diff --git a/.gitignore b/.gitignore
index 7d006355..01d42c08 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,10 +1,4 @@
-.DS_Store
-packages
+.dart_tool/
+.pub/
 .packages
 pubspec.lock
-.project
-.pub/
-.buildlog
-.settings/
-.idea/
-bazel-*
diff --git a/lib/src/async/command_event.dart b/lib/src/async/command_event.dart
index dea3df0d..0943369c 100644
--- a/lib/src/async/command_event.dart
+++ b/lib/src/async/command_event.dart
@@ -16,12 +16,12 @@ part of webdriver.core;
 class WebDriverCommandEvent {
   final String method;
   final String endPoint;
-  final params;
+  final Object params;
   final StackTrace stackTrace;
   final DateTime startTime;
   final DateTime endTime;
-  final exception;
-  final result;
+  final Object exception;
+  final Object result;
 
   WebDriverCommandEvent(
       {this.method,
diff --git a/lib/src/async/common.dart b/lib/src/async/common.dart
index c0203985..aeafb1fd 100644
--- a/lib/src/async/common.dart
+++ b/lib/src/async/common.dart
@@ -98,7 +98,7 @@ class By {
 
   @override
   String toString() {
-    var constructor;
+    String constructor;
     switch (_using) {
       case 'link text':
         constructor = 'linkText';
diff --git a/lib/src/async/options.dart b/lib/src/async/options.dart
index eb664406..6ad53215 100644
--- a/lib/src/async/options.dart
+++ b/lib/src/async/options.dart
@@ -73,7 +73,7 @@ class Cookie {
       {this.path, this.domain, this.secure, this.expiry});
 
   factory Cookie.fromJson(Map<String, dynamic> json) {
-    var expiry;
+    DateTime expiry;
     if (json['expiry'] is num) {
       expiry = new DateTime.fromMillisecondsSinceEpoch(
           json['expiry'].toInt() * 1000,
diff --git a/lib/src/async/web_driver.dart b/lib/src/async/web_driver.dart
index d34658ff..d08e26a9 100644
--- a/lib/src/async/web_driver.dart
+++ b/lib/src/async/web_driver.dart
@@ -250,7 +250,7 @@ class WebDriver implements SearchContext {
   }
 
   // This is an ugly hack, I know, but I dunno how to cleanly do this.
-  var _previousEvent;
+  WebDriverCommandEvent _previousEvent;
 
   // Performs the request. This will not notify any listeners or
   // onCommandController. This should only be called from
@@ -264,8 +264,8 @@ class WebDriver implements SearchContext {
           (f) => f.library.startsWith('package:webdriver/'),
           terse: true);
     }
-    var result;
-    var exception;
+    Object result;
+    Object exception;
     try {
       if (stepper == null || await stepper.step(method, command, params)) {
         result = await fn();
diff --git a/lib/src/sync/command_event.dart b/lib/src/sync/command_event.dart
index 1fde2e17..2e7e0df3 100644
--- a/lib/src/sync/command_event.dart
+++ b/lib/src/sync/command_event.dart
@@ -15,12 +15,12 @@
 class WebDriverCommandEvent {
   final String method;
   final String endPoint;
-  final params;
+  final Object params;
   final StackTrace stackTrace;
   final DateTime startTime;
   final DateTime endTime;
-  final exception;
-  final result;
+  final Object exception;
+  final Object result;
 
   WebDriverCommandEvent(
       {this.method,
diff --git a/lib/src/sync/common.dart b/lib/src/sync/common.dart
index 3c64db7a..9530e2c9 100644
--- a/lib/src/sync/common.dart
+++ b/lib/src/sync/common.dart
@@ -45,6 +45,7 @@ class SimpleAttributes extends Attributes {
 
   SimpleAttributes(driver, command) : _resolver = new Resolver(driver, command);
 
+  @override
   String operator [](String name) => _resolver.get(name)?.toString();
 }
 
@@ -123,7 +124,7 @@ class By {
 
   @override
   String toString() {
-    var constructor;
+    String constructor;
     switch (using) {
       case 'link text':
         constructor = 'linkText';
@@ -152,4 +153,4 @@ class By {
   @override
   bool operator ==(other) =>
       other is By && other.using == this.using && other.value == this.value;
-}
\ No newline at end of file
+}
diff --git a/lib/src/sync/common_spec/cookies.dart b/lib/src/sync/common_spec/cookies.dart
index 6f3b8a7a..6aa78df3 100644
--- a/lib/src/sync/common_spec/cookies.dart
+++ b/lib/src/sync/common_spec/cookies.dart
@@ -77,7 +77,7 @@ class Cookie {
       {this.path, this.domain, this.secure, this.expiry});
 
   factory Cookie.fromJson(Map<String, dynamic> json) {
-    var expiry;
+    DateTime expiry;
     if (json['expiry'] is num) {
       expiry = new DateTime.fromMillisecondsSinceEpoch(
           json['expiry'].toInt() * 1000,
diff --git a/lib/src/sync/json_wire_spec/web_driver.dart b/lib/src/sync/json_wire_spec/web_driver.dart
index 2924d365..9c3cabbf 100644
--- a/lib/src/sync/json_wire_spec/web_driver.dart
+++ b/lib/src/sync/json_wire_spec/web_driver.dart
@@ -234,8 +234,8 @@ class JsonWireWebDriver implements WebDriver, SearchContext {
           (f) => f.library.startsWith('package:webdriver/'),
           terse: true);
     }
-    var result;
-    var exception;
+    Object result;
+    Object exception;
     try {
       result = fn();
       return result;
diff --git a/lib/src/sync/json_wire_spec/web_element.dart b/lib/src/sync/json_wire_spec/web_element.dart
index c09e4320..357fdf85 100644
--- a/lib/src/sync/json_wire_spec/web_element.dart
+++ b/lib/src/sync/json_wire_spec/web_element.dart
@@ -22,7 +22,6 @@ import '../web_driver.dart';
 import '../web_element.dart';
 
 class JsonWireWebElement implements WebElement, SearchContext {
-  final String _elementPrefix;
   final Resolver _resolver;
 
   @override
@@ -48,8 +47,7 @@ class JsonWireWebElement implements WebElement, SearchContext {
 
   JsonWireWebElement(this.driver, this.id,
       [this.context, this.locator, this.index])
-      : _elementPrefix = 'element/$id',
-        _resolver = new Resolver(driver, 'element/$id');
+      : _resolver = new Resolver(driver, 'element/$id');
 
   @override
   void click() {
@@ -175,14 +173,14 @@ class _ElementAttributes extends Attributes {
   _ElementAttributes(this.element);
 
   @override
-  String operator [](String name) => element.driver.execute("""
+  String operator [](String name) => element.driver.execute('''
     var attr = arguments[0].attributes["$name"];
     if(attr) {
       return attr.value;
     }
 
     return null;
-    """, [element])?.toString();
+    ''', [element])?.toString();
 }
 
 class _ElementComputedStyle extends Attributes {
@@ -209,4 +207,4 @@ class _ElementProperties extends Attributes {
 
 /// Convert hyphenated-properties to camelCase.
 String _cssPropName(String name) => name.splitMapJoin(new RegExp(r'-(\w)'),
-    onMatch: (m) => m.group(1).toUpperCase(), onNonMatch: (m) => m);
\ No newline at end of file
+    onMatch: (m) => m.group(1).toUpperCase(), onNonMatch: (m) => m);
diff --git a/lib/src/sync/w3c_spec/element_finder.dart b/lib/src/sync/w3c_spec/element_finder.dart
index db000a5d..c697ad99 100644
--- a/lib/src/sync/w3c_spec/element_finder.dart
+++ b/lib/src/sync/w3c_spec/element_finder.dart
@@ -31,8 +31,8 @@ class ElementFinder {
   /// In principle, W3C spec implementations should be nearly the same as
   /// the existing JSON wire spec. In practice compliance is uneven.
   Map<String, String> _byToJson(By by) {
-    var using;
-    var value;
+    String using;
+    String value;
 
     switch (by.using) {
       case 'id': // This doesn't exist in the W3C spec.
diff --git a/lib/src/sync/w3c_spec/web_driver.dart b/lib/src/sync/w3c_spec/web_driver.dart
index f8d9180b..52b737f3 100644
--- a/lib/src/sync/w3c_spec/web_driver.dart
+++ b/lib/src/sync/w3c_spec/web_driver.dart
@@ -211,8 +211,8 @@ class W3cWebDriver implements WebDriver, SearchContext {
           (f) => f.library.startsWith('package:webdriver/'),
           terse: true);
     }
-    var result;
-    var exception;
+    Object result;
+    Object exception;
     try {
       result = fn();
       return result;
diff --git a/lib/src/sync/window.dart b/lib/src/sync/window.dart
index 78b56d3a..e7033b11 100644
--- a/lib/src/sync/window.dart
+++ b/lib/src/sync/window.dart
@@ -50,7 +50,4 @@ abstract class Window {
 
   /// Sets the window as active.
   void setAsActive();
-
-  @override
-  bool operator ==(other);
 }
diff --git a/pubspec.yaml b/pubspec.yaml
index 587a2ef3..a8b341b6 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -3,9 +3,9 @@ version: 2.0.0-dev
 authors:
   - Marc Fisher II <fisherii@google.com>
   - Matt Staats<staats@google.com>
-description: >
-  Provides WebDriver bindings for Dart. These support the WebDriver JSON interface
-  and the W3C spec and require the use of the WebDriver remote server.
+description: >-
+  Provides WebDriver bindings for Dart. These support the WebDriver JSON
+  interface and the W3C spec and require the use of the WebDriver remote server.
 homepage: https://github.com/google/webdriver.dart
 environment:
   sdk: '>=2.0.0-dev.23.0'
diff --git a/test/async_command_event_test.dart b/test/async_command_event_test.dart
index e4516864..398ccf2d 100644
--- a/test/async_command_event_test.dart
+++ b/test/async_command_event_test.dart
@@ -15,6 +15,8 @@
 @TestOn('vm')
 library webdriver.command_event_test;
 
+import 'dart:async';
+
 import 'package:stack_trace/stack_trace.dart';
 import 'package:test/test.dart';
 import 'package:webdriver/async_core.dart';
@@ -27,7 +29,7 @@ void main() {
     WebDriver driver;
 
     var events = <WebDriverCommandEvent>[];
-    var sub;
+    StreamSubscription sub;
 
     setUp(() async {
       driver = await config.createTestDriver();
diff --git a/test/support/async_test.dart b/test/support/async_test.dart
index 1530b19a..aa7e2d73 100644
--- a/test/support/async_test.dart
+++ b/test/support/async_test.dart
@@ -107,8 +107,7 @@ void main() {
     });
 
     test('throws if condition throws and timeouts', () async {
-      var exception;
-
+      Object exception;
       try {
         await clock.waitFor(() => throw 'an exception');
       } catch (e) {
@@ -118,7 +117,7 @@ void main() {
     });
 
     test('throws if condition never matches', () async {
-      var exception;
+      Object exception;
       try {
         await clock.waitFor(() => null, matcher: isNotNull);
       } catch (e) {
@@ -134,8 +133,7 @@ void main() {
     });
 
     test('works with Future exceptions', () async {
-      var exception;
-
+      Object exception;
       try {
         await clock.waitFor(() => new Future.error('an exception'));
       } catch (e) {
@@ -160,7 +158,7 @@ void main() {
 
     test('sanity test with real Clock -- throws', () async {
       var clock = const Clock();
-      var exception;
+      Object exception;
       try {
         await clock.waitFor(() => throw 'an exception');
       } catch (e) {
@@ -171,7 +169,7 @@ void main() {
 
     test('sanity test with real Clock -- never matches', () async {
       var clock = const Clock();
-      var exception;
+      Object exception;
       try {
         await clock.waitFor(() => null, matcher: isNotNull);
       } catch (e) {
diff --git a/test/sync/keyboard.dart b/test/sync/keyboard.dart
index a7dbe382..80d0f8b5 100644
--- a/test/sync/keyboard.dart
+++ b/test/sync/keyboard.dart
@@ -74,4 +74,4 @@ void runTests(config.createTestDriver createTestDriver) {
       expect(textInput.properties['value'], 'xxx');
     });
   }, timeout: const Timeout(const Duration(minutes: 2)));
-}
\ No newline at end of file
+}