all reachable XDJ Pi units. Returns hostnames and IPs.",
+        "inputSchema": {"type": "object", "properties": {}},
+    },
+    {
+        "name": "select_unit",
+        "description": "Switch the active connection to a specific XDJ Pi unit by hostname or IP.",
+        "inputSchema": {
+            "type": "object",
+            "properties": {"host": {"type": "string", "description": "Hostname or IP of the unit to connect to"}},
+            "required": ["host"],
+        },
+    },
+]
+
+
+def _call_tool(name: str, args: dict) -> list[dict]:
+    if name == "run_command":
+        r = pi.exec(args["command"])
+        parts = []
+        if r["stdout"]: parts.append(r["stdout"].rstrip())
+        if r["stderr"]: parts.append(f"[stderr] {r['stderr'].rstrip()}")
+        parts.append(f"[exit {r['rc']}]")
+        return [{"type": "text", "text": "\n".join(parts)}]
+
+    if name == "read_file":
+        return [{"type": "text", "text": pi.read_text(args["path"])}]
+
+    if name == "write_file":
+        pi.write_text(args["path"], args["content"])
+        return [{"type": "text", "text": f"Written: {args['path']}"}]
+
+    if name == "list_files":
+        files = pi.listdir(args.get("path", PI_SKIN))
+        return [{"type": "text", "text": "\n".join(files)}]
+
+    if name == "restart_mixxx":
+        return [{"type": "text", "text": restart_mixxx(panel=args.get("panel"))}]
+
+    if name == "take_screenshot":
+        data, err = take_screenshot(panel=args.get("panel"))
+        if err:
+            return [{"type": "text", "text": f"Screenshot failed: {err}"}]
+        return [{"type": "image", "data": base64.b64encode(data).decode(), "mimeType": "image/png"}]
+
+    if name == "navigate_panel":
+        navigate_panel(args["panel"])
+        return [{"type": "text", "text": f"Navigated to {args['panel']}"}]
+
+    if name == "push_skin_file":
+        fname = args["filename"]
+        local = REPO_SKIN / fname
+        if not local.exists():
+            return [{"type": "text", "text": f"Not found locally: {local}"}]
+        pi.write_bytes(f"{PI_SKIN}/{fname}", local.read_bytes())
+        return [{"type": "text", "text": f"Pushed {fname} → Pi"}]
+
+    if name == "pull_skin_file":
+        fname = args["filename"]
+        data  = pi.read_bytes(f"{PI_SKIN}/{fname}")
+        local = REPO_SKIN / fname
+        local.parent.mkdir(parents=True, exist_ok=True)
+        local.write_bytes(data)
+        return [{"type": "text", "text": f"Pulled {fname} → {local}"}]
+
+    if name == "push_skin":
+        pushed = push_skin(glob=args.get("glob", "*"))
+        return [{"type": "text", "text": f"Pushed {len(pushed)} file(s): {', '.join(pushed)}"}]
+
+    if name == "pull_skin":
+        pulled = pull_skin()
+        return [{"type": "text", "text": f"Pulled {len(pulled)} file(s): {', '.join(pulled)}"}]
+
+    if name == "push_midi":
+        pushed = push_midi()
+        return [{"type": "text", "text": f"Pushed {len(pushed)} MIDI file(s): {', '.join(pushed)}"}]
+
+    if name == "pull_midi":
+        pulled = pull_midi()
+        return [{"type": "text", "text": f"Pulled {len(pulled)} MIDI file(s): {', '.join(pulled)}"}]
+
+    if name == "check":
+        import io, contextlib
+        buf = io.StringIO()
+        with contextlib.redirect_stdout(buf):
+            run_check()
+        return [{"type": "text", "text": buf.getvalue()}]
+
+    if name == "pico_bootloader":
+        return [{"type": "text", "text": pico_bootloader(pi)}]
+
+    if name == "pico_flash":
+        return [{"type": "text", "text": pico_flash(pi, args["local_path"])}]
+
+    if name == "discover_units":
+        units = discover_units()
+        if not units:
+            return [{"type": "text", "text": "No XDJ Pi units found on the network."}]
+        lines = "\n".join(f"  {host}  ({hostname})" for host, hostname in units)
+        return [{"type": "text", "text": f"Found {len(units)} unit(s):\n{lines}"}]
+
+    if name == "select_unit":
+        host = init_client(host_override=args["host"])
+        return [{"type": "text", "text": f"Switched active connection to: {host}"}]
+
+    return [{"type": "text", "text": f"Unknown tool: {name}"}]
+
+
+def _mcp_send(obj: dict) -> None:
+    sys.stdout.buffer.write(json.dumps(obj).encode() + b"\n")
+    sys.stdout.buffer.flush()
+
+
+def run_mcp_server() -> None:
+    print("XDJ Pi MCP server started.", file=sys.stderr)
+    print("For CLI use: python3 xdj-pi-dev.py --help", file=sys.stderr)
+    for line in sys.stdin.buffer:
+        line = line.strip()
+        if not line:
+            continue
+        try:
+            msg = json.loads(line)
+        except json.JSONDecodeError:
+            continue
+        method = msg.get("method", "")
+        rid    = msg.get("id")
+
+        if method == "initialize":
+            _mcp_send({
+                "jsonrpc": "2.0", "id": rid,
+                "result": {
+                    "protocolVersion": "2024-11-05",
+                    "capabilities": {"tools": {}},
+                    "serverInfo": {"name": "xdj-pi-dev", "version": "3.0.0"},
+                },
+            })
+        elif method == "notifications/initialized":
+            pass
+        elif method == "tools/list":
+            _mcp_send({"jsonrpc": "2.0", "id": rid, "result": {"tools": MCP_TOOLS}})
+        elif method == "tools/call":
+            p = msg.get("params", {})
+            try:
+                content = _call_tool(p.get("name", ""), p.get("arguments", {}))
+                _mcp_send({"jsonrpc": "2.0", "id": rid, "result": {"content": content}})
+            except Exception as exc:
+                _mcp_send({
+                    "jsonrpc": "2.0", "id": rid,
+                    "error": {"code": -32000, "message": str(exc)},
+                })
+        elif rid is not None:
+            _mcp_send({
+                "jsonrpc": "2.0", "id": rid,
+                "error": {"code": -32601, "message": f"Unknown method: {method}"},
+            })
+
+
+# ─── Main ─────────────────────────────────────────────────────────────────────
+
+# ─── Textual TUI ──────────────────────────────────────────────────────────────
+
+try:
+    from textual.app import App, ComposeResult
+    from textual.binding import Binding
+    from textual.containers import Horizontal, Vertical, ScrollableContainer
+    from textual.screen import ModalScreen
+    from textual.widgets import Button, Footer, Header, Input, Label, RichLog, Static
+    from textual import work as _twork
+    _TEXTUAL = True
+except ImportError:
+    _TEXTUAL = False
+
+
+if _TEXTUAL:
+    from textual.widgets import Select  # noqa: E402
+
+    _BOARD_META = {
+        "pico":    ("Raspberry Pi Pico",   "Full support — recommended"),
+        "pico2":   ("Raspberry Pi Pico 2", "Full support"),
+        "teensy":  ("Teensy 4.x",          "Skin & MIDI only (design phase)"),
+        "unknown": ("Other / unknown",     "Skin & MIDI tools only"),
+    }
+
+    _BOARD_SPECS = {
+        "pico":    "MCU: RP2040 · 133 MHz\nRAM: 264 KB · Flash: 2 MB\nUSB boot (UF2)",
+        "pico2":   "MCU: RP2350 · 150 MHz\nRAM: 520 KB · Flash: 4 MB\nUSB boot (UF2)",
+        "teensy":  "MCU: iMXRT1062 · 600 MHz\nRAM: 1 MB · Flash: 2 MB\nUSB native",
+        "unknown": "Use if you're not sure.\nSkin & MIDI tools work\nfor any board.",
+    }
+
+    class BoardSelectScreen(ModalScreen):  # type: ignore[misc]
+        """Board selection screen — shows board images with background removed."""
+
+        DEFAULT_CSS = """
+        BoardSelectScreen { align: center middle; }
+
+        #board-dialog {
+            background: $panel;
+            border: solid $primary;
+            padding: 1 2;
+            width: 88;
+            height: auto;
+        }
+        #board-title {
+            width: 100%;
+            text-align: center;
+            text-style: bold;
+            color: $primary;
+            margin-bottom: 1;
+        }
+        #board-cards {
+            layout: horizontal;
+            height: auto;
+            width: 100%;
+        }
+        .board-card {
+            width: 1fr;
+            height: auto;
+            border: tall $panel-lighten-3;
+            padding: 0 1;
+            margin: 0 1;
+            background: $panel-lighten-1;
+        }
+        .board-card.-selected {
+            border: tall $primary;
+            background: $panel-lighten-2;
+        }
+        .board-specs {
+            width: 100%;
+            color: $text-muted;
+            margin-bottom: 1;
+            height: 5;
+        }
+        .board-name {
+            width: 100%;
+            text-align: center;
+            text-style: bold;
+            color: $text;
+        }
+        .board-desc {
+            width: 100%;
+            text-align: center;
+            color: $text-muted;
+        }
+        .btn-sel {
+            width: 100%;
+            margin-top: 1;
+        }
+        #board-footer {
+            width: 100%;
+            align: right middle;
+            height: 3;
+            margin-top: 1;
+        }
+        """
+
+        def __init__(self, current: str = "pico") -> None:
+            super().__init__()
+            self._selected = current
+
+        def compose(self) -> ComposeResult:
+            with Vertical(id="board-dialog"):
+                yield Label("What's inside your DJ unit?", id="board-title")
+                with Horizontal(id="board-cards"):
+                    for key, (name, desc) in _BOARD_META.items():
+                        is_sel = key == self._selected
+                        card_cls = "board-card" + (" -selected" if is_sel else "")
+                        with Vertical(classes=card_cls, id=f"card-{key}"):
+                            yield Static(
+                                _BOARD_SPECS.get(key, ""),
+                                classes="board-specs",
+                            )
+                            yield Label(name, classes="board-name")
+                            yield Label(desc, classes="board-desc")
+                            yield Button(
+                                "✓ Selected" if is_sel else "Select",
+                                id=f"btn-sel-{key}",
+                                variant="primary" if is_sel else "default",
+                                classes="btn-sel",
+                            )
+                with Horizontal(id="board-footer"):
+                    yield Button("Save & Continue →", id="btn-board-save", variant="success")
+
+        def on_button_pressed(self, event: Button.Pressed) -> None:
+            event.stop()
+            bid = event.button.id or ""
+
+            if bid == "btn-board-save":
+                from xdj_pi_dev.config import update_config
+                update_config(board=self._selected)
+                self.dismiss(self._selected)
+
+            elif bid.startswith("btn-sel-"):
+                self._select(bid[len("btn-sel-"):])
+
+        def _select(self, key: str) -> None:
+            if key == self._selected:
+                return
+            # Deselect old
+            try:
+                self.query_one(f"#card-{self._selected}").remove_class("-selected")
+                old_btn = self.query_one(f"#btn-sel-{self._selected}", Button)
+                old_btn.label = "Select"
+                old_btn.variant = "default"
+            except Exception:
+                pass
+            # Select new
+            self._selected = key
+            try:
+                self.query_one(f"#card-{key}").add_class("-selected")
+                new_btn = self.query_one(f"#btn-sel-{key}", Button)
+                new_btn.label = "✓ Selected"
+                new_btn.variant = "primary"
+            except Exception:
+                pass
+
+        def on_key(self, event) -> None:
+            if event.key == "escape":
+                self.dismiss(None)
+
+    class ConfirmScreen(ModalScreen):  # type: ignore[misc]
+        """Generic two-option confirm modal."""
+
+        def __init__(self, title: str, ok_label: str, ok_key: str, alt_label: str, alt_key: str) -> None:
+            super().__init__()
+            self._title     = title
+            self._ok_label  = ok_label
+            self._alt_label = alt_label
+            self._ok_key    = ok_key
+            self._alt_key   = alt_key
+
+        def compose(self) -> ComposeResult:
+            with Vertical(id="confirm-box"):
+                yield Label(self._title)
+                yield Button(self._ok_label,  id="cb-ok",  variant="primary")
+                yield Button(self._alt_label, id="cb-alt")
+                yield Button("Cancel",        id="cb-cancel", variant="error")
+
+        def on_button_pressed(self, event: Button.Pressed) -> None:
+            event.stop()  # prevent bubbling to XDJApp.on_button_pressed
+            if   event.button.id == "cb-ok":     self.dismiss(self._ok_key)
+            elif event.button.id == "cb-alt":    self.dismiss(self._alt_key)
+            elif event.button.id == "cb-cancel": self.dismiss(None)
+
+        def on_key(self, event) -> None:
+            if event.key == "escape":
+                self.dismiss(None)
+
+    class SettingsScreen(ModalScreen):  # type: ignore[misc]
+        """Full settings: SSH credentials + board selection."""
+
+        DEFAULT_CSS = """
+        SettingsScreen { align: center middle; }
+        #settings-dialog {
+            background: $panel;
+            border: solid $primary;
+            padding: 1 2;
+            width: 60;
+            height: auto;
+        }
+        #settings-title {
+            width: 100%;
+            text-align: center;
+            text-style: bold;
+            color: $primary;
+            margin-bottom: 1;
+        }
+        .settings-section {
+            color: $primary;
+            text-style: bold;
+            margin-top: 1;
+        }
+        .settings-row { height: 3; margin-bottom: 0; }
+        .field-label { width: 12; color: $text-muted; padding-top: 1; }
+        .field-input { width: 1fr; }
+        #settings-board { width: 100%; margin-top: 1; margin-bottom: 0; }
+        #settings-footer {
+            width: 100%;
+            align: right middle;
+            height: 3;
+            margin-top: 1;
+        }
+        #settings-footer Button { width: auto; min-width: 16; margin-left: 1; }
+        """
+
+        def __init__(self) -> None:
+            super().__init__()
+            from xdj_pi_dev.config import load_config
+            cfg = load_config()
+            self._init_user  = cfg.get("ssh_user", "")
+            self._init_pass  = cfg.get("ssh_pass", "")
+            self._init_board = cfg.get("board", "pico")
+
+        def compose(self) -> ComposeResult:
+            board_options = [(_BOARD_META[k][0], k) for k in _BOARD_META]
+            with Vertical(id="settings-dialog"):
+                yield Label("Settings", id="settings-title")
+                yield Label("SSH CREDENTIALS", classes="settings-section")
+                with Horizontal(classes="settings-row"):
+                    yield Label("Username:", classes="field-label")
+                    yield Input(
+                        value=self._init_user,
+                        placeholder="xdj100sx",
+                        id="inp-user",
+                        classes="field-input",
+                    )
+                with Horizontal(classes="settings-row"):
+                    yield Label("Password:", classes="field-label")
+                    yield Input(
+                        value=self._init_pass,
+                        placeholder="xdj100sx",
+                        password=True,
+                        id="inp-pass",
+                        classes="field-input",
+                    )
+                yield Label("BOARD", classes="settings-section")
+                yield Select(board_options, id="settings-board", value=self._init_board)
+                with Horizontal(id="settings-footer"):
+                    yield Button("Save & Close", id="btn-st-save", variant="success")
+                    yield Button("Cancel",        id="btn-st-cancel")
+
+        def on_button_pressed(self, event: Button.Pressed) -> None:
+            event.stop()
+            if event.button.id == "btn-st-save":
+                from xdj_pi_dev.config import update_config
+                user   = self.query_one("#inp-user",  Input).value.strip()
+                passwd = self.query_one("#inp-pass",  Input).value.strip()
+                bsel   = self.query_one("#settings-board", Select)
+                board  = str(bsel.value) if bsel.value and bsel.value is not Select.BLANK else "pico"
+                update_config(ssh_user=user or None, ssh_pass=passwd or None, board=board)
+                self.dismiss(board)
+            elif event.button.id == "btn-st-cancel":
+                self.dismiss(None)
+
+        def on_key(self, event) -> None:
+            if event.key == "escape":
+                self.dismiss(None)
+
+    class AboutScreen(ModalScreen):  # type: ignore[misc]
+        """Authors, credits, and legal notices."""
+
+        DEFAULT_CSS = """
+        AboutScreen { align: center middle; }
+        #about-dialog {
+            background: $panel;
+            border: solid $primary;
+            padding: 1 2;
+            width: 72;
+            height: auto;
+            max-height: 44;
+        }
+        #about-title {
+            width: 100%;
+            text-align: center;
+            text-style: bold;
+            color: $primary;
+            margin-bottom: 1;
+        }
+        #about-body {
+            height: 30;
+            overflow-y: auto;
+        }
+        #about-footer {
+            width: 100%;
+            align: center middle;
+            height: 3;
+            margin-top: 1;
+        }
+        """
+
+        _ABOUT = _TOOL_ABOUT
+
+        def compose(self) -> ComposeResult:
+            with Vertical(id="about-dialog"):
+                yield Static("XDJ-100SX Pi Developer Tool", id="about-title")
+                with ScrollableContainer(id="about-body"):
+                    yield Static(self._ABOUT)
+                with Horizontal(id="about-footer"):
+                    yield Button("Close", id="btn-about-close", variant="primary")
+
+        def on_button_pressed(self, event: Button.Pressed) -> None:
+            event.stop()
+            if event.button.id == "btn-about-close":
+                self.dismiss()
+
+        def on_key(self, event) -> None:
+            if event.key == "escape":
+                self.dismiss()
+
+    class HelpScreen(ModalScreen):  # type: ignore[misc]
+        """First-connection guide — how to reach the Pi."""
+
+        DEFAULT_CSS = """
+        HelpScreen { align: center middle; }
+        #help-dialog {
+            background: $panel;
+            border: solid $primary;
+            padding: 1 2;
+            width: 72;
+            height: auto;
+            max-height: 44;
+        }
+        #help-title {
+            width: 100%;
+            text-align: center;
+            text-style: bold;
+            color: $primary;
+            margin-bottom: 1;
+        }
+        #help-body {
+            height: 30;
+            overflow-y: auto;
+        }
+        #help-footer {
+            width: 100%;
+            align: center middle;
+            height: 3;
+            margin-top: 1;
+        }
+        """
+
+        _GUIDE = """\
+━━━ OPTION 1 — XDJ100SX.local  [dim](any network, WiFi or LAN)[/] ━━━
+
+Pi and your computer must be on the same network.
+
+[bold]Pi side[/] — needs avahi-daemon (check it's running):
+[dim]  sudo systemctl enable --now avahi-daemon[/]
+[dim]  sudo apt install -y avahi-daemon    ← if not installed[/]
+
+[bold]macOS[/] — Bonjour is built-in. Nothing to install.
+
+[bold]Windows 10/11[/] — mDNS is built-in but Windows Firewall
+  often blocks it. If XDJ100SX.local doesn't resolve:
+  • Use the IP address (192.168.10.2) instead, or
+  • Install [bold]Bonjour Print Services for Windows[/] (free, from Apple)
+
+[bold]Linux[/] — install avahi-daemon on your machine too:
+[dim]  sudo apt install avahi-daemon[/]
+
+
+━━━ OPTION 2 — 192.168.10.2  [dim](direct Ethernet cable)[/] ━━━
+
+No router needed. Faster and more stable for development.
+
+[bold]PI SIDE — configure static IP[/] (skip if already done):
+[dim]  sudo nmcli con mod eth0 \\[/]
+[dim]    ipv4.method manual \\[/]
+[dim]    ipv4.addresses 192.168.10.2/24 \\[/]
+[dim]    ipv4.gateway "" ipv4.dns "" \\[/]
+[dim]    connection.autoconnect yes[/]
+[dim]  sudo nmcli con up eth0[/]
+
+[bold]YOUR MACHINE — set a matching IP on the cable port:[/]
+
+macOS  (once per reboot — check interface with: ifconfig | grep -B2 'status: active'):
+[dim]  sudo ifconfig en0 alias 192.168.10.1 255.255.255.0[/]
+
+Windows  (run as Administrator, once per reboot):
+[dim]  netsh interface ip set address "Ethernet" static 192.168.10.1 255.255.255.0[/]
+[dim]  ← replace "Ethernet" with your interface name (check: ipconfig /all)[/]
+
+Linux:
+[dim]  sudo ip addr add 192.168.10.1/24 dev eth0[/]
+
+Or run [bold]--setup-pi-dhcp[/] once — Pi assigns IPs automatically,
+no local config needed ever again.
+
+
+━━━ OPTION 3 — Custom IP or hostname ━━━
+
+Type any address in the top field and press Enter.
+It gets added to the dropdown for quick switching.
+
+
+━━━ IT'S NOT CONNECTING? ━━━
+
+[bold]1. Enable SSH on the Pi[/]  (run on the Pi itself or via its keyboard):
+[dim]  sudo systemctl enable ssh && sudo systemctl start ssh[/]
+
+[bold]2. Allow password login[/]  (newer Pi OS blocks it by default):
+[dim]  sudo nano /etc/ssh/sshd_config[/]
+[dim]  → find or add:  PasswordAuthentication yes[/]
+[dim]  sudo systemctl restart ssh[/]
+
+[bold]3. Wrong password?[/]  Open Settings (⚙) → enter your credentials.
+
+[bold]4. Full pre-flight check:[/]
+[dim]  python3 xdj-pi-dev.py --check    ← macOS / Linux[/]
+[dim]  python  xdj-pi-dev.py --check    ← Windows[/]
+"""
+
+        def compose(self) -> ComposeResult:
+            with Vertical(id="help-dialog"):
+                yield Label("First Connection Guide", id="help-title")
+                with ScrollableContainer(id="help-body"):
+                    yield Static(self._GUIDE)
+                with Horizontal(id="help-footer"):
+                    yield Button("Close", id="btn-help-close", variant="primary")
+
+        def on_button_pressed(self, event: Button.Pressed) -> None:
+            event.stop()
+            self.dismiss(None)
+
+        def on_key(self, event) -> None:
+            if event.key == "escape":
+                self.dismiss(None)
+
+    class XDJApp(App):  # type: ignore[misc]
+        TITLE = "XDJ Pi Dev"
+
+        CSS = """
+        Screen { layout: vertical; }
+
+        #top-bar {
+            height: 3;
+            background: $panel;
+            border-bottom: solid $primary-darken-2;
+            padding: 0 1;
+            align: left middle;
+        }
+        #unit-select { width: 34; margin-right: 1; }
+        #host-input  { width: 30; margin-right: 1; }
+        #status { width: 1fr; color: $text-muted; }
+
+        Input {
+            background: $panel-lighten-1;
+            border: tall $panel-lighten-3;
+            color: $text;
+        }
+        Input:focus { border: tall $primary; }
+
+        #body { layout: horizontal; height: 1fr; }
+
+        #sidebar {
+            width: 20;
+            background: $panel;
+            border-right: solid $primary-darken-2;
+            padding: 1 1;
+            overflow-y: auto;
+        }
+
+        /* Section headers */
+        .sec {
+            color: $primary;
+            text-style: bold;
+            margin-top: 1;
+            margin-bottom: 0;
+            padding: 0 0;
+        }
+        .sec-first { margin-top: 0; }
+
+        /* All sidebar buttons */
+        Button {
+            width: 100%;
+            height: 1;
+            min-height: 1;
+            border: none;
+            padding: 0 1;
+            background: $panel-lighten-1;
+            color: $text;
+            margin-bottom: 0;
+        }
+        Button:hover          { background: $primary-darken-1; color: $text; }
+        Button:focus          { border: none; }
+        Button.-primary       { background: $primary;          color: $text; }
+        Button.-warning       { background: $warning;          color: $text-muted; }
+        Button.-active-watch  { background: $warning 80%;      color: $text; }
+
+        /* Main log area */
+        #main { padding: 0 1; height: 1fr; }
+        #log  { border: solid $primary-darken-3; height: 1fr; }
+
+        /* SSH command bar */
+        #ssh-bar {
+            height: 3;
+            padding: 0 0;
+            background: $panel;
+            border-top: solid $primary-darken-2;
+        }
+        #cmd-input { width: 1fr; border: none; }
+
+        /* Bottom log-control strip */
+        #log-bar {
+            height: 1;
+            background: $panel;
+            border-top: solid $primary-darken-2;
+            padding: 0 1;
+            align: left middle;
+        }
+        #log-bar Button {
+            width: auto;
+            min-width: 12;
+            margin-right: 1;
+            background: $panel-lighten-2;
+        }
+        #log-bar Button:hover { background: $primary-darken-1; }
+
+        /* Confirm dialog modal */
+        ConfirmScreen, .modal {
+            align: center middle;
+        }
+        #confirm-box {
+            background: $panel;
+            border: solid $primary;
+            padding: 1 2;
+            width: 44;
+            height: auto;
+        }
+        #confirm-box Label {
+            width: 100%;
+            margin-bottom: 1;
+            text-style: bold;
+        }
+        #confirm-box Button {
+            width: 100%;
+            margin-bottom: 0;
+        }
+        """
+
+        BINDINGS = [
+            Binding("x",       "quit",        "Quit"),
+            Binding("p",       "push",        "Push skin"),
+            Binding("s",       "screenshot",  "Screenshot"),
+            Binding("r",       "restart",     "Restart"),
+            Binding("w",       "watch",       "Watch"),
+            Binding("d",       "discover",    "Discover"),
+            Binding("ctrl+c",  "copy_log",    "Copy log"),
+            Binding("ctrl+y",  "copy_tail",   "Copy tail"),
+            Binding("l",       "clear_log",   "Clear log"),
+        ]
+
+        def __init__(self, host: str | None = None) -> None:
+            super().__init__()
+            self._host = host
+            self._known_hosts: list[str] = [host] if host else list(_DEFAULT_HOSTS)
+            self._watching = False
+            self._watch_stop = threading.Event()
+            self._midi_mon = False
+            self._midi_mon_stop = threading.Event()
+            self._signal_an = False
+            self._signal_an_stop = threading.Event()
+            # Prevents on_select_changed from firing a reconnect during programmatic updates
+            self._unit_switching = False
+            # Prevents concurrent connections (one at a time)
+            self._connect_lock = threading.Lock()
+            # Prevents concurrent SSH operations (push, screenshot, flash, etc.)
+            self._op_lock = threading.Lock()
+            # Keeps a plain-text copy of every log line for clipboard export
+            self._log_lines: list[str] = []
+
+        @staticmethod
+        def _select_labels(hosts: list[str]) -> list[tuple[str, str]]:
+            _WELL_KNOWN = {
+                "XDJ100SX.local": "XDJ100SX.local  (mDNS — any network)",
+                "192.168.10.2":   "192.168.10.2  (direct cable)",
+            }
+            return [(_WELL_KNOWN.get(h, h), h) for h in hosts]
+
+        def compose(self) -> ComposeResult:
+            yield Header(show_clock=True)
+            with Horizontal(id="top-bar"):
+                yield Select(
+                    self._select_labels(self._known_hosts),
+                    id="unit-select",
+                    prompt="Select unit…",
+                    # value is set in on_mount after _unit_switching=True to avoid a
+                    # spurious on_select_changed that would trigger a second connect
+                )
+                yield Input(placeholder="or type IP / hostname…", id="host-input")
+                yield Static("Connecting…", id="status")
+            with Horizontal(id="body"):
+                with Vertical(id="sidebar"):
+                    yield Button("⚙ Settings",       id="btn-settings", variant="warning")
+                    yield Button("? Connect Help",   id="btn-help")
+                    yield Button("ℹ About",           id="btn-about")
+                    yield Label("DEPLOY",           classes="sec sec-first")
+                    yield Button("Push Skin",        id="btn-push",       variant="primary")
+                    yield Button("Pull Skin",        id="btn-pull")
+                    yield Button("Push MIDI",        id="btn-push-midi")
+                    yield Button("Pull MIDI",        id="btn-pull-midi")
+                    yield Button("Screenshot",       id="btn-screenshot")
+                    yield Button("Restart",          id="btn-restart",    variant="warning")
+                    yield Label("LIVE",              classes="sec")
+                    yield Button("Watch ▶",          id="btn-watch")
+                    yield Button("MIDI Mon ▶",       id="btn-midi-mon")
+                    # PICO-specific — always mounted, visibility set by _apply_board_visibility
+                    yield Button("Signal An ▶",      id="btn-signal-an")
+                    yield Label("PICO",              classes="sec", id="lbl-pico")
+                    yield Button("Bootloader",       id="btn-bootloader")
+                    yield Button("Flash UF2",        id="btn-flash")
+                    yield Label("TOOLS",             classes="sec")
+                    yield Button("Discover",         id="btn-discover")
+                    yield Button("Check",            id="btn-check")
+                    yield Button("Backup Pi",        id="btn-backup")
+                    yield Button("Verify Bak",       id="btn-verify-backup")
+                    yield Button("SSH Keys",         id="btn-ssh-keys")
+                    yield Button("DHCP",             id="btn-dhcp")
+                with Vertical(id="main"):
+                    yield RichLog(id="log", highlight=True, markup=True, max_lines=500)
+                    with Horizontal(id="ssh-bar"):
+                        yield Input(placeholder="$ command on Pi…", id="cmd-input")
+            with Horizontal(id="log-bar"):
+                yield Button("Copy Log",  id="btn-copy-log")
+                yield Button("Copy Tail", id="btn-copy-tail")
+                yield Button("Clear Log", id="btn-clear-log")
+            yield Footer()
+
+        def on_mount(self) -> None:
+            _term._tui_log_fn = self._log_from_thread
+            self._unit_switching = True
+            initial = self._host or _DEFAULT_HOSTS[0]
+            self.query_one("#unit-select", Select).value = initial
+            self._apply_board_visibility()
+            from xdj_pi_dev.config import load_config
+            if "board" not in load_config():
+                # First run — show board selector before connecting
+                self.push_screen(
+                    BoardSelectScreen(current="pico"),
+                    lambda choice: self._after_first_board(choice, initial),
+                )
+            else:
+                self._do_connect(initial)
+
+        def _after_first_board(self, choice: str | None, initial: str) -> None:
+            # ESC on first-run = accept default (pico). Don't leave config empty
+            # or the selector would show again on every launch.
+            from xdj_pi_dev.config import update_config
+            update_config(board=choice or "pico")
+            self._apply_board_visibility()
+            self._do_connect(initial)
+
+        # ── Thread-safe log ───────────────────────────────────────────────────
+
+        def _log_from_thread(self, level: str, msg: str) -> None:
+            self.call_from_thread(self._log, level, msg)
+
+        def _log(self, level: str, msg: str) -> None:
+            icons = {
+                "ok":   "[green]✓[/]",
+                "warn": "[yellow]⚠[/]",
+                "fail": "[red]✗[/]",
+                "info": "[dim]·[/]",
+                "head": "[bold cyan]╌[/]",
+            }
+            self._log_lines.append(f"{level.upper()}: {msg}")
+            self.query_one("#log", RichLog).write(f"{icons.get(level, '·')} {msg}")
+
+        def _set_status(self, text: str) -> None:
+            self.query_one("#status", Static).update(text)
+
+        def _clear_switching(self) -> None:
+            self._unit_switching = False
+
+        def _op_start(self) -> bool:
+            """Try to acquire the operation lock. Returns False if not ready or busy."""
+            if pi is None:
+                self._log_from_thread("warn", MSG["not_connected"])
+                return False
+            if not self._op_lock.acquire(blocking=False):
+                self._log_from_thread("warn", MSG["busy"])
+                return False
+            return True
+
+        def _op_end(self) -> None:
+            try:
+                self._op_lock.release()
+            except RuntimeError:
+                pass
+
+        # ── Unit switcher ─────────────────────────────────────────────────────
+
+        def on_select_changed(self, event: Select.Changed) -> None:
+            if event.select.id != "unit-select" or self._unit_switching:
+                return
+            if event.value and event.value is not Select.BLANK:
+                self._unit_switching = True
+                self._do_connect(str(event.value))
+
+        def on_input_submitted(self, event: Input.Submitted) -> None:
+            iid = event.input.id
+            if iid == "host-input":
+                host = event.value.strip()
+                if host:
+                    event.input.value = ""
+                    self._connect_to_custom(host)
+            elif iid == "cmd-input":
+                cmd = event.value.strip()
+                if cmd:
+                    event.input.value = ""
+                    self._run_ssh_cmd(cmd)
+
+        def _connect_to_custom(self, host: str) -> None:
+            if host not in self._known_hosts:
+                self._known_hosts.insert(0, host)
+            sel = self.query_one("#unit-select", Select)
+            self._unit_switching = True
+            sel.set_options(self._select_labels(self._known_hosts))
+            sel.value = host
+            self.call_later(self._clear_switching)
+            self._do_connect(host)
+
+        def _do_connect(self, host: str) -> None:
+            if not self._connect_lock.acquire(blocking=False):
+                self._log_from_thread("warn", MSG["already_connecting"])
+                return
+            self._connect_worker(host)
+
+        @_twork(thread=True)
+        def _connect_worker(self, host: str) -> None:
+            self.call_from_thread(self._set_status, f"Connecting to {host}…")
+            try:
+                resolved = init_client(host)
+                bits = []
+                r = pi.exec("pgrep -c mixxx || true")
+                if r["stdout"].strip() not in ("", "0"):
+                    bits.append("Mixxx ◉")
+                r2 = pi.exec("ls /media/ 2>/dev/null")
+                if r2["stdout"].strip():
+                    bits.append(f"USB:{r2['stdout'].strip()}")
+                r3 = pi.exec("[ -e /dev/ttyACM0 ] && echo yes || true")
+                if "yes" in r3["stdout"]:
+                    bits.append("Pico ◉")
+                summary = "  [dim]│[/]  ".join(bits) if bits else "ready"
+                self.call_from_thread(
+                    self._set_status, f"[green]◉[/] {resolved}  [dim]│[/]  {summary}"
+                )
+                self._log_from_thread("ok", f"Connected → {resolved}")
+            except Exception as e:
+                self.call_from_thread(self._set_status, f"[red]✗[/] {host} — {e}")
+                self._log_from_thread("fail", f"{host}: {e}")
+            finally:
+                self._connect_lock.release()
+                # Re-enable on_select_changed after connect (deferred one tick)
+                self.call_from_thread(lambda: self.call_later(self._clear_switching))
+
+        @_twork(thread=True)
+        def action_discover(self) -> None:
+            self._log_from_thread("info", MSG["discovering"])
+            try:
+                units = discover_units(
+                    extra_hosts=[self._host] if self._host else None
+                )
+                if not units:
+                    self._log_from_thread("warn", MSG["no_units_found"])
+                    return
+                for host, hostname in units:
+                    self._log_from_thread("ok", f"{hostname}  ({host})")
+                options = [(f"{hostname}  ({host})", host) for host, hostname in units]
+                self.call_from_thread(self._apply_discovered_units, options)
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+
+        def _apply_discovered_units(self, options: list) -> None:
+            sel = self.query_one("#unit-select", Select)
+            current = sel.value
+            for _, h in options:
+                if h not in self._known_hosts:
+                    self._known_hosts.append(h)
+            self._unit_switching = True
+            sel.set_options(options)
+            values = [v for _, v in options]
+            sel.value = current if current in values else values[0]
+            self.call_later(self._clear_switching)
+
+        # ── Button dispatch ───────────────────────────────────────────────────
+
+        def on_button_pressed(self, event: Button.Pressed) -> None:
+            {
+                "btn-push":          self._ask_push,
+                "btn-pull":          self._ask_pull,
+                "btn-push-midi":     self._ask_push_midi,
+                "btn-pull-midi":     self._ask_pull_midi,
+                "btn-screenshot":    self.action_screenshot,
+                "btn-restart":       self.action_restart,
+                "btn-watch":         self.action_watch,
+                "btn-midi-mon":      self.action_midi_mon,
+                "btn-signal-an":     self.action_signal_an,
+                "btn-bootloader":    self._do_bootloader,
+                "btn-flash":         self._do_flash,
+                "btn-discover":      self.action_discover,
+                "btn-check":         self._do_check,
+                "btn-backup":        self._do_backup,
+                "btn-verify-backup": self._do_verify_backup,
+                "btn-ssh-keys":      self._do_ssh_keys,
+                "btn-dhcp":          self._do_dhcp,
+                "btn-help":          self._open_help,
+                "btn-about":         self._open_about,
+                "btn-settings":      self._open_settings,
+                "btn-copy-log":      self.action_copy_log,
+                "btn-copy-tail":     self.action_copy_tail,
+                "btn-clear-log":     self.action_clear_log,
+            }.get(event.button.id, lambda: None)()
+
+        # ── Confirm-modal helpers ─────────────────────────────────────────────
+
+        def _ask_push(self) -> None:
+            self.push_screen(
+                ConfirmScreen("Push skin to Pi — backup remote first?",
+                              "Push",  "push",
+                              "Backup remote then push", "backup"),
+                self._start_push,
+            )
+
+        def _start_push(self, choice: str | None) -> None:
+            if choice is None: return
+            self.action_push(backup_remote=(choice == "backup"))
+
+        def _ask_pull(self) -> None:
+            self.push_screen(
+                ConfirmScreen("Pull skin from Pi — what to do with local files?",
+                              "Replace", "replace",
+                              "Backup then replace", "backup"),
+                self._start_pull,
+            )
+
+        def _start_pull(self, choice: str | None) -> None:
+            if choice is None: return
+            self._do_pull(backup=(choice == "backup"))
+
+        def _ask_push_midi(self) -> None:
+            self.push_screen(
+                ConfirmScreen("Push MIDI to Pi — backup remote first?",
+                              "Push",  "push",
+                              "Backup remote then push", "backup"),
+                self._start_push_midi,
+            )
+
+        def _start_push_midi(self, choice: str | None) -> None:
+            if choice is None: return
+            self._do_push_midi(backup_remote=(choice == "backup"))
+
+        def _ask_pull_midi(self) -> None:
+            self.push_screen(
+                ConfirmScreen("Pull MIDI from Pi — what to do with local files?",
+                              "Replace", "replace",
+                              "Backup then replace", "backup"),
+                self._start_pull_midi,
+            )
+
+        def _start_pull_midi(self, choice: str | None) -> None:
+            if choice is None: return
+            self._do_pull_midi(backup=(choice == "backup"))
+
+        # ── Actions ───────────────────────────────────────────────────────────
+
+        @_twork(thread=True)
+        def action_push(self, backup_remote: bool = False) -> None:
+            if not self._op_start(): return
+            try:
+                label = MSG["pushing_skin_backup"] if backup_remote else MSG["pushing_skin"]
+                self._log_from_thread("head", label)
+                pushed = push_skin(backup_remote=backup_remote)
+                for p in pushed:
+                    self._log_from_thread("ok", p)
+                self._log_from_thread("ok", MSG["pushed_skin"].format(n=len(pushed)))
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _do_pull(self, backup: bool = False) -> None:
+            if not self._op_start(): return
+            try:
+                label = MSG["pulling_skin_backup"] if backup else MSG["pulling_skin"]
+                self._log_from_thread("head", label)
+                pulled = pull_skin(backup=backup)
+                for p in pulled:
+                    self._log_from_thread("ok", p)
+                self._log_from_thread("ok", MSG["pulled_skin"].format(n=len(pulled)))
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def action_screenshot(self) -> None:
+            if not self._op_start(): return
+            try:
+                self._log_from_thread("info", MSG["screenshotting"])
+                data, err = take_screenshot()
+                if err:
+                    self._log_from_thread("fail", err)
+                else:
+                    out = tmp_path("xdj_screenshot.png")
+                    out.write_bytes(data)
+                    self._log_from_thread("ok", f"Saved → {out}")
+                    open_image(out)
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def action_restart(self) -> None:
+            if not self._op_start(): return
+            try:
+                self._log_from_thread("info", MSG["restarting_mixxx"])
+                self._log_from_thread("ok", restart_mixxx())
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        def action_watch(self) -> None:
+            btn = self.query_one("#btn-watch", Button)
+            if self._watching:
+                self._watch_stop.set()
+                self._watching = False
+                btn.label = "Watch ▶"
+                btn.remove_class("-active-watch")
+            else:
+                self._watch_stop.clear()
+                self._watching = True
+                btn.label = "Watch ■"
+                btn.add_class("-active-watch")
+                self._do_watch()
+
+        @_twork(thread=True)
+        def _do_watch(self) -> None:
+            self._log_from_thread("head", MSG["watch_started"])
+            from xdj_pi_dev.watch import _REPO_SKIN as _ws
+            self._log_from_thread("info", f"Folder: {_ws}")
+            try:
+                def _watch_shot(_paths: list[str]) -> None:
+                    data, err = take_screenshot()
+                    if err:
+                        self._log_from_thread("warn", f"Screenshot: {err}")
+                        return
+                    out = tmp_path("xdj_watch_screen.png")
+                    out.write_bytes(data)
+                    open_image(out)
+                    self._log_from_thread("info", f"Screenshot → {out}")
+
+                _watch_loop(pi, self._watch_stop, self._log_from_thread, screenshot_fn=_watch_shot)
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            self.call_from_thread(self._watch_done)
+
+        def _watch_done(self) -> None:
+            self._watching = False
+            btn = self.query_one("#btn-watch", Button)
+            btn.label = "Watch ▶"
+            btn.remove_class("-active-watch")
+            self._log("info", MSG["watch_stopped"])
+
+        def action_midi_mon(self) -> None:
+            btn = self.query_one("#btn-midi-mon", Button)
+            if self._midi_mon:
+                self._midi_mon_stop.set()
+                self._midi_mon = False
+                btn.label = "MIDI Mon ▶"
+                btn.remove_class("-active-watch")
+            else:
+                self._midi_mon_stop.clear()
+                self._midi_mon = True
+                btn.label = "MIDI Mon ■"
+                btn.add_class("-active-watch")
+                self._do_midi_mon()
+
+        @_twork(thread=True)
+        def _do_midi_mon(self) -> None:
+            try:
+                midi_monitor(pi, self._midi_mon_stop, self._log_from_thread)
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            self.call_from_thread(self._midi_mon_done)
+
+        def _midi_mon_done(self) -> None:
+            self._midi_mon = False
+            btn = self.query_one("#btn-midi-mon", Button)
+            btn.label = "MIDI Mon ▶"
+            btn.remove_class("-active-watch")
+            self._log("info", "MIDI monitor stopped")
+
+        def action_signal_an(self) -> None:
+            import socket as _sock, webbrowser
+            if self._signal_an:
+                self._signal_an_stop.set()
+                self._signal_an = False
+                btn = self.query_one("#btn-signal-an", Button)
+                btn.label = "Signal An ▶"
+                btn.remove_class("-active-watch")
+                return
+            with _sock.socket() as s:
+                s.bind(("", 0))
+                port = s.getsockname()[1]
+            self._signal_an_stop = threading.Event()
+            self._signal_an = True
+            btn = self.query_one("#btn-signal-an", Button)
+            btn.label = "Signal An ■"
+            btn.add_class("-active-watch")
+            url = f"http://localhost:{port}/"
+            self._log("info", f"Signal Analyzer → {url}")
+            threading.Thread(
+                target=run_signal_analyzer_web,
+                args=(pi, self._signal_an_stop, port),
+                daemon=True,
+            ).start()
+            self.call_later(lambda: webbrowser.open(url))
+
+        @_twork(thread=True)
+        def _do_push_midi(self, backup_remote: bool = False) -> None:
+            if not self._op_start(): return
+            try:
+                label = MSG["pushing_midi_backup"] if backup_remote else MSG["pushing_midi"]
+                self._log_from_thread("head", label)
+                pushed = push_midi(backup_remote=backup_remote)
+                for p in pushed:
+                    self._log_from_thread("ok", p)
+                self._log_from_thread("ok", MSG["midi_reload"])
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _do_pull_midi(self, backup: bool = False) -> None:
+            if not self._op_start(): return
+            try:
+                label = MSG["pulling_midi_backup"] if backup else MSG["pulling_midi"]
+                self._log_from_thread("head", label)
+                pulled = pull_midi(backup=backup)
+                for p in pulled:
+                    self._log_from_thread("ok", p)
+                self._log_from_thread("ok", MSG["pulled_midi"].format(n=len(pulled)))
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _do_bootloader(self) -> None:
+            # MIDI monitor holds the Pi ALSA port — release it before sending the bootloader signal
+            if self._midi_mon:
+                self._midi_mon_stop.set()
+                self._log_from_thread("info", "Stopping MIDI monitor (needed for bootloader)…")
+                time.sleep(0.8)
+                self.call_from_thread(self._midi_mon_done)
+            if not self._op_start(): return
+            try:
+                self._log_from_thread("head", MSG["pico_boot_starting"])
+                msg = pico_bootloader(pi)
+                level = "ok" if "update mode" in msg else ("warn" if "signal sent" in msg else "fail")
+                self._log_from_thread(level, msg)
+            except Exception as e:
+                self._log_from_thread("fail", str(e) or f"{type(e).__name__}")
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _do_flash(self) -> None:
+            if not self._op_start(): return
+            try:
+                from xdj_pi_dev.config import get_firmware_dir
+                try:
+                    fw_dir = get_firmware_dir()
+                except RuntimeError as e:
+                    self._log_from_thread("warn", str(e))
+                    return
+                candidates = sorted(
+                    fw_dir.glob("*.uf2"),
+                    key=lambda p: p.stat().st_mtime, reverse=True,
+                )
+                if not candidates:
+                    self._log_from_thread("fail", MSG["flash_fail_nofile"])
+                    return
+                uf2 = candidates[0]
+                self._log_from_thread("head", MSG["flashing"])
+                msg = pico_flash(pi, str(uf2))
+                is_fail = any(w in msg.lower() for w in (
+                    "couldn't", "failed", "not found", "cp_failed", "error", "unexpected",
+                ))
+                self._log_from_thread("fail" if is_fail else "ok", msg or "No output from flash command")
+            except Exception as e:
+                self._log_from_thread("fail", repr(e) if not str(e) else str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _do_ssh_keys(self) -> None:
+            if not self._op_start(): return
+            try:
+                self._log_from_thread("head", MSG["ssh_keys_starting"])
+                setup_ssh_keys(pi)
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _do_dhcp(self) -> None:
+            if not self._op_start(): return
+            try:
+                self._log_from_thread("head", MSG["dhcp_starting"])
+                setup_pi_dhcp(pi)
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _run_ssh_cmd(self, cmd: str) -> None:
+            if pi is None:
+                self._log_from_thread("warn", MSG["not_connected"])
+                return
+            self._log_from_thread("info", f"$ {cmd}")
+            try:
+                r = pi.exec(cmd, timeout=60)
+                for line in (r["stdout"] or "").splitlines():
+                    self._log_from_thread("info", line)
+                for line in (r["stderr"] or "").splitlines():
+                    self._log_from_thread("warn", line)
+                if r["rc"] != 0:
+                    self._log_from_thread("info", f"[exit {r['rc']}]")
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+
+        def _apply_board_visibility(self) -> None:
+            """Show/hide PICO-specific sidebar items based on current board config."""
+            pico = is_pico_board()
+            for wid in ("btn-signal-an", "lbl-pico", "btn-bootloader", "btn-flash"):
+                try:
+                    self.query_one(f"#{wid}").display = pico
+                except Exception:
+                    pass
+
+        def _open_help(self) -> None:
+            self.push_screen(HelpScreen())
+
+        def _open_about(self) -> None:
+            self.push_screen(AboutScreen())
+
+        def _open_settings(self) -> None:
+            self.push_screen(SettingsScreen(), self._on_settings_saved)
+
+        def _on_settings_saved(self, chosen: str | None) -> None:
+            if chosen is None:
+                return
+            self._log("ok", f"Settings saved — board: {_BOARD_META.get(chosen, (chosen,))[0]}")
+            self._apply_board_visibility()
+
+        def action_copy_log(self) -> None:
+            text = "\n".join(self._log_lines)
+            try:
+                if sys.platform == "darwin":
+                    subprocess.run(["pbcopy"], input=text.encode(), check=True)
+                elif shutil.which("xclip"):
+                    subprocess.run(["xclip", "-selection", "clipboard"],
+                                   input=text.encode(), check=True)
+                elif shutil.which("xsel"):
+                    subprocess.run(["xsel", "--clipboard", "--input"],
+                                   input=text.encode(), check=True)
+                else:
+                    self._log("warn", "No clipboard tool found (pbcopy/xclip/xsel)")
+                    return
+                self._log("ok", f"Log copied to clipboard ({len(self._log_lines)} lines)")
+            except Exception as e:
+                self._log("fail", f"Copy failed: {e}")
+
+        def action_clear_log(self) -> None:
+            self._log_lines.clear()
+            self.query_one("#log", RichLog).clear()
+            self.query_one("#log", RichLog).write("[dim]── log cleared ──[/]")
+
+        def action_copy_tail(self) -> None:
+            """Copy last 30 log lines to clipboard — useful for grabbing recent output."""
+            tail = self._log_lines[-30:]
+            text = "\n".join(tail)
+            try:
+                if sys.platform == "darwin":
+                    subprocess.run(["pbcopy"], input=text.encode(), check=True)
+                elif shutil.which("xclip"):
+                    subprocess.run(["xclip", "-selection", "clipboard"],
+                                   input=text.encode(), check=True)
+                elif shutil.which("xsel"):
+                    subprocess.run(["xsel", "--clipboard", "--input"],
+                                   input=text.encode(), check=True)
+                else:
+                    self._log("warn", "No clipboard tool found (pbcopy/xclip/xsel)")
+                    return
+                self._log("ok", f"Last {len(tail)} lines copied to clipboard")
+            except Exception as e:
+                self._log("fail", f"Copy failed: {e}")
+
+        @_twork(thread=True)
+        def _do_check(self) -> None:
+            if not self._op_start(): return
+            try:
+                self._log_from_thread("head", MSG["preflight_start"])
+                run_check(self._host)
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _do_backup(self) -> None:
+            if not self._op_start(): return
+            try:
+                self._log_from_thread("head", MSG["backup_starting"])
+                self._log_from_thread("warn", MSG["backup_wait"])
+                out_path = backup_pi_image(pi, log_fn=self._log_from_thread)
+                if out_path:
+                    self._log_from_thread("ok", f"Backup saved → {out_path}")
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+        @_twork(thread=True)
+        def _do_verify_backup(self) -> None:
+            if not self._op_start(): return
+            # Ask user to provide the file path via the log (TUI can't open file dialogs)
+            # Find the most recent backup in the repo directory
+            import glob as _glob
+            pattern = str(Path(__file__).parent.parent / "xdj-pi-backup-*.tar")
+            matches = sorted(_glob.glob(pattern))
+            if not matches:
+                self._log_from_thread("warn", "No xdj-pi-backup-*.tar found in repo root")
+                self._log_from_thread("info", "Run:  python3 tools/xdj-pi-dev.py --verify-backup <file.tar>")
+                self._op_end()
+                return
+            latest = matches[-1]
+            try:
+                self._log_from_thread("head", f"Verifying {Path(latest).name}…")
+                verify_backup(pi, latest)
+                self._log_from_thread("ok", "Verification complete — check terminal for details")
+            except Exception as e:
+                self._log_from_thread("fail", str(e))
+            finally:
+                self._op_end()
+
+
+def main() -> None:
+    global PI_USER, PI_PASS, pi
+
+    ap = argparse.ArgumentParser(
+        description="XDJ Pi developer tool — CLI + MCP server for Claude Code",
+        formatter_class=argparse.RawDescriptionHelpFormatter,
+        epilog=__doc__,
+    )
+
+    # Connection
+    conn = ap.add_argument_group("connection")
+    conn.add_argument("--host",     metavar="HOST",
+                      help="Pi IP or hostname (overrides XDJ_HOST env)")
+    conn.add_argument("--user",     metavar="USER",    default=PI_USER,
+                      help=f"SSH username (default: {PI_USER})")
+    conn.add_argument("--password", metavar="PASS",    default=PI_PASS,
+                      help="SSH password (default: built-in or XDJ_PASS env)")
+
+    # Setup
+    setup = ap.add_argument_group("setup (run these first)")
+    setup.add_argument("--check",          action="store_true",
+                       help="Pre-flight: check deps, connection, Mixxx, audio")
+    setup.add_argument("--discover",       action="store_true",
+                       help="Scan network for Pi units")
+    setup.add_argument("--setup-pi-dhcp", action="store_true",
+                       help="Configure Pi as DHCP server — no manual IP config ever again")
+    setup.add_argument("--setup-ssh-keys", action="store_true",
+                       help="Generate key pair and install on Pi (passwordless auth)")
+    setup.add_argument("--restore-ssh",   action="store_true",
+                       help="Print SSH recovery guide (no connection required)")
+    setup.add_argument("--set-hostname",  metavar="NAME",
+                       help="Rename Pi (e.g. xdj-unit2 for multi-unit setups)")
+    setup.add_argument("--backup-image",  metavar="FILE", nargs="?", const="",
+                       help="Backup Pi SD card to a .tar archive (used blocks only, default: cwd)")
+    setup.add_argument("--verify-backup", metavar="FILE",
+                       help="Verify a backup .tar: test gzip integrity + compare manifest against live Pi")
+
+    # Skin dev
+    skin = ap.add_argument_group("skin development")
+    skin.add_argument("--status",       action="store_true",  help="Pi + Mixxx live status")
+    skin.add_argument("--screenshot",   action="store_true",  help="Capture Pi display")
+    skin.add_argument("--panel",        metavar="PANEL",
+                      help="Panel to show (hotcue/hc, beatloop/bl, keyshift/ks, beatjump/bj, stems/st)")
+    skin.add_argument("--restart",      action="store_true",  help="Restart Mixxx")
+    skin.add_argument("--push",         metavar="GLOB", nargs="?", const="*",
+                      help="Push skin files to Pi (default: all)")
+    skin.add_argument("--push-midi",    action="store_true",
+                      help="Push MIDI mapping files (docs/midi/) to Pi controllers dir")
+    skin.add_argument("--pull-midi",    action="store_true",
+                      help="Pull MIDI mapping files from Pi to local midi dir")
+    skin.add_argument("--midi-mon",     action="store_true",
+                      help="Stream live MIDI messages from controller (Ctrl-C to stop)")
+    skin.add_argument("--pull",         action="store_true",  help="Pull skin from Pi to repo")
+    skin.add_argument("--watch",        action="store_true",
+                      help="Watch skin dir, auto-push + screenshot on change")
+    skin.add_argument("--full-restart", action="store_true",
+                      help="Full Mixxx restart in watch mode (default: try Ctrl+F5)")
+
+    # Pico / firmware
+    pico = ap.add_argument_group("firmware")
+    pico.add_argument("--setup-pico-cli",  action="store_true",
+                      help="Install arduino-cli + RP2040 toolchain on Pi (one-time, needs Pi internet)")
+    pico.add_argument("--pico-compile",    action="store_true",
+                      help="Compile firmware (local arduino-cli first, falls back to Pi)")
+    pico.add_argument("--pico-bootloader", action="store_true",
+                      help="Trigger UF2 bootloader on Pico via MIDI (or combined with --pico-compile to compile+flash)")
+    pico.add_argument("--pico-flash",      metavar="FILE",
+                      help="Flash a local .uf2/.hex file to Pico via Pi")
+    pico.add_argument("--board",           metavar="BOARD", default=DEFAULT_BOARD,
+                      help=(
+                          f"Board profile or raw FQBN (default: {DEFAULT_BOARD}). "
+                          f"Profiles: {', '.join(BOARD_PROFILES)}"
+                      ))
+    pico.add_argument("--analyze",         action="store_true",
+                      help="Live GPIO signal analyzer — curses dashboard reading Pico Core 1 via /dev/ttyACM0")
+
+    # Other
+    ap.add_argument("--cmd",   metavar="CMD", help="Run arbitrary SSH command on Pi")
+    ap.add_argument("--ui",   action="store_true", help="Open interactive TUI (requires: pip install textual)")
+    ap.add_argument("--about", action="store_true", help="Show authors and credits")
+
+    args = ap.parse_args()
+
+    # Apply CLI credential overrides
+    PI_USER = args.user
+    PI_PASS = args.password
+
+    # TUI — launches before any connection (app handles it internally)
+    if args.about:
+        print(_TOOL_ABOUT)
+        return
+
+    if args.ui:
+        if not _TEXTUAL:
+            print("textual not installed. Run:  pip install textual")
+            sys.exit(1)
+        XDJApp(host=args.host).run()
+        return
+
+    # Commands that need no Pi connection
+    if args.restore_ssh:
+        restore_ssh()
+        return
+
+    if args.discover:
+        units = discover_units(extra_hosts=[args.host] if args.host else None)
+        if units:
+            print(f"\nFound {len(units)} Pi unit(s):\n")
+            for host, hostname in units:
+                print(f"  {host:<20}  hostname: {hostname}")
+            print(f"\nConnect:  python3 xdj-pi-dev.py --host {units[0][0]} --status")
+        else:
+            print("No Pi units found.")
+        return
+
+    # Pre-flight check (resolves connection internally)
+    if args.check:
+        run_check(args.host)
+        return
+
+    # All remaining commands need a live Pi connection
+    try:
+        host = init_client(args.host)
+    except ConnectionError as e:
+        print(f"\n{e}")
+        sys.exit(1)
+
+    if args.status:
+        cli_status()
+
+    elif args.setup_pi_dhcp:
+        setup_pi_dhcp(pi)
+
+    elif args.setup_ssh_keys:
+        setup_ssh_keys(pi)
+
+    elif args.set_hostname:
+        set_hostname(pi, args.set_hostname)
+
+    elif args.backup_image is not None:
+        backup_pi_image(pi, args.backup_image or None)
+
+    elif args.verify_backup:
+        verify_backup(pi, args.verify_backup)
+
+    elif args.screenshot:
+        data, err = take_screenshot(panel=args.panel)
+        if err:
+            print(f"Failed: {err}")
+        else:
+            out = tmp_path("xdj_screenshot.png")
+            out.write_bytes(data)
+            print(f"Saved: {out}")
+            open_image(out)
+
+    elif args.restart:
+        print(restart_mixxx(panel=args.panel))
+
+    elif args.push is not None:
+        pushed = push_skin(args.push)
+        for p in pushed:
+            print(f"  ✓ {p}")
+        print(f"Done: {len(pushed)} file(s)")
+
+    elif args.push_midi:
+        pushed = push_midi()
+        for p in pushed:
+            ok(p)
+        print(f"\n  Pushed {len(pushed)} MIDI file(s) → {PI_MIDI_DIR}")
+        print(f"  {_C.DIM}In Mixxx: Preferences → Controllers → disable + re-enable mapping{_C.RESET}")
+
+    elif args.pull_midi:
+        pulled = pull_midi()
+        for p in pulled:
+            print(f"  ✓ {p}")
+        print(f"Done: {len(pulled)} MIDI file(s)")
+
+    elif args.midi_mon:
+        stop = threading.Event()
+        try:
+            midi_monitor(pi, stop, lambda t, m: print(f"[{t}] {m}"))
+        except KeyboardInterrupt:
+            stop.set()
+
+    elif args.pull:
+        pulled = pull_skin()
+        for p in pulled:
+            print(f"  ✓ {p}")
+        print(f"Done: {len(pulled)} file(s)")
+
+    elif args.watch:
+        watch_mode(pi, panel=args.panel, restart=args.full_restart)
+
+    elif args.setup_pico_cli:
+        setup_pico_cli(pi)
+
+    elif args.pico_compile:
+        pico_compile(pi, flash=args.pico_bootloader, board=args.board)
+
+    elif args.pico_bootloader:
+        print(pico_bootloader(pi))
+
+    elif args.pico_flash:
+        print(pico_flash(pi, args.pico_flash))
+
+    elif args.analyze:
+        run_signal_analyzer_cli(pi)
+
+    elif args.cmd:
+        r = pi.exec(args.cmd)
+        if r["stdout"]: sys.stdout.write(r["stdout"])
+        if r["stderr"]: sys.stderr.write(r["stderr"])
+        sys.exit(r["rc"])
+
+    else:
+        # No CLI flag → MCP server mode
+        env = os.environ.get("XDJ_HOST")
+        candidates = [args.host] if args.host else ([env] if env else _DEFAULT_HOSTS)
+        resolved = resolve_host(candidates)
+        if resolved:
+            pi = PiClient(resolved, PI_USER, PI_PASS)
+        run_mcp_server()
+
+
+if __name__ == "__main__":
+    main()
diff --git a/tools/xdj_pi_dev/__init__.py b/tools/xdj_pi_dev/__init__.py
new file mode 100644
index 0000000..27dd4c3
--- /dev/null
+++ b/tools/xdj_pi_dev/__init__.py
@@ -0,0 +1 @@
+# xdj_pi_dev — XDJ-100SX Pi Developer Tool modules
diff --git a/tools/xdj_pi_dev/_terminal.py b/tools/xdj_pi_dev/_terminal.py
new file mode 100644
index 0000000..1472787
--- /dev/null
+++ b/tools/xdj_pi_dev/_terminal.py
@@ -0,0 +1,158 @@
+from __future__ import annotations
+
+"""
+Shared terminal UI helpers.
+
+Extracted from xdj-pi-dev.py so all sub-modules can import consistent
+colour, spinner, and logging primitives without circular dependencies.
+"""
+
+import itertools
+import shutil
+import sys
+import threading
+from typing import Any
+
+
+# ─── ANSI colour ─────────────────────────────────────────────────────────────
+
+def _ansi_enable() -> bool:
+    """Enable ANSI on Windows; return True if terminal supports colour."""
+    if not sys.stdout.isatty():
+        return False
+    if sys.platform == "win32":
+        try:
+            import ctypes
+            k = ctypes.windll.kernel32
+            k.SetConsoleMode(k.GetStdHandle(-11), 7)
+        except Exception:
+            return False
+    return True
+
+
+_COLOR = _ansi_enable()
+
+
+class _C:
+    RESET  = "\033[0m"   if _COLOR else ""
+    BOLD   = "\033[1m"   if _COLOR else ""
+    DIM    = "\033[2m"   if _COLOR else ""
+    GREEN  = "\033[32m"  if _COLOR else ""
+    YELLOW = "\033[33m"  if _COLOR else ""
+    RED    = "\033[31m"  if _COLOR else ""
+    CYAN   = "\033[36m"  if _COLOR else ""
+    GRAY   = "\033[90m"  if _COLOR else ""
+    ERASE  = "\r\033[K"  if _COLOR else "\r"
+
+
+_SPIN_FRAMES = "⠋⠙⠹⠸⠼⠴⠦⠧⠇⠏"
+
+
+# ─── Spinner step ─────────────────────────────────────────────────────────────
+
+class Step:
+    """
+    Context manager for a named operation with a live spinner.
+
+        with Step("Stopping Mixxx"):
+            pi_client.exec("killall mixxx")
+
+    Prints  ⠹  Stopping Mixxx...   while running,
+    then    ✓  Stopping Mixxx       on success,
+    or      ✗  Stopping Mixxx       on exception.
+    """
+
+    def __init__(self, label: str, indent: int = 2) -> None:
+        self.label  = label
+        self.indent = " " * indent
+        self._stop  = threading.Event()
+        self._thread: threading.Thread | None = None
+
+    def __enter__(self) -> "Step":
+        self._stop.clear()
+        self._thread = threading.Thread(target=self._spin, daemon=True)
+        self._thread.start()
+        return self
+
+    def _spin(self) -> None:
+        for frame in itertools.cycle(_SPIN_FRAMES):
+            sys.stdout.write(
+                f"{_C.ERASE}{self.indent}{_C.CYAN}{frame}{_C.RESET}"
+                f"  {self.label}…"
+            )
+            sys.stdout.flush()
+            if self._stop.wait(0.08):
+                break
+
+    def __exit__(self, exc_type, exc_val, exc_tb) -> None:
+        self._stop.set()
+        if self._thread:
+            self._thread.join()
+        if exc_type is None:
+            sys.stdout.write(
+                f"{_C.ERASE}{self.indent}{_C.GREEN}✓{_C.RESET}"
+                f"  {self.label}\n"
+            )
+        else:
+            sys.stdout.write(
+                f"{_C.ERASE}{self.indent}{_C.RED}✗{_C.RESET}"
+                f"  {self.label}  {_C.DIM}({exc_val}){_C.RESET}\n"
+            )
+        sys.stdout.flush()
+        return False  # don't suppress exceptions
+
+
+# ─── Log routing ──────────────────────────────────────────────────────────────
+
+# Set by XDJApp when TUI is active; (level, msg) -> None  where level in ok/warn/fail/info/head
+_tui_log_fn: Any = None
+
+
+def section(title: str) -> None:
+    if _tui_log_fn:
+        _tui_log_fn("head", title)
+        return
+    w = shutil.get_terminal_size((72, 24)).columns
+    bar = "─" * min(w, 72)
+    print(f"\n{_C.BOLD}{bar}{_C.RESET}")
+    print(f"  {_C.BOLD}{title}{_C.RESET}")
+    print(f"{_C.BOLD}{bar}{_C.RESET}")
+
+
+def ok(msg: str) -> None:
+    if _tui_log_fn:
+        _tui_log_fn("ok", msg)
+        return
+    print(f"  {_C.GREEN}✓{_C.RESET}  {msg}")
+
+
+def warn(msg: str) -> None:
+    if _tui_log_fn:
+        _tui_log_fn("warn", msg)
+        return
+    print(f"  {_C.YELLOW}⚠{_C.RESET}  {msg}")
+
+
+def fail(msg: str) -> None:
+    if _tui_log_fn:
+        _tui_log_fn("fail", msg)
+        return
+    print(f"  {_C.RED}✗{_C.RESET}  {msg}")
+
+
+def _log_line(line: str) -> None:
+    lo = line.lower()
+    if _tui_log_fn:
+        if any(x in lo for x in ("error:", "fatal error:", " error ")):
+            _tui_log_fn("fail", line)
+        elif "warning:" in lo:
+            _tui_log_fn("warn", line)
+        elif line.strip():
+            _tui_log_fn("info", line)
+        return
+    if any(x in lo for x in ("error:", "fatal error:", " error ")):
+        print(f"  {_C.RED}│{_C.RESET} {_C.RED}{line}{_C.RESET}")
+    elif "warning:" in lo:
+        print(f"  {_C.YELLOW}│{_C.RESET} {_C.YELLOW}{line}{_C.RESET}")
+    elif line.strip():
+        print(f"  {_C.GRAY}│{_C.RESET} {line}")
diff --git a/tools/xdj_pi_dev/backup.py b/tools/xdj_pi_dev/backup.py
new file mode 100644
index 0000000..bda1702
--- /dev/null
+++ b/tools/xdj_pi_dev/backup.py
@@ -0,0 +1,449 @@
+from __future__ import annotations
+
+"""
+Pi image backup: manifest collection, archive verification, and full SD-card backup.
+
+Extracted from xdj-pi-dev.py (lines 1289-1704).
+"""
+
+import sys
+import tarfile
+import tempfile
+import time
+from pathlib import Path
+
+import os
+
+from xdj_pi_dev._terminal import (
+    _C, Step, section, ok, warn, fail,
+)
+
+_PI_USER = os.environ.get("XDJ_USER", "xdj100sx")
+_H       = f"/home/{_PI_USER}"
+
+# ─── Config files tracked by the manifest ────────────────────────────────────
+
+_MANIFEST_FILES = [
+    # Network
+    "/etc/hostname", "/etc/hosts", "/etc/dhcpcd.conf",
+    "/etc/network/interfaces", "/etc/resolv.conf",
+    "/etc/dnsmasq.conf",
+    # SSH
+    f"/etc/ssh/sshd_config", f"{_H}/.ssh/authorized_keys",
+    # Boot / kernel
+    "/boot/config.txt", "/boot/cmdline.txt",
+    # System services
+    "/etc/rc.local",
+    # USB automount (dev tool)
+    "/usr/local/bin/usb-mount", "/usr/local/bin/usb-unmount",
+    "/etc/udev/rules.d/99-usb-automount.rules",
+    # Mixxx
+    f"{_H}/.mixxx/mixxx.cfg",
+    # User shell
+    f"{_H}/.bashrc", f"{_H}/.profile",
+]
+_MANIFEST_DIRS = [
+    f"{_H}/.mixxx/controllers",         # MIDI mappings
+    "/etc/dnsmasq.d",                   # dnsmasq includes
+    "/etc/systemd/system",              # custom services
+    "/usr/local/bin",                   # custom scripts
+    "/etc/udev/rules.d",                # udev rules
+]
+
+
+# ─── Manifest collection ──────────────────────────────────────────────────────
+
+def _backup_manifest(pi_client) -> bytes:
+    """SSH to Pi and collect sha256 checksums + directory listings of critical configs."""
+    import datetime as _dt
+    lines = [
+        f"# XDJ Pi backup manifest — {_dt.datetime.now().isoformat(timespec='seconds')}",
+        "# sha256sum of critical config files",
+        "# Use --verify-backup <file.tar> to check integrity and compare against live Pi",
+        "",
+    ]
+    # Checksum individual files
+    files_arg = " ".join(f'"{f}"' for f in _MANIFEST_FILES)
+    r = pi_client.exec(f"sha256sum {files_arg} 2>/dev/null || true")
+    lines += r["stdout"].splitlines()
+
+    # Checksum everything under key directories
+    for d in _MANIFEST_DIRS:
+        r2 = pi_client.exec(
+            f'find {d} -type f 2>/dev/null | sort | xargs sha256sum 2>/dev/null || true'
+        )
+        if r2["stdout"].strip():
+            lines += r2["stdout"].splitlines()
+
+    # Installed package list (snapshot, not checksums)
+    lines += ["", "# Installed packages (dpkg --get-selections)"]
+    r3 = pi_client.exec("dpkg --get-selections 2>/dev/null | grep -v deinstall || true")
+    lines += r3["stdout"].splitlines()
+
+    return ("\n".join(lines) + "\n").encode()
+
+
+# ─── Archive verification ─────────────────────────────────────────────────────
+
+def verify_backup(pi_client, path: str) -> None:
+    """Verify a backup .tar archive: test gzip integrity and display manifest."""
+    import gzip as _gzip
+    import io as _io
+
+    section("Backup Verification")
+    tfile = Path(path)
+    if not tfile.exists():
+        fail(f"File not found: {tfile}")
+        return
+
+    ok(f"Archive: {tfile}  ({tfile.stat().st_size / 1024**2:.0f} MB)")
+    print()
+
+    with Step("Opening archive"):
+        try:
+            tf = tarfile.open(tfile, "r")
+        except Exception as e:
+            raise RuntimeError(f"Cannot open tar: {e}")
+
+    members = {m.name: m for m in tf.getmembers()}
+    expected = {"mbr.bin.gz", "sfdisk.dump", "p1-boot.vfat.gz", "restore.sh"}
+
+    ok(f"Members: {', '.join(sorted(members))}")
+    missing = expected - set(members)
+    if missing:
+        warn(f"Unexpected missing members: {missing}")
+
+    # Test gzip integrity of compressed parts
+    gz_parts = [n for n in members if n.endswith(".gz")]
+    for name in sorted(gz_parts):
+        with Step(f"gzip -t  {name}"):
+            data = tf.extractfile(members[name])
+            if data is None:
+                raise RuntimeError(f"Cannot read {name} from archive (directory entry?)")
+            raw = data.read()
+            try:
+                with _gzip.open(_io.BytesIO(raw)) as gz:
+                    gz.read()
+            except OSError as _e:
+                raise RuntimeError(f"Corrupt: {name}  ({_e})")
+        ok(f"{name}  {len(raw) / 1024**2:.1f} MB  ✓")
+
+    # Show sfdisk partition layout
+    if "sfdisk.dump" in members:
+        layout_data = tf.extractfile(members["sfdisk.dump"])
+        if layout_data:
+            print()
+            ok("Partition layout:")
+            for line in layout_data.read().decode().splitlines():
+                if line.strip() and not line.startswith("#"):
+                    print(f"    {line}")
+
+    # Show manifest
+    if "manifest.txt" in members:
+        mdata = tf.extractfile(members["manifest.txt"])
+        if mdata:
+            manifest_lines = mdata.read().decode().splitlines()
+            print()
+            ok("Manifest (critical config checksums):")
+            for line in manifest_lines:
+                if line.startswith("#") or not line.strip():
+                    print(f"  {_C.DIM}{line}{_C.RESET}")
+                else:
+                    print(f"  {line}")
+
+            # If Pi is reachable, compare live checksums
+            if pi_client._ssh:
+                print()
+                with Step("Comparing manifest against live Pi"):
+                    live_checksums: dict[str, str] = {}
+                    saved_checksums: dict[str, str] = {}
+                    for line in manifest_lines:
+                        if line.startswith("#") or "  " not in line:
+                            continue
+                        parts = line.split("  ", 1)
+                        if len(parts) == 2:
+                            saved_checksums[parts[1].strip()] = parts[0].strip()
+
+                    all_files = list(saved_checksums.keys())
+                    if all_files:
+                        files_arg = " ".join(f'"{f}"' for f in all_files[:100])
+                        r_live = pi_client.exec(f"sha256sum {files_arg} 2>/dev/null || true")
+                        for line in r_live["stdout"].splitlines():
+                            if "  " in line:
+                                ck, fp = line.split("  ", 1)
+                                live_checksums[fp.strip()] = ck.strip()
+
+                print()
+                changed, missing_live, ok_count = [], [], 0
+                for fp, saved_ck in saved_checksums.items():
+                    if fp not in live_checksums:
+                        missing_live.append(fp)
+                    elif live_checksums[fp] != saved_ck:
+                        changed.append(fp)
+                    else:
+                        ok_count += 1
+
+                ok(f"{ok_count} files match backup exactly")
+                if changed:
+                    warn(f"{len(changed)} files changed since backup:")
+                    for f in changed:
+                        print(f"    {_C.YELLOW}CHANGED{_C.RESET}  {f}")
+                if missing_live:
+                    warn(f"{len(missing_live)} files from backup not found on live Pi:")
+                    for f in missing_live:
+                        print(f"    {_C.RED}MISSING{_C.RESET}  {f}")
+                if not changed and not missing_live:
+                    ok("All config files on Pi match the backup — backup is current")
+    else:
+        warn("No manifest.txt in archive (backup created before verification was added)")
+
+    tf.close()
+    print()
+    ok("Verification complete")
+
+
+# ─── Full SD-card image backup ────────────────────────────────────────────────
+
+def backup_pi_image(pi_client, output_path: str | None = None, log_fn=None) -> str | None:
+    """Back up the Pi SD card using only used filesystem blocks.
+
+    Creates a .tar archive containing:
+      mbr.bin.gz      — first 1 MiB of disk (MBR + partition table bootstrap code)
+      sfdisk.dump     — partition layout (sfdisk text format)
+      p1-boot.vfat.gz — FAT32 boot partition (~256 MB, full)
+      p2-root.img.gz  — root partition: e2image -r if available (reads used blocks only),
+                        otherwise sequential dd (empty space compresses away with gzip)
+      restore.sh      — restoration script
+
+    Sequential block reads keep SD card at full speed (~20-40 MB/s).
+    tar is NOT used — it causes random seeks which drop SD throughput to ~1-3 MB/s.
+
+    Restore on a fresh card (Linux):
+        tar xf backup.tar
+        sudo bash restore.sh /dev/sdX        # or /dev/mmcblkX for a card reader
+    """
+    import datetime
+
+    section("Pi Image Backup")
+
+    # ── Detect disk ──────────────────────────────────────────────────────────
+    with Step("Detecting SD card"):
+        r = pi_client.exec(
+            "test -b /dev/mmcblk0 && echo mmcblk0 || "
+            "lsblk -ndo NAME,TYPE,TRAN 2>/dev/null | "
+            "awk '$2==\"disk\" && $3!=\"usb\"{print $1}' | head -1"
+        )
+        disk = r["stdout"].strip()
+        if not disk:
+            raise RuntimeError("No suitable disk device found on Pi")
+        disk_dev = f"/dev/{disk}"
+        boot_dev = f"{disk_dev}p1"
+        root_dev = f"{disk_dev}p2"
+
+    ok(f"Disk: {disk_dev}   Boot: {boot_dev}   Root: {root_dev}")
+
+    # ── Report sizes ─────────────────────────────────────────────────────────
+    r_used = pi_client.exec(
+        f"df -BM --output=used {root_dev} 2>/dev/null | tail -1 | tr -d ' M' || echo 0"
+    )
+    r_disk = pi_client.exec(f"sudo blockdev --getsize64 {disk_dev} 2>/dev/null || echo 0")
+    disk_gb = int(r_disk["stdout"].strip() or 0) / 1024**3
+    used_mb = int(r_used["stdout"].strip() or 0)
+    if disk_gb:
+        ok(f"Disk: {disk_gb:.1f} GB total,  root used: ~{used_mb} MB  (archive size ~ used data)")
+
+    # ── Get partition table ───────────────────────────────────────────────────
+    r_sfdisk = pi_client.exec(f"sudo sfdisk --dump {disk_dev} 2>/dev/null || echo ''")
+    sfdisk_dump = r_sfdisk["stdout"].encode()
+
+    # ── Output path ───────────────────────────────────────────────────────────
+    if not output_path:
+        ts = datetime.datetime.now().strftime("%Y%m%d-%H%M%S")
+        output_path = str(Path.cwd() / f"xdj-pi-backup-{ts}.tar")
+    out = Path(output_path)
+    if out.suffix != ".tar":
+        out = out.with_suffix(".tar")
+
+    warn(f"Output: {out}")
+    warn("Root is archived via tar (used files only) — no extra tools needed on Pi")
+    print()
+
+    # ── Streaming helper ──────────────────────────────────────────────────────
+    def _stream(label: str, cmd: str, dest: Path) -> int:
+        transport = pi_client._ssh.get_transport()
+        assert transport
+        ch = transport.open_session()
+        ch.exec_command(cmd)
+        received = 0
+        cancelled = False
+        last_log = 0.0
+        try:
+            with open(dest, "wb") as fout:
+                while True:
+                    if ch.recv_ready():
+                        chunk = ch.recv(131072)
+                        if not chunk:
+                            break
+                        fout.write(chunk)
+                        received += len(chunk)
+                        if log_fn:
+                            now = time.monotonic()
+                            if now - last_log >= 3.0:
+                                log_fn("info", f"{label}: {received / 1024**2:.0f} MB received…")
+                                last_log = now
+                        else:
+                            sys.stdout.write(
+                                f"\r  {_C.CYAN}↓{_C.RESET}  {label:<36}  {received / 1024**2:6.1f} MB"
+                            )
+                            sys.stdout.flush()
+                    elif ch.exit_status_ready() and not ch.recv_ready():
+                        break
+                    else:
+                        time.sleep(0.05)
+        except KeyboardInterrupt:
+            cancelled = True
+        finally:
+            ch.close()
+        if cancelled:
+            raise KeyboardInterrupt
+        done_msg = f"{label}: done — {received / 1024**2:.0f} MB"
+        if log_fn:
+            log_fn("ok", done_msg)
+        else:
+            print(f"\r  {_C.GREEN}✓{_C.RESET}  {label:<36}  {received / 1024**2:.1f} MB")
+        return received
+
+    # ── Choose fastest available compressor ──────────────────────────────────
+    # pigz = parallel gzip (uses all cores); fall back to gzip -1 (fast, single-core).
+    # Both beat the default gzip -6 by 2-4x on a Pi 4.
+    r_pigz = pi_client.exec("which pigz 2>/dev/null || echo ''")
+    if r_pigz["stdout"].strip():
+        GZIP = "pigz -1"
+        ok("Compressor: pigz -1 (parallel gzip)")
+    else:
+        GZIP = "gzip -1"
+        ok("Compressor: gzip -1 (fast mode; install pigz on Pi for extra speed)")
+
+    # ── Stop Mixxx to free CPU during compression ─────────────────────────────
+    mixxx_was_running = False
+    r_mx = pi_client.exec("pgrep -x mixxx || echo ''")
+    if r_mx["stdout"].strip():
+        mixxx_was_running = True
+        pi_client.exec("sudo pkill -x mixxx 2>/dev/null || true")
+        if log_fn:
+            log_fn("info", "Mixxx stopped — will restart after backup")
+        else:
+            warn("Mixxx stopped — will restart after backup")
+        time.sleep(1)
+
+    # ── Choose root backup strategy ───────────────────────────────────────────
+    # e2image -r reads ONLY used blocks from disk (fast: ~14 GB reads instead of 59 GB).
+    # It zero-fills unused blocks in the output stream; those zeros compress to nothing.
+    # Fall back to sequential dd of the partition — much faster than tar (sequential
+    # SD reads at 20-40 MB/s vs tar's random seeks at 1-3 MB/s).
+    e2image_bin = ""
+    for candidate in ("/sbin/e2image", "/usr/sbin/e2image", "/bin/e2image"):
+        r_e2 = pi_client.exec(f"test -x {candidate} && echo found || echo ''")
+        if "found" in r_e2["stdout"]:
+            e2image_bin = candidate
+            break
+
+    if e2image_bin:
+        root_cmd   = f"sudo {e2image_bin} -r {root_dev} - 2>/dev/null | {GZIP}"
+        root_file  = "p2-root.img.gz"
+        root_label = "Root ext4 (used blocks via e2image)"
+        root_restore = 'gunzip -c p2-root.img.gz | dd of="$ROOT" bs=4M'
+        ok("Root strategy: e2image -r (reads used blocks only) — fastest")
+    else:
+        root_cmd   = f"sudo dd if={root_dev} bs=4M 2>/dev/null | {GZIP}"
+        root_file  = "p2-root.img.gz"
+        root_label = "Root partition (sequential dd — zeros compress away)"
+        root_restore = 'gunzip -c p2-root.img.gz | dd of="$ROOT" bs=4M'
+        ok("Root strategy: sequential dd + gzip (e2image not found; zeros compress fine)")
+
+    restore_sh = (
+        "#!/bin/bash\n"
+        "# XDJ Pi Image Restore\n"
+        "# Usage: sudo bash restore.sh /dev/sdX\n"
+        "set -e\n"
+        "\n"
+        'DEV="${1:?Usage: sudo bash restore.sh /dev/sdX}"\n'
+        'if ! test -b "$DEV"; then echo "Error: $DEV is not a block device" >&2; exit 1; fi\n'
+        "\n"
+        'if [[ "$DEV" == *mmcblk* ]] || [[ "$DEV" == *nvme* ]]; then\n'
+        '    BOOT="${DEV}p1"; ROOT="${DEV}p2"\n'
+        "else\n"
+        '    BOOT="${DEV}1"; ROOT="${DEV}2"\n'
+        "fi\n"
+        "\n"
+        'echo "==> Restoring partition table"\n'
+        'sfdisk "$DEV" < sfdisk.dump\n'
+        "sleep 2; partprobe \"$DEV\" 2>/dev/null || true; sleep 1\n"
+        "\n"
+        'echo "==> Restoring MBR"\n'
+        'gunzip -c mbr.bin.gz | dd of="$DEV" bs=1M count=1 conv=notrunc\n'
+        "\n"
+        'echo "==> Restoring boot partition"\n'
+        'gunzip -c p1-boot.vfat.gz | dd of="$BOOT" bs=4M\n'
+        "\n"
+        'echo "==> Restoring root partition (this takes several minutes)"\n'
+        f"{root_restore}\n"
+        "\n"
+        'echo "==> Checking + resizing root filesystem"\n'
+        'e2fsck -f "$ROOT" || true\n'
+        'resize2fs "$ROOT"\n'
+        "\n"
+        'echo "==> Done. You can now boot from $DEV"\n'
+    ).encode()
+
+    cancelled = False
+    with tempfile.TemporaryDirectory() as tmpdir:
+        tmp = Path(tmpdir)
+        try:
+            _stream("MBR (1 MiB)",           f"sudo dd if={disk_dev} bs=1M count=1 2>/dev/null | {GZIP}", tmp / "mbr.bin.gz")
+            _stream("Boot partition (FAT32)", f"sudo dd if={boot_dev} bs=4M 2>/dev/null | {GZIP}",         tmp / "p1-boot.vfat.gz")
+            _stream(root_label,               root_cmd,                                                     tmp / root_file)
+        except KeyboardInterrupt:
+            cancelled = True
+
+        if cancelled:
+            if mixxx_was_running:
+                pi_client.exec(f"sudo -u {_PI_USER} DISPLAY=:0 mixxx --settingsPath {_H}/.mixxx &", timeout=5)
+            warn("Cancelled — no output written")
+            return None
+
+        print()
+        with Step("Building manifest"):
+            manifest_txt = _backup_manifest(pi_client)
+            (tmp / "manifest.txt").write_bytes(manifest_txt)
+
+        with Step("Writing archive"):
+            (tmp / "restore.sh").write_bytes(restore_sh)
+            (tmp / "sfdisk.dump").write_bytes(sfdisk_dump)
+            with tarfile.open(out, "w") as tar:
+                for name in ("mbr.bin.gz", "sfdisk.dump", "p1-boot.vfat.gz", root_file, "restore.sh", "manifest.txt"):
+                    ti = tarfile.TarInfo(name=name)
+                    src = tmp / name
+                    ti.size = src.stat().st_size
+                    if name == "restore.sh":
+                        ti.mode = 0o755
+                    with open(src, "rb") as fh:
+                        tar.addfile(ti, fh)
+
+    if mixxx_was_running:
+        pi_client.exec(f"sudo -u {_PI_USER} DISPLAY=:0 mixxx --settingsPath {_H}/.mixxx &", timeout=5)
+        if log_fn:
+            log_fn("info", "Mixxx restarted")
+        else:
+            ok("Mixxx restarted")
+
+    size_mb = out.stat().st_size / 1024**2
+    summary = f"Backup complete — {size_mb:.0f} MB  →  {out}"
+    if log_fn:
+        log_fn("ok", summary)
+        log_fn("info", "Restore (Linux):  tar xf <backup>.tar && sudo bash restore.sh /dev/sdX")
+    else:
+        print()
+        ok(summary)
+        ok("Restore (Linux):  tar xf <backup>.tar && sudo bash restore.sh /dev/sdX")
+    return str(out)
diff --git a/tools/xdj_pi_dev/config.py b/tools/xdj_pi_dev/config.py
new file mode 100644
index 0000000..27943a9
--- /dev/null
+++ b/tools/xdj_pi_dev/config.py
@@ -0,0 +1,127 @@
+from __future__ import annotations
+
+"""
+Config layer — owns all path resolution and the config file.
+
+In dev mode (python3 xdj-pi-dev.py): paths resolve from __file__ inside the repo.
+In standalone mode (PyInstaller frozen binary): paths come from ~/.xdj-pi-dev/config.json.
+"""
+
+import json
+import os
+import sys
+from pathlib import Path
+
+# True only when running inside a PyInstaller bundle
+_FROZEN: bool = getattr(sys, "frozen", False)
+
+CONFIG_PATH = Path.home() / ".xdj-pi-dev" / "config.json"
+
+# Keys stored in the config file
+KEYS = ["skin_dir", "midi_dir", "firmware_dir", "backup_dir", "host", "board", "ssh_user", "ssh_pass"]
+
+# Supported boards — only "pico" has full feature support right now
+BOARDS = ["pico", "pico2", "teensy", "arduino", "unknown"]
+PICO_BOARDS = {"pico", "pico2"}  # boards that support UF2 bootloader + flash
+
+
+def load_config() -> dict:
+    """Read config file; return {} if missing or corrupt."""
+    try:
+        return json.loads(CONFIG_PATH.read_text())
+    except (FileNotFoundError, json.JSONDecodeError):
+        return {}
+
+
+def save_config(data: dict) -> None:
+    """Write config to disk, creating parent dir if needed."""
+    CONFIG_PATH.parent.mkdir(parents=True, exist_ok=True)
+    CONFIG_PATH.write_text(json.dumps(data, indent=2))
+
+
+def update_config(**kwargs) -> None:
+    """Merge kwargs into existing config and save."""
+    cfg = load_config()
+    cfg.update(kwargs)
+    save_config(cfg)
+
+
+def config_complete() -> bool:
+    """True when all required path keys have values."""
+    cfg = load_config()
+    return all(cfg.get(k) for k in ["skin_dir", "midi_dir"])
+
+
+def get_board() -> str:
+    """Return board name from config; default 'pico' in dev mode."""
+    if _FROZEN:
+        return load_config().get("board", "unknown")
+    return load_config().get("board", "pico")
+
+
+def is_pico_board() -> bool:
+    return get_board() in PICO_BOARDS
+
+
+# ─── Path getters ─────────────────────────────────────────────────────────────
+
+def _repo_root() -> Path:
+    """Repo root — only valid in dev mode."""
+    return Path(__file__).resolve().parent.parent.parent
+
+
+def get_skin_dir() -> Path:
+    if _FROZEN:
+        p = load_config().get("skin_dir")
+        if not p:
+            raise RuntimeError("Skin folder not configured — open Settings.")
+        return Path(p)
+    return _repo_root() / "mixxx" / "SKIN" / "XDJ100SX"
+
+
+def get_midi_dir() -> Path:
+    if _FROZEN:
+        p = load_config().get("midi_dir")
+        if not p:
+            raise RuntimeError("MIDI folder not configured — open Settings.")
+        return Path(p)
+    return _repo_root() / "mixxx" / "MIDI"
+
+
+def get_firmware_dir() -> Path:
+    if _FROZEN:
+        p = load_config().get("firmware_dir")
+        if not p:
+            raise RuntimeError("Firmware folder not configured — open Settings.")
+        return Path(p)
+    return _repo_root() / "arduino" / "pico"
+
+
+def get_backup_dir() -> Path:
+    if _FROZEN:
+        p = load_config().get("backup_dir")
+        if p:
+            return Path(p)
+    # Default: cwd for dev, ~/Downloads/XDJ-Backups for standalone
+    if _FROZEN:
+        d = Path.home() / "Downloads" / "XDJ-Backups"
+        d.mkdir(parents=True, exist_ok=True)
+        return d
+    return _repo_root()
+
+
+def get_saved_host() -> str | None:
+    """Return the remembered Pi host, or None if not set."""
+    return load_config().get("host") or None
+
+
+def get_ssh_user() -> str:
+    """SSH username: config file → XDJ_USER env → built-in default."""
+    v = load_config().get("ssh_user")
+    return v if v else os.environ.get("XDJ_USER", "xdj100sx")
+
+
+def get_ssh_pass() -> str:
+    """SSH password: config file → XDJ_PASS env → built-in default."""
+    v = load_config().get("ssh_pass")
+    return v if v else os.environ.get("XDJ_PASS", "xdj100sx")
diff --git a/tools/xdj_pi_dev/image_utils.py b/tools/xdj_pi_dev/image_utils.py
new file mode 100644
index 0000000..309ee97
--- /dev/null
+++ b/tools/xdj_pi_dev/image_utils.py
@@ -0,0 +1,127 @@
+from __future__ import annotations
+
+"""
+Image utilities: white-background removal and PIL-image → Rich-Text rendering.
+
+Half-block trick: the ▄ character covers the BOTTOM half of a terminal cell.
+  • Both halves opaque  → bgcolor=top, color=bottom, char=▄
+  • Top transparent     → color=bottom, no bgcolor (panel bg shows through), char=▄
+  • Bottom transparent  → color=top, no bgcolor, char=▀  (upper-half block)
+  • Both transparent    → space (panel background shows through)
+
+This avoids any fixed background-colour guessing, so the image blends naturally
+against whatever Textual's panel colour happens to be.
+"""
+
+from pathlib import Path
+from typing import TYPE_CHECKING
+
+if TYPE_CHECKING:
+    from PIL import Image as _PILImage
+
+_IMAGES_DIR = Path(__file__).parent / "images"
+
+# Pixels with alpha below this are treated as fully transparent
+_ALPHA_THRESH = 80
+
+
+def _remove_white_bg(img: "_PILImage.Image", threshold: int = 230) -> "_PILImage.Image":
+    """
+    BFS flood-fill from all four corners: connected white pixels become transparent.
+    Corner-flood avoids touching white silkscreen text on the board itself.
+    """
+    img = img.convert("RGBA")
+    w, h = img.size
+    pixels = img.load()
+
+    def _is_white(px) -> bool:
+        return px[0] >= threshold and px[1] >= threshold and px[2] >= threshold
+
+    visited: set[tuple[int, int]] = set()
+    queue: list[tuple[int, int]] = []
+    for sx, sy in [(0, 0), (w - 1, 0), (0, h - 1), (w - 1, h - 1)]:
+        if _is_white(pixels[sx, sy]) and (sx, sy) not in visited:
+            queue.append((sx, sy))
+            visited.add((sx, sy))
+
+    while queue:
+        x, y = queue.pop()
+        r, g, b, _ = pixels[x, y]
+        pixels[x, y] = (r, g, b, 0)
+        for nx, ny in ((x - 1, y), (x + 1, y), (x, y - 1), (x, y + 1)):
+            if 0 <= nx < w and 0 <= ny < h and (nx, ny) not in visited:
+                if _is_white(pixels[nx, ny]):
+                    visited.add((nx, ny))
+                    queue.append((nx, ny))
+
+    return img
+
+
+def img_to_rich(img: "_PILImage.Image", target_width: int = 32) -> object:
+    """
+    Convert a PIL RGBA image to a Rich Text object using half-block characters.
+    Transparent areas render as plain spaces so the panel background shows through.
+    Returns a rich.text.Text ready to pass to Static() or RichLog.write().
+    """
+    from PIL import Image
+    from rich.text import Text
+    from rich.style import Style
+    from rich.color import Color
+
+    aspect = img.height / img.width
+    target_height = max(2, int(target_width * aspect * 0.5) * 2)  # must be even
+    img = img.resize((target_width, target_height), Image.LANCZOS).convert("RGBA")
+    pixels = img.load()
+
+    result = Text(no_wrap=True)
+    for row in range(0, target_height, 2):
+        if row > 0:
+            result.append("\n")
+        for col in range(target_width):
+            tr, tg, tb, ta = pixels[col, row]
+            br, bg, bb, ba  = pixels[col, min(row + 1, target_height - 1)]
+            top_opaque = ta > _ALPHA_THRESH
+            bot_opaque = ba > _ALPHA_THRESH
+
+            if not top_opaque and not bot_opaque:
+                # Both transparent — let the panel background show through
+                result.append(" ")
+            elif top_opaque and bot_opaque:
+                # Both opaque — full half-block encoding
+                result.append("▄", style=Style(
+                    bgcolor=Color.from_rgb(tr, tg, tb),
+                    color=Color.from_rgb(br, bg, bb),
+                ))
+            elif not top_opaque and bot_opaque:
+                # Bottom opaque, top transparent — ▄ with no background
+                result.append("▄", style=Style(color=Color.from_rgb(br, bg, bb)))
+            else:
+                # Top opaque, bottom transparent — upper-half block, no background
+                result.append("▀", style=Style(color=Color.from_rgb(tr, tg, tb)))
+    return result
+
+
+def load_board_rich(board_key: str, target_width: int = 32) -> object | None:
+    """
+    Load, background-remove, and render a board image as Rich Text.
+    Returns None if Pillow is not installed or the image is missing.
+    board_key: 'pico' | 'pico2' | 'teensy'
+    """
+    _FILE_MAP = {
+        "pico":   "raspberry pi pico.png",
+        "pico2":  "raspberry pi pico 2.png",
+        "teensy": "teensy 4-0.png",
+    }
+    fname = _FILE_MAP.get(board_key)
+    if not fname:
+        return None
+    path = _IMAGES_DIR / fname
+    if not path.exists():
+        return None
+    try:
+        from PIL import Image
+        img = Image.open(path)
+        img = _remove_white_bg(img)
+        return img_to_rich(img, target_width)
+    except Exception:
+        return None
diff --git a/tools/xdj_pi_dev/messages.py b/tools/xdj_pi_dev/messages.py
new file mode 100644
index 0000000..05a5415
--- /dev/null
+++ b/tools/xdj_pi_dev/messages.py
@@ -0,0 +1,99 @@
+from __future__ import annotations
+
+"""
+All user-visible strings in one place.
+Use MSG["key"].format(...) for parametric messages.
+"""
+
+MSG: dict[str, str] = {
+    # Connection
+    "connecting":           "Connecting to {host}…",
+    "connected":            "Connected to {host}",
+    "not_connected":        "Not connected yet — connect to the Pi first.",
+    "already_connecting":   "Already connecting — please wait.",
+    "cant_reach_pi":        "Can't find the Raspberry Pi. Check that it's powered on and connected.",
+    "cant_reach_pi_detail": (
+        "Can't find the Raspberry Pi.\n"
+        "Tried: {tried}\n"
+        "If using a direct cable, set up the network alias first:\n"
+        "{instructions}"
+    ),
+
+    # General operation state
+    "busy":                 "Still working on the last task — please wait.",
+    "op_cancelled":         "Operation cancelled.",
+
+    # Push / pull
+    "pushing_skin":         "Sending skin files to Pi…",
+    "pushing_skin_backup":  "Sending skin files to Pi (saving remote copy first)…",
+    "pushed_skin":          "Sent {n} file(s) to Pi.",
+    "pulling_skin":         "Getting skin files from Pi…",
+    "pulling_skin_backup":  "Getting skin files from Pi (saving local copy first)…",
+    "pulled_skin":          "Got {n} file(s) from Pi.",
+    "pushing_midi":         "Sending MIDI mapping to Pi…",
+    "pushing_midi_backup":  "Sending MIDI mapping to Pi (saving remote copy first)…",
+    "pushed_midi":          "Sent {n} MIDI file(s) to Pi.",
+    "pulling_midi":         "Getting MIDI mapping from Pi…",
+    "pulling_midi_backup":  "Getting MIDI mapping from Pi (saving local copy first)…",
+    "pulled_midi":          "Got {n} MIDI file(s) from Pi.",
+    "midi_reload":          "Done. To apply: open Mixxx → Preferences → Controllers and reload the mapping.",
+
+    # Screenshot
+    "screenshotting":       "Capturing Pi display…",
+    "screenshot_saved":     "Screenshot saved.",
+
+    # Mixxx
+    "restarting_mixxx":     "Restarting Mixxx…",
+    "mixxx_restarted":      "Mixxx restarted.",
+
+    # Watch mode
+    "watch_started":        (
+        "Watch mode ON\n"
+        "Watching local skin folder for changes.\n"
+        "Workflow: edit any skin XML on your Mac → save → file is pushed to the Pi\n"
+        "automatically → Mixxx reloads the skin (Ctrl+F5) → screenshot opens here.\n"
+        "No manual Push Skin needed while Watch is running."
+    ),
+    "watch_stopped":        "Watch mode OFF.",
+
+    # Pico bootloader
+    "pico_boot_starting":   "Sending update signal to Pico…",
+    "pico_boot_ok":         "Pico is in update mode. Click Flash UF2.",
+    "pico_boot_likely":     (
+        "Update signal sent — waiting for Pico to appear as a USB drive…\n"
+        "If Flash UF2 fails, wait a few more seconds then try again."
+    ),
+    "pico_boot_fail":       (
+        "Couldn't confirm Pico is in update mode.\n"
+        "Try clicking Bootloader first, then Flash UF2."
+    ),
+
+    # Pico flash
+    "flashing":             "Installing firmware on Pico…",
+    "flash_ok":             "Firmware installed successfully.",
+    "flash_fail_nofile":    "No firmware file found. Compile the firmware first.",
+    "flash_fail_nodev":     (
+        "Couldn't find Pico in update mode after 30 seconds.\n"
+        "Click Bootloader first, then try Flash UF2 again."
+    ),
+    "flash_fail_copy":      "Firmware file could not be written to Pico.",
+    "pico_alive":           "Pico is running on {port}.",
+    "pico_midi_ok":         "MIDI is visible — reload the mapping in Mixxx: Preferences → Controllers",
+    "pico_midi_wait":       "Pico is running but MIDI isn't visible yet — restart Mixxx.",
+
+    # Setup / check
+    "preflight_start":      "Pre-flight check…",
+    "ssh_keys_starting":    "Setting up SSH key login…",
+    "dhcp_starting":        "Configuring Pi DHCP server…",
+    "discovering":          "Scanning network for Pi units…",
+    "no_units_found":       "No Pi units found — check cable / network.",
+    "backup_starting":      "Pi backup — reading used blocks only… (this takes a few minutes)",
+    "backup_wait":          "Do not disconnect while the backup is running.",
+    "backup_saved":         "Backup saved → {path}",
+    "verifying_backup":     "Verifying backup {name}…",
+    "verify_ok":            "Backup file looks good.",
+
+    # Signal analyzer
+    "signal_an_started":    "Signal Analyzer → {url}",
+    "signal_an_stopped":    "Signal Analyzer stopped.",
+}
diff --git a/tools/xdj_pi_dev/midi.py b/tools/xdj_pi_dev/midi.py
new file mode 100644
index 0000000..8172bf8
--- /dev/null
+++ b/tools/xdj_pi_dev/midi.py
@@ -0,0 +1,126 @@
+from __future__ import annotations
+
+"""
+MIDI monitor — stream live MIDI events from the Pico via aseqdump / amidi.
+
+Extracted from xdj-pi-dev.py (lines 742-843).
+"""
+
+import re
+import threading
+import time
+
+from xdj_pi_dev._terminal import _tui_log_fn  # noqa: F401 — re-exported for callers
+
+
+# ─── MIDI line parser ─────────────────────────────────────────────────────────
+
+def _fmt_midi_line(text: str) -> tuple[str, str] | None:
+    """Parse one aseqdump or amidi -d line → (log_type, formatted_string) or None."""
+    t = text.strip()
+    if not t or t.startswith("Source") or t.startswith("Waiting") or t.startswith("ALSA"):
+        return None
+
+    # aseqdump: " 20:0   Control change          1, controller 7, value 64"
+    m = re.search(r'Control change\s+(\d+),\s*controller\s+(\d+),\s*value\s+(\d+)', t)
+    if m:
+        ch, ctrl, val = int(m.group(1)), int(m.group(2)), int(m.group(3))
+        bar = "▓" * (val * 16 // 127) + "░" * (16 - val * 16 // 127)
+        return "info", f"CC  ch{ch:2d} ctrl={ctrl:3d}  val={val:3d}  [{bar}]"
+
+    m = re.search(r'Note on\s+(\d+),\s*note\s+(\d+),\s*velocity\s+(\d+)', t)
+    if m:
+        ch, note, vel = int(m.group(1)), int(m.group(2)), int(m.group(3))
+        return "ok", f"NON ch{ch:2d} note={note:3d}  vel={vel:3d}"
+
+    m = re.search(r'Note off\s+(\d+),\s*note\s+(\d+)', t)
+    if m:
+        ch, note = int(m.group(1)), int(m.group(2))
+        return "warn", f"NOF ch{ch:2d} note={note:3d}"
+
+    m = re.search(r'Pitch bend\s+(\d+),\s*value\s+(-?\d+)', t)
+    if m:
+        ch, val = int(m.group(1)), int(m.group(2))
+        return "info", f"PB  ch{ch:2d} val={val:6d}"
+
+    # amidi -d raw hex: "B0 07 40"
+    parts = t.split()
+    if parts and re.match(r'^[0-9A-Fa-f]{2}$', parts[0]):
+        try:
+            status = int(parts[0], 16)
+            mtype = (status & 0xF0) >> 4
+            ch = (status & 0x0F) + 1
+            b1 = int(parts[1], 16) if len(parts) > 1 else 0
+            b2 = int(parts[2], 16) if len(parts) > 2 else 0
+            if mtype == 0xB:
+                bar = "▓" * (b2 * 16 // 127) + "░" * (16 - b2 * 16 // 127)
+                return "info", f"CC  ch{ch:2d} ctrl={b1:3d}  val={b2:3d}  [{bar}]"
+            if mtype == 0x9 and b2 > 0:
+                return "ok",   f"NON ch{ch:2d} note={b1:3d}  vel={b2:3d}"
+            if mtype == 0x8 or (mtype == 0x9 and b2 == 0):
+                return "warn", f"NOF ch{ch:2d} note={b1:3d}"
+            if mtype == 0xE:
+                val = (b2 << 7 | b1) - 8192
+                return "info", f"PB  ch{ch:2d} val={val:6d}"
+        except (ValueError, IndexError):
+            pass
+
+    return "info", t
+
+
+# ─── MIDI monitor ─────────────────────────────────────────────────────────────
+
+def midi_monitor(pi_client, stop_event: threading.Event, emit=None) -> None:
+    """Stream live MIDI from the Pico via aseqdump (falls back to amidi -d).
+
+    Parameters
+    ----------
+    pi_client:
+        A connected PiClient instance.
+    stop_event:
+        Threading event; monitoring stops when set.
+    emit:
+        Optional callable(level, msg) for TUI output.
+    """
+    # Find the Pico's ALSA sequencer port
+    ports_out = pi_client.exec("aconnect -l 2>/dev/null")
+    seq_port = None
+    for line in ports_out["stdout"].splitlines():
+        if "XDJ" in line or "Pico" in line:
+            m = re.search(r'client (\d+):', line)
+            if m:
+                seq_port = f"{m.group(1)}:0"
+                break
+
+    # Build the monitoring command
+    if seq_port:
+        cmd = f"aseqdump -p {seq_port} 2>/dev/null || amidi -p hw:1,0,0 -d 2>&1"
+        label = f"aseqdump port {seq_port}"
+    else:
+        cmd = "amidi -p hw:1,0,0 -d 2>&1"
+        label = "amidi hw:1,0,0"
+
+    if emit:
+        emit("head", f"MIDI monitor — {label}  (press button to stop)")
+
+    transport = pi_client._ssh.get_transport()
+    assert transport
+    channel = transport.open_session()
+    channel.set_combine_stderr(True)
+    channel.exec_command(cmd)
+
+    buf = b""
+    while not stop_event.is_set():
+        if channel.recv_ready():
+            buf += channel.recv(4096)
+            while b"\n" in buf:
+                raw, buf = buf.split(b"\n", 1)
+                parsed = _fmt_midi_line(raw.decode(errors="replace"))
+                if parsed and emit:
+                    emit(*parsed)
+        elif channel.exit_status_ready() and not channel.recv_ready():
+            break
+        else:
+            time.sleep(0.02)
+
+    channel.close()
diff --git a/tools/xdj_pi_dev/pico_tools.py b/tools/xdj_pi_dev/pico_tools.py
new file mode 100644
index 0000000..11869fe
--- /dev/null
+++ b/tools/xdj_pi_dev/pico_tools.py
@@ -0,0 +1,453 @@
+from __future__ import annotations
+
+"""
+Pico firmware tools: bootloader, flash, compile, and CLI setup.
+
+Extracted from xdj-pi-dev.py (lines 577-741 and 853-1101).
+"""
+
+import os
+import shutil
+import subprocess
+import sys
+import tempfile
+import time
+from pathlib import Path
+
+from xdj_pi_dev._terminal import (
+    _C, Step, section, ok, warn, fail, _log_line,
+)
+from xdj_pi_dev.messages import MSG
+
+# ─── Module-level constants ───────────────────────────────────────────────────
+
+# Resolve relative to this file: xdj_pi_dev/ → tools/ → repo root
+_REPO_ROOT = Path(__file__).resolve().parent.parent.parent
+_PI_USER   = os.environ.get("XDJ_USER", "xdj100sx")
+
+REPO_FIRMWARE   = _REPO_ROOT / "arduino" / "pico" / "pico-XDJ100SX.ino"
+PI_FIRMWARE_DIR = f"/home/{_PI_USER}/pico-firmware"
+PI_FIRMWARE_INO = f"{PI_FIRMWARE_DIR}/pico-XDJ100SX.ino"
+PI_BUILD_DIR    = f"{PI_FIRMWARE_DIR}/build"
+ARDUINO_CLI_URL = (
+    "https://downloads.arduino.cc/arduino-cli/arduino-cli_latest_Linux_ARMv7.tar.gz"
+)
+ARDUINO_BOARD_URL = (
+    "https://github.com/earlephilhower/arduino-pico/releases/download/global/"
+    "package_rp2040_index.json"
+)
+
+# Board profiles: short name → full FQBN
+# rp2040 boards need usbstack=tinyusb for Adafruit TinyUSB to compile
+BOARD_PROFILES: dict[str, str] = {
+    "pico":      "rp2040:rp2040:rpipico:usbstack=tinyusb",
+    "pico2":     "rp2040:rp2040:rpipico2:usbstack=tinyusb",
+    "picow":     "rp2040:rp2040:rpipicow:usbstack=tinyusb",
+    "micro":     "arduino:avr:micro",
+    "leonardo":  "arduino:avr:leonardo",
+    "uno":       "arduino:avr:uno",
+    "nano":      "arduino:avr:nano",
+}
+DEFAULT_BOARD = "pico"
+
+
+# ─── Pico bootloader ──────────────────────────────────────────────────────────
+
+def pico_bootloader(pi_client) -> str:
+    """
+    Reset the Pico into UF2 bootloader mode via MIDI Note 127 ch16 vel127.
+
+    Mixxx holds the ALSA MIDI port while running, so we must stop it first.
+    amidi (already on Pi) is used — no Python dependencies needed.
+    Mixxx auto-restarts via the xinitrc while-loop after ~2-3 s.
+    """
+    # Kill Mixxx so it releases the ALSA port; SIGTERM then SIGKILL to be sure
+    ok("Stopping Mixxx…")
+    pi_client.exec(
+        "pkill -x mixxx 2>/dev/null; sleep 2; pkill -9 -x mixxx 2>/dev/null; true",
+        timeout=10,
+    )
+    time.sleep(1)   # let ALSA finish releasing the port
+
+    # Find Pico MIDI port via amidi -l; default to hw:1,0,0 (card 1 = USB)
+    ports_r = pi_client.exec("amidi -l 2>&1")
+    port = "hw:1,0,0"
+    for line in ports_r["stdout"].splitlines():
+        if "XDJ" in line or "Pico" in line or "USB" in line.upper():
+            for tok in line.split():
+                if tok.startswith("hw:"):
+                    port = tok
+                    break
+
+    ok(f"Sending update signal via {port}…")
+    # Note On: status 0x9F = ch16, note 0x7F = 127, vel 0x7F = 127.
+    # Shell timeout prevents hang if the Pico reboots and amidi stalls on ALSA cleanup.
+    # rc=124 means shell killed amidi = port vanished during send = likely success.
+    r = pi_client.exec(f"timeout 6 amidi -p {port} -S '9F 7F 7F' 2>&1", timeout=10)
+    amidi_out = r["stdout"].strip()
+    amidi_rc  = r["rc"]
+
+    if amidi_rc not in (0, 124) and amidi_out:
+        # amidi returned a real error — port busy, not found, etc.
+        return f"amidi error (rc={amidi_rc}): {amidi_out}"
+
+    time.sleep(3)  # give Pico time to enumerate as mass storage
+
+    # Broad detection: check by-label symlink (most reliable), then lsblk fallbacks
+    check = pi_client.exec(
+        "ls /dev/disk/by-label/RPI-RP2 2>/dev/null && echo BY_LABEL;"
+        "lsblk -no NAME,LABEL  2>/dev/null | grep -i RPI-RP2  && echo BY_LABEL_LSBLK;"
+        "lsblk -no NAME,VENDOR 2>/dev/null | grep -i raspberr && echo BY_VENDOR;"
+        "lsblk -no NAME,MODEL  2>/dev/null | grep -iE 'RP2|RPI' && echo BY_MODEL;"
+        "mountpoint -q /media/RPI-RP2 2>/dev/null && echo MOUNTED || true"
+    )
+    found = any(k in check["stdout"] for k in ("BY_LABEL", "BY_VENDOR", "BY_MODEL", "MOUNTED"))
+    if found:
+        return MSG["pico_boot_ok"]
+
+    # Port vanished (amidi hung and was killed, or returned "No such") → likely in bootloader
+    if amidi_rc == 124 or not amidi_out or "No such" in amidi_out or "cannot open" in amidi_out:
+        ok("Update signal sent — Pico is rebooting into update mode…")
+        time.sleep(4)
+        check2 = pi_client.exec(
+            "ls /dev/disk/by-label/RPI-RP2 2>/dev/null && echo BY_LABEL;"
+            "lsblk -no NAME,LABEL  2>/dev/null | grep -i RPI-RP2 && echo BY_LABEL_LSBLK || true"
+        )
+        if any(k in check2["stdout"] for k in ("BY_LABEL", "BY_LABEL_LSBLK")):
+            return MSG["pico_boot_ok"]
+        return MSG["pico_boot_likely"]
+
+    return MSG["pico_boot_fail"]
+
+
+# ─── Pico flash ───────────────────────────────────────────────────────────────
+
+def pico_flash(pi_client, local_uf2_path: str) -> str:
+    local = Path(local_uf2_path)
+    if not local.exists():
+        return f"File not found: {local}"
+
+    ok(f"Uploading {local.name} to Pi…")
+    remote_uf2 = f"/tmp/{local.name}"
+    pi_client.write_bytes(remote_uf2, local.read_bytes())
+
+    # Try picotool first (cleanest method — works if installed on Pi)
+    r = pi_client.exec(f"picotool load {remote_uf2} --force 2>&1", timeout=8)
+    if r["rc"] == 0:
+        return f"Flashed via picotool: {local.name}\n{r['stdout'].strip()}"
+
+    ok("Locating RPI-RP2 block device and mounting…")
+
+    # Shell script that:
+    # 1. Finds the Pico block device via lsblk VENDOR (reads sysfs — no blkid probe, no hang)
+    # 2. Mounts it with uid=1000 so the pi user can write (or uses sudo if already root-mounted)
+    # 3. Verifies the mount with mountpoint before writing (not just directory existence)
+    # 4. Runs cp and checks its exit code separately — a leftover empty dir won't fool us
+    # 5. sync before umount to force page-cache flush to the Pico
+    flash_script = (
+        "MPOINT=/media/RPI-RP2\n"
+        f"UF2={remote_uf2}\n"
+        "mkdir -p \"$MPOINT\"\n"
+        "for i in $(seq 1 30); do\n"
+        # 1. by-label symlink (most reliable, set by udev on Raspberry Pi OS)
+        "    DEV=$(readlink -f /dev/disk/by-label/RPI-RP2 2>/dev/null)\n"
+        # 2. lsblk by LABEL
+        "    [ -z \"$DEV\" ] && DEV=$(lsblk -no NAME,LABEL 2>/dev/null"
+        " | awk '$2==\"RPI-RP2\"{print \"/dev/\"$1}'"
+        " | grep -v mmcblk | head -1)\n"
+        # 3. lsblk by MODEL (RP2 Boot, RP2, RPI-RP2)
+        "    if [ -z \"$DEV\" ]; then\n"
+        "        DISK=$(lsblk -no NAME,MODEL 2>/dev/null"
+        " | awk '$2~/^RP2|^RPI/{print $1}'"
+        " | grep -v mmcblk | head -1)\n"
+        "        [ -n \"$DISK\" ] && { if [ -b \"/dev/${DISK}1\" ]; then DEV=\"/dev/${DISK}1\"; else DEV=\"/dev/$DISK\"; fi; }\n"
+        "    fi\n"
+        # 4. lsblk by VENDOR (RaspberryPi, Raspberry)
+        "    [ -z \"$DEV\" ] && DEV=$(lsblk -no NAME,VENDOR 2>/dev/null"
+        " | awk 'tolower($2)~/raspberr/{print \"/dev/\"$1}'"
+        " | grep -v mmcblk | head -1)\n"
+        "    if [ -n \"$DEV\" ]; then\n"
+        "        if ! mountpoint -q \"$MPOINT\" 2>/dev/null; then\n"
+        "            sudo mount -t vfat -o uid=1000,gid=1000,sync \"$DEV\" \"$MPOINT\" 2>/dev/null"
+        " || sudo mount -t vfat -o sync \"$DEV\" \"$MPOINT\" 2>/dev/null || true\n"
+        "        fi\n"
+        "        if mountpoint -q \"$MPOINT\" 2>/dev/null; then\n"
+        "            echo \"MOUNTED:$DEV\"\n"
+        "            cp \"$UF2\" \"$MPOINT/fw.uf2\"\n"
+        "            CP_RC=$?\n"
+        "            sync\n"
+        "            sudo umount \"$MPOINT\" 2>/dev/null || true\n"
+        "            if [ \"$CP_RC\" -eq 0 ]; then\n"
+        "                echo FLASHED\n"
+        "                exit 0\n"
+        "            else\n"
+        "                echo \"CP_FAILED:$CP_RC\"\n"
+        "                exit 1\n"
+        "            fi\n"
+        "        fi\n"
+        "    fi\n"
+        "    sleep 1\n"
+        "done\n"
+        "echo NOTMOUNTED\n"
+        "exit 1\n"
+    )
+    r2 = pi_client.exec(flash_script, timeout=60)
+    stdout = r2["stdout"]
+
+    if "CP_FAILED" in stdout:
+        return MSG["flash_fail_copy"]
+    if "NOTMOUNTED" in stdout:
+        return MSG["flash_fail_nodev"]
+    if "FLASHED" not in stdout:
+        return f"Flash failed — unexpected output:\n{stdout}"
+
+    ok("UF2 sent — waiting for Pico to reboot into firmware…")
+    for i in range(45):
+        time.sleep(1)
+        # Match any ttyACM* in case enumeration picks a different index
+        chk = pi_client.exec(
+            "ls /dev/ttyACM* 2>/dev/null | head -1 || echo WAITING",
+            timeout=5,
+        )
+        port = chk["stdout"].strip()
+        if port and port != "WAITING":
+            ok(MSG["pico_alive"].format(port=port))
+            midi = pi_client.exec("aconnect -l 2>/dev/null | grep -i xdj || echo NOT_VISIBLE", timeout=5)
+            if "NOT_VISIBLE" not in midi["stdout"]:
+                ok(MSG["pico_midi_ok"])
+            else:
+                warn(MSG["pico_midi_wait"])
+            return MSG["flash_ok"]
+
+    return (
+        "UF2 was sent successfully but /dev/ttyACM* did not appear within 45 s.\n"
+        "The firmware is on the Pico — it is not lost.\n"
+        "Wait a few more seconds then run:  python3 xdj-pi-dev.py --status\n"
+        "If still missing, unplug and replug the Pico USB cable on the Pi."
+    )
+
+
+# ─── Pico CLI setup ───────────────────────────────────────────────────────────
+
+def setup_pico_cli(pi_client) -> None:
+    """
+    One-time setup: install arduino-cli on the Pi, add the arduino-pico core,
+    and install the required libraries.  Downloads ~500 MB of toolchain.
+    Mixxx is stopped during the download/install to free RAM, then restarted.
+    """
+    section("Pico Toolchain Setup  (one-time, ~500 MB download)")
+    print(f"  {_C.DIM}Mixxx will be stopped during this operation.{_C.RESET}\n")
+
+    with Step("Stopping Mixxx"):
+        pi_client.exec("killall mixxx 2>/dev/null; true", timeout=5)
+        time.sleep(2)
+
+    with Step("Creating firmware directory"):
+        pi_client.exec(f"mkdir -p {PI_FIRMWARE_DIR} {PI_BUILD_DIR}")
+
+    # Download arduino-cli if not present
+    cli_present = pi_client.exec("which arduino-cli")
+    if cli_present["rc"] != 0:
+        with Step("Downloading arduino-cli"):
+            rc = pi_client.exec_stream(
+                f"cd /tmp && curl -fsSL {ARDUINO_CLI_URL} | tar xz arduino-cli"
+                f" && sudo mv /tmp/arduino-cli /usr/local/bin/ && echo ok",
+                timeout=120,
+            )
+            if rc != 0:
+                fail("arduino-cli download failed — check internet connection on Pi")
+                with Step("Restarting Mixxx"):
+                    pi_client.exec("killall mixxx 2>/dev/null; true")
+                return
+    else:
+        ok(f"arduino-cli already installed ({cli_present['stdout'].strip()})")
+
+    with Step("Initialising arduino-cli config"):
+        pi_client.exec("arduino-cli config init --overwrite 2>/dev/null; true")
+        pi_client.exec(
+            f"arduino-cli config add board_manager.additional_urls {ARDUINO_BOARD_URL}"
+        )
+
+    with Step("Updating board index"):
+        pi_client.exec_stream("arduino-cli core update-index 2>&1", timeout=60)
+
+    print(f"\n  {_C.DIM}Installing RP2040 core + ARM toolchain (~500 MB)…{_C.RESET}")
+    print(f"  {_C.GRAY}│{_C.RESET}")
+    rc = pi_client.exec_stream("arduino-cli core install rp2040:rp2040 2>&1", timeout=900)
+    if rc != 0:
+        fail("Core install failed")
+    else:
+        ok("RP2040 core installed")
+
+    print()
+    with Step("Installing Adafruit TinyUSB"):
+        pi_client.exec_stream(
+            'arduino-cli lib install "Adafruit TinyUSB Library" 2>&1', timeout=120
+        )
+    with Step("Installing MIDI Library"):
+        pi_client.exec_stream('arduino-cli lib install "MIDI Library" 2>&1', timeout=60)
+    with Step("Installing Bounce2"):
+        pi_client.exec_stream('arduino-cli lib install "Bounce2" 2>&1', timeout=60)
+
+    with Step("Restarting Mixxx"):
+        time.sleep(4)
+        pi_client.exec("killall mixxx 2>/dev/null; true")
+
+    print()
+    ok("Toolchain ready — run --pico-compile to build firmware")
+
+
+# ─── Private compile helpers ──────────────────────────────────────────────────
+
+def _resolve_fqbn(board: str) -> str:
+    """Resolve a board name or raw FQBN to a full FQBN string."""
+    return BOARD_PROFILES.get(board, board)
+
+
+def _compile_local(fqbn: str, ino: Path) -> Path:
+    """
+    Compile firmware using arduino-cli on this machine.
+    Returns path to the produced .uf2 (or .hex for AVR).
+    Raises RuntimeError on failure.
+    """
+    build_dir = Path(tempfile.mkdtemp(prefix="xdj-build-"))
+    # arduino-cli requires sketch dir name == .ino stem
+    sketch_dir = build_dir / ino.stem
+    sketch_dir.mkdir()
+    shutil.copy(ino, sketch_dir / ino.name)
+
+    r = subprocess.run(
+        [
+            "arduino-cli", "compile",
+            "--fqbn", fqbn,
+            "--output-dir", str(build_dir),
+            "--warnings", "none",
+            str(sketch_dir),
+        ],
+        capture_output=True,
+        text=True,
+    )
+    if r.returncode != 0:
+        raise RuntimeError((r.stderr or r.stdout).strip())
+
+    artifacts = list(build_dir.glob("*.uf2")) or list(build_dir.glob("*.hex"))
+    if not artifacts:
+        raise RuntimeError("Compile succeeded but no .uf2/.hex found in output dir")
+    return artifacts[0]
+
+
+def _compile_on_pi(pi_client, fqbn: str, ino: Path) -> str:
+    """
+    Push firmware to Pi and compile there.
+    Returns the remote path of the produced .uf2.
+    Raises RuntimeError on failure.
+    """
+    pi_sketch_dir = f"{PI_FIRMWARE_DIR}/{ino.stem}"
+    pi_ino        = f"{pi_sketch_dir}/{ino.name}"
+
+    pi_client.exec(f"mkdir -p {pi_sketch_dir} {PI_BUILD_DIR}")
+    pi_client.write_bytes(pi_ino, ino.read_bytes())
+
+    w   = shutil.get_terminal_size((72, 24)).columns
+    bar = _C.GRAY + "─" * min(w - 4, 68) + _C.RESET
+    print(f"\n  {bar}")
+    t0  = time.time()
+    rc  = pi_client.exec_stream(
+        f"arduino-cli compile --fqbn {fqbn}"
+        f" --output-dir {PI_BUILD_DIR} --warnings none {pi_ino} 2>&1",
+        timeout=300,
+    )
+    print(f"  {bar}\n")
+    if rc != 0:
+        raise RuntimeError(f"Compile failed on Pi after {time.time()-t0:.0f}s")
+
+    check = pi_client.exec(f"ls {PI_BUILD_DIR}/*.uf2 {PI_BUILD_DIR}/*.hex 2>/dev/null | head -1")
+    path  = check["stdout"].strip()
+    if not path:
+        raise RuntimeError("Compile finished but no .uf2/.hex found on Pi")
+    return path
+
+
+# ─── Pico compile (top-level) ─────────────────────────────────────────────────
+
+def pico_compile(pi_client, flash: bool = False, board: str = DEFAULT_BOARD) -> None:
+    """
+    Compile firmware then optionally flash.
+    Strategy: local arduino-cli first (faster, no Pi needed); falls back to Pi.
+    """
+    section("Pico Firmware Compile")
+
+    if not REPO_FIRMWARE.exists():
+        fail(f"Firmware not found: {REPO_FIRMWARE}")
+        return
+
+    fqbn = _resolve_fqbn(board)
+    ok(f"Board: {board}  →  {fqbn}")
+
+    local_cli = shutil.which("arduino-cli")
+    pi_cli    = pi_client.exec("which arduino-cli 2>/dev/null")["rc"] == 0
+
+    if not local_cli and not pi_cli:
+        fail("arduino-cli not found — install it first:")
+        print(f"  {_C.CYAN}Mac/Linux:{_C.RESET}  brew install arduino-cli")
+        print(f"  {_C.CYAN}Pi:{_C.RESET}          {sys.argv[0]} --setup-pico-cli  (Pi needs internet)")
+        return
+
+    uf2_local:  Path | None = None   # set if compiled on this machine
+    uf2_remote: str  | None = None   # set if compiled on Pi
+
+    if local_cli:
+        ok(f"Compiling locally  ({local_cli})")
+        t0 = time.time()
+        try:
+            uf2_local = _compile_local(fqbn, REPO_FIRMWARE)
+        except RuntimeError as e:
+            fail(f"Local compile failed:\n{e}")
+            return
+        kb = uf2_local.stat().st_size // 1024
+        ok(f"Done in {time.time()-t0:.0f}s — {uf2_local.name}  ({kb} KB)")
+    else:
+        ok("Compiling on Pi  (arduino-cli found there, local not available)")
+        with Step("Stopping Mixxx"):
+            pi_client.exec("killall mixxx 2>/dev/null; true", timeout=5)
+            time.sleep(3)
+        try:
+            uf2_remote = _compile_on_pi(pi_client, fqbn, REPO_FIRMWARE)
+        except RuntimeError as e:
+            fail(str(e))
+            with Step("Restarting Mixxx"):
+                pi_client.exec("killall mixxx 2>/dev/null; true")
+            return
+        sz_r = pi_client.exec(f"stat -c%s {uf2_remote} 2>/dev/null")["stdout"].strip()
+        kb   = int(sz_r) // 1024 if sz_r.isdigit() else 0
+        ok(f"Compiled on Pi — {Path(uf2_remote).name}  ({kb} KB)")
+
+    if not flash:
+        if uf2_remote:
+            # nothing to do locally; restart Mixxx
+            with Step("Restarting Mixxx"):
+                time.sleep(2)
+                pi_client.exec("killall mixxx 2>/dev/null; true")
+        print()
+        return
+
+    # ── Flash path ──────────────────────────────────────────────────────────────
+    print()
+
+    # If compiled remotely, download UF2 locally so pico_flash() can upload it fresh
+    if uf2_remote and not uf2_local:
+        with Step("Downloading UF2 from Pi"):
+            tmp = Path(tempfile.gettempdir()) / Path(uf2_remote).name
+            tmp.write_bytes(pi_client.read_bytes(uf2_remote))
+            uf2_local = tmp
+
+    with Step("Triggering Pico bootloader"):
+        result = pico_bootloader(pi_client)
+        if "failed" in result.lower() or "error" in result.lower():
+            fail(result)
+            return
+        ok(result)
+
+    time.sleep(3)
+    print(pico_flash(pi_client, str(uf2_local)))
+    print()
diff --git a/tools/xdj_pi_dev/setup_cmds.py b/tools/xdj_pi_dev/setup_cmds.py
new file mode 100644
index 0000000..6670223
--- /dev/null
+++ b/tools/xdj_pi_dev/setup_cmds.py
@@ -0,0 +1,217 @@
+from __future__ import annotations
+
+"""
+Setup commands: SSH keys, DHCP server, hostname change, SSH recovery guide.
+
+Extracted from xdj-pi-dev.py (lines 1102-1288).
+"""
+
+import subprocess
+import textwrap
+from pathlib import Path
+
+import paramiko
+
+from xdj_pi_dev._terminal import (
+    _C, Step, section, ok, warn, fail,
+)
+
+# Project-specific SSH key (won't affect other SSH usage)
+SSH_KEY_PATH = Path.home() / ".ssh" / "xdj_pi_ed25519"
+
+
+# ─── SSH key setup ────────────────────────────────────────────────────────────
+
+def setup_ssh_keys(pi_client) -> None:
+    """
+    Generate a project-specific ed25519 key pair and install it on the Pi.
+    After this, the tool authenticates without a password.
+    """
+    section("SSH Key Setup")
+
+    # 1. Generate key locally if not present
+    if SSH_KEY_PATH.exists():
+        ok(f"Key already exists: {SSH_KEY_PATH}")
+    else:
+        print(f"  Generating ed25519 key: {SSH_KEY_PATH}")
+        r = subprocess.run(
+            ["ssh-keygen", "-t", "ed25519", "-f", str(SSH_KEY_PATH),
+             "-N", "", "-C", "xdj-pi-dev"],
+            capture_output=True, text=True
+        )
+        if r.returncode != 0:
+            fail(f"ssh-keygen failed: {r.stderr.strip()}")
+            return
+        ok(f"Key generated: {SSH_KEY_PATH}")
+
+    pub_key = (SSH_KEY_PATH.with_suffix(".pub")).read_text().strip()
+
+    # 2. Install on Pi
+    print(f"  Installing public key on Pi ({pi_client.host})…")
+    install_cmd = (
+        f"mkdir -p ~/.ssh && chmod 700 ~/.ssh && "
+        f"grep -qxF '{pub_key}' ~/.ssh/authorized_keys 2>/dev/null || "
+        f"echo '{pub_key}' >> ~/.ssh/authorized_keys && "
+        f"chmod 600 ~/.ssh/authorized_keys && echo installed"
+    )
+    r2 = pi_client.exec(install_cmd)
+    if "installed" in r2["stdout"] or r2["rc"] == 0:
+        ok("Public key installed on Pi")
+    else:
+        fail(f"Install failed: {r2['stderr'].strip()}")
+        return
+
+    # 3. Test key auth works before offering to disable password
+    print("  Testing key auth…")
+    test_ssh = paramiko.SSHClient()
+    test_ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
+    try:
+        test_ssh.connect(pi_client.host, username=pi_client.user,
+                         key_filename=str(SSH_KEY_PATH),
+                         look_for_keys=False, allow_agent=False, timeout=8)
+        test_ssh.close()
+        ok("Key auth confirmed working")
+    except Exception as e:
+        fail(f"Key auth test failed: {e}")
+        print("  Password auth is still active. Fix the key issue before disabling it.")
+        return
+
+    # 4. Offer to disable password auth (skip prompt in TUI — no stdin available)
+    from xdj_pi_dev._terminal import _tui_log_fn as _tui_fn
+    if _tui_fn:
+        ok("Key auth is working. Password auth left enabled (use CLI to disable).")
+        return
+    print()
+    print("  Key auth is working. Optionally disable SSH password auth on Pi")
+    print("  (more secure — only connections with this key will be accepted).")
+    answer = input("  Disable password auth now? [y/N] ").strip().lower()
+    if answer == "y":
+        r3 = pi_client.exec(
+            "sudo sed -i 's/^#*PasswordAuthentication.*/PasswordAuthentication no/' "
+            "/etc/ssh/sshd_config && sudo systemctl reload ssh && echo done"
+        )
+        if "done" in r3["stdout"]:
+            ok("Password auth disabled. Only key auth accepted.")
+            print()
+            print("  IMPORTANT: Keep the key file safe:")
+            print(f"    {SSH_KEY_PATH}")
+            print(f"    {SSH_KEY_PATH}.pub")
+            print()
+            print("  If you lose the key, use --restore-ssh to recover access.")
+        else:
+            fail(f"Could not update sshd_config: {r3['stderr'].strip()}")
+    else:
+        ok("Password auth left enabled (safe default)")
+
+
+# ─── SSH recovery guide ───────────────────────────────────────────────────────
+
+def restore_ssh() -> None:
+    """Print step-by-step SSH recovery instructions — no network connection required."""
+    section("SSH Recovery Guide")
+    print(textwrap.dedent("""
+    If you're locked out of the Pi (lost key, disabled password auth accidentally):
+
+    ── Option A: Physical console ─────────────────────────────────────────────
+    1. Connect a keyboard and HDMI monitor to the Pi.
+    2. Press Ctrl+Alt+F2 to switch to tty2 (away from Mixxx on tty1).
+    3. Log in: username xdj100sx, password xdj100sx
+    4. Re-enable password auth:
+         sudo nano /etc/ssh/sshd_config
+         → Change: PasswordAuthentication no → yes
+         sudo systemctl reload ssh
+    5. Press Ctrl+Alt+F1 to return to Mixxx.
+
+    ── Option B: Edit the SD card on another machine ──────────────────────────
+    1. Power off the Pi. Remove the SD card.
+    2. Mount the SD card on your machine (Linux/macOS native; Windows use DiskGenius or WSL).
+    3. Edit: /etc/ssh/sshd_config
+         → PasswordAuthentication yes
+    4. Reinstall SD card, power on Pi.
+
+    ── Option C: Install a new key without password auth ──────────────────────
+    If you have a different SSH key that still works:
+    1. ssh -i /path/to/other/key xdj100sx@<pi-ip>
+    2. Then run --setup-ssh-keys to install the project key.
+
+    ── Recovering the Pi IP if unknown ────────────────────────────────────────
+    On the Pi console:    ip addr show eth0
+    From this machine:    python3 xdj-pi-dev.py --discover
+    """))
+
+
+# ─── Pi DHCP setup ───────────────────────────────────────────────────────────
+
+def setup_pi_dhcp(pi_client) -> None:
+    """
+    Configure the Pi to act as a DHCP server on eth0.
+    After this, any machine plugged directly into the Pi gets an IP automatically
+    — no manual network alias setup needed.
+    """
+    section("Pi DHCP Server Setup")
+    print("  This installs dnsmasq on the Pi and configures it to auto-assign")
+    print("  IP addresses to machines connected via direct cable.")
+    print("  Pi's own IP stays at 192.168.10.2.")
+    print()
+
+    # Install dnsmasq
+    print("  Installing dnsmasq…")
+    r = pi_client.exec("sudo apt-get install -y dnsmasq 2>&1 | tail -3", timeout=120)
+    if r["rc"] != 0:
+        fail(f"apt-get failed: {r['stderr'].strip()}")
+        return
+    ok("dnsmasq installed")
+
+    # Write config
+    conf = textwrap.dedent("""\
+        # XDJ direct-cable DHCP — managed by xdj-pi-dev.py
+        interface=eth0
+        bind-interfaces
+        dhcp-range=192.168.10.100,192.168.10.200,255.255.255.0,12h
+        # No gateway, no DNS — pure IP assignment for direct cable
+        dhcp-option=3
+        dhcp-option=6
+    """)
+    r2 = pi_client.exec(
+        f"sudo mkdir -p /etc/dnsmasq.d && echo '{conf}' | sudo tee /etc/dnsmasq.d/xdj-direct.conf > /dev/null && echo ok"
+    )
+    if "ok" not in r2["stdout"]:
+        fail(f"Could not write dnsmasq config: {r2['stderr'].strip()}")
+        return
+    ok("dnsmasq config written (/etc/dnsmasq.d/xdj-direct.conf)")
+
+    # Enable and restart
+    r3 = pi_client.exec(
+        "sudo systemctl enable dnsmasq && sudo systemctl restart dnsmasq && echo ok"
+    )
+    if "ok" not in r3["stdout"]:
+        fail(f"dnsmasq restart failed: {r3['stderr'].strip()}")
+        return
+    ok("dnsmasq running and enabled on boot")
+
+    print()
+    print("  Done. Next time you plug in via direct cable:")
+    print("  • Your machine will get an IP in 192.168.10.100–200 automatically")
+    print("  • No manual network config needed")
+    print("  • XDJ100SX.local still works too")
+
+
+# ─── Hostname change ──────────────────────────────────────────────────────────
+
+def set_hostname(pi_client, new_hostname: str) -> None:
+    """Change the Pi's hostname and restart avahi so mDNS updates immediately."""
+    section(f"Set Hostname → {new_hostname}")
+
+    old = pi_client.exec("hostname").get("stdout", "").strip()
+    print(f"  Current hostname: {old}")
+
+    r = pi_client.exec(
+        f"sudo hostnamectl set-hostname {new_hostname} && "
+        f"sudo sed -i 's/{old}/{new_hostname}/g' /etc/hosts && "
+        f"sudo systemctl restart avahi-daemon 2>/dev/null; echo ok"
+    )
+    if "ok" in r["stdout"]:
+        ok(f"Hostname changed to: {new_hostname}")
+        print(f"  New mDNS address: {new_hostname}.local")
+    else:
+        fail(f"Failed: {r['stderr'].strip()}")
diff --git a/tools/xdj_pi_dev/signal_analyzer.py b/tools/xdj_pi_dev/signal_analyzer.py
new file mode 100644
index 0000000..37f5b76
--- /dev/null
+++ b/tools/xdj_pi_dev/signal_analyzer.py
@@ -0,0 +1,906 @@
+"""
+Signal Analyzer — live GPIO/ADC event viewer for XDJ-100SX Pico firmware.
+
+Two execution modes:
+  Web (TUI button): run_signal_analyzer_web(pi_client, stop_event, port)
+  CLI (--analyze):  run_signal_analyzer_cli(pi_client)
+
+All public functions take a pi_client as their first argument instead of
+relying on a module-level global, following Dependency Inversion.
+"""
+
+from __future__ import annotations
+
+import collections
+import re
+import sys
+import threading
+import time
+from typing import Any, Callable
+
+# ─── Pin map ─────────────────────────────────────────────────────────────────
+
+SA_PIN_NAMES: dict[int, str] = {
+     0: "EJECT",       1: "TRACK PREV",   2: "TRACK NEXT",   3: "SEARCH BACK",
+     4: "SEARCH FWD",  5: "CUE",          6: "PLAY",         7: "JET",
+     8: "ZIP",         9: "WAH",         10: "HOLD",         11: "TIME",
+    12: "MSTR TEMPO",  14: "JOG A",       15: "LED CUE",     16: "LED PLAY",
+    17: "LED INTL",    18: "LED CD",      19: "JOG B",       20: "BROWSE A",
+    21: "BROWSE B",    22: "LOAD",
+}
+SA_BUTTON_PINS = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 22]
+SA_JOG_PINS    = [14, 19]
+SA_BROWSE_PINS = [20, 21]
+SA_LED_PINS    = [15, 16, 17, 18]
+SA_ALL_PINS    = sorted(set(SA_BUTTON_PINS + SA_JOG_PINS + SA_BROWSE_PINS + SA_LED_PINS))
+
+_BOUNCE_WINDOW_US = 50_000   # 50 ms: edges within this window on same pin = bounce
+_WAVEFORM_LEN     = 40
+
+
+# ─── Shared state ─────────────────────────────────────────────────────────────
+
+class SAState:
+    """Signal-analyzer state updated by a reader thread and read by display."""
+
+    def __init__(self) -> None:
+        self.lock             = threading.Lock()
+        self.t_ref_us: int    = 0
+        self.t_latest_us: int = 0
+        self.running: bool    = False
+        self.pin_state:    dict[int, int]    = {p: 1 for p in SA_ALL_PINS}
+        self.pin_edges:    dict[int, int]    = {p: 0 for p in SA_ALL_PINS}
+        self.pin_waveform: dict[int, Any]    = {
+            p: collections.deque([1] * _WAVEFORM_LEN, maxlen=_WAVEFORM_LEN)
+            for p in SA_ALL_PINS
+        }
+        self.bounce_count:  dict[int, int]   = {p: 0 for p in SA_BUTTON_PINS}
+        self.bounce_max_us: dict[int, int]   = {p: 0 for p in SA_BUTTON_PINS}
+        self._press_t0:    dict[int, int]    = {}
+        self._press_n:     dict[int, int]    = {}
+        self._press_last:  dict[int, int]    = {}
+        self.jog_a_state = 1
+        self.jog_b_state = 1
+        self.jog_net     = 0
+        self.adc_current  = 512
+        self.adc_min      = 1023
+        self.adc_max      = 0
+        self.adc_sum      = 0.0
+        self.adc_count    = 0
+        self.adc_history: Any = collections.deque(maxlen=60)
+        self.events: Any      = collections.deque(maxlen=20)
+
+    def update_gpio(self, t_us: int, pin: int, val: int) -> None:
+        with self.lock:
+            if self.t_ref_us == 0:
+                self.t_ref_us = t_us
+            self.t_latest_us = t_us
+            self.running = True
+            if pin not in SA_ALL_PINS:
+                return
+            if val == self.pin_state.get(pin, 1):
+                return
+            self.pin_state[pin]  = val
+            self.pin_edges[pin] += 1
+            self.pin_waveform[pin].append(val)
+            rel  = t_us - self.t_ref_us
+            edge = "▔→▁" if val == 0 else "▁→▔"
+            self.events.append((rel, pin, edge))
+            if pin in SA_BUTTON_PINS:
+                self._track_bounce(pin, t_us, val)
+            if pin == 14:
+                self.jog_a_state = val
+                self.jog_net += 1 if val != self.jog_b_state else -1
+            elif pin == 19:
+                self.jog_b_state = val
+
+    def _track_bounce(self, pin: int, t_us: int, val: int) -> None:
+        if val == 0 and pin not in self._press_t0:
+            self._press_t0[pin] = self._press_last[pin] = t_us
+            self._press_n[pin]  = 1
+            return
+        if pin not in self._press_t0:
+            return
+        if t_us - self._press_last[pin] > _BOUNCE_WINDOW_US:
+            del self._press_t0[pin], self._press_n[pin], self._press_last[pin]
+            if val == 0:
+                self._press_t0[pin] = self._press_last[pin] = t_us
+                self._press_n[pin]  = 1
+            return
+        self._press_n[pin]    += 1
+        self._press_last[pin]  = t_us
+        if self._press_n[pin] > 2:
+            dur = t_us - self._press_t0[pin]
+            self.bounce_count[pin]  += 1
+            self.bounce_max_us[pin]  = max(self.bounce_max_us.get(pin, 0), dur)
+
+    def update_adc(self, t_us: int, val: int) -> None:
+        with self.lock:
+            if self.t_ref_us == 0:
+                self.t_ref_us = t_us
+            self.running     = True
+            self.adc_current = val
+            self.adc_min     = min(self.adc_min, val)
+            self.adc_max     = max(self.adc_max, val)
+            self.adc_sum    += val
+            self.adc_count  += 1
+            self.adc_history.append(val)
+
+    def reset_counters(self) -> None:
+        with self.lock:
+            for p in SA_ALL_PINS:
+                self.pin_edges[p] = 0
+                cur = self.pin_state.get(p, 1)
+                for _ in range(_WAVEFORM_LEN):
+                    self.pin_waveform[p].append(cur)
+            for p in SA_BUTTON_PINS:
+                self.bounce_count[p] = 0
+                self.bounce_max_us[p] = 0
+            self._press_t0.clear(); self._press_n.clear(); self._press_last.clear()
+            self.jog_net   = 0
+            self.adc_min   = 1023; self.adc_max = 0
+            self.adc_sum   = 0.0;  self.adc_count = 0
+            self.adc_history.clear()
+            self.events.clear()
+
+
+# ─── Protocol parsing ─────────────────────────────────────────────────────────
+
+def parse_line(line: str) -> tuple | None:
+    """Parse one SA: protocol line from Pico Core 1."""
+    if not line.startswith("SA:"):
+        return None
+    if line == "SA:START":
+        return ("start",)
+    if "ADC=" in line:
+        m = re.search(r'ADC=(\d+).*T=(\d+)', line)
+        if m:
+            return ("adc", int(m.group(1)), int(m.group(2)))
+        return None
+    m = re.search(r'T=(\d+),P=(\d+),V=(\d+)', line)
+    if m:
+        return ("gpio", int(m.group(1)), int(m.group(2)), int(m.group(3)))
+    return None
+
+
+def open_channel(pi_client: Any) -> Any:
+    """Open an SSH channel that streams /dev/ttyACM0 from the Pi."""
+    transport = pi_client._ssh.get_transport()
+    assert transport
+    ch = transport.open_session()
+    ch.set_combine_stderr(True)
+    ch.exec_command("stty -F /dev/ttyACM0 115200 raw -echo 2>/dev/null; cat /dev/ttyACM0")
+    return ch
+
+
+# ─── Web server (SSE) ─────────────────────────────────────────────────────────
+
+# Embedded HTML — kept in one place so the web UI and the Python server stay in sync.
+_WEB_HTML = r"""<!DOCTYPE html>
+<html lang="en"><head><meta charset="UTF-8">
+<title>XDJ Signal Analyzer</title>
+<style>
+:root{--bg:#0d1117;--bg2:#161b22;--bg3:#21262d;--brd:#30363d;--txt:#c9d1d9;--dim:#6e7681;--blue:#58a6ff;--grn:#3fb950;--yel:#d29922;--red:#f85149;--cyan:#39c5cf;}
+*{box-sizing:border-box;margin:0;padding:0;}
+body{background:var(--bg);color:var(--txt);font-family:'SF Mono','Fira Code','Cascadia Code',monospace;font-size:13px;overflow:hidden;height:100vh;display:flex;flex-direction:column;}
+header{background:var(--bg2);border-bottom:1px solid var(--brd);padding:7px 16px;display:flex;align-items:center;gap:14px;flex-shrink:0;}
+header h1{color:var(--blue);font-size:13px;font-weight:bold;}
+#status{font-size:12px;}#elapsed,#evcount{color:var(--dim);font-size:12px;}
+.hbtn{background:var(--bg3);border:1px solid var(--brd);color:var(--txt);padding:2px 10px;cursor:pointer;border-radius:3px;font-family:inherit;font-size:11px;margin-left:4px;}
+.hbtn:hover{border-color:var(--blue);}
+.fbar{background:var(--bg2);border-bottom:1px solid var(--brd);padding:5px 12px;display:flex;gap:6px;align-items:center;flex-shrink:0;}
+.fbtn{background:var(--bg3);border:1px solid var(--brd);color:var(--dim);padding:2px 12px;cursor:pointer;border-radius:3px;font-family:inherit;font-size:12px;}
+.fbtn.on{background:#1f6feb;border-color:#388bfd;color:#e6edf3;}
+.hint{color:var(--dim);font-size:11px;margin-left:8px;}
+.main{display:grid;grid-template-columns:1fr 270px;grid-template-rows:1fr 160px;flex:1;min-height:0;}
+.tbl-wrap{overflow-y:auto;border-right:1px solid var(--brd);}
+table{width:100%;border-collapse:collapse;}
+thead th{position:sticky;top:0;background:var(--bg2);color:var(--dim);text-align:left;padding:4px 8px;border-bottom:1px solid var(--brd);font-weight:bold;font-size:11px;text-transform:uppercase;white-space:nowrap;}
+tbody tr{border-bottom:1px solid var(--brd)22;}
+tbody tr:hover{background:#ffffff09;}
+tbody tr.sel{background:#1f6feb18;}
+tbody td{padding:3px 8px;white-space:nowrap;}
+.c-pin{color:var(--cyan);font-weight:bold;}.c-name{color:var(--dim);}
+.c-hi{color:var(--grn);}.c-lo{color:var(--yel);}
+.c-ed{color:var(--txt);}.c-bc{color:var(--red);}.c-dim{color:var(--dim);}
+.wf{letter-spacing:-1px;}
+.rpanel{display:flex;flex-direction:column;border-left:1px solid var(--brd);}
+.rsec{padding:10px 12px;border-bottom:1px solid var(--brd);flex-shrink:0;}
+.rsec.grow{flex:1;overflow:hidden;}
+.rtitle{color:var(--cyan);font-size:10px;font-weight:bold;margin-bottom:6px;letter-spacing:.5px;}
+.rcontent{font-size:12px;line-height:1.7;}
+#adc-bar-bg{background:var(--bg3);border-radius:2px;height:8px;margin:5px 0;}
+#adc-bar{height:8px;border-radius:2px;transition:width .06s;}
+#adc-nums{color:var(--dim);font-size:11px;}
+#adc-spark{color:var(--cyan);letter-spacing:-1px;font-size:11px;}
+.log-wrap{grid-column:1/-1;border-top:1px solid var(--brd);overflow-y:auto;font-size:11px;}
+.log-wrap::-webkit-scrollbar{width:4px;}.log-wrap::-webkit-scrollbar-thumb{background:var(--brd);}
+.ev{display:flex;gap:10px;padding:1px 12px;}.ev:hover{background:#ffffff06;}
+.ev-t{color:var(--dim);min-width:65px;}.ev-p{color:var(--cyan);min-width:36px;}
+.ev-n{color:var(--dim);min-width:96px;}.ev-hi{color:var(--grn);}.ev-lo{color:var(--yel);}
+.ev-bc{color:var(--red);font-size:10px;}.ev-err{color:var(--red);}
+</style></head><body>
+<header>
+  <h1>⬡ XDJ Signal Analyzer</h1>
+  <span id="status" style="color:#d29922">● connecting…</span>
+  <span id="elapsed">00:00:00</span>│
+  <span id="evcount">0 events</span>
+  <span style="margin-left:auto">
+    <button class="hbtn" onclick="resetAll()">Reset</button>
+    <button class="hbtn" onclick="clearLog()">Clear Log</button>
+  </span>
+</header>
+<div class="fbar">
+  <button class="fbtn on" id="fb-all"     onclick="setFilter('all',this)">ALL</button>
+  <button class="fbtn"    id="fb-buttons" onclick="setFilter('buttons',this)">BUTTONS</button>
+  <button class="fbtn"    id="fb-jog"     onclick="setFilter('jog',this)">JOG</button>
+  <button class="fbtn"    id="fb-leds"    onclick="setFilter('leds',this)">LEDs</button>
+  <span class="hint">click row to inspect · SSE live stream</span>
+</div>
+<div class="main">
+  <div class="tbl-wrap"><table>
+    <thead><tr><th>PIN</th><th>NAME</th><th>STATE</th><th>EDGES</th><th>BOUNCE</th><th>MAX µs</th><th>WAVEFORM</th></tr></thead>
+    <tbody id="tbody"></tbody>
+  </table></div>
+  <div class="rpanel">
+    <div class="rsec" id="det-sec">
+      <div class="rtitle">━ SELECTED PIN ━━━━━━━━━━━━━━━━━━━━━━</div>
+      <div class="rcontent" id="det" style="color:var(--dim)">↑ click a row</div>
+    </div>
+    <div class="rsec">
+      <div class="rtitle">━ JOG QUADRATURE ━━━━━━━━━━━━━━━━━━━</div>
+      <div class="rcontent" id="jog"></div>
+    </div>
+    <div class="rsec grow">
+      <div class="rtitle">━ PITCH ADC  GP26 ━━━━━━━━━━━━━━━━━━━</div>
+      <div id="adc-bar-bg"><div id="adc-bar" style="width:50%;background:var(--blue)"></div></div>
+      <div id="adc-nums"></div>
+      <div id="adc-spark"></div>
+    </div>
+  </div>
+  <div class="log-wrap"><div id="evlog"></div></div>
+</div>
+<script>
+const PIN_NAMES   = %%PIN_NAMES%%;
+const BTN_PINS    = %%BTN_PINS%%;
+const JOG_PINS    = %%JOG_PINS%%;
+const LED_PINS    = %%LED_PINS%%;
+const ALL_PINS    = %%ALL_PINS%%;
+const HOST        = "%%HOST%%";
+const FILTERS     = {all:ALL_PINS, buttons:BTN_PINS, jog:JOG_PINS, leds:LED_PINS};
+let filter = ALL_PINS, selPin = null, jogNet = 0, evCount = 0, logCount = 0, tRef = null;
+const t0 = Date.now();
+const pins = {};
+ALL_PINS.forEach(p => pins[p] = {val:1,edges:0,bounce:0,bm:0,wf:Array(24).fill(1)});
+
+function buildTable() {
+  const tb = document.getElementById('tbody');
+  tb.innerHTML = '';
+  filter.forEach(pin => {
+    const tr = document.createElement('tr');
+    tr.id = 'r'+pin; tr.onclick = ()=>selRow(pin);
+    tr.innerHTML = '<td class="c-pin">GP'+String(pin).padStart(2,'0')+'</td>'
+      +'<td class="c-name">'+(PIN_NAMES[pin]||'?')+'</td>'
+      +'<td id="st'+pin+'" class="c-hi">▔ HI</td>'
+      +'<td id="ed'+pin+'" class="c-ed">0</td>'
+      +'<td id="bc'+pin+'" class="c-dim">—</td>'
+      +'<td id="bm'+pin+'" class="c-dim">—</td>'
+      +'<td id="wf'+pin+'" class="wf c-hi">'+'▔'.repeat(24)+'</td>';
+    tb.appendChild(tr);
+  });
+}
+buildTable();
+
+function updRow(pin) {
+  const p = pins[pin];
+  const st = document.getElementById('st'+pin); if(!st)return;
+  st.textContent = p.val?'▔ HI':'▁ LO'; st.className = p.val?'c-hi':'c-lo';
+  document.getElementById('ed'+pin).textContent = p.edges;
+  const bc=document.getElementById('bc'+pin);
+  bc.textContent=p.bounce||'—'; bc.className=p.bounce?'c-bc':'c-dim';
+  const bm=document.getElementById('bm'+pin);
+  bm.textContent=p.bm||'—'; bm.className=p.bm?'c-bc':'c-dim';
+  const wf=document.getElementById('wf'+pin);
+  wf.textContent=p.wf.map(v=>v?'▔':'▁').join(''); wf.className='wf '+(p.val?'c-hi':'c-lo');
+}
+function selRow(pin) {
+  selPin=pin;
+  document.querySelectorAll('tbody tr').forEach(r=>r.classList.remove('sel'));
+  const r=document.getElementById('r'+pin); if(r)r.classList.add('sel');
+  updDet();
+}
+function updDet() {
+  if(selPin===null)return;
+  const p=pins[selPin], name=PIN_NAMES[selPin]||('GP'+selPin);
+  const sc=p.val?'var(--grn)':'var(--yel)';
+  const bc=p.bounce?`<span style="color:var(--red)">⚡ ×${p.bounce} max ${p.bm}µs</span>`:'<span style="color:var(--dim)">no bounce</span>';
+  const wf=p.wf.map(v=>v?'▔':'▁').join('');
+  document.getElementById('det').innerHTML=
+    `<div style="color:var(--cyan);font-weight:bold">GP${String(selPin).padStart(2,'0')} ${name}</div>`
+    +`<div><span style="color:${sc}">${p.val?'▔ HIGH':'▁ LOW'}</span> &nbsp;edges:<b>${p.edges}</b>&nbsp;${bc}</div>`
+    +`<div style="color:${sc};letter-spacing:-1px;margin-top:4px;font-size:12px">${wf}</div>`;
+}
+function updJog() {
+  const a=pins[14]||{val:1,wf:[],edges:0}, b=pins[19]||{val:1,wf:[],edges:0};
+  const nc=jogNet>0?'var(--grn)':jogNet<0?'var(--yel)':'var(--dim)';
+  document.getElementById('jog').innerHTML=
+    `<div><span style="color:var(--grn)">A GP14</span> <span style="color:var(--grn);letter-spacing:-1px">${a.wf.map(v=>v?'▔':'▁').join('')}</span> <span style="color:var(--dim)">e:</span>${a.edges}</div>`
+    +`<div><span style="color:var(--yel)">B GP19</span> <span style="color:var(--yel);letter-spacing:-1px">${b.wf.map(v=>v?'▔':'▁').join('')}</span> <span style="color:var(--dim)">e:</span>${b.edges}</div>`
+    +`<div style="margin-top:4px">Net: <span style="color:${nc}">${jogNet>=0?'CW':'CCW'} ${Math.abs(jogNet)}</span></div>`;
+}
+function updADC(d) {
+  const center=Math.abs(d.val-512)<=8;
+  const pct=d.val/1023*100;
+  document.getElementById('adc-bar').style.width=pct+'%';
+  document.getElementById('adc-bar').style.background=center?'var(--grn)':'var(--yel)';
+  const cs=center?'<span style="color:var(--grn)">● CENTER</span>'
+    :`<span style="color:var(--yel)">${d.val-512>0?'+':''}${d.val-512} off</span>`;
+  document.getElementById('adc-nums').innerHTML=
+    `<span style="color:var(--dim)">val:</span>${d.val} ${cs} `
+    +`<span style="color:var(--dim)">min:${d.min} max:${d.max} mean:${d.mean.toFixed(1)}</span>`;
+  if(d.hist&&d.hist.length>1){
+    const mn=Math.min(...d.hist),mx=Math.max(...d.hist),rng=mx-mn||1;
+    const ch=' ▁▂▃▄▅▆▇█';
+    document.getElementById('adc-spark').textContent=d.hist.slice(-44).map(v=>ch[Math.round((v-mn)*8/rng)]).join('');
+  }
+}
+function setFilter(name,btn) {
+  filter=FILTERS[name]||ALL_PINS;
+  document.querySelectorAll('.fbtn').forEach(b=>b.classList.remove('on'));
+  btn.classList.add('on');
+  buildTable(); filter.forEach(updRow);
+}
+function clearLog(){document.getElementById('evlog').innerHTML='';logCount=0;tRef=null;}
+function resetAll(){
+  ALL_PINS.forEach(p=>{pins[p]={val:pins[p]?.val??1,edges:0,bounce:0,bm:0,wf:Array(24).fill(pins[p]?.val??1)};updRow(p);});
+  evCount=0;jogNet=0;document.getElementById('evcount').textContent='0 events';
+  clearLog();updDet();updJog();
+}
+function addLog(ev) {
+  if(!filter.includes(ev.pin))return;
+  if(!tRef&&ev.t>0)tRef=ev.t;
+  const rel=tRef?((ev.t-tRef)/1e6).toFixed(3):'0.000';
+  const edge=ev.val?'<span class="ev-hi">▁→▔</span>':'<span class="ev-lo">▔→▁</span>';
+  const bc=ev.bounce>0?`<span class="ev-bc"> ⚡×${ev.bounce}</span>`:'';
+  const div=document.createElement('div'); div.className='ev';
+  div.innerHTML=`<span class="ev-t">${rel}s</span><span class="ev-p">GP${String(ev.pin).padStart(2,'0')}</span>`
+    +`<span class="ev-n">${PIN_NAMES[ev.pin]||''}</span>${edge}${bc}`;
+  const log=document.getElementById('evlog'); log.appendChild(div);
+  logCount++; if(logCount>500)log.removeChild(log.firstChild);
+  log.parentElement.scrollTop=log.parentElement.scrollHeight;
+}
+setInterval(()=>{
+  const el=Math.floor((Date.now()-t0)/1000);
+  document.getElementById('elapsed').textContent=
+    String(Math.floor(el/3600)).padStart(2,'0')+':'+String(Math.floor((el%3600)/60)).padStart(2,'0')+':'+String(el%60).padStart(2,'0');
+},1000);
+function connect() {
+  const es=new EventSource('/stream');
+  es.onopen=()=>{document.getElementById('status').textContent='● '+HOST;document.getElementById('status').style.color='var(--grn)';};
+  es.onmessage=e=>{
+    const ev=JSON.parse(e.data);
+    if(ev.type==='gpio'){
+      const prev=pins[ev.pin]||{};
+      pins[ev.pin]={val:ev.val,edges:ev.edges,bounce:ev.bounce,bm:ev.bounce_max_us,wf:ev.wf};
+      if(ev.pin===19&&prev.val!==undefined&&ev.val===0&&prev.val===1)
+        jogNet+=(pins[14]?.val===0)?1:-1;
+      updRow(ev.pin);
+      if(ev.pin===selPin)updDet();
+      if(ev.pin===14||ev.pin===19)updJog();
+      if(ev.t>0){evCount++;document.getElementById('evcount').textContent=evCount+' events';addLog(ev);}
+    } else if(ev.type==='adc'){
+      updADC(ev);
+    } else if(ev.type==='error'){
+      const div=document.createElement('div');div.className='ev ev-err';
+      div.textContent='⚠ '+ev.msg;document.getElementById('evlog').appendChild(div);
+      document.getElementById('status').textContent='⚠ disconnected';
+      document.getElementById('status').style.color='var(--red)';
+      es.close();setTimeout(connect,3000);
+    }
+  };
+  es.onerror=()=>{
+    document.getElementById('status').textContent='● reconnecting…';
+    document.getElementById('status').style.color='var(--yel)';
+    es.close();setTimeout(connect,3000);
+  };
+}
+updJog();connect();
+</script></body></html>"""
+
+
+def run_signal_analyzer_web(pi_client: Any, stop_event: threading.Event, port: int) -> None:
+    """HTTP + SSE server that streams GPIO/ADC events to a browser page.
+
+    Blocks until stop_event is set — run in a daemon thread.
+    """
+    import json as _json
+    import http.server
+    import socketserver
+
+    state   = SAState()
+    clients: list = []
+    clock   = threading.Lock()
+
+    def _broadcast(msg: dict) -> None:
+        data = ("data: " + _json.dumps(msg) + "\n\n").encode()
+        with clock:
+            dead = []
+            for w in list(clients):
+                try:
+                    w.write(data); w.flush()
+                except Exception:
+                    dead.append(w)
+            for w in dead:
+                clients.remove(w)
+
+    def _reader() -> None:
+        try:
+            ch  = open_channel(pi_client)
+            buf = b""
+            while not stop_event.is_set():
+                if ch.recv_ready():
+                    buf += ch.recv(4096)
+                    while b"\n" in buf:
+                        raw, buf = buf.split(b"\n", 1)
+                        parsed = parse_line(raw.decode(errors="replace").strip())
+                        if not parsed:
+                            continue
+                        if parsed[0] == "gpio":
+                            t_us, pin, val = parsed[1], parsed[2], parsed[3]
+                            state.update_gpio(t_us, pin, val)
+                            with state.lock:
+                                _broadcast({
+                                    "type": "gpio", "pin": pin, "val": val, "t": t_us,
+                                    "name": SA_PIN_NAMES.get(pin, f"GP{pin}"),
+                                    "edges": state.pin_edges.get(pin, 0),
+                                    "bounce": state.bounce_count.get(pin, 0),
+                                    "bounce_max_us": state.bounce_max_us.get(pin, 0),
+                                    "wf": list(state.pin_waveform.get(pin, []))[-24:],
+                                })
+                        elif parsed[0] == "adc":
+                            state.update_adc(parsed[2], parsed[1])
+                            with state.lock:
+                                n = state.adc_count or 1
+                                _broadcast({
+                                    "type": "adc",
+                                    "val": state.adc_current, "min": state.adc_min,
+                                    "max": state.adc_max,     "mean": state.adc_sum / n,
+                                    "hist": list(state.adc_history)[-44:],
+                                })
+                elif ch.exit_status_ready():
+                    _broadcast({"type": "error", "msg": "Serial stream closed — Pico disconnected?"})
+                    break
+                else:
+                    time.sleep(0.01)
+            ch.close()
+        except Exception as exc:
+            _broadcast({"type": "error", "msg": str(exc)})
+
+    threading.Thread(target=_reader, daemon=True).start()
+
+    html = (_WEB_HTML
+            .replace("%%PIN_NAMES%%", _json.dumps({str(k): v for k, v in SA_PIN_NAMES.items()}))
+            .replace("%%BTN_PINS%%",  _json.dumps(SA_BUTTON_PINS))
+            .replace("%%JOG_PINS%%",  _json.dumps(SA_JOG_PINS + SA_BROWSE_PINS))
+            .replace("%%LED_PINS%%",  _json.dumps(SA_LED_PINS))
+            .replace("%%ALL_PINS%%",  _json.dumps(SA_ALL_PINS))
+            .replace("%%HOST%%",      pi_client.host))
+    html_b = html.encode()
+
+    class _Handler(http.server.BaseHTTPRequestHandler):
+        def log_message(self, *_): pass
+
+        def do_GET(self) -> None:
+            if self.path in ("/", "/index.html"):
+                self.send_response(200)
+                self.send_header("Content-Type", "text/html; charset=utf-8")
+                self.send_header("Content-Length", str(len(html_b)))
+                self.end_headers()
+                self.wfile.write(html_b)
+
+            elif self.path == "/stream":
+                self.send_response(200)
+                self.send_header("Content-Type", "text/event-stream")
+                self.send_header("Cache-Control", "no-cache")
+                self.send_header("Connection", "keep-alive")
+                self.send_header("Access-Control-Allow-Origin", "*")
+                self.end_headers()
+                with state.lock:
+                    for pin in SA_ALL_PINS:
+                        snap = {
+                            "type": "gpio", "pin": pin,
+                            "val": state.pin_state.get(pin, 1), "t": 0,
+                            "name": SA_PIN_NAMES.get(pin, f"GP{pin}"),
+                            "edges": state.pin_edges.get(pin, 0),
+                            "bounce": state.bounce_count.get(pin, 0),
+                            "bounce_max_us": state.bounce_max_us.get(pin, 0),
+                            "wf": list(state.pin_waveform.get(pin, []))[-24:],
+                        }
+                        self.wfile.write(("data: " + _json.dumps(snap) + "\n\n").encode())
+                self.wfile.flush()
+                with clock:
+                    clients.append(self.wfile)
+                try:
+                    while not stop_event.is_set():
+                        time.sleep(1)
+                        self.wfile.write(b": ka\n\n")
+                        self.wfile.flush()
+                except Exception:
+                    pass
+                finally:
+                    with clock:
+                        try: clients.remove(self.wfile)
+                        except ValueError: pass
+            else:
+                self.send_error(404)
+
+    class _Server(socketserver.TCPServer):
+        allow_reuse_address = True
+
+    with _Server(("", port), _Handler) as srv:
+        srv.timeout = 0.5
+        while not stop_event.is_set():
+            srv.handle_request()
+
+
+# ─── CLI dashboard (Textual) ──────────────────────────────────────────────────
+
+def run_signal_analyzer_cli(pi_client: Any) -> None:
+    """Launch the full Textual signal analyzer dashboard (--analyze flag)."""
+    try:
+        from textual.app import App, ComposeResult
+        from textual.binding import Binding
+        from textual.containers import Horizontal, Vertical
+        from textual.widgets import Button, DataTable, Footer, RichLog, Static
+        from textual import work as _tw
+        from rich.text import Text
+    except ImportError:
+        print("textual not installed — run: pip install textual", file=sys.stderr)
+        return
+
+    chk = pi_client.exec("ls /dev/ttyACM0 2>/dev/null || echo MISSING")
+    if "MISSING" in chk["stdout"]:
+        print("/dev/ttyACM0 not found — Pico not connected or firmware not flashed", file=sys.stderr)
+        return
+
+    state  = SAState()
+    stop   = threading.Event()
+
+    FILTER_GROUPS: dict[str, list[int]] = {
+        "g-all":     SA_ALL_PINS,
+        "g-buttons": SA_BUTTON_PINS,
+        "g-jog":     SA_JOG_PINS + SA_BROWSE_PINS,
+        "g-leds":    SA_LED_PINS,
+    }
+
+    class SignalAnalyzerApp(App):  # type: ignore[misc]
+        TITLE = "XDJ Signal Analyzer"
+        CSS = """
+        Screen { background: #0d1117; color: #c9d1d9; }
+        #hdr { height: 1; padding: 0 2; background: #161b22; color: #58a6ff; content-align: left middle; }
+        #fbar { height: 3; padding: 0 1; background: #161b22; border-bottom: solid #30363d; align: left middle; }
+        .gbtn { height: 1; min-width: 11; border: solid #30363d; margin-right: 1; background: #21262d; color: #8b949e; }
+        .gbtn.-on { background: #1f6feb; color: #e6edf3; border: solid #388bfd; }
+        #fhint { color: #6e7681; margin-left: 2; }
+        #body { height: 1fr; }
+        #left  { width: 58; border-right: solid #21262d; }
+        DataTable { height: 1fr; }
+        DataTable > .datatable--header { background: #161b22; color: #8b949e; text-style: bold; }
+        DataTable > .datatable--cursor { background: #1f6feb33; }
+        DataTable > .datatable--zebra-stripe { background: #161b2244; }
+        #right { width: 1fr; padding: 0; }
+        #detail { height: 7; border-bottom: solid #21262d; padding: 1 2; background: #161b22; }
+        #jog    { height: 8; border-bottom: solid #21262d; padding: 1 2; background: #0d1117; }
+        #adc    { height: 1fr; padding: 1 2; background: #161b22; }
+        #evlog  { height: 8; border-top: solid #21262d; }
+        """
+
+        BINDINGS = [
+            Binding("q",     "quit",        "Quit"),
+            Binding("r",     "reset_all",   "Reset"),
+            Binding("l",     "clear_log",   "Clear log"),
+            Binding("space", "toggle_pin",  "Toggle"),
+            Binding("i",     "isolate_pin", "Isolate"),
+            Binding("a",     "show_all",    "All"),
+            Binding("1",     "grp1",        "Buttons"),
+            Binding("2",     "grp2",        "Jog"),
+            Binding("3",     "grp3",        "LEDs"),
+        ]
+
+        def __init__(self) -> None:
+            super().__init__()
+            self._t0         = time.time()
+            self._visible:   set[int] = set(SA_ALL_PINS)
+            self._last_chk:  dict[int, str] = {}
+
+        def compose(self) -> ComposeResult:
+            yield Static("", id="hdr")
+            with Horizontal(id="fbar"):
+                yield Button("ALL",     id="g-all",     classes="gbtn -on")
+                yield Button("BUTTONS", id="g-buttons", classes="gbtn")
+                yield Button("JOG",     id="g-jog",     classes="gbtn")
+                yield Button("LEDs",    id="g-leds",    classes="gbtn")
+                yield Static(
+                    "  ↑↓ select   [bold]Space[/]:toggle   [bold]I[/]:isolate   "
+                    "[bold]A[/]:all   [bold]1-3[/]:group   [bold]R[/]:reset   [bold]L[/]:clear log",
+                    id="fhint",
+                )
+            with Horizontal(id="body"):
+                with Vertical(id="left"):
+                    yield DataTable(id="tbl", cursor_type="row", zebra_stripes=True)
+                with Vertical(id="right"):
+                    yield Static("", id="detail")
+                    yield Static("", id="jog")
+                    yield Static("", id="adc")
+            yield RichLog(id="evlog", highlight=True, markup=True, max_lines=500)
+            yield Footer()
+
+        def on_mount(self) -> None:
+            self._rebuild_table()
+            self.set_interval(0.15, self._tick)
+            self._start_reader()
+
+        def on_worker_state_changed(self, event: object) -> None:
+            pass  # suppress app exit on unhandled worker exception
+
+        @_tw(thread=True)
+        def _start_reader(self) -> None:
+            try:
+                evlog   = self.query_one("#evlog", RichLog)
+                channel = open_channel(pi_client)
+                buf     = b""
+                while not stop.is_set():
+                    if channel.recv_ready():
+                        buf += channel.recv(4096)
+                        while b"\n" in buf:
+                            raw, buf = buf.split(b"\n", 1)
+                            parsed = parse_line(raw.decode(errors="replace").strip())
+                            if parsed is None:
+                                continue
+                            if parsed[0] == "gpio":
+                                t_us, pin, val = parsed[1], parsed[2], parsed[3]
+                                state.update_gpio(t_us, pin, val)
+                                if pin in self._visible:
+                                    self.call_from_thread(self._log_gpio, t_us, pin, val)
+                            elif parsed[0] == "adc":
+                                state.update_adc(parsed[2], parsed[1])
+                    elif channel.exit_status_ready():
+                        self.call_from_thread(
+                            evlog.write, "[red]⚠ Serial stream closed — Pico disconnected?[/]"
+                        )
+                        break
+                    else:
+                        time.sleep(0.01)
+                channel.close()
+            except Exception as exc:
+                try:
+                    self.call_from_thread(
+                        self.query_one("#evlog", RichLog).write,
+                        f"[red bold]Reader error:[/] [red]{exc}[/]",
+                    )
+                except Exception:
+                    pass
+
+        def _log_gpio(self, t_us: int, pin: int, val: int) -> None:
+            name  = SA_PIN_NAMES.get(pin, f"GP{pin}")
+            edge  = "[green]▁→▔[/]" if val else "[yellow]▔→▁[/]"
+            rel_s = (t_us - state.t_ref_us) / 1_000_000 if state.t_ref_us else 0.0
+            with state.lock:
+                bc = state.bounce_count.get(pin, 0)
+            bc_s = f"  [red bold]⚡ bounce ×{bc}[/]" if bc else ""
+            self.query_one("#evlog", RichLog).write(
+                f"[dim]{rel_s:9.3f}s[/]  [cyan]GP{pin:02d}[/]  {name:<14}  {edge}{bc_s}"
+            )
+
+        def _rebuild_table(self) -> None:
+            tbl = self.query_one("#tbl", DataTable)
+            tbl.clear(columns=True)
+            tbl.add_column("PIN",     key="pin",  width=6)
+            tbl.add_column("NAME",    key="name", width=14)
+            tbl.add_column("STATE",   key="st",   width=6)
+            tbl.add_column("EDGES",   key="ed",   width=7)
+            tbl.add_column("BOUNCE",  key="bc",   width=8)
+            tbl.add_column("MAX µs",  key="bm",   width=9)
+            tbl.add_column("WAVEFORM (last 24)", key="wf", width=26)
+            self._last_chk.clear()
+            for pin in sorted(p for p in SA_ALL_PINS if p in self._visible):
+                tbl.add_row(
+                    f"GP{pin:02d}", SA_PIN_NAMES.get(pin, "?"),
+                    "▔ HI", "0", "—", "—", "▔" * 24,
+                    key=str(pin),
+                )
+
+        def _tick(self) -> None:
+            el = time.time() - self._t0
+            hh = int(el)//3600; mm = (int(el)%3600)//60; ss = int(el)%60
+            with state.lock:
+                tot = sum(state.pin_edges.values())
+            self.query_one("#hdr", Static).update(
+                f"[bold cyan]XDJ Signal Analyzer[/]  │  [green]{pi_client.host}[/]  │  "
+                f"[dim]{hh:02d}:{mm:02d}:{ss:02d}[/]  │  total events: [bold]{tot}[/]"
+            )
+            self._update_table()
+            self._update_right()
+
+        def _update_table(self) -> None:
+            tbl  = self.query_one("#tbl", DataTable)
+            pins = sorted(p for p in SA_ALL_PINS if p in self._visible)
+            with state.lock:
+                snap = {
+                    p: (
+                        state.pin_state.get(p, 1),
+                        state.pin_edges.get(p, 0),
+                        state.bounce_count.get(p, 0),
+                        state.bounce_max_us.get(p, 0),
+                        list(state.pin_waveform.get(p, []))[-24:],
+                    )
+                    for p in pins
+                }
+            for pin in pins:
+                s_, ed, bc, bm, wf = snap[pin]
+                chk = f"{s_},{ed},{bc}"
+                if self._last_chk.get(pin) == chk:
+                    continue
+                self._last_chk[pin] = chk
+                rk   = str(pin)
+                st_c = "green" if s_ else "yellow"
+                ed_c = "bold white" if ed > 0 else "dim"
+                bc_c = "red bold" if bc > 0 else "dim"
+                wf_s = "".join("▔" if x else "▁" for x in wf)
+                try:
+                    tbl.update_cell(rk, "st", Text("▔ HI" if s_ else "▁ LO", style=st_c), update_width=False)
+                    tbl.update_cell(rk, "ed", Text(str(ed), style=ed_c),                   update_width=False)
+                    tbl.update_cell(rk, "bc", Text(str(bc) if bc else "—", style=bc_c),    update_width=False)
+                    tbl.update_cell(rk, "bm", Text(str(bm) if bm else "—", style="red" if bm else "dim"), update_width=False)
+                    tbl.update_cell(rk, "wf", Text(wf_s, style=st_c),                      update_width=False)
+                except Exception:
+                    pass
+
+        def _update_right(self) -> None:
+            tbl = self.query_one("#tbl", DataTable)
+            sel_pin: int | None = None
+            try:
+                rk = tbl.cursor_row_key
+                if rk is not None:
+                    sel_pin = int(str(rk))
+            except Exception:
+                pass
+
+            if sel_pin is not None and sel_pin in self._visible:
+                with state.lock:
+                    s_   = state.pin_state.get(sel_pin, 1)
+                    ed   = state.pin_edges.get(sel_pin, 0)
+                    bc   = state.bounce_count.get(sel_pin, 0)
+                    bm   = state.bounce_max_us.get(sel_pin, 0)
+                    wf   = list(state.pin_waveform.get(sel_pin, []))
+                name = SA_PIN_NAMES.get(sel_pin, f"GP{sel_pin}")
+                st_c = "green" if s_ else "yellow"
+                wf_s = "".join("▔" if x else "▁" for x in wf)
+                bc_s = (f"[red]⚡ bounce ×{bc}   longest: {bm} µs[/]"
+                        if bc else "[dim]no bounce detected[/]")
+                self.query_one("#detail", Static).update(
+                    f"[bold cyan]━━ GP{sel_pin:02d}  {name} ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━[/]\n"
+                    f"  [{st_c}]{'▔ HIGH' if s_ else '▁ LOW '}[/]   edges: [bold]{ed}[/]   {bc_s}\n\n"
+                    f"  [{st_c}]{wf_s}[/]"
+                )
+            else:
+                self.query_one("#detail", Static).update(
+                    "[dim]  ↑↓ navigate the table to inspect a pin[/]"
+                )
+
+            with state.lock:
+                wf_a = list(state.pin_waveform.get(14, []))
+                wf_b = list(state.pin_waveform.get(19, []))
+                a_ed = state.pin_edges.get(14, 0)
+                b_ed = state.pin_edges.get(19, 0)
+                net  = state.jog_net
+            wf_a_s = "".join("▔" if x else "▁" for x in wf_a)
+            wf_b_s = "".join("▔" if x else "▁" for x in wf_b)
+            nc  = "green" if net > 0 else ("yellow" if net < 0 else "dim")
+            ds  = "CW" if net >= 0 else "CCW"
+            self.query_one("#jog", Static).update(
+                f"[bold cyan]━━ JOG QUADRATURE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━[/]\n"
+                f"  [green]A GP14[/]  [green]{wf_a_s}[/]  [dim]edges:[/] [bold]{a_ed}[/]\n"
+                f"  [yellow]B GP19[/]  [yellow]{wf_b_s}[/]  [dim]edges:[/] [bold]{b_ed}[/]\n\n"
+                f"  Net: [{nc}]{ds} {abs(net):5d}[/] ticks   "
+                f"[dim]A:{a_ed}  B:{b_ed}  diff:{abs(a_ed - b_ed)}[/]"
+            )
+
+            with state.lock:
+                av    = state.adc_current
+                amin  = state.adc_min   if state.adc_count > 0 else 512
+                amax  = state.adc_max   if state.adc_count > 0 else 512
+                amean = (state.adc_sum / state.adc_count) if state.adc_count > 0 else 512.0
+                hist  = list(state.adc_history)
+                cnt   = state.adc_count
+            center = abs(av - 512) <= 8
+            adc_c  = "green" if center else "yellow"
+            blen   = 34
+            filled = max(0, min(blen, av * blen // 1024))
+            bar    = "█" * filled + "░" * (blen - filled)
+            spc    = " ▁▂▃▄▅▆▇█"
+            if hist and cnt > 1:
+                mn, mx = min(hist), max(hist); rng = mx - mn or 1
+                spark  = "".join(spc[int((v - mn) * 8 // rng)] for v in hist[-44:])
+            else:
+                spark  = "[dim](waiting for samples…)[/]"
+            jitter = (amax - amin) // 2 if cnt > 0 else 0
+            ctr_s  = "[green]● CENTER[/]" if center else f"[yellow]{av - 512:+d} off center[/]"
+            self.query_one("#adc", Static).update(
+                f"[bold cyan]━━ PITCH ADC  GP26/ADC0 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━[/]\n\n"
+                f"  [{adc_c}][{bar}][/]  [{adc_c}]{av:4d}[/]  {ctr_s}\n\n"
+                f"  [dim]min:[/][cyan]{amin}[/]  [dim]max:[/][cyan]{amax}[/]  "
+                f"[dim]mean:[/][cyan]{amean:.1f}[/]  "
+                f"[dim]jitter:[/][{'green' if jitter < 5 else 'yellow'}]±{jitter}[/]\n\n"
+                f"  [cyan]{spark}[/]"
+            )
+
+        def on_button_pressed(self, event: Button.Pressed) -> None:
+            bid = event.button.id
+            if bid not in FILTER_GROUPS:
+                return
+            for fid in FILTER_GROUPS:
+                self.query_one(f"#{fid}", Button).remove_class("-on")
+            event.button.add_class("-on")
+            new = set(FILTER_GROUPS[bid])
+            if new != self._visible:
+                self._visible = new
+                self._rebuild_table()
+
+        def action_toggle_pin(self) -> None:
+            tbl = self.query_one("#tbl", DataTable)
+            try:
+                pin = int(str(tbl.cursor_row_key))
+            except Exception:
+                return
+            if pin in self._visible:
+                self._visible.discard(pin)
+            else:
+                self._visible.add(pin)
+            self._rebuild_table()
+
+        def action_isolate_pin(self) -> None:
+            tbl = self.query_one("#tbl", DataTable)
+            try:
+                pin = int(str(tbl.cursor_row_key))
+            except Exception:
+                return
+            self._visible = {pin}
+            for fid in FILTER_GROUPS:
+                self.query_one(f"#{fid}", Button).remove_class("-on")
+            self._rebuild_table()
+
+        def action_show_all(self) -> None:
+            self._visible = set(SA_ALL_PINS)
+            for fid in FILTER_GROUPS:
+                self.query_one(f"#{fid}", Button).remove_class("-on")
+            self.query_one("#g-all", Button).add_class("-on")
+            self._rebuild_table()
+
+        def action_grp1(self) -> None:
+            self.query_one("#g-buttons", Button).press()
+
+        def action_grp2(self) -> None:
+            self.query_one("#g-jog", Button).press()
+
+        def action_grp3(self) -> None:
+            self.query_one("#g-leds", Button).press()
+
+        def action_clear_log(self) -> None:
+            log = self.query_one("#evlog", RichLog)
+            log.clear()
+            log.write("[dim]── log cleared ──[/]")
+
+        def action_reset_all(self) -> None:
+            state.reset_counters()
+            self._t0 = time.time()
+            self._last_chk.clear()
+            log = self.query_one("#evlog", RichLog)
+            log.clear()
+            log.write("[dim]── counters reset ──[/]")
+
+        def on_unmount(self) -> None:
+            stop.set()
+
+    SignalAnalyzerApp().run()
+    stop.set()
diff --git a/tools/xdj_pi_dev/watch.py b/tools/xdj_pi_dev/watch.py
new file mode 100644
index 0000000..6f635bf
--- /dev/null
+++ b/tools/xdj_pi_dev/watch.py
@@ -0,0 +1,267 @@
+from __future__ import annotations
+
+"""
+Watch mode: detect skin file changes and auto-deploy to Pi.
+
+Extracted from xdj-pi-dev.py (lines 1706-1863).
+"""
+
+import os
+import subprocess
+import sys
+import tempfile
+import threading
+import time
+from pathlib import Path
+
+from xdj_pi_dev._terminal import warn
+
+# ─── Module-level config ──────────────────────────────────────────────────────
+
+# Resolve relative to this file: xdj_pi_dev/ → tools/ → repo root
+_REPO_ROOT = Path(__file__).resolve().parent.parent.parent
+_PI_USER   = os.environ.get("XDJ_USER", "xdj100sx")
+
+_REPO_SKIN    = _REPO_ROOT / "mixxx" / "SKIN" / "XDJ100SX"
+_PI_SKIN      = f"/home/{_PI_USER}/.mixxx/skins/XDJ100SX"
+_PI_MIXXX_ENV = f"DISPLAY=:0 XAUTHORITY=/home/{_PI_USER}/.Xauthority"
+
+_PANELS = {
+    "hotcue":   (368, 57), "hc":  (368, 57),
+    "beatloop": (464, 57), "bl":  (464, 57),
+    "keyshift": (560, 57), "ks":  (560, 57),
+    "beatjump": (656, 57), "bj":  (656, 57),
+    "stems":    (752, 57), "st":  (752, 57),
+}
+
+_FILE_PANEL = {
+    "hotcues.xml":  "hotcue",
+    "beatloop.xml": "beatloop",
+    "keyshift.xml": "keyshift",
+    "beatjump.xml": "beatjump",
+    "stems.xml":    "stems",
+}
+
+
+# ─── Platform helpers ─────────────────────────────────────────────────────────
+
+def _tmp_path(name: str) -> Path:
+    return Path(tempfile.gettempdir()) / name
+
+
+def _open_image(path: Path) -> None:
+    """Open an image in the default viewer — macOS, Linux, Windows."""
+    s = str(path)
+    if sys.platform == "darwin":
+        subprocess.run(["open", s], check=False)
+    elif sys.platform == "win32":
+        os.startfile(s)
+    else:
+        subprocess.run(["xdg-open", s], check=False)
+
+
+# ─── Navigation / screenshot inlined ─────────────────────────────────────────
+
+def _navigate_panel(pi_client, panel_key: str) -> None:
+    key = panel_key.lower().strip()
+    coords = _PANELS.get(key)
+    if not coords:
+        return
+    x, y = coords
+    pi_client.exec(f"{_PI_MIXXX_ENV} xdotool mousemove {x} {y} click 1", timeout=5)
+    time.sleep(0.4)
+
+
+def _restart_mixxx(pi_client, panel: str | None = None) -> str:
+    pi_client.exec("killall mixxx 2>/dev/null; true")
+    time.sleep(6)
+    result = pi_client.exec("pgrep -a mixxx")
+    pid = result["stdout"].strip()
+    msg = (f"Mixxx restarted (PID {pid.split()[0]})" if pid
+           else "WARNING: Mixxx PID not found — may still be starting")
+    if panel:
+        time.sleep(1)
+        _navigate_panel(pi_client, panel)
+    return msg
+
+
+def _take_screenshot(pi_client, panel: str | None = None) -> tuple[bytes | None, str | None]:
+    """Navigate to `panel` then capture. Returns (bytes, None) or (None, error)."""
+    if panel:
+        _navigate_panel(pi_client, panel)
+    pi_client.exec("rm -f /tmp/xdj_dev_screen.png")
+    r = pi_client.exec(f"{_PI_MIXXX_ENV} scrot /tmp/xdj_dev_screen.png 2>&1", timeout=10)
+    if r["rc"] != 0:
+        return None, (r["stdout"] + r["stderr"]).strip()
+    return pi_client.read_bytes("/tmp/xdj_dev_screen.png"), None
+
+
+# ─── Deploy helper ────────────────────────────────────────────────────────────
+
+def _deploy_changes(pi_client, paths: list[str], panel: str | None, restart: bool) -> None:
+    changed_names = [Path(p).name for p in paths]
+    print(f"\n[{time.strftime('%H:%M:%S')}] Changed: {', '.join(changed_names)}")
+
+    for path in paths:
+        f = Path(path)
+        if not f.exists():
+            continue
+        remote = f"{_PI_SKIN}/{f.relative_to(_REPO_SKIN).as_posix()}"
+        pi_client.write_bytes(remote, f.read_bytes())
+        print(f"  pushed {f.name}")
+
+    target_panel = panel
+    if not target_panel:
+        for name in changed_names:
+            target_panel = _FILE_PANEL.get(name)
+            if target_panel:
+                break
+
+    if restart:
+        print("  restarting Mixxx…")
+        print(f"  {_restart_mixxx(pi_client, panel=target_panel)}")
+    else:
+        pi_client.exec(f"{_PI_MIXXX_ENV} xdotool key ctrl+F5", timeout=5)
+        time.sleep(2)
+        if target_panel:
+            _navigate_panel(pi_client, target_panel)
+
+    print("  screenshotting…")
+    data, err = _take_screenshot(pi_client, panel=None)
+    if err:
+        print(f"  screenshot failed: {err}")
+        return
+
+    out = _tmp_path("xdj_watch_screen.png")
+    out.write_bytes(data)
+    _open_image(out)
+    print(f"  screenshot → {out}")
+
+
+# ─── Public watch_mode ────────────────────────────────────────────────────────
+
+def watch_mode(pi_client, panel: str | None = None, restart: bool = False) -> None:
+    print(f"Watching {_REPO_SKIN}")
+    print("Edit any skin file — changes deploy to Pi automatically.")
+    print("Ctrl-C to stop.\n")
+
+    try:
+        from watchdog.observers import Observer
+        from watchdog.events import FileSystemEventHandler
+
+        class Handler(FileSystemEventHandler):
+            def __init__(self) -> None:
+                self.pending: dict[str, float] = {}
+
+            def on_modified(self, event) -> None:
+                if not event.is_directory:
+                    self.pending[event.src_path] = time.time()
+
+            def on_created(self, event) -> None:
+                self.on_modified(event)
+
+        handler = Handler()
+        observer = Observer()
+        observer.schedule(handler, str(_REPO_SKIN), recursive=True)
+        observer.start()
+        try:
+            while True:
+                time.sleep(0.5)
+                now   = time.time()
+                ready = [p for p, t in list(handler.pending.items()) if now - t > 0.8]
+                if not ready:
+                    continue
+                for path in ready:
+                    del handler.pending[path]
+                _deploy_changes(pi_client, ready, panel, restart)
+        finally:
+            observer.stop()
+            observer.join()
+
+    except ImportError:
+        print("(watchdog not installed — using 1s polling. pip install watchdog for faster)\n")
+        mtimes = {f: f.stat().st_mtime for f in _REPO_SKIN.rglob("*") if f.is_file()}
+        while True:
+            time.sleep(1)
+            changed = []
+            for f in _REPO_SKIN.rglob("*"):
+                if not f.is_file():
+                    continue
+                mt = f.stat().st_mtime
+                if mt != mtimes.get(f):
+                    mtimes[f] = mt
+                    changed.append(str(f))
+            if changed:
+                _deploy_changes(pi_client, changed, panel, restart)
+
+
+# ─── Stoppable watch loop (used by TUI) ──────────────────────────────────────
+
+def _watch_loop(pi_client, stop_event: threading.Event, emit=None, screenshot_fn=None) -> None:
+    """Watch skin files and push on change. Stops when stop_event is set.
+
+    screenshot_fn: optional callable(paths) invoked after each successful deploy.
+    """
+    _emit = emit or (lambda lvl, msg: None)
+    _emit("info", f"Watching {_REPO_SKIN}")
+
+    def _deploy(paths: list[str]) -> None:
+        names = [Path(p).name for p in paths]
+        _emit("info", f"Changed: {', '.join(names)}")
+        for path in paths:
+            f = Path(path)
+            if not f.exists():
+                continue
+            remote = f"{_PI_SKIN}/{f.relative_to(_REPO_SKIN).as_posix()}"
+            pi_client.write_bytes(remote, f.read_bytes())
+        _emit("ok", f"Pushed {len(paths)} file(s)")
+        if screenshot_fn:
+            try:
+                screenshot_fn(paths)
+            except Exception as _e:
+                _emit("warn", f"Screenshot: {_e}")
+
+    try:
+        from watchdog.observers import Observer
+        from watchdog.events import FileSystemEventHandler
+
+        class _Handler(FileSystemEventHandler):
+            def __init__(self) -> None:
+                self.pending: dict[str, float] = {}
+
+            def on_modified(self, event) -> None:
+                if not event.is_directory:
+                    self.pending[event.src_path] = time.time()
+
+            def on_created(self, event) -> None:
+                self.on_modified(event)
+
+        handler = _Handler()
+        observer = Observer()
+        observer.schedule(handler, str(_REPO_SKIN), recursive=True)
+        observer.start()
+        try:
+            while not stop_event.is_set():
+                time.sleep(0.5)
+                now = time.time()
+                ready = [p for p, t in list(handler.pending.items()) if now - t > 0.8]
+                if ready:
+                    for p in ready:
+                        del handler.pending[p]
+                    _deploy(ready)
+        finally:
+            observer.stop()
+            observer.join()
+    except ImportError:
+        _emit("warn", "watchdog not installed — using 1s polling")
+        mtimes = {f: f.stat().st_mtime for f in _REPO_SKIN.rglob("*") if f.is_file()}
+        while not stop_event.is_set():
+            time.sleep(1)
+            changed = [
+                str(f) for f in _REPO_SKIN.rglob("*")
+                if f.is_file() and f.stat().st_mtime != mtimes.get(f)
+            ]
+            for f in [Path(p) for p in changed]:
+                mtimes[f] = f.stat().st_mtime
+            if changed:
+                _deploy(changed)