diff --git a/public/upload.js b/public/upload.js
new file mode 100644
index 0000000..d500d19
--- /dev/null
+++ b/public/upload.js
@@ -0,0 +1,145 @@
+(function() {
+  const M = window.MusicRoom;
+  
+  document.addEventListener("DOMContentLoaded", () => {
+    const uploadBtn = M.$("#btn-upload");
+    const fileInput = M.$("#file-input");
+    const dropzone = M.$("#upload-dropzone");
+    const libraryPanel = M.$("#library-panel");
+    const progressEl = M.$("#upload-progress");
+    const progressBar = progressEl?.querySelector(".upload-progress-bar");
+    const progressText = progressEl?.querySelector(".upload-progress-text");
+    
+    if (!uploadBtn || !fileInput || !dropzone) return;
+    
+    // Click upload button opens file dialog
+    uploadBtn.onclick = () => {
+      if (!M.currentUser) {
+        M.showToast("Sign in to upload");
+        return;
+      }
+      fileInput.click();
+    };
+    
+    // File input change
+    fileInput.onchange = () => {
+      if (fileInput.files.length > 0) {
+        uploadFiles(fileInput.files);
+        fileInput.value = "";
+      }
+    };
+    
+    // Drag and drop on library panel
+    let dragCounter = 0;
+    
+    libraryPanel.ondragenter = (e) => {
+      if (!M.currentUser) return;
+      if (!e.dataTransfer.types.includes("Files")) return;
+      e.preventDefault();
+      dragCounter++;
+      dropzone.classList.remove("hidden");
+    };
+    
+    libraryPanel.ondragleave = (e) => {
+      e.preventDefault();
+      dragCounter--;
+      if (dragCounter === 0) {
+        dropzone.classList.add("hidden");
+      }
+    };
+    
+    libraryPanel.ondragover = (e) => {
+      if (!M.currentUser) return;
+      if (!e.dataTransfer.types.includes("Files")) return;
+      e.preventDefault();
+      e.dataTransfer.dropEffect = "copy";
+    };
+    
+    libraryPanel.ondrop = (e) => {
+      e.preventDefault();
+      dragCounter = 0;
+      dropzone.classList.add("hidden");
+      
+      if (!M.currentUser) {
+        M.showToast("Sign in to upload");
+        return;
+      }
+      
+      const files = e.dataTransfer.files;
+      if (files.length > 0) {
+        uploadFiles(files);
+      }
+    };
+    
+    function showProgress(current, total, filename) {
+      if (!progressEl) return;
+      const pct = Math.round((current / total) * 100);
+      progressBar.style.width = pct + "%";
+      progressText.textContent = `Uploading ${current}/${total}: ${filename}`;
+      progressEl.classList.remove("hidden");
+      uploadBtn.classList.add("hidden");
+    }
+    
+    function hideProgress() {
+      if (!progressEl) return;
+      progressEl.classList.add("hidden");
+      uploadBtn.classList.remove("hidden");
+    }
+    
+    async function uploadFiles(files) {
+      const validExts = [".mp3", ".ogg", ".flac", ".wav", ".m4a", ".aac", ".opus", ".wma", ".mp4"];
+      const audioFiles = [...files].filter(f => {
+        const ext = f.name.toLowerCase().match(/\.[^.]+$/)?.[0];
+        return ext && validExts.includes(ext);
+      });
+      
+      if (audioFiles.length === 0) {
+        M.showToast("No valid audio files");
+        return;
+      }
+      
+      let uploaded = 0;
+      let failed = 0;
+      let duplicates = 0;
+      const total = audioFiles.length;
+      
+      for (let i = 0; i < audioFiles.length; i++) {
+        const file = audioFiles[i];
+        showProgress(i + 1, total, file.name);
+        
+        try {
+          const formData = new FormData();
+          formData.append("file", file);
+          
+          const res = await fetch("/api/upload", {
+            method: "POST",
+            body: formData
+          });
+          
+          if (res.ok) {
+            uploaded++;
+          } else if (res.status === 409) {
+            // File already exists
+            M.showToast(`Already uploaded: ${file.name}`, "warning");
+            duplicates++;
+          } else {
+            const err = await res.json().catch(() => ({}));
+            console.error(`Upload failed for ${file.name}:`, err.error || res.status);
+            failed++;
+          }
+        } catch (e) {
+          console.error(`Upload error for ${file.name}:`, e);
+          failed++;
+        }
+      }
+      
+      hideProgress();
+      
+      if (uploaded > 0) {
+        M.showToast(`Uploaded ${uploaded} track${uploaded > 1 ? 's' : ''}${failed > 0 ? `, ${failed} failed` : ''}`);
+      } else {
+        M.showToast(`Upload failed`);
+      }
+    }
+  });
+})();
diff --git a/server.ts b/server.ts
index ac5acfd..910b7ac 100644
--- a/server.ts
+++ b/server.ts
@@ -45,7 +45,21 @@ interface Config {
 }
 
 const CONFIG_PATH = join(import.meta.dir, "config.json");
-const config: Config = await file(CONFIG_PATH).json();
+
+const DEFAULT_CONFIG: Config = {
+  port: 3001,
+  musicDir: "./music",
+  allowGuests: true
+};
+
+// Create default config if missing
+const configFile = file(CONFIG_PATH);
+if (!(await configFile.exists())) {
+  console.log("[Config] Creating default config.json...");
+  await Bun.write(CONFIG_PATH, JSON.stringify(DEFAULT_CONFIG, null, 2));
+}
+
+const config: Config = await configFile.json();
 
 const MUSIC_DIR = resolve(import.meta.dir, config.musicDir);
 const PUBLIC_DIR = join(import.meta.dir, "public");