diff --git a/.gitignore b/.gitignore
index 0595b084..e5aa1a81 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
 # Build directory (out-of-tree build)
 /build/
+tools/chatgui/build/
 
 # Build outputs
 *.o
diff --git a/tools/chatgui/CMakeLists.txt b/tools/chatgui/CMakeLists.txt
new file mode 100644
index 00000000..37d10ebd
--- /dev/null
+++ b/tools/chatgui/CMakeLists.txt
@@ -0,0 +1,27 @@
+cmake_minimum_required(VERSION 3.16)
+project(chatgui VERSION 0.1.0 LANGUAGES CXX)
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+set(CMAKE_AUTOMOC ON)
+
+find_package(Qt5 COMPONENTS Widgets QUIET)
+if(NOT Qt5_FOUND)
+    find_package(Qt6 COMPONENTS Widgets REQUIRED)
+    set(QT_LIBS Qt6::Widgets)
+else()
+    set(QT_LIBS Qt5::Widgets)
+endif()
+
+add_executable(chatgui
+    src/main.cpp
+    src/mainwindow.cpp
+    src/channellist.cpp
+    src/channeldelegate.cpp
+    src/chatview.cpp
+    src/messagedelegate.cpp
+    src/messagelist.cpp
+    src/accountlist.cpp
+)
+
+target_link_libraries(chatgui PRIVATE ${QT_LIBS})
diff --git a/tools/chatgui/build.bat b/tools/chatgui/build.bat
new file mode 100644
index 00000000..15c76363
--- /dev/null
+++ b/tools/chatgui/build.bat
@@ -0,0 +1,42 @@
+@echo off
+pushd "%~dp0\..\.."
+
+echo ChatGUI Build Script for MSYS2 UCRT64
+echo ===========================================
+echo.
+
+set MSYS2_PATH=C:\msys64
+if not "%MSYS2_ROOT%"=="" set MSYS2_PATH=%MSYS2_ROOT%
+if not "%MSYS2%"=="" set MSYS2_PATH=%MSYS2%
+
+if not exist "%MSYS2_PATH%\msys2_shell.cmd" (
+    echo [ERROR] MSYS2 not found at %MSYS2_PATH%
+    echo Please install MSYS2 from https://www.msys2.org/
+    echo or set MSYS2_ROOT environment variable.
+    pause
+    exit /b 1
+)
+
+echo [INFO] MSYS2 found at: %MSYS2_PATH%
+echo [INFO] Starting build...
+echo.
+
+set "CURRENT_DIR=%CD%"
+
+call "%MSYS2_PATH%\msys2_shell.cmd" -ucrt64 -here -defterm -no-start -c "cd \"%CURRENT_DIR%/tools/chatgui\" && bash build.sh 2>&1 | tee build_win.log"
+
+set BUILD_RESULT=%ERRORLEVEL%
+
+echo.
+echo ===========================================
+if %BUILD_RESULT% == 0 (
+    echo [SUCCESS] Build completed!
+    echo [INFO] Executable: tools\chatgui\build\chatgui.exe
+) else (
+    echo [FAILED] Build failed with error code: %BUILD_RESULT%
+    echo [INFO] Check tools\chatgui\build_win.log for details
+)
+echo ===========================================
+echo.
+
+pause
diff --git a/tools/chatgui/build.sh b/tools/chatgui/build.sh
new file mode 100755
index 00000000..83d2794d
--- /dev/null
+++ b/tools/chatgui/build.sh
@@ -0,0 +1,44 @@
+#!/bin/bash
+set -eo pipefail
+
+LOG_FILE="build_win.log"
+> "$LOG_FILE"
+
+log() { echo "$1"; echo "$1" >> "$LOG_FILE"; }
+
+log "================================"
+log "ChatGUI Build Script (MSYS2 UCRT64)"
+log "================================"
+log ""
+
+SRC_DIR="$(cd "$(dirname "$0")" && pwd)"
+BUILD_DIR="$SRC_DIR/build"
+
+log "Source:  $SRC_DIR"
+log "Build:   $BUILD_DIR"
+log ""
+
+log "[1/3] Configuring CMake..."
+cmake -S "$SRC_DIR" -B "$BUILD_DIR" -G "MSYS Makefiles" 2>&1 | tee -a "$LOG_FILE"
+test ${PIPESTATUS[0]} -eq 0 || { log "CMake configure FAILED"; exit 1; }
+
+log ""
+log "[2/3] Building..."
+cmake --build "$BUILD_DIR" 2>&1 | tee -a "$LOG_FILE"
+test ${PIPESTATUS[0]} -eq 0 || { log "Build FAILED"; exit 1; }
+
+log ""
+log "[3/3] Verifying..."
+EXE="$BUILD_DIR/chatgui.exe"
+if [ -f "$EXE" ]; then
+    SIZE=$(du -h "$EXE" | cut -f1)
+    log "  OK: chatgui.exe ($SIZE)"
+    log ""
+    log "================================"
+    log "Build SUCCESS"
+    log "================================"
+    log "Executable: $EXE"
+else
+    log "  FAIL: chatgui.exe not found"
+    exit 1
+fi
diff --git a/tools/chatgui/resources/bg.jpg b/tools/chatgui/resources/bg.jpg
new file mode 100644
index 00000000..5b95d805
Binary files /dev/null and b/tools/chatgui/resources/bg.jpg differ
diff --git a/tools/chatgui/src/accountlist.cpp b/tools/chatgui/src/accountlist.cpp
new file mode 100644
index 00000000..686ff7d3
--- /dev/null
+++ b/tools/chatgui/src/accountlist.cpp
@@ -0,0 +1,69 @@
+#include "accountlist.h"
+#include <QVBoxLayout>
+#include <QLabel>
+#include <QPainter>
+#include <QPixmap>
+
+static QPixmap makeAvatar(const QColor &color, const QString &letter) {
+    QPixmap pix(24, 24);
+    pix.fill(Qt::transparent);
+    QPainter p(&pix);
+    p.setRenderHint(QPainter::Antialiasing);
+    p.setBrush(color);
+    p.setPen(Qt::NoPen);
+    p.drawEllipse(0, 0, 24, 24);
+    p.setPen(Qt::white);
+    QFont f = p.font();
+    f.setBold(true);
+    f.setPointSize(10);
+    p.setFont(f);
+    p.drawText(QRect(0, 0, 24, 24), Qt::AlignCenter, letter);
+    p.end();
+    return pix;
+}
+
+AccountList::AccountList(QWidget *parent)
+    : QWidget(parent)
+    , m_listView(new QListView(this))
+    , m_model(new QStandardItemModel(this))
+{
+    auto *layout = new QVBoxLayout(this);
+    layout->setContentsMargins(0, 0, 0, 0);
+    layout->setSpacing(0);
+
+    auto *header = new QLabel("Accounts", this);
+    header->setAlignment(Qt::AlignCenter);
+    header->setStyleSheet("font-weight: bold; padding: 8px; background: palette(window);");
+    layout->addWidget(header);
+
+    m_listView->setModel(m_model);
+    m_listView->setEditTriggers(QAbstractItemView::NoEditTriggers);
+    m_listView->setSelectionMode(QAbstractItemView::SingleSelection);
+    m_listView->setIconSize(QSize(24, 24));
+    m_listView->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+    m_listView->setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
+    layout->addWidget(m_listView);
+
+    populateStubData();
+}
+
+void AccountList::populateStubData() {
+    struct {
+        const char *name;
+        QColor color;
+        const char *letter;
+    } accounts[] = {
+        {"Alice",    QColor(74, 144, 226), "A"},
+        {"Bob",      QColor(126, 211, 33), "B"},
+        {"Carol",    QColor(245, 166, 35), "C"},
+        {"Dave",     QColor(144, 19, 254), "D"},
+        {"Eve",      QColor(0, 184, 148),  "E"},
+    };
+
+    for (const auto &a : accounts) {
+        auto *item = new QStandardItem();
+        item->setText(a.name);
+        item->setIcon(QIcon(makeAvatar(a.color, a.letter)));
+        m_model->appendRow(item);
+    }
+}
diff --git a/tools/chatgui/src/accountlist.h b/tools/chatgui/src/accountlist.h
new file mode 100644
index 00000000..7fc1cfc0
--- /dev/null
+++ b/tools/chatgui/src/accountlist.h
@@ -0,0 +1,16 @@
+#pragma once
+
+#include <QWidget>
+#include <QListView>
+#include <QStandardItemModel>
+
+class AccountList : public QWidget {
+    Q_OBJECT
+public:
+    explicit AccountList(QWidget *parent = nullptr);
+
+private:
+    QListView *m_listView;
+    QStandardItemModel *m_model;
+    void populateStubData();
+};
diff --git a/tools/chatgui/src/channeldelegate.cpp b/tools/chatgui/src/channeldelegate.cpp
new file mode 100644
index 00000000..daefcb56
--- /dev/null
+++ b/tools/chatgui/src/channeldelegate.cpp
@@ -0,0 +1,74 @@
+#include "channeldelegate.h"
+#include <QPainter>
+#include <QApplication>
+
+ChannelDelegate::ChannelDelegate(QObject *parent)
+    : QStyledItemDelegate(parent) {}
+
+void ChannelDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
+                            const QModelIndex &index) const {
+    painter->save();
+
+    if (option.state & QStyle::State_Selected) {
+        painter->fillRect(option.rect, option.palette.highlight());
+    } else if (option.state & QStyle::State_MouseOver) {
+        painter->fillRect(option.rect, option.palette.light());
+    }
+
+    const int margin = 8;
+    const int iconSize = 32;
+    QRect iconRect(option.rect.left() + margin,
+                   option.rect.top() + (option.rect.height() - iconSize) / 2,
+                   iconSize, iconSize);
+
+    QIcon icon = qvariant_cast<QIcon>(index.data(ChannelIconRole));
+    if (!icon.isNull()) {
+        icon.paint(painter, iconRect);
+    }
+
+    QRect textRect(iconRect.right() + margin, option.rect.top() + margin,
+                   option.rect.right() - iconRect.right() - 2 * margin,
+                   option.rect.height() - 2 * margin);
+
+    QString name = index.data(ChannelNameRole).toString();
+    QFont nameFont = option.font;
+    nameFont.setBold(true);
+    nameFont.setPointSize(nameFont.pointSize() + 1);
+    painter->setFont(nameFont);
+
+    QColor textColor = (option.state & QStyle::State_Selected)
+                       ? option.palette.highlightedText().color()
+                       : option.palette.text().color();
+    painter->setPen(textColor);
+
+    QRect nameRect = textRect;
+    nameRect.setHeight(QFontMetrics(nameFont).height());
+    painter->drawText(nameRect, Qt::AlignLeft | Qt::AlignTop,
+                      painter->fontMetrics().elidedText(name, Qt::ElideRight, nameRect.width()));
+
+    QString lastMsg = index.data(ChannelLastMessageRole).toString();
+    if (!lastMsg.isEmpty()) {
+        QFont msgFont = option.font;
+        msgFont.setPointSize(msgFont.pointSize() - 1);
+        painter->setFont(msgFont);
+
+        QColor msgColor = (option.state & QStyle::State_Selected)
+                          ? option.palette.highlightedText().color().darker(120)
+                          : QColor(128, 128, 128);
+        painter->setPen(msgColor);
+
+        QRect msgRect(textRect.left(), nameRect.bottom() + 4,
+                      textRect.width(), option.rect.bottom() - nameRect.bottom() - margin);
+        QString elidedMsg = painter->fontMetrics().elidedText(lastMsg, Qt::ElideRight, msgRect.width());
+        painter->drawText(msgRect, Qt::AlignLeft | Qt::AlignTop | Qt::TextWordWrap, elidedMsg);
+    }
+
+    painter->restore();
+}
+
+QSize ChannelDelegate::sizeHint(const QStyleOptionViewItem &option,
+                                const QModelIndex &index) const {
+    Q_UNUSED(option);
+    Q_UNUSED(index);
+    return QSize(200, 56);
+}
diff --git a/tools/chatgui/src/channeldelegate.h b/tools/chatgui/src/channeldelegate.h
new file mode 100644
index 00000000..8bfa7324
--- /dev/null
+++ b/tools/chatgui/src/channeldelegate.h
@@ -0,0 +1,20 @@
+#pragma once
+
+#include <QStyledItemDelegate>
+
+enum ChannelDataRole {
+    ChannelNameRole = Qt::DisplayRole,
+    ChannelIconRole = Qt::DecorationRole,
+    ChannelLastMessageRole = Qt::UserRole + 1
+};
+
+class ChannelDelegate : public QStyledItemDelegate {
+    Q_OBJECT
+public:
+    explicit ChannelDelegate(QObject *parent = nullptr);
+
+    void paint(QPainter *painter, const QStyleOptionViewItem &option,
+               const QModelIndex &index) const override;
+    QSize sizeHint(const QStyleOptionViewItem &option,
+                   const QModelIndex &index) const override;
+};
diff --git a/tools/chatgui/src/channellist.cpp b/tools/chatgui/src/channellist.cpp
new file mode 100644
index 00000000..7885b1da
--- /dev/null
+++ b/tools/chatgui/src/channellist.cpp
@@ -0,0 +1,82 @@
+#include "channellist.h"
+#include "channeldelegate.h"
+#include <QVBoxLayout>
+#include <QLabel>
+#include <QPainter>
+#include <QPixmap>
+
+static QIcon makeChannelIcon(const QColor &color, const QString &letter) {
+    QPixmap pix(32, 32);
+    pix.fill(Qt::transparent);
+    QPainter p(&pix);
+    p.setRenderHint(QPainter::Antialiasing);
+    p.setBrush(color);
+    p.setPen(Qt::NoPen);
+    p.drawRoundedRect(0, 0, 32, 32, 8, 8);
+    p.setPen(Qt::white);
+    QFont f = p.font();
+    f.setBold(true);
+    f.setPointSize(14);
+    p.setFont(f);
+    p.drawText(QRect(0, 0, 32, 32), Qt::AlignCenter, letter);
+    p.end();
+    return QIcon(pix);
+}
+
+ChannelList::ChannelList(QWidget *parent)
+    : QWidget(parent)
+    , m_listView(new QListView(this))
+    , m_model(new QStandardItemModel(this))
+{
+    auto *layout = new QVBoxLayout(this);
+    layout->setContentsMargins(0, 0, 0, 0);
+    layout->setSpacing(0);
+
+    auto *header = new QLabel("Channels", this);
+    header->setAlignment(Qt::AlignCenter);
+    header->setStyleSheet("font-weight: bold; padding: 8px; background: palette(window);");
+    layout->addWidget(header);
+
+    m_listView->setModel(m_model);
+    m_listView->setItemDelegate(new ChannelDelegate(this));
+    m_listView->setEditTriggers(QAbstractItemView::NoEditTriggers);
+    m_listView->setSelectionMode(QAbstractItemView::SingleSelection);
+    m_listView->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+    m_listView->setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
+    layout->addWidget(m_listView);
+
+    connect(m_listView->selectionModel(), &QItemSelectionModel::currentChanged,
+            this, [this](const QModelIndex &current, const QModelIndex &) {
+                if (current.isValid()) {
+                    emit channelSelected(current.row());
+                }
+            });
+
+    populateStubData();
+}
+
+void ChannelList::populateStubData() {
+    struct {
+        const char *name;
+        const char *lastMsg;
+        QColor color;
+        const char *letter;
+    } channels[] = {
+        {"#general",     "Alice: Sounds good, let's deploy tomorrow morning.", QColor(74, 144, 226), "G"},
+        {"#random",      "Bob: Anyone seen the latest episode? It was amazing!", QColor(126, 211, 33), "R"},
+        {"#dev-team",    "Carol: I've pushed the fix for ETCP-42 to staging.",   QColor(245, 166, 35), "D"},
+        {"#announcements","Admin: Maintenance scheduled for Sunday 02:00 UTC.",  QColor(208, 2, 27),  "A"},
+        {"#support",     "Dave: Can someone help me configure the routing table? The BGP session keeps dropping after the handshake completes. I've checked the logs.", QColor(144, 19, 254), "S"},
+        {"#offtopic",    "Eve: Check out this new keyboard — Cherry MX Blue, 60%.", QColor(0, 184, 148), "O"},
+    };
+
+    for (const auto &ch : channels) {
+        auto *item = new QStandardItem();
+        item->setData(ch.name, ChannelNameRole);
+        item->setData(QString::fromUtf8(ch.lastMsg), ChannelLastMessageRole);
+        item->setData(makeChannelIcon(ch.color, ch.letter), ChannelIconRole);
+        m_model->appendRow(item);
+    }
+
+    m_listView->setCurrentIndex(m_model->index(0, 0));
+}
diff --git a/tools/chatgui/src/channellist.h b/tools/chatgui/src/channellist.h
new file mode 100644
index 00000000..6f81f9eb
--- /dev/null
+++ b/tools/chatgui/src/channellist.h
@@ -0,0 +1,19 @@
+#pragma once
+
+#include <QWidget>
+#include <QListView>
+#include <QStandardItemModel>
+
+class ChannelList : public QWidget {
+    Q_OBJECT
+public:
+    explicit ChannelList(QWidget *parent = nullptr);
+
+signals:
+    void channelSelected(int index);
+
+private:
+    QListView *m_listView;
+    QStandardItemModel *m_model;
+    void populateStubData();
+};
diff --git a/tools/chatgui/src/chatview.cpp b/tools/chatgui/src/chatview.cpp
new file mode 100644
index 00000000..cb4dbb68
--- /dev/null
+++ b/tools/chatgui/src/chatview.cpp
@@ -0,0 +1,34 @@
+#include "chatview.h"
+#include <QPainter>
+#include <QDebug>
+
+ChatView::ChatView(QWidget *parent)
+    : QListView(parent)
+{
+}
+
+void ChatView::setBackgroundImage(const QString &path) {
+    if (!m_background.load(path)) {
+        qWarning() << "ChatView: failed to load background" << path;
+        return;
+    }
+    viewport()->update();
+}
+
+void ChatView::resizeEvent(QResizeEvent *event) {
+    QListView::resizeEvent(event);
+    scheduleDelayedItemsLayout();
+}
+
+void ChatView::scrollContentsBy(int dx, int dy) {
+    QListView::scrollContentsBy(dx, dy);
+    viewport()->update();
+}
+
+void ChatView::paintEvent(QPaintEvent *event) {
+    if (!m_background.isNull()) {
+        QPainter p(viewport());
+        p.drawTiledPixmap(viewport()->rect(), m_background);
+    }
+    QListView::paintEvent(event);
+}
diff --git a/tools/chatgui/src/chatview.h b/tools/chatgui/src/chatview.h
new file mode 100644
index 00000000..3de619b6
--- /dev/null
+++ b/tools/chatgui/src/chatview.h
@@ -0,0 +1,19 @@
+#pragma once
+
+#include <QListView>
+
+class ChatView : public QListView {
+    Q_OBJECT
+public:
+    explicit ChatView(QWidget *parent = nullptr);
+
+    void setBackgroundImage(const QString &path);
+
+protected:
+    void paintEvent(QPaintEvent *event) override;
+    void resizeEvent(QResizeEvent *event) override;
+    void scrollContentsBy(int dx, int dy) override;
+
+private:
+    QPixmap m_background;
+};
diff --git a/tools/chatgui/src/main.cpp b/tools/chatgui/src/main.cpp
new file mode 100644
index 00000000..5df4f1f9
--- /dev/null
+++ b/tools/chatgui/src/main.cpp
@@ -0,0 +1,13 @@
+#include <QApplication>
+#include "mainwindow.h"
+
+int main(int argc, char *argv[]) {
+    QApplication app(argc, argv);
+    app.setApplicationName("Chat");
+    app.setQuitOnLastWindowClosed(false);
+
+    MainWindow w;
+    w.show();
+
+    return app.exec();
+}
diff --git a/tools/chatgui/src/mainwindow.cpp b/tools/chatgui/src/mainwindow.cpp
new file mode 100644
index 00000000..88dcdd20
--- /dev/null
+++ b/tools/chatgui/src/mainwindow.cpp
@@ -0,0 +1,83 @@
+#include "mainwindow.h"
+#include "channellist.h"
+#include "messagelist.h"
+#include "accountlist.h"
+#include <QSplitter>
+#include <QCloseEvent>
+#include <QApplication>
+#include <QStyle>
+
+MainWindow::MainWindow(QWidget *parent)
+    : QMainWindow(parent)
+    , m_channelList(nullptr)
+    , m_messageList(nullptr)
+    , m_accountList(nullptr)
+    , m_trayIcon(nullptr)
+    , m_trayMenu(nullptr)
+{
+    setWindowTitle("Chat");
+    resize(900, 600);
+
+    setupUi();
+    setupTray();
+}
+
+void MainWindow::setupUi() {
+    auto *splitter = new QSplitter(Qt::Horizontal, this);
+
+    m_channelList = new ChannelList(splitter);
+    m_messageList = new MessageList(splitter);
+    m_accountList = new AccountList(splitter);
+
+    splitter->addWidget(m_channelList);
+    splitter->addWidget(m_messageList);
+    splitter->addWidget(m_accountList);
+
+    splitter->setStretchFactor(0, 2);
+    splitter->setStretchFactor(1, 5);
+    splitter->setStretchFactor(2, 1);
+
+    splitter->setSizes({220, 480, 180});
+
+    setCentralWidget(splitter);
+}
+
+void MainWindow::setupTray() {
+    m_trayIcon = new QSystemTrayIcon(this);
+    m_trayIcon->setIcon(style()->standardIcon(QStyle::SP_ComputerIcon));
+    m_trayIcon->setToolTip("Chat");
+
+    m_trayMenu = new QMenu(this);
+    QAction *showAction = m_trayMenu->addAction("Show");
+    connect(showAction, &QAction::triggered, this, [this]() {
+        show();
+        raise();
+        activateWindow();
+    });
+
+    QAction *quitAction = m_trayMenu->addAction("Quit");
+    connect(quitAction, &QAction::triggered, qApp, &QApplication::quit);
+
+    m_trayIcon->setContextMenu(m_trayMenu);
+
+    connect(m_trayIcon, &QSystemTrayIcon::activated,
+            this, &MainWindow::onTrayActivated);
+
+    m_trayIcon->show();
+}
+
+void MainWindow::closeEvent(QCloseEvent *event) {
+    hide();
+    m_trayIcon->showMessage("Chat", "Application minimized to tray.",
+                            QSystemTrayIcon::Information, 2000);
+    event->ignore();
+}
+
+void MainWindow::onTrayActivated(QSystemTrayIcon::ActivationReason reason) {
+    if (reason == QSystemTrayIcon::Trigger ||
+        reason == QSystemTrayIcon::DoubleClick) {
+        show();
+        raise();
+        activateWindow();
+    }
+}
diff --git a/tools/chatgui/src/mainwindow.h b/tools/chatgui/src/mainwindow.h
new file mode 100644
index 00000000..bc2401d3
--- /dev/null
+++ b/tools/chatgui/src/mainwindow.h
@@ -0,0 +1,32 @@
+#pragma once
+
+#include <QMainWindow>
+#include <QSystemTrayIcon>
+#include <QMenu>
+
+class ChannelList;
+class MessageList;
+class AccountList;
+
+class MainWindow : public QMainWindow {
+    Q_OBJECT
+public:
+    explicit MainWindow(QWidget *parent = nullptr);
+    ~MainWindow() override = default;
+
+protected:
+    void closeEvent(QCloseEvent *event) override;
+
+private slots:
+    void onTrayActivated(QSystemTrayIcon::ActivationReason reason);
+
+private:
+    void setupUi();
+    void setupTray();
+
+    ChannelList   *m_channelList;
+    MessageList   *m_messageList;
+    AccountList   *m_accountList;
+    QSystemTrayIcon *m_trayIcon;
+    QMenu           *m_trayMenu;
+};
diff --git a/tools/chatgui/src/messagedelegate.cpp b/tools/chatgui/src/messagedelegate.cpp
new file mode 100644
index 00000000..ae0d5b4d
--- /dev/null
+++ b/tools/chatgui/src/messagedelegate.cpp
@@ -0,0 +1,251 @@
+#include "messagedelegate.h"
+#include <QPainter>
+#include <QPainterPath>
+#include <QApplication>
+#include <QAbstractItemView>
+#include <QFontMetrics>
+
+MessageDelegate::MessageDelegate(QObject *parent)
+    : QStyledItemDelegate(parent) {}
+
+QSize MessageDelegate::sizeHint(const QStyleOptionViewItem &option,
+                                const QModelIndex &index) const {
+    Layout L = calcLayout(option, index);
+    return QSize(L.viewWidth, L.totalHeight);
+}
+
+static int measureTextHeight(const QFont &font, const QString &text, int width) {
+    if (text.isEmpty() || width <= 0) return 0;
+    QRect r = QFontMetrics(font).boundingRect(QRect(0, 0, width, 100000),
+                                               Qt::AlignLeft | Qt::TextWordWrap, text);
+    return r.height();
+}
+
+MessageDelegate::Layout MessageDelegate::calcLayout(
+    const QStyleOptionViewItem &option, const QModelIndex &index) const
+{
+    Layout L{};
+    L.viewWidth = 300;
+    if (option.widget) {
+        auto *v = qobject_cast<const QAbstractItemView *>(option.widget);
+        if (v) L.viewWidth = v->viewport()->width();
+    }
+    if (L.viewWidth <= 0) L.viewWidth = 300;
+
+    bool hasQuote = index.data(MsgHasQuoteRole).toBool();
+    QString text  = index.data(MsgTextRole).toString();
+    QString qText = hasQuote ? index.data(MsgQuoteTextRole).toString() : QString();
+
+    int bubbleW = L.viewWidth - kMarginH - kAvatar - kGap - kMarginH;
+    if (bubbleW < 100) bubbleW = 100;
+    L.bubbleWidth = bubbleW;
+
+    int textW = bubbleW - 2 * kPadH;
+
+    int qH = 0;
+    if (hasQuote) {
+        int qTextW = bubbleW - 2 * kPadH - kQuoteBarW - kQuotePadH;
+        int qTextH = measureTextHeight(option.font, qText, qTextW);
+        int qOneLineH = QFontMetrics(option.font).height();
+        qH = kQuotePadV + qOneLineH + (qText.isEmpty() ? 0 : 2 + qTextH) + kQuotePadV;
+    }
+
+    int textH = measureTextHeight(option.font, text, textW);
+    int bubbleH = kPadTop + (hasQuote ? qH + kQuoteGap : 0) + textH + kStatusH + kPadBot;
+    L.totalHeight = qMax(bubbleH, kAvatar) + kItemGap;
+
+    int contentLeft = kMarginH + kAvatar + kGap;
+
+    L.bubbleRect = QRect(contentLeft, 0, bubbleW, bubbleH);
+
+    int contentTop = kPadTop;
+
+    if (hasQuote) {
+        L.quoteRect = QRect(contentLeft + kPadH, contentTop, bubbleW - 2 * kPadH, qH);
+        L.quoteBarRect = QRect(L.quoteRect.left(), L.quoteRect.top(),
+                               kQuoteBarW, qH);
+        int tx = L.quoteBarRect.right() + kQuotePadH;
+        L.quoteAuthorRect = QRect(tx, L.quoteRect.top() + kQuotePadV,
+                                  L.quoteRect.width() - kQuoteBarW - kQuotePadH,
+                                  QFontMetrics(option.font).height());
+        L.quoteTextRect = QRect(tx,
+                                L.quoteAuthorRect.bottom() + 2,
+                                L.quoteAuthorRect.width(),
+                                qH - kQuotePadV - QFontMetrics(option.font).height() - 2 - kQuotePadV);
+        contentTop += qH + kQuoteGap;
+    }
+
+    L.textRect   = QRect(contentLeft + kPadH, contentTop,
+                          textW, textH);
+    L.statusRect = QRect(contentLeft + kPadH,
+                          contentTop + textH + 2,
+                          textW, kStatusH);
+
+    int avatarY = L.bubbleRect.bottom() - kAvatar;
+    L.avatarRect = QRect(kMarginH, avatarY, kAvatar, kAvatar);
+
+    return L;
+}
+
+void MessageDelegate::paint(QPainter *painter, const QStyleOptionViewItem &option,
+                            const QModelIndex &index) const {
+    painter->save();
+    painter->translate(option.rect.topLeft());
+    painter->setClipRect(QRect(QPoint(0, 0), option.rect.size()));
+
+    Layout L = calcLayout(option, index);
+
+    drawBubble(painter, L);
+
+    if (index.data(MsgHasQuoteRole).toBool()) {
+        drawQuote(painter, L, index, option);
+    }
+
+    drawAvatar(painter, L, index);
+
+    painter->setPen(option.palette.text().color());
+    QFont textFont = option.font;
+    textFont.setPointSize(textFont.pointSize());
+    painter->setFont(textFont);
+    painter->drawText(L.textRect, Qt::AlignLeft | Qt::TextWordWrap,
+                      index.data(MsgTextRole).toString());
+
+    drawStatusBar(painter, L, index, option);
+
+    painter->restore();
+}
+
+void MessageDelegate::drawQuote(QPainter *p, const Layout &L,
+                                const QModelIndex &index,
+                                const QStyleOptionViewItem &opt) const {
+    p->save();
+
+    p->setPen(Qt::NoPen);
+    p->setBrush(QColor(0xFF, 0xEE, 0xEE));
+    p->drawRoundedRect(L.quoteRect, 5, 5);
+
+    p->setPen(Qt::NoPen);
+    p->setBrush(QColor(0xE0, 0x40, 0x40));
+    p->drawRect(L.quoteBarRect);
+
+    QFont boldFont = opt.font;
+    boldFont.setBold(true);
+    p->setFont(boldFont);
+    p->setPen(QColor(0xE0, 0x40, 0x40));
+    p->drawText(L.quoteAuthorRect, Qt::AlignLeft | Qt::AlignVCenter,
+                index.data(MsgQuoteAuthorRole).toString());
+
+    p->setFont(opt.font);
+    p->setPen(QColor(0x99, 0x55, 0x55));
+    p->drawText(L.quoteTextRect, Qt::AlignLeft | Qt::TextWordWrap,
+                index.data(MsgQuoteTextRole).toString());
+
+    p->restore();
+}
+
+void MessageDelegate::drawBubble(QPainter *p, const Layout &L) const {
+    p->save();
+    p->setRenderHint(QPainter::Antialiasing);
+
+    QRectF b = L.bubbleRect;
+    qreal r = kRadius;
+    qreal t = kTail;
+
+    QPainterPath body;
+    body.addRoundedRect(b, r, r);
+
+    QPainterPath tail;
+    qreal tx = b.left();
+    qreal ty = b.bottom();
+    tail.moveTo(tx, ty - r);
+    tail.lineTo(tx - t, ty - t / 2.0);
+    tail.lineTo(tx + r, ty);
+    tail.closeSubpath();
+
+    QPainterPath combined = body.united(tail);
+
+    p->setPen(QPen(QColor(0xE0, 0xE0, 0xE0), 0.5));
+    p->setBrush(QColor(255, 255, 255));
+    p->drawPath(combined);
+
+    p->restore();
+}
+
+void MessageDelegate::drawStatusBar(QPainter *p, const Layout &L,
+                                    const QModelIndex &index,
+                                    const QStyleOptionViewItem &opt) const {
+    p->save();
+
+    QRect r = L.statusRect;
+
+    QVariant reactionsVar = index.data(MsgReactionsRole);
+    QVariantList reactions = reactionsVar.toList();
+
+    int rx = r.left();
+    if (!reactions.isEmpty()) {
+        for (const QVariant &rv : reactions) {
+            QVariantMap rm = rv.toMap();
+            QString emoji = rm["emoji"].toString();
+            int count = rm["count"].toInt();
+            QVariant colorsVar = rm["colors"];
+            QList<QColor> colors = colorsVar.value<QList<QColor>>();
+
+            if (count < 4 && !colors.isEmpty()) {
+                int iconSize = 16;
+                for (int i = colors.size() - 1; i >= 0; --i) {
+                    int cx = rx + i * 11;
+                    p->setPen(Qt::NoPen);
+                    p->setBrush(colors[i]);
+                    p->drawEllipse(cx, r.top() + 1, iconSize, iconSize);
+                }
+                rx += colors.size() * 11 + 8;
+            } else {
+                QFont emojiFont = opt.font;
+                emojiFont.setPointSize(emojiFont.pointSize() - 1);
+                p->setFont(emojiFont);
+                p->setPen(opt.palette.text().color());
+                QRect emojiRect(rx, r.top(), 20, r.height());
+                p->drawText(emojiRect, Qt::AlignLeft | Qt::AlignVCenter, emoji);
+                rx += 20;
+
+                QFont countFont = opt.font;
+                countFont.setPointSize(countFont.pointSize() - 2);
+                p->setFont(countFont);
+                p->setPen(QColor(0x80, 0x80, 0x80));
+                QRect cntRect(rx, r.top(), 24, r.height());
+                p->drawText(cntRect, Qt::AlignLeft | Qt::AlignVCenter,
+                            QString::number(count));
+                rx = cntRect.right() + 8;
+            }
+        }
+    }
+
+    QFont smallFont = opt.font;
+    smallFont.setPointSize(smallFont.pointSize() - 2);
+    p->setFont(smallFont);
+    p->setPen(QColor(0x80, 0x80, 0x80));
+
+    QString statusText;
+    if (index.data(MsgEditedRole).toBool()) {
+        statusText = QString::fromUtf8("изменено  ");
+    }
+    statusText += index.data(MsgTimeRole).toString();
+    p->drawText(QRect(r.left(), r.top(), r.width(), r.height()),
+                Qt::AlignRight | Qt::AlignVCenter, statusText);
+
+    p->restore();
+}
+
+void MessageDelegate::drawAvatar(QPainter *p, const Layout &L,
+                                 const QModelIndex &index) const {
+    QPixmap av = index.data(MsgAvatarRole).value<QPixmap>();
+    if (av.isNull()) return;
+
+    p->save();
+    p->setRenderHint(QPainter::Antialiasing);
+    QPainterPath clip;
+    clip.addEllipse(L.avatarRect);
+    p->setClipPath(clip);
+    p->drawPixmap(L.avatarRect, av);
+    p->restore();
+}
diff --git a/tools/chatgui/src/messagedelegate.h b/tools/chatgui/src/messagedelegate.h
new file mode 100644
index 00000000..68d33326
--- /dev/null
+++ b/tools/chatgui/src/messagedelegate.h
@@ -0,0 +1,67 @@
+#pragma once
+
+#include <QStyledItemDelegate>
+
+enum MessageDataRole {
+    MsgAuthorRole       = Qt::UserRole + 1,
+    MsgTextRole         = Qt::UserRole + 2,
+    MsgTimeRole         = Qt::UserRole + 3,
+    MsgEditedRole       = Qt::UserRole + 4,
+    MsgAvatarRole       = Qt::UserRole + 5,
+    MsgHasQuoteRole     = Qt::UserRole + 6,
+    MsgQuoteAuthorRole  = Qt::UserRole + 7,
+    MsgQuoteTextRole    = Qt::UserRole + 8,
+    MsgReactionsRole    = Qt::UserRole + 9,
+};
+
+class MessageDelegate : public QStyledItemDelegate {
+    Q_OBJECT
+public:
+    explicit MessageDelegate(QObject *parent = nullptr);
+
+    void paint(QPainter *painter, const QStyleOptionViewItem &option,
+               const QModelIndex &index) const override;
+    QSize sizeHint(const QStyleOptionViewItem &option,
+                   const QModelIndex &index) const override;
+
+private:
+    struct Layout {
+        int viewWidth;
+        int bubbleWidth;
+        QRect avatarRect;
+        QRect bubbleRect;
+        QRect quoteRect;
+        QRect quoteBarRect;
+        QRect quoteAuthorRect;
+        QRect quoteTextRect;
+        QRect textRect;
+        QRect statusRect;
+        int totalHeight;
+    };
+
+    Layout calcLayout(const QStyleOptionViewItem &option,
+                      const QModelIndex &index) const;
+    void drawQuote(QPainter *p, const Layout &L,
+                   const QModelIndex &index, const QStyleOptionViewItem &opt) const;
+    void drawBubble(QPainter *p, const Layout &L) const;
+    void drawStatusBar(QPainter *p, const Layout &L,
+                       const QModelIndex &index, const QStyleOptionViewItem &opt) const;
+    void drawAvatar(QPainter *p, const Layout &L,
+                    const QModelIndex &index) const;
+
+    static constexpr int kAvatar   = 36;
+    static constexpr int kGap      = 8;
+    static constexpr int kRadius   = 10;
+    static constexpr int kPadH     = 12;
+    static constexpr int kPadTop   = 8;
+    static constexpr int kPadBot   = 6;
+    static constexpr int kTail     = 6;
+    static constexpr int kMarginH  = 8;
+    static constexpr int kItemGap  = 3;
+    static constexpr int kQuoteGap = 4;
+    static constexpr int kQuotePadH = 6;
+    static constexpr int kQuotePadV = 6;
+    static constexpr int kQuoteBarW = 2;
+    static constexpr int kQuoteAv  = 16;
+    static constexpr int kStatusH  = 18;
+};
diff --git a/tools/chatgui/src/messagelist.cpp b/tools/chatgui/src/messagelist.cpp
new file mode 100644
index 00000000..5c18dc8e
--- /dev/null
+++ b/tools/chatgui/src/messagelist.cpp
@@ -0,0 +1,179 @@
+#include "messagelist.h"
+#include "chatview.h"
+#include "messagedelegate.h"
+#include <QVBoxLayout>
+#include <QPainter>
+#include <QPixmap>
+
+static QPixmap makeAvatar(const QColor &color, const QString &letter, int size = 36) {
+    QPixmap pix(size, size);
+    pix.fill(Qt::transparent);
+    QPainter p(&pix);
+    p.setRenderHint(QPainter::Antialiasing);
+    p.setBrush(color);
+    p.setPen(Qt::NoPen);
+    p.drawEllipse(0, 0, size, size);
+    p.setPen(Qt::white);
+    QFont f = p.font();
+    f.setBold(true);
+    f.setPointSize(size / 3);
+    p.setFont(f);
+    p.drawText(QRect(0, 0, size, size), Qt::AlignCenter, letter);
+    p.end();
+    return pix;
+}
+
+static QVariant makeReaction(const QString &emoji, int count,
+                             const QList<QColor> &colors = {}) {
+    QVariantMap m;
+    m["emoji"] = emoji;
+    m["count"] = count;
+    if (!colors.isEmpty())
+        m["colors"] = QVariant::fromValue(colors);
+    return m;
+}
+
+MessageList::MessageList(QWidget *parent)
+    : QWidget(parent)
+    , m_view(new ChatView(this))
+    , m_model(new QStandardItemModel(this))
+{
+    auto *layout = new QVBoxLayout(this);
+    layout->setContentsMargins(0, 0, 0, 0);
+    layout->setSpacing(0);
+
+    m_view->setModel(m_model);
+    m_view->setItemDelegate(new MessageDelegate(this));
+    m_view->setEditTriggers(QAbstractItemView::NoEditTriggers);
+    m_view->setSelectionMode(QAbstractItemView::NoSelection);
+    m_view->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+    m_view->setVerticalScrollMode(QAbstractItemView::ScrollPerPixel);
+    m_view->setFrameShape(QFrame::NoFrame);
+    m_view->setBackgroundImage("../resources/bg.jpg");
+    layout->addWidget(m_view);
+
+    populateStubData();
+}
+
+static void setMsg(QStandardItem *item,
+                   const QString &author, const QString &text, const QString &time,
+                   const QPixmap &avatar, bool edited,
+                   bool hasQuote, const QString &qAuthor, const QString &qText,
+                   const QVariantList &reactions) {
+    item->setData(author,  MsgAuthorRole);
+    item->setData(text,    MsgTextRole);
+    item->setData(time,    MsgTimeRole);
+    item->setData(edited,  MsgEditedRole);
+    item->setData(QVariant::fromValue(avatar), MsgAvatarRole);
+    item->setData(hasQuote, MsgHasQuoteRole);
+    if (hasQuote) {
+        item->setData(qAuthor, MsgQuoteAuthorRole);
+        item->setData(qText,   MsgQuoteTextRole);
+    }
+    if (!reactions.isEmpty())
+        item->setData(reactions, MsgReactionsRole);
+}
+
+void MessageList::populateStubData() {
+    QColor cAlice(74, 144, 226), cBob(126, 211, 33), cCarol(245, 166, 35);
+    QColor cDave(144, 19, 254), cEve(0, 184, 148);
+    auto avAlice = makeAvatar(cAlice, "A");
+    auto avBob   = makeAvatar(cBob,   "B");
+    auto avCarol = makeAvatar(cCarol, "C");
+    auto avDave  = makeAvatar(cDave,  "D");
+
+    auto *m0 = new QStandardItem();
+    setMsg(m0,
+        QString::fromUtf8("Alice"),
+        QString::fromUtf8("Hey team! How's the deployment going?"),
+        "10:15", avAlice, false,
+        false, QString(), QString(),
+        {});
+    m_model->appendRow(m0);
+
+    auto *m1 = new QStandardItem();
+    setMsg(m1,
+        QString::fromUtf8("Bob"),
+        QString::fromUtf8("All green on staging. Running the final integration tests now."),
+        "10:17", avBob, false,
+        false, QString(), QString(),
+        QVariantList{makeReaction(QString::fromUtf8("\xF0\x9F\x91\x8D"), 2,
+                                  {cAlice, cCarol})});
+    m_model->appendRow(m1);
+
+    auto *m2 = new QStandardItem();
+    setMsg(m2,
+        QString::fromUtf8("Carol"),
+        QString::fromUtf8("I've pushed the ETCP-42 fix to staging. BGP handshake should be stable now. Please review the patch when you get a chance."),
+        "10:22", avCarol, true,
+        false, QString(), QString(),
+        QVariantList{
+            makeReaction(QString::fromUtf8("\xF0\x9F\x91\x8D"), 3,
+                         {cAlice, cBob, cDave}),
+            makeReaction(QString::fromUtf8("\xE2\x9D\xA4\xEF\xB8\x8F"), 1,
+                         {cAlice})
+        });
+    m_model->appendRow(m2);
+
+    auto *m3 = new QStandardItem();
+    setMsg(m3,
+        QString::fromUtf8("Dave"),
+        QString::fromUtf8("Wait — the BGP session is still flapping after the handshake. I'm seeing the keepalive timer fire but no route updates come through. Logs attached."),
+        "10:25", avDave, false,
+        true,
+        QString::fromUtf8("Carol"),
+        QString::fromUtf8("BGP handshake should be stable now"),
+        QVariantList{
+            makeReaction(QString::fromUtf8("\xF0\x9F\x98\xAE"), 1,
+                         {cBob})
+        });
+    m_model->appendRow(m3);
+
+    auto *m4 = new QStandardItem();
+    setMsg(m4,
+        QString::fromUtf8("Alice"),
+        QString::fromUtf8("Reviewed the patch. LGTM. Let's merge and deploy to production tomorrow morning."),
+        "10:28", avAlice, false,
+        false, QString(), QString(),
+        QVariantList{
+            makeReaction(QString::fromUtf8("\xF0\x9F\x91\x8D"), 5),
+            makeReaction(QString::fromUtf8("\xF0\x9F\x8E\x89"), 2,
+                         {cBob, cEve})
+        });
+    m_model->appendRow(m4);
+
+    auto *m5 = new QStandardItem();
+    setMsg(m5,
+        QString::fromUtf8("Bob"),
+        QString::fromUtf8("Can you share the full logs for the BGP session? I'll dig into the keepalive timer logic."),
+        "10:30", avBob, false,
+        true,
+        QString::fromUtf8("Dave"),
+        QString::fromUtf8("keepalive timer fire but no route updates"),
+        {});
+    m_model->appendRow(m5);
+
+    auto *m6 = new QStandardItem();
+    setMsg(m6,
+        QString::fromUtf8("Carol"),
+        QString::fromUtf8("Sounds good. Let's coordinate in #dev-team. I'll prepare the release notes."),
+        "10:33", avCarol, false,
+        false, QString(), QString(),
+        {});
+    m_model->appendRow(m6);
+
+    auto *m7 = new QStandardItem();
+    setMsg(m7,
+        QString::fromUtf8("Alice"),
+        QString::fromUtf8("Deploy scheduled for tomorrow 10:00 UTC. All features are frozen — no more merges to main."),
+        "10:35", avAlice, false,
+        false, QString(), QString(),
+        QVariantList{
+            makeReaction(QString::fromUtf8("\xF0\x9F\x9A\x80"), 3,
+                         {cBob, cCarol, cDave}),
+            makeReaction(QString::fromUtf8("\xE2\x9D\xA4\xEF\xB8\x8F"), 7)
+        });
+    m_model->appendRow(m7);
+
+    m_view->scrollToBottom();
+}
diff --git a/tools/chatgui/src/messagelist.h b/tools/chatgui/src/messagelist.h
new file mode 100644
index 00000000..cd37eae3
--- /dev/null
+++ b/tools/chatgui/src/messagelist.h
@@ -0,0 +1,17 @@
+#pragma once
+
+#include <QWidget>
+#include <QStandardItemModel>
+
+class ChatView;
+
+class MessageList : public QWidget {
+    Q_OBJECT
+public:
+    explicit MessageList(QWidget *parent = nullptr);
+
+private:
+    ChatView *m_view;
+    QStandardItemModel *m_model;
+    void populateStubData();
+};