diff --git a/tutorial/dart/client/.analysis_options b/tutorial/dart/client/.analysis_options
new file mode 100644
index 0000000..a10d4c5
--- /dev/null
+++ b/tutorial/dart/client/.analysis_options
@@ -0,0 +1,2 @@
+analyzer:
+  strong-mode: true
diff --git a/tutorial/dart/client/pubspec.yaml b/tutorial/dart/client/pubspec.yaml
index 4bd3394..db64afc 100644
--- a/tutorial/dart/client/pubspec.yaml
+++ b/tutorial/dart/client/pubspec.yaml
@@ -22,7 +22,7 @@
 homepage: http://thrift.apache.org
 
 environment:
-  sdk: ^1.12.0
+  sdk: ">=1.13.0 <2.0.0"
 
 dependencies:
   browser: ^0.10.0
diff --git a/tutorial/dart/console_client/.analysis_options b/tutorial/dart/console_client/.analysis_options
new file mode 100644
index 0000000..a10d4c5
--- /dev/null
+++ b/tutorial/dart/console_client/.analysis_options
@@ -0,0 +1,2 @@
+analyzer:
+  strong-mode: true
diff --git a/tutorial/dart/console_client/pubspec.yaml b/tutorial/dart/console_client/pubspec.yaml
index 1423ed2..cea13ac 100644
--- a/tutorial/dart/console_client/pubspec.yaml
+++ b/tutorial/dart/console_client/pubspec.yaml
@@ -21,8 +21,10 @@
   A Dart console client to implementation of the Apache Thrift tutorial
 author: Apache Thrift Developers <dev@thrift.apache.org>
 homepage: http://thrift.apache.org
+
 environment:
-  sdk: ^1.12.0
+  sdk: ">=1.13.0 <2.0.0"
+
 dependencies:
   args: ^0.13.0
   collection: ^1.1.0
diff --git a/tutorial/dart/server/.analysis_options b/tutorial/dart/server/.analysis_options
new file mode 100644
index 0000000..a10d4c5
--- /dev/null
+++ b/tutorial/dart/server/.analysis_options
@@ -0,0 +1,2 @@
+analyzer:
+  strong-mode: true
diff --git a/tutorial/dart/server/pubspec.yaml b/tutorial/dart/server/pubspec.yaml
index cdb2dc7..4833a4a 100644
--- a/tutorial/dart/server/pubspec.yaml
+++ b/tutorial/dart/server/pubspec.yaml
@@ -20,8 +20,10 @@
 description: A Dart server to support the Apache Thrift tutorial
 author: Apache Thrift Developers <dev@thrift.apache.org>
 homepage: http://thrift.apache.org
+
 environment:
-  sdk: ^1.12.0
+  sdk: ">=1.13.0 <2.0.0"
+
 dependencies:
   args: ^0.13.0
   shared: