diff --git a/.dart_tool/package_config.json b/.dart_tool/package_config.json
index 3c57af1bd0f..f0139e405dd 100644
--- a/.dart_tool/package_config.json
+++ b/.dart_tool/package_config.json
@@ -76,7 +76,7 @@
       "name": "analysis_server_client",
       "rootUri": "../pkg/analysis_server_client",
       "packageUri": "lib/",
-      "languageVersion": "2.8"
+      "languageVersion": "2.12"
     },
     {
       "name": "analyzer",
diff --git a/pkg/analysis_server_client/CHANGELOG.md b/pkg/analysis_server_client/CHANGELOG.md
index 43563a17cdc..d1f5f3f5f0d 100644
--- a/pkg/analysis_server_client/CHANGELOG.md
+++ b/pkg/analysis_server_client/CHANGELOG.md
@@ -1,3 +1,6 @@
+# 2.0.0-dev
+* Stable null safety release.
+
 # 1.1.3
  * Supports changes made to the Analysis Server protocol through Dart 2.8.0
  * Updates to use pedantic 1.9.0 and some internal refactoring. 
diff --git a/pkg/analysis_server_client/example/example.dart b/pkg/analysis_server_client/example/example.dart
index 41af85cdc4a..faddfd58747 100644
--- a/pkg/analysis_server_client/example/example.dart
+++ b/pkg/analysis_server_client/example/example.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 import 'dart:async';
 import 'dart:io' show Directory, Platform, ProcessSignal, exit;
 
diff --git a/pkg/analysis_server_client/lib/handler/connection_handler.dart b/pkg/analysis_server_client/lib/handler/connection_handler.dart
index 107b361cac9..96045c028ff 100644
--- a/pkg/analysis_server_client/lib/handler/connection_handler.dart
+++ b/pkg/analysis_server_client/lib/handler/connection_handler.dart
@@ -6,6 +6,8 @@
 // To regenerate the file, use the script
 // "pkg/analysis_server/tool/spec/generate_files".
 
+// @dart = 2.9
+
 import 'dart:async';
 
 import 'package:analysis_server_client/handler/notification_handler.dart';
diff --git a/pkg/analysis_server_client/lib/protocol.dart b/pkg/analysis_server_client/lib/protocol.dart
index 7a1059b49c1..3879201471a 100644
--- a/pkg/analysis_server_client/lib/protocol.dart
+++ b/pkg/analysis_server_client/lib/protocol.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 export 'package:analysis_server_client/src/protocol/protocol_base.dart';
 export 'package:analysis_server_client/src/protocol/protocol_common.dart';
 export 'package:analysis_server_client/src/protocol/protocol_constants.dart';
diff --git a/pkg/analysis_server_client/lib/server.dart b/pkg/analysis_server_client/lib/server.dart
index d11442ccf4c..ae6d8f0819f 100644
--- a/pkg/analysis_server_client/lib/server.dart
+++ b/pkg/analysis_server_client/lib/server.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
diff --git a/pkg/analysis_server_client/lib/src/protocol/protocol_base.dart b/pkg/analysis_server_client/lib/src/protocol/protocol_base.dart
index 8fa072df6b6..b855045454e 100644
--- a/pkg/analysis_server_client/lib/src/protocol/protocol_base.dart
+++ b/pkg/analysis_server_client/lib/src/protocol/protocol_base.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 /// Support for client code that needs to interact with the requests, responses
 /// and notifications that are part of the analysis server's wire protocol.
 import 'dart:convert' hide JsonDecoder;
diff --git a/pkg/analysis_server_client/lib/src/protocol/protocol_common.dart b/pkg/analysis_server_client/lib/src/protocol/protocol_common.dart
index 13e33f1b628..213f857bf9f 100644
--- a/pkg/analysis_server_client/lib/src/protocol/protocol_common.dart
+++ b/pkg/analysis_server_client/lib/src/protocol/protocol_common.dart
@@ -6,6 +6,8 @@
 // To regenerate the file, use the script
 // "pkg/analysis_server/tool/spec/generate_files".
 
+// @dart = 2.9
+
 import 'dart:convert' hide JsonDecoder;
 
 import 'package:analysis_server_client/src/protocol/protocol_util.dart';
diff --git a/pkg/analysis_server_client/lib/src/protocol/protocol_internal.dart b/pkg/analysis_server_client/lib/src/protocol/protocol_internal.dart
index e35a40d6a2d..4758cf6d7e6 100644
--- a/pkg/analysis_server_client/lib/src/protocol/protocol_internal.dart
+++ b/pkg/analysis_server_client/lib/src/protocol/protocol_internal.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 import 'dart:collection';
 import 'dart:convert' hide JsonDecoder;
 
diff --git a/pkg/analysis_server_client/lib/src/protocol/protocol_util.dart b/pkg/analysis_server_client/lib/src/protocol/protocol_util.dart
index 02e8c7506c9..95ff9e8ec25 100644
--- a/pkg/analysis_server_client/lib/src/protocol/protocol_util.dart
+++ b/pkg/analysis_server_client/lib/src/protocol/protocol_util.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 /// Jenkins hash function, optimized for small integers.
 ///
 /// Static methods borrowed from sdk/lib/math/jenkins_smi_hash.dart. Non-static
diff --git a/pkg/analysis_server_client/lib/src/server_base.dart b/pkg/analysis_server_client/lib/src/server_base.dart
index 39e9c1d15c7..7aea73ef86f 100644
--- a/pkg/analysis_server_client/lib/src/server_base.dart
+++ b/pkg/analysis_server_client/lib/src/server_base.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
diff --git a/pkg/analysis_server_client/pubspec.yaml b/pkg/analysis_server_client/pubspec.yaml
index 0589bc3f51e..8b9c79522d2 100644
--- a/pkg/analysis_server_client/pubspec.yaml
+++ b/pkg/analysis_server_client/pubspec.yaml
@@ -1,15 +1,15 @@
 name: analysis_server_client
-version: 1.1.3
+version: 2.0.0-dev
 description:
   A client wrapper over analysis_server.
   Instances of the class [Server] manage a connection to a server process,
   and facilitate communication to and from the server.
 homepage: https://github.com/dart-lang/sdk/tree/master/pkg/analysis_server_client
 environment:
-  sdk: '>=2.8.0 <3.0.0'
+  sdk: '>=2.12.0 <3.0.0'
 dependencies:
-  path: ^1.7.0
-  pub_semver: ^1.4.4
+  path: ^1.8.0
+  pub_semver: ^2.0.0
 dev_dependencies:
   analyzer:
     path: ../analyzer
diff --git a/pkg/analysis_server_client/test/all.dart b/pkg/analysis_server_client/test/all.dart
index bd97ea7c1bb..d510ab268fe 100644
--- a/pkg/analysis_server_client/test/all.dart
+++ b/pkg/analysis_server_client/test/all.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 import 'live_test.dart' as live;
 import 'server_test.dart' as server;
 import 'verify_sorted_test.dart' as verify_sorted;
diff --git a/pkg/analysis_server_client/test/live_test.dart b/pkg/analysis_server_client/test/live_test.dart
index e9ed329b8cc..80b593d761b 100644
--- a/pkg/analysis_server_client/test/live_test.dart
+++ b/pkg/analysis_server_client/test/live_test.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 import 'package:analysis_server_client/handler/connection_handler.dart';
 import 'package:analysis_server_client/handler/notification_handler.dart';
 import 'package:analysis_server_client/listener/server_listener.dart';
diff --git a/pkg/analysis_server_client/test/server_test.dart b/pkg/analysis_server_client/test/server_test.dart
index 2442e5b1158..32aadc10392 100644
--- a/pkg/analysis_server_client/test/server_test.dart
+++ b/pkg/analysis_server_client/test/server_test.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
diff --git a/pkg/analysis_server_client/test/verify_sorted_test.dart b/pkg/analysis_server_client/test/verify_sorted_test.dart
index 5a19d51174d..6841a86197c 100644
--- a/pkg/analysis_server_client/test/verify_sorted_test.dart
+++ b/pkg/analysis_server_client/test/verify_sorted_test.dart
@@ -2,6 +2,8 @@
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+// @dart = 2.9
+
 import 'package:analysis_server/src/services/correction/sort_members.dart';
 import 'package:analyzer/dart/analysis/analysis_context_collection.dart';
 import 'package:analyzer/dart/analysis/results.dart';