diff --git a/pkg/dds/CHANGELOG.md b/pkg/dds/CHANGELOG.md
index 89c1eac711d..8cef29266b2 100644
--- a/pkg/dds/CHANGELOG.md
+++ b/pkg/dds/CHANGELOG.md
@@ -1,6 +1,7 @@
 # 5.0.1-wip
 
 - Widen the dependency on `package:shelf_web_socket`.
+- Require Dart SDK v. 3.5.0 or higher.
 
 # 5.0.0
 - [DAP] The debug adapter no longer spawns its own in-process copy of DDS, instead relying on one started by the Dart VM (or `Flutter`). This means the `enableDds` and `enableAuthCodes` arguments to the `DartDebugAdapter` base class have been deprecated and have any effect. Suppressing DDS (or auth codes) should be done in launch configuration (for example using `vmAdditionalArgs` or `toolArgs` depending on the target tool).
diff --git a/pkg/dds/lib/src/dds_impl.dart b/pkg/dds/lib/src/dds_impl.dart
index 34ee2a82362..7c2ba6667ed 100644
--- a/pkg/dds/lib/src/dds_impl.dart
+++ b/pkg/dds/lib/src/dds_impl.dart
@@ -388,7 +388,7 @@ class DartDevelopmentServiceImpl implements DartDevelopmentService {
         // If DDS is serving DevTools, install the DevTools handlers and
         // forward any unhandled HTTP requests to the VM service.
         final String buildDir =
-            _devToolsConfiguration!.customBuildDirectoryPath.toFilePath();
+            _devToolsConfiguration.customBuildDirectoryPath.toFilePath();
         return defaultHandler(
           dds: this,
           buildDir: buildDir,
diff --git a/pkg/dds/pubspec.yaml b/pkg/dds/pubspec.yaml
index 93b01ebf38a..a321f02dc3b 100644
--- a/pkg/dds/pubspec.yaml
+++ b/pkg/dds/pubspec.yaml
@@ -6,7 +6,8 @@ description: >-
 repository: https://github.com/dart-lang/sdk/tree/main/pkg/dds
 
 environment:
-  sdk: '>=3.0.0 <4.0.0'
+  sdk: ^3.5.0
+
 
 dependencies:
   args: ^2.0.0
diff --git a/pkg/dds_service_extensions/CHANGELOG.md b/pkg/dds_service_extensions/CHANGELOG.md
index f8508006ab2..019258b20b1 100644
--- a/pkg/dds_service_extensions/CHANGELOG.md
+++ b/pkg/dds_service_extensions/CHANGELOG.md
@@ -1,3 +1,6 @@
+# 2.0.2-wip
+- Require dart sdk v. 3.5.0 or higher.
+
 # 2.0.1
 - Update `vm_service` to `>=14.0.0 <16.0.0`.
 
diff --git a/pkg/dds_service_extensions/pubspec.yaml b/pkg/dds_service_extensions/pubspec.yaml
index b4d87b8e9d5..ecbe5fb7ece 100644
--- a/pkg/dds_service_extensions/pubspec.yaml
+++ b/pkg/dds_service_extensions/pubspec.yaml
@@ -1,12 +1,13 @@
 name: dds_service_extensions
-version: 2.0.1
+version: 2.0.2-wip
 description: >-
   Extension methods for `package:vm_service`, used to make requests a
   Dart Development Service (DDS) instance.
 repository: https://github.com/dart-lang/sdk/tree/main/pkg/dds_service_extensions
 
 environment:
-  sdk: ^3.0.0
+  sdk: ^3.5.0
+
 
 dependencies:
   async: ^2.4.1