diff --git a/src/index.html b/src/index.html
index 7912757..7f8ca89 100644
--- a/src/index.html
+++ b/src/index.html
@@ -1536,6 +1536,18 @@
             </div>
         </div>
 
+        <!-- Bottom Panel (REPL Output) -->
+        <div class="bottom-panel collapsed" id="bottom-panel">
+            <div class="bottom-panel-header">
+                <span class="bottom-panel-title">Output</span>
+                <div class="bottom-panel-actions">
+                    <button class="bottom-panel-btn" id="repl-clear" title="Clear output">Clear</button>
+                    <button class="bottom-panel-btn" id="bottom-panel-toggle" title="Toggle panel">&#x25BC;</button>
+                </div>
+            </div>
+            <div class="bottom-panel-content" id="repl-output"></div>
+        </div>
+
         <div class="status-bar" id="status-bar">
             <div class="status-bar-left">
                 <span class="status-item" id="status-text">Ready</span>
diff --git a/src/main.js b/src/main.js
index 42cf052..b6e9efb 100644
--- a/src/main.js
+++ b/src/main.js
@@ -3925,4 +3925,164 @@ ipcMain.on('insert-generated-content', (event, content) => {
   if (mainWindow && !mainWindow.isDestroyed()) {
     mainWindow.webContents.send('insert-content', content);
   }
+});
+
+// ============================================
+// File Explorer IPC Handlers
+// ============================================
+ipcMain.handle('list-directory', async (event, dirPath) => {
+  try {
+    if (!dirPath) {
+      const result = await dialog.showOpenDialog(mainWindow, {
+        properties: ['openDirectory']
+      });
+      if (result.canceled || !result.filePaths[0]) return null;
+      dirPath = result.filePaths[0];
+    }
+    const entries = fs.readdirSync(dirPath, { withFileTypes: true })
+      .filter(e => !e.name.startsWith('.'))
+      .sort((a, b) => {
+        if (a.isDirectory() && !b.isDirectory()) return -1;
+        if (!a.isDirectory() && b.isDirectory()) return 1;
+        return a.name.localeCompare(b.name);
+      })
+      .map(e => ({
+        name: e.name,
+        isDirectory: e.isDirectory(),
+        path: path.join(dirPath, e.name)
+      }));
+    return { path: dirPath, entries };
+  } catch (err) {
+    console.error('list-directory error:', err);
+    return null;
+  }
+});
+
+// Open a file by path (from explorer panel)
+ipcMain.on('open-file-path', (event, filePath) => {
+  try {
+    if (!fs.existsSync(filePath)) return;
+    const stat = fs.statSync(filePath);
+    if (stat.size > MAX_FILE_SIZE) return;
+    currentFile = filePath;
+    const content = fs.readFileSync(filePath, 'utf-8');
+    mainWindow.webContents.send('file-opened', { path: filePath, content });
+  } catch (err) {
+    console.error('open-file-path error:', err);
+  }
+});
+
+// ============================================
+// Git IPC Handlers
+// ============================================
+const simpleGit = require('simple-git');
+
+function getGitRepo() {
+  // Use the directory of the current file, or the app's working directory
+  const dir = currentFile ? path.dirname(currentFile) : process.cwd();
+  return simpleGit(dir);
+}
+
+ipcMain.handle('git-status', async () => {
+  try {
+    const git = getGitRepo();
+    return await git.status();
+  } catch (err) {
+    return { error: 'Not a git repository' };
+  }
+});
+
+ipcMain.handle('git-stage', async (event, { files }) => {
+  try {
+    const git = getGitRepo();
+    await git.add(files);
+    return await git.status();
+  } catch (err) {
+    return { error: err.message };
+  }
+});
+
+ipcMain.handle('git-commit', async (event, { message }) => {
+  try {
+    const git = getGitRepo();
+    return await git.commit(message);
+  } catch (err) {
+    return { error: err.message };
+  }
+});
+
+ipcMain.handle('git-log', async () => {
+  try {
+    const git = getGitRepo();
+    return await git.log({ maxCount: 20 });
+  } catch (err) {
+    return { error: err.message };
+  }
+});
+
+// ============================================
+// Snippets IPC Handlers
+// ============================================
+const snippetsPath = path.join(app.getPath('userData'), 'snippets.json');
+
+function loadSnippets() {
+  try {
+    if (fs.existsSync(snippetsPath)) {
+      return JSON.parse(fs.readFileSync(snippetsPath, 'utf-8'));
+    }
+  } catch (err) { console.error('Failed to load snippets:', err); }
+  return [];
+}
+
+function saveSnippetsFile(snippets) {
+  fs.writeFileSync(snippetsPath, JSON.stringify(snippets, null, 2));
+}
+
+ipcMain.handle('get-snippets', async () => loadSnippets());
+
+ipcMain.handle('save-snippet', async (event, snippet) => {
+  const snippets = loadSnippets();
+  const existing = snippets.findIndex(s => s.id === snippet.id);
+  if (existing >= 0) snippets[existing] = snippet;
+  else snippets.push(snippet);
+  saveSnippetsFile(snippets);
+  return snippets;
+});
+
+ipcMain.handle('delete-snippet', async (event, id) => {
+  const snippets = loadSnippets().filter(s => s.id !== id);
+  saveSnippetsFile(snippets);
+  return snippets;
+});
+
+// ============================================
+// Code Execution (REPL) IPC Handler
+// ============================================
+ipcMain.handle('execute-code', async (event, { code, language }) => {
+  const timeout = 10000;
+
+  return new Promise((resolve) => {
+    let cmd, args;
+    if (language === 'javascript' || language === 'js') {
+      cmd = 'node';
+      args = ['-e', code];
+    } else if (language === 'python' || language === 'py') {
+      cmd = process.platform === 'win32' ? 'python' : 'python3';
+      args = ['-c', code];
+    } else if (language === 'bash' || language === 'sh') {
+      cmd = process.platform === 'win32' ? 'cmd' : 'bash';
+      args = process.platform === 'win32' ? ['/c', code] : ['-c', code];
+    } else {
+      resolve({ error: `Unsupported language: ${language}` });
+      return;
+    }
+
+    execFile(cmd, args, { timeout, maxBuffer: 1024 * 1024 }, (err, stdout, stderr) => {
+      resolve({
+        stdout: stdout || '',
+        stderr: stderr || '',
+        error: err?.killed ? 'Execution timed out (10s limit)' : (err?.message || null)
+      });
+    });
+  });
 });
\ No newline at end of file
diff --git a/src/preload.js b/src/preload.js
index c076d34..334006e 100644
--- a/src/preload.js
+++ b/src/preload.js
@@ -97,7 +97,27 @@ const ALLOWED_SEND_CHANNELS = [
   'save-pasted-image',
 
   // Templates
-  'load-template'
+  'load-template',
+
+  // File Explorer
+  'list-directory',
+
+  // Git
+  'git-status',
+  'git-stage',
+  'git-commit',
+  'git-log',
+
+  // Snippets
+  'get-snippets',
+  'save-snippet',
+  'delete-snippet',
+
+  // Code execution (REPL)
+  'execute-code',
+
+  // File open by path
+  'open-file-path'
 ];
 
 const ALLOWED_RECEIVE_CHANNELS = [
diff --git a/src/renderer.js b/src/renderer.js
index e638e39..e8e1167 100644
--- a/src/renderer.js
+++ b/src/renderer.js
@@ -12,6 +12,10 @@ const { createEditor } = require('./editor/codemirror-setup');
 const { undo, redo } = require('@codemirror/commands');
 const { SidebarManager } = require('./sidebar/sidebar-manager');
 const { renderTemplatesPanel } = require('./sidebar/templates-panel');
+const { renderExplorerPanel } = require('./sidebar/explorer-panel');
+const { renderGitPanel } = require('./sidebar/git-panel');
+const { renderSnippetsPanel } = require('./sidebar/snippets-panel');
+const { ReplPanel } = require('./repl/repl-panel');
 const { CommandPalette } = require('./command-palette');
 const { PrintPreview } = require('./print-preview');
 
@@ -488,6 +492,26 @@ class TabManager {
 
                 pre.parentElement.replaceChild(img, pre);
             });
+
+            // Add Run buttons to executable code blocks (REPL)
+            const codeBlocks = preview.querySelectorAll('pre code[class*="language-"]');
+            codeBlocks.forEach(block => {
+                const lang = block.className.match(/language-(\w+)/)?.[1];
+                if (['javascript', 'js', 'python', 'py', 'bash', 'sh'].includes(lang)) {
+                    const runBtn = document.createElement('button');
+                    runBtn.className = 'code-run-btn';
+                    runBtn.textContent = '\u25B6 Run';
+                    runBtn.addEventListener('click', async () => {
+                        if (replPanel) {
+                            replPanel.show();
+                            const result = await ipcRenderer.invoke('execute-code', { code: block.textContent, language: lang });
+                            replPanel.appendOutput(`[${lang}]`, result);
+                        }
+                    });
+                    block.parentElement.style.position = 'relative';
+                    block.parentElement.appendChild(runBtn);
+                }
+            });
         } catch (error) {
             console.error('Error rendering preview:', error);
             preview.innerHTML = '<p class="error">Error rendering preview. Please check your markdown syntax.</p>';
@@ -1118,23 +1142,42 @@ class TabManager {
 
 // Initialize tab manager
 let tabManager;
+let replPanel;
 
 document.addEventListener('DOMContentLoaded', () => {
     tabManager = new TabManager();
+    replPanel = new ReplPanel();
 
     // Initialize sidebar
     const sidebarManager = new SidebarManager();
+    let explorerCurrentDir = null;
+
     sidebarManager.registerPanel('explorer', {
         title: 'Explorer',
-        render: (container) => { container.innerHTML = '<p style="color:#888;padding:8px;">File explorer coming soon...</p>'; }
+        render: (container) => renderExplorerPanel(container, {
+            listDirectory: (dir) => ipcRenderer.invoke('list-directory', dir),
+            onFileOpen: (filePath) => ipcRenderer.send('open-file-path', filePath),
+            currentDir: explorerCurrentDir,
+        })
     });
     sidebarManager.registerPanel('git', {
         title: 'Git',
-        render: (container) => { container.innerHTML = '<p style="color:#888;padding:8px;">Git panel coming soon...</p>'; }
+        render: (container) => renderGitPanel(container, {
+            gitStatus: () => ipcRenderer.invoke('git-status'),
+            gitDiff: (file) => ipcRenderer.invoke('git-diff', { file }),
+            gitStage: (files) => ipcRenderer.invoke('git-stage', { files }),
+            gitCommit: (message) => ipcRenderer.invoke('git-commit', { message }),
+            gitLog: () => ipcRenderer.invoke('git-log'),
+        })
     });
     sidebarManager.registerPanel('snippets', {
         title: 'Snippets',
-        render: (container) => { container.innerHTML = '<p style="color:#888;padding:8px;">Snippets coming soon...</p>'; }
+        render: (container) => renderSnippetsPanel(container, {
+            getSnippets: () => ipcRenderer.invoke('get-snippets'),
+            saveSnippet: (s) => ipcRenderer.invoke('save-snippet', s),
+            deleteSnippet: (id) => ipcRenderer.invoke('delete-snippet', id),
+            onInsert: (code) => tabManager.insertAtCursor(code),
+        })
     });
     sidebarManager.registerPanel('templates', {
         title: 'Templates',
diff --git a/src/styles-sidebar.css b/src/styles-sidebar.css
index e735570..c32aad6 100644
--- a/src/styles-sidebar.css
+++ b/src/styles-sidebar.css
@@ -161,3 +161,108 @@ body[class*="dark"] .panel-list-item-title {
 body[class*="dark"] .panel-list-item-desc {
     color: #888;
 }
+
+/* Explorer Panel */
+.explorer-toolbar {
+    display: flex;
+    gap: 4px;
+    margin-bottom: 8px;
+}
+.explorer-path {
+    flex: 1;
+    padding: 6px 8px;
+    border: 1px solid var(--gray-300, #d1d5db);
+    border-radius: 6px;
+    font-size: 12px;
+    background: white;
+    overflow: hidden;
+    text-overflow: ellipsis;
+}
+.explorer-browse-btn {
+    border: 1px solid var(--gray-300, #d1d5db);
+    border-radius: 6px;
+    background: white;
+    cursor: pointer;
+    padding: 4px 8px;
+}
+.tree-item {
+    padding: 3px 0;
+    cursor: pointer;
+    font-size: 13px;
+    user-select: none;
+}
+.tree-item:hover {
+    background: var(--gray-100, #f3f4f6);
+    border-radius: 4px;
+}
+.tree-icon {
+    margin-right: 4px;
+    font-size: 12px;
+}
+.tree-children {
+    padding-left: 16px;
+}
+.tree-folder.collapsed .tree-children {
+    display: none;
+}
+.tree-name {
+    font-size: 13px;
+}
+
+/* Git Panel */
+.git-section { margin-bottom: 16px; }
+.git-section-title { font-size: 11px; text-transform: uppercase; letter-spacing: 0.05em; color: var(--gray-500); margin-bottom: 8px; }
+.git-file { display: flex; align-items: center; padding: 4px 6px; border-radius: 4px; font-size: 13px; gap: 6px; }
+.git-file:hover { background: var(--gray-100, #f3f4f6); }
+.git-file-status { font-weight: 700; font-family: monospace; width: 16px; text-align: center; }
+.git-file-name { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
+.git-stage-btn { border: none; background: var(--gray-200); border-radius: 4px; cursor: pointer; font-size: 14px; width: 22px; height: 22px; }
+.git-commit-input { width: 100%; padding: 8px; border: 1px solid var(--gray-300); border-radius: 6px; font-size: 13px; font-family: inherit; resize: vertical; box-sizing: border-box; }
+.git-commit-btn { width: 100%; margin-top: 8px; padding: 8px; background: var(--primary-dark, #5661b3); color: white; border: none; border-radius: 6px; font-size: 13px; cursor: pointer; }
+.git-commit-btn:hover { opacity: 0.9; }
+.git-log-entry { padding: 6px 0; border-bottom: 1px solid var(--gray-100); }
+.git-log-msg { font-size: 13px; }
+.git-log-meta { font-size: 11px; color: var(--gray-500); margin-top: 2px; }
+.git-info { font-size: 13px; color: var(--gray-500); padding: 8px 0; }
+.git-loading { font-size: 13px; color: var(--gray-400); }
+
+/* Snippets Panel */
+.snippets-toolbar { display: flex; gap: 4px; margin-bottom: 8px; }
+.snippets-search { flex: 1; padding: 6px 10px; border: 1px solid var(--gray-300); border-radius: 6px; font-size: 13px; }
+.snippets-add-btn { width: 32px; border: 1px solid var(--gray-300); border-radius: 6px; background: white; font-size: 18px; cursor: pointer; }
+.snippet-item { padding: 8px; border: 1px solid var(--gray-200); border-radius: 6px; margin-bottom: 6px; }
+.snippet-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 4px; }
+.snippet-name { font-size: 13px; font-weight: 500; }
+.snippet-lang { font-size: 11px; background: var(--gray-100); padding: 2px 6px; border-radius: 4px; color: var(--gray-500); }
+.snippet-preview { font-size: 12px; background: var(--gray-50); padding: 6px; border-radius: 4px; margin: 4px 0; overflow: hidden; max-height: 60px; }
+.snippet-preview code { font-family: 'JetBrains Mono', monospace; }
+.snippet-actions { display: flex; gap: 4px; }
+.snippet-insert { font-size: 12px; padding: 4px 8px; border: 1px solid var(--gray-300); border-radius: 4px; background: white; cursor: pointer; }
+.snippet-delete { font-size: 14px; padding: 4px 8px; border: 1px solid var(--gray-300); border-radius: 4px; background: white; cursor: pointer; color: #ef4444; }
+
+/* Dark theme for sidebar panels */
+body[class*="dark"] .explorer-path,
+body[class*="dark"] .explorer-browse-btn,
+body[class*="dark"] .snippets-search,
+body[class*="dark"] .snippets-add-btn,
+body[class*="dark"] .snippet-insert,
+body[class*="dark"] .snippet-delete {
+    background: #2d2d2d;
+    border-color: #444;
+    color: #ccc;
+}
+body[class*="dark"] .git-commit-input {
+    background: #2d2d2d;
+    border-color: #444;
+    color: #ccc;
+}
+body[class*="dark"] .snippet-item {
+    border-color: #444;
+}
+body[class*="dark"] .snippet-preview {
+    background: #2d2d2d;
+}
+body[class*="dark"] .tree-item:hover,
+body[class*="dark"] .git-file:hover {
+    background: #333;
+}
diff --git a/src/styles.css b/src/styles.css
index a901a8a..639f488 100644
--- a/src/styles.css
+++ b/src/styles.css
@@ -290,6 +290,43 @@ body {
     line-height: 1.6;
 }
 
+/* Bottom Panel (REPL Output) */
+.bottom-panel { display: flex; flex-direction: column; border-top: 1px solid var(--gray-200, #e5e7eb); flex-shrink: 0; }
+.bottom-panel.collapsed { height: 0; overflow: hidden; border: none; }
+.bottom-panel:not(.collapsed) { height: 200px; }
+.bottom-panel-header { display: flex; justify-content: space-between; align-items: center; padding: 6px 12px; background: var(--gray-50, #f9fafb); border-bottom: 1px solid var(--gray-200); }
+.bottom-panel-title { font-size: 13px; font-weight: 600; color: var(--gray-600); }
+.bottom-panel-actions { display: flex; gap: 4px; }
+.bottom-panel-btn { font-size: 12px; padding: 4px 8px; border: 1px solid var(--gray-300); border-radius: 4px; background: white; cursor: pointer; }
+.bottom-panel-content { flex: 1; overflow-y: auto; padding: 12px; font-family: 'JetBrains Mono', monospace; font-size: 13px; background: #1e1e1e; color: #d4d4d4; }
+.repl-entry { margin-bottom: 8px; }
+.repl-command { color: #569cd6; margin-bottom: 2px; }
+.repl-stdout { color: #d4d4d4; white-space: pre-wrap; }
+.repl-stderr { color: #f44747; white-space: pre-wrap; }
+.repl-error { color: #f44747; }
+
+/* Code Run Button */
+.code-run-btn {
+    position: absolute;
+    top: 6px;
+    right: 6px;
+    padding: 4px 10px;
+    font-size: 12px;
+    background: var(--primary-dark, #5661b3);
+    color: white;
+    border: none;
+    border-radius: 4px;
+    cursor: pointer;
+    opacity: 0;
+    transition: opacity 0.2s;
+}
+pre:hover .code-run-btn { opacity: 1; }
+
+/* Dark theme bottom panel */
+body[class*="dark"] .bottom-panel-header { background: #1e1e1e; border-color: #333; }
+body[class*="dark"] .bottom-panel-btn { background: #2d2d2d; border-color: #444; color: #ccc; }
+body[class*="dark"] .bottom-panel-title { color: #ccc; }
+
 /* Status Bar */
 .status-bar {
     display: flex;