Allow binding to a specific IP address via exposeToNetwork setting

Author: erusev

LlamaBarn/Menu/HeaderView.swift

@@ -78,8 +78,17 @@ final class HeaderView: ItemView {
     // Connect to server info
     appNameLabel.stringValue = "LlamaBarn"
 
-    let host =
-      UserSettings.exposeToNetwork ? (LlamaServer.getLocalIpAddress() ?? "0.0.0.0") : "localhost"
+    // Determine host: use bind address if set, otherwise localhost
+    // For 0.0.0.0, show the actual local IP for user convenience
+    let host: String
+    if let bindAddress = UserSettings.networkBindAddress {
+      host =
+        bindAddress == "0.0.0.0"
+        ? (LlamaServer.getLocalIpAddress() ?? "0.0.0.0")
+        : bindAddress
+    } else {
+      host = "localhost"
+    }
     let linkText = "\(host):\(LlamaServer.defaultPort)"
     let apiUrlString = "http://\(linkText)/v1"
     let webUiUrlString = "http://\(linkText)/"

LlamaBarn/Menu/MenuController.swift

@@ -245,8 +245,16 @@ final class MenuController: NSObject, NSMenuDelegate {
     guard !models.isEmpty else { return }
 
     // Build the /models endpoint URL
-    let host =
-      UserSettings.exposeToNetwork ? (LlamaServer.getLocalIpAddress() ?? "0.0.0.0") : "localhost"
+    // For 0.0.0.0, show the actual local IP for user convenience
+    let host: String
+    if let bindAddress = UserSettings.networkBindAddress {
+      host =
+        bindAddress == "0.0.0.0"
+        ? (LlamaServer.getLocalIpAddress() ?? "0.0.0.0")
+        : bindAddress
+    } else {
+      host = "localhost"
+    }
     let modelsUrl = URL(string: "http://\(host):\(LlamaServer.defaultPort)/models")
 
     // Create family item (not collapsible) with link to /models endpoint

LlamaBarn/Settings/UserSettings.swift

@@ -53,18 +53,24 @@ enum UserSettings {
     }
   }
 
-  /// Whether to expose llama-server to the network (bind to 0.0.0.0).
-  /// Defaults to `false` (localhost only). When `true`, allows connections from other devices
-  /// on the same network.
-  static var exposeToNetwork: Bool {
-    get {
-      defaults.bool(forKey: Keys.exposeToNetwork)
+  /// The network bind address for llama-server, or `nil` for localhost only.
+  /// Accepts either a bool (`true` binds to `0.0.0.0`) or a specific IP address string.
+  /// Examples:
+  ///   `defaults write app.llamabarn.LlamaBarn exposeToNetwork -bool true` → binds to 0.0.0.0
+  ///   `defaults write app.llamabarn.LlamaBarn exposeToNetwork -string "192.168.1.100"` → binds to that IP
+  ///   `defaults delete app.llamabarn.LlamaBarn exposeToNetwork` → localhost only
+  static var networkBindAddress: String? {
+    let obj = defaults.object(forKey: Keys.exposeToNetwork)
+    // If it's a string, use it directly as the bind address
+    if let str = obj as? String {
+      return str
     }
-    set {
-      guard defaults.bool(forKey: Keys.exposeToNetwork) != newValue else { return }
-      defaults.set(newValue, forKey: Keys.exposeToNetwork)
-      NotificationCenter.default.post(name: .LBUserSettingsDidChange, object: nil)
+    // If it's a bool and true, bind to all interfaces
+    if let bool = obj as? Bool, bool {
+      return "0.0.0.0"
     }
+    // Not set or false → localhost only
+    return nil
   }
 
   /// The default context length in thousands of tokens.

LlamaBarn/System/LlamaServer.swift

@@ -151,9 +151,9 @@ class LlamaServer {
       "--fit-target", String(Int(CatalogEntry.memOverheadMb)),
     ]
 
-    // Bind to 0.0.0.0 if exposeToNetwork is enabled
-    if UserSettings.exposeToNetwork {
-      arguments.append(contentsOf: ["--host", "0.0.0.0"])
+    // Bind to custom address if network exposure is enabled
+    if let bindAddress = UserSettings.networkBindAddress {
+      arguments.append(contentsOf: ["--host", bindAddress])
     }
 
     // Unload model from memory when idle

readme.md

@@ -60,7 +60,14 @@ See complete API reference in `llama-server` [docs](https://github.com/ggml-org/
 **Expose to network** — By default, the server is only accessible from your Mac (`localhost`). This option allows connections from other devices on your local network. Only enable this if you understand the security risks.
 
 ```sh
+# bind to all interfaces (0.0.0.0)
 defaults write app.llamabarn.LlamaBarn exposeToNetwork -bool YES
+
+# or bind to a specific IP (e.g., for Tailscale)
+defaults write app.llamabarn.LlamaBarn exposeToNetwork -string "100.x.x.x"
+
+# disable (default)
+defaults delete app.llamabarn.LlamaBarn exposeToNetwork
 ```
 
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