diff --git a/.analysis_options b/.analysis_options
new file mode 100644
index 0000000..a10d4c5
--- /dev/null
+++ b/.analysis_options
@@ -0,0 +1,2 @@
+analyzer:
+  strong-mode: true
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3066293..4872d79 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+## 0.10.1+1
+
+* Fix all strong mode warnings.
+
 ## 0.10.1
 
 * Add a `mapUrl` named argument to `parse` and `parseJson`. This argument is
diff --git a/lib/parser.dart b/lib/parser.dart
index a9fcff5..b659654 100644
--- a/lib/parser.dart
+++ b/lib/parser.dart
@@ -182,7 +182,7 @@
     var names = new LinkedHashMap<String, int>();
 
     var lineNum;
-    var targetEntries;
+    List<TargetEntry> targetEntries;
     for (var sourceEntry in sourceEntries) {
       if (lineNum == null || sourceEntry.target.line > lineNum) {
         lineNum = sourceEntry.target.line;
@@ -212,8 +212,8 @@
 
   SingleMapping.fromJson(Map map, {mapUrl})
       : targetUrl = map['file'],
-        urls = map['sources'],
-        names = map['names'],
+        urls = new List<String>.from(map['sources']),
+        names = new List<String>.from(map['names']),
         sourceRoot = map['sourceRoot'],
         lines = <TargetLineEntry>[],
         _mapUrl = mapUrl is String ? Uri.parse(mapUrl) : mapUrl {
diff --git a/pubspec.yaml b/pubspec.yaml
index 86015d5..e8dd794 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: source_maps
-version: 0.10.2-dev
+version: 0.10.1+1
 author: Dart Team <misc@dartlang.org>
 description: Library to programmatically manipulate source map files.
 homepage: http://github.com/dart-lang/source_maps