diff --git a/.github/workflows/publish.yaml b/.github/workflows/publish.yaml
index fcb7ccb..f416320 100644
--- a/.github/workflows/publish.yaml
+++ b/.github/workflows/publish.yaml
@@ -4,7 +4,7 @@ name: Publish
 
 on:
   pull_request:
-    branches: [ master ]
+    branches: [ main ]
   push:
     tags: [ 'v[0-9]+.[0-9]+.[0-9]+*' ]
 
diff --git a/.github/workflows/test-package.yml b/.github/workflows/test-package.yml
index c588233..0a6d9cb 100644
--- a/.github/workflows/test-package.yml
+++ b/.github/workflows/test-package.yml
@@ -3,9 +3,9 @@ name: Dart CI
 on:
   # Run CI on pushes to the main branch, and on PRs against main.
   push:
-    branches: [ master ]
+    branches: [ main ]
   pull_request:
-    branches: [ master ]
+    branches: [ main ]
   schedule:
     - cron: "0 0 * * 0"
 env:
@@ -44,10 +44,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        # Add macos-latest and/or windows-latest if relevant for this package
         os: [ubuntu-latest]
-        # Add stable if the package should also be tested on stable
-        sdk: ['3.0', dev]
+        sdk: ['3.3', dev]
     steps:
       - uses: actions/checkout@9bb56186c3b09b4f86b1c65136769dd318469633
       - uses: dart-lang/setup-dart@f0ead981b4d9a35b37f30d36160575d60931ec30
diff --git a/CHANGELOG.md b/CHANGELOG.md
index cbf7efc..8e572ec 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 2.5.1-wip
+
+* Require Dart 3.3
+
 ## 2.5.0
 
 * Introduce new typed `ArgResults` `flag(String)`, `option(String)`, and
diff --git a/analysis_options.yaml b/analysis_options.yaml
index 424f0d3..a96c5ee 100644
--- a/analysis_options.yaml
+++ b/analysis_options.yaml
@@ -6,13 +6,9 @@ linter:
   rules:
     - avoid_unused_constructor_parameters
     - cancel_subscriptions
-    - comment_references
     - literal_only_boolean_expressions
     - missing_whitespace_between_adjacent_strings
     - no_adjacent_strings_in_list
     - no_runtimeType_toString
     - package_api_docs
-    - prefer_relative_imports
-    - test_types_in_equals
     - unnecessary_await_in_return
-    - use_super_parameters
diff --git a/lib/src/arg_parser.dart b/lib/src/arg_parser.dart
index ef91b80..c47c003 100644
--- a/lib/src/arg_parser.dart
+++ b/lib/src/arg_parser.dart
@@ -27,7 +27,7 @@ class ArgParser {
 
   /// A list of the [Option]s in [options] intermingled with [String]
   /// separators.
-  final _optionsAndSeparators = [];
+  final _optionsAndSeparators = <Object>[];
 
   /// Whether or not this parser parses options that appear after non-option
   /// arguments.
@@ -142,7 +142,7 @@ class ArgParser {
         null,
         null,
         defaultsTo,
-        callback == null ? null : (value) => callback(value as bool),
+        callback == null ? null : (bool value) => callback(value),
         OptionType.flag,
         negatable: negatable,
         hide: hide,
@@ -264,7 +264,7 @@ class ArgParser {
         allowed,
         allowedHelp,
         defaultsTo?.toList() ?? <String>[],
-        callback == null ? null : (value) => callback(value as List<String>),
+        callback == null ? null : (List<String> value) => callback(value),
         OptionType.multiple,
         splitCommas: splitCommas,
         hide: hide,
@@ -278,7 +278,7 @@ class ArgParser {
       String? valueHelp,
       Iterable<String>? allowed,
       Map<String, String>? allowedHelp,
-      defaultsTo,
+      Object? defaultsTo,
       Function? callback,
       OptionType type,
       {bool negatable = false,
diff --git a/lib/src/usage.dart b/lib/src/usage.dart
index d97cc2d..1ef9627 100644
--- a/lib/src/usage.dart
+++ b/lib/src/usage.dart
@@ -236,7 +236,7 @@ class _Usage {
   String _buildAllowedList(Option option) {
     var isDefault = option.defaultsTo is List
         ? (option.defaultsTo as List).contains
-        : (value) => value == option.defaultsTo;
+        : (String value) => value == option.defaultsTo;
 
     var allowedBuffer = StringBuffer();
     allowedBuffer.write('[');
diff --git a/pubspec.yaml b/pubspec.yaml
index 40967a6..df4a847 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: args
-version: 2.5.0
+version: 2.5.1-wip
 description: >-
   Library for defining parsers for parsing raw command-line arguments into a set
   of options and values using GNU and POSIX style options.
@@ -9,8 +9,8 @@ topics:
   - cli
 
 environment:
-  sdk: ^3.0.0
+  sdk: ^3.3.0
 
 dev_dependencies:
-  dart_flutter_team_lints: ^1.0.0
+  dart_flutter_team_lints: ^2.0.0
   test: ^1.16.0
diff --git a/test/allow_anything_test.dart b/test/allow_anything_test.dart
index 40bb95b..52e22b7 100644
--- a/test/allow_anything_test.dart
+++ b/test/allow_anything_test.dart
@@ -56,7 +56,8 @@ void main() {
     });
 
     test('works as a subcommand in a CommandRunner', () async {
-      var commandRunner = CommandRunner('command', 'Description of command');
+      var commandRunner =
+          CommandRunner<void>('command', 'Description of command');
       var command = AllowAnythingCommand();
       commandRunner.addCommand(command);
 
diff --git a/test/command_test.dart b/test/command_test.dart
index bae9136..555cc8d 100644
--- a/test/command_test.dart
+++ b/test/command_test.dart
@@ -4,6 +4,7 @@
 
 import 'package:args/command_runner.dart';
 import 'package:test/test.dart';
+
 import 'test_utils.dart';
 
 void main() {
@@ -12,7 +13,7 @@ void main() {
     foo = FooCommand();
 
     // Make sure [Command.runner] is set up.
-    CommandRunner('test', 'A test command runner.').addCommand(foo);
+    CommandRunner<void>('test', 'A test command runner.').addCommand(foo);
   });
 
   group('.invocation has a sane default', () {
@@ -92,7 +93,7 @@ Run "test help" to see global options.'''));
       var wrapping = WrappingCommand();
 
       // Make sure [Command.runner] is set up.
-      CommandRunner('longtest', 'A long-lined test command runner.')
+      CommandRunner<void>('longtest', 'A long-lined test command runner.')
           .addCommand(wrapping);
 
       wrapping.addSubcommand(LongCommand());
@@ -118,7 +119,7 @@ options.'''));
       var longCommand = LongCommand();
 
       // Make sure [Command.runner] is set up.
-      CommandRunner('longtest', 'A long-lined test command runner.')
+      CommandRunner<void>('longtest', 'A long-lined test command runner.')
           .addCommand(longCommand);
 
       expect(longCommand.usage, equals('''
diff --git a/test/parse_test.dart b/test/parse_test.dart
index 9276fc4..b2dda44 100644
--- a/test/parse_test.dart
+++ b/test/parse_test.dart
@@ -260,7 +260,7 @@ void main() {
 
           // This reified type is important in strong mode so that people can
           // safely write "as List<String>".
-          expect(a, TypeMatcher<List<String>>());
+          expect(a, isA<List<String>>());
         });
 
         test(
diff --git a/test/test_utils.dart b/test/test_utils.dart
index 5cfb74a..f19da6d 100644
--- a/test/test_utils.dart
+++ b/test/test_utils.dart
@@ -308,7 +308,7 @@ class AsyncCommand extends Command {
   final takesArguments = false;
 
   @override
-  Future run() => Future.value().then((_) => hasRun = true);
+  Future run() => Future<void>.value().then((_) => hasRun = true);
 }
 
 class AllowAnythingCommand extends Command {