diff --git a/CHANGELOG.md b/CHANGELOG.md
index af97534..539b0e1 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+- API defaults now use LAN IPs for local development (no auth required)
+- Auth interceptor skips authentication when using LAN endpoints
+
 ## [0.3.0] - 2025-12-30
 
 ### Added
diff --git a/lib/core/api/api_interceptors.dart b/lib/core/api/api_interceptors.dart
index 2973596..135d292 100644
--- a/lib/core/api/api_interceptors.dart
+++ b/lib/core/api/api_interceptors.dart
@@ -4,9 +4,12 @@ import 'package:dio/dio.dart';
 import 'package:flutter_riverpod/flutter_riverpod.dart';
 
 import '../auth/auth_provider.dart';
+import '../config/app_config.dart';
 import '../error/app_exception.dart';
 
 /// Adds authentication token to requests.
+///
+/// Skipped entirely when [AppConfig.requiresAuth] is false (LAN development).
 class AuthInterceptor extends Interceptor {
   AuthInterceptor(this._ref);
 
@@ -14,6 +17,12 @@ class AuthInterceptor extends Interceptor {
 
   @override
   void onRequest(RequestOptions options, RequestInterceptorHandler handler) {
+    // Skip auth for LAN development
+    if (!AppConfig.requiresAuth) {
+      handler.next(options);
+      return;
+    }
+
     final authState = _ref.read(authNotifierProvider);
 
     authState.whenData((auth) {
@@ -27,6 +36,12 @@ class AuthInterceptor extends Interceptor {
 
   @override
   void onError(DioException err, ErrorInterceptorHandler handler) {
+    // Skip auth error handling for LAN development
+    if (!AppConfig.requiresAuth) {
+      handler.next(err);
+      return;
+    }
+
     if (err.response?.statusCode == 401) {
       // Token expired - trigger re-authentication
       _ref.read(authNotifierProvider.notifier).signOut();
diff --git a/lib/core/config/app_config.dart b/lib/core/config/app_config.dart
index 76946be..4fefa51 100644
--- a/lib/core/config/app_config.dart
+++ b/lib/core/config/app_config.dart
@@ -1,19 +1,35 @@
 /// Application configuration from compile-time environment variables.
 ///
-/// Set via: flutter build --dart-define=API_URL=https://...
+/// ## Development (LAN - no auth required)
+/// Default values use LAN IPs for local development:
+/// ```bash
+/// flutter run -d chrome
+/// ```
+///
+/// ## Production (public URLs - auth required)
+/// Override with public URLs for production builds:
+/// ```bash
+/// flutter build web \
+///   --dart-define=CORE_API_URL=https://api.schweitz.net \
+///   --dart-define=TATLOCK_API_URL=https://tatlock.schweitz.net
+/// ```
 class AppConfig {
   AppConfig._();
 
   /// Core API base URL
+  /// - LAN default: No auth required
+  /// - Production: https://api.schweitz.net (requires OIDC)
   static const coreApiUrl = String.fromEnvironment(
     'CORE_API_URL',
-    defaultValue: 'https://api.schweitz.net',
+    defaultValue: 'http://192.168.86.149:8083',
   );
 
   /// Tatlock API base URL
+  /// - LAN default: No auth required
+  /// - Production: https://tatlock.schweitz.net (requires OIDC)
   static const tatlockApiUrl = String.fromEnvironment(
     'TATLOCK_API_URL',
-    defaultValue: 'https://tatlock.schweitz.net',
+    defaultValue: 'http://192.168.86.149:8000',
   );
 
   /// Authentik OIDC discovery URL
@@ -37,4 +53,9 @@ class AppConfig {
 
   /// Whether running in debug mode
   static const isDebug = bool.fromEnvironment('DEBUG', defaultValue: false);
+
+  /// Whether auth is required (false for LAN development)
+  static bool get requiresAuth =>
+      coreApiUrl.contains('schweitz.net') ||
+      tatlockApiUrl.contains('schweitz.net');
 }