diff --git a/packages/auth/example/example.dart b/packages/auth/example/example.dart
index 6abdd1b8..85478101 100644
--- a/packages/auth/example/example.dart
+++ b/packages/auth/example/example.dart
@@ -17,6 +17,7 @@ void main() async {
     // If authentication succeeds, return a User object.
     //
     // Otherwise, return `null`.
+    return null;
   });
 
   app.post('/auth/local', auth.authenticate('local'));
diff --git a/packages/auth/lib/src/auth_token.dart b/packages/auth/lib/src/auth_token.dart
index fda46c4f..be24d29f 100644
--- a/packages/auth/lib/src/auth_token.dart
+++ b/packages/auth/lib/src/auth_token.dart
@@ -86,7 +86,7 @@ class AuthToken {
 
     // var headerString = decodeBase64(split[0]);
     var payloadString = decodeBase64(split[1]);
-    var data = split[0] + '.' + split[1];
+    var data = '${split[0]}.${split[1]}';
     var signature = base64Url.encode(hmac.convert(data.codeUnits).bytes);
 
     if (signature != split[2]) {
@@ -102,9 +102,9 @@ class AuthToken {
   String serialize(Hmac hmac) {
     var headerString = base64Url.encode(json.encode(_header).codeUnits);
     var payloadString = base64Url.encode(json.encode(toJson()).codeUnits);
-    var data = headerString + '.' + payloadString;
+    var data = '$headerString.$payloadString';
     var signature = hmac.convert(data.codeUnits).bytes;
-    return data + '.' + base64Url.encode(signature);
+    return '$data.${base64Url.encode(signature)}';
   }
 
   Map<String, dynamic> toJson() {
diff --git a/packages/auth/lib/src/strategies/local.dart b/packages/auth/lib/src/strategies/local.dart
index cca1ffbf..d4d8b68f 100644
--- a/packages/auth/lib/src/strategies/local.dart
+++ b/packages/auth/lib/src/strategies/local.dart
@@ -39,7 +39,7 @@ class LocalAuthStrategy<User> extends AuthStrategy<User> {
   @override
   Future<User?> authenticate(RequestContext req, ResponseContext res,
       [AngelAuthOptions? options]) async {
-    var _options = options ?? AngelAuthOptions();
+    var localOptions = options ?? AngelAuthOptions();
     User? verificationResult;
 
     if (allowBasic) {
@@ -88,9 +88,9 @@ class LocalAuthStrategy<User> extends AuthStrategy<User> {
 
     if (verificationResult == null ||
         (verificationResult is Map && verificationResult.isEmpty)) {
-      if (_options.failureRedirect != null &&
-          _options.failureRedirect!.isNotEmpty) {
-        await res.redirect(_options.failureRedirect, code: 401);
+      if (localOptions.failureRedirect != null &&
+          localOptions.failureRedirect!.isNotEmpty) {
+        await res.redirect(localOptions.failureRedirect, code: 401);
         return null;
       }