diff --git a/CHANGELOG.md b/CHANGELOG.md
index 866e5ba8..b78b1bb3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+# 2.0.0-alpha.1
+* Refactor `params` to `Map<String, dynamic>`.
+
 # 2.0.0-alpha
 * Depend on Dart 2.
 * Depend on Angel 2.
diff --git a/lib/angel_client.dart b/lib/angel_client.dart
index 2f89bd8f..fa1ff0bf 100644
--- a/lib/angel_client.dart
+++ b/lib/angel_client.dart
@@ -8,13 +8,13 @@ import 'package:http/src/response.dart' as http;
 export 'package:angel_http_exception/angel_http_exception.dart';
 
 /// A function that configures an [Angel] client in some way.
-typedef Future AngelConfigurer(Angel app);
+typedef FutureOr AngelConfigurer(Angel app);
 
 /// A function that deserializes data received from the server.
 ///
 /// This is only really necessary in the browser, where `json_god`
 /// doesn't work.
-typedef AngelDeserializer(x);
+typedef T AngelDeserializer<T>(x);
 
 /// Represents an Angel server that we are querying.
 abstract class Angel {
@@ -45,7 +45,8 @@ abstract class Angel {
   /// Logs the current user out of the application.
   Future logout();
 
-  Service service(String path, {Type type, AngelDeserializer deserializer});
+  Service<Id, Data> service<Id, Data>(String path,
+      {Type type, AngelDeserializer<Data> deserializer});
 
   Future<http.Response> delete(String url, {Map<String, String> headers});
 
@@ -92,24 +93,24 @@ class AngelAuthResult {
 }
 
 /// Queries a service on an Angel server, with the same API.
-abstract class Service {
+abstract class Service<Id, Data> {
   /// Fired on `indexed` events.
   Stream get onIndexed;
 
   /// Fired on `read` events.
-  Stream get onRead;
+  Stream<Data> get onRead;
 
   /// Fired on `created` events.
-  Stream get onCreated;
+  Stream<Data> get onCreated;
 
   /// Fired on `modified` events.
-  Stream get onModified;
+  Stream<Data> get onModified;
 
   /// Fired on `updated` events.
-  Stream get onUpdated;
+  Stream<Data> get onUpdated;
 
   /// Fired on `removed` events.
-  Stream get onRemoved;
+  Stream<Data> get onRemoved;
 
   /// The Angel instance powering this service.
   Angel get app;
@@ -117,26 +118,26 @@ abstract class Service {
   Future close();
 
   /// Retrieves all resources.
-  Future index([Map params]);
+  Future index([Map<String, dynamic> params]);
 
   /// Retrieves the desired resource.
-  Future read(id, [Map params]);
+  Future read(Id id, [Map<String, dynamic> params]);
 
   /// Creates a resource.
-  Future create(data, [Map params]);
+  Future create(Data data, [Map<String, dynamic> params]);
 
   /// Modifies a resource.
-  Future modify(id, data, [Map params]);
+  Future modify(Id id, Data data, [Map<String, dynamic> params]);
 
   /// Overwrites a resource.
-  Future update(id, data, [Map params]);
+  Future update(Id id, Data data, [Map<String, dynamic> params]);
 
   /// Removes the given resource.
-  Future remove(id, [Map params]);
+  Future remove(Id id, [Map<String, dynamic> params]);
 }
 
 /// A [List] that automatically updates itself whenever the referenced [service] fires an event.
-class ServiceList extends DelegatingList {
+class ServiceList<Id, Data> extends DelegatingList {
   /// A field name used to compare [Map] by ID.
   final String idField;
 
@@ -150,9 +151,10 @@ class ServiceList extends DelegatingList {
   /// Defaults to comparing the [idField] of `Map` instances.
   final Equality _compare;
 
-  final Service service;
+  final Service<Id, Data> service;
 
-  final StreamController<ServiceList> _onChange = new StreamController();
+  final StreamController<ServiceList<Id, Data>> _onChange =
+      new StreamController();
   final List<StreamSubscription> _subs = [];
 
   ServiceList(this.service,
@@ -175,7 +177,7 @@ class ServiceList extends DelegatingList {
     }));
 
     // Modified/Updated
-    handleModified(item) {
+    handleModified(Data item) {
       var indices = <int>[];
 
       for (int i = 0; i < length; i++) {
@@ -202,7 +204,7 @@ class ServiceList extends DelegatingList {
   }
 
   /// Fires whenever the underlying [service] fires a change event.
-  Stream<ServiceList> get onChange => _onChange.stream;
+  Stream<ServiceList<Id, Data>> get onChange => _onChange.stream;
 
   Future close() async {
     _onChange.close();
diff --git a/lib/base_angel_client.dart b/lib/base_angel_client.dart
index 96fb0308..13f7f79b 100644
--- a/lib/base_angel_client.dart
+++ b/lib/base_angel_client.dart
@@ -16,7 +16,7 @@ const Map<String, String> _writeHeaders = const {
   'Content-Type': 'application/json'
 };
 
-_buildQuery(Map params) {
+_buildQuery(Map<String, dynamic> params) {
   if (params == null || params.isEmpty || params['query'] is! Map) return "";
 
   List<String> query = [];
@@ -191,9 +191,10 @@ abstract class BaseAngelClient extends Angel {
   }
 
   @override
-  Service service(String path, {Type type, AngelDeserializer deserializer}) {
+  Service<Id, Data> service<Id, Data>(String path,
+      {Type type, AngelDeserializer<Data> deserializer}) {
     String uri = path.toString().replaceAll(straySlashes, "");
-    var s = new BaseAngelService(client, this, '$basePath/$uri',
+    var s = new BaseAngelService<Id, Data>(client, this, '$basePath/$uri',
         deserializer: deserializer);
     _services.add(s);
     return s;
@@ -240,15 +241,15 @@ abstract class BaseAngelClient extends Angel {
   }
 }
 
-class BaseAngelService extends Service {
+class BaseAngelService<Id, Data> extends Service<Id, Data> {
   @override
   final BaseAngelClient app;
   final String basePath;
   final http.BaseClient client;
-  final AngelDeserializer deserializer;
+  final AngelDeserializer<Data> deserializer;
 
-  final StreamController _onIndexed = new StreamController(),
-      _onRead = new StreamController(),
+  final StreamController _onIndexed = new StreamController();
+  final StreamController<Data> _onRead = new StreamController(),
       _onCreated = new StreamController(),
       _onModified = new StreamController(),
       _onUpdated = new StreamController(),
@@ -258,19 +259,19 @@ class BaseAngelService extends Service {
   Stream get onIndexed => _onIndexed.stream;
 
   @override
-  Stream get onRead => _onRead.stream;
+  Stream<Data> get onRead => _onRead.stream;
 
   @override
-  Stream get onCreated => _onCreated.stream;
+  Stream<Data> get onCreated => _onCreated.stream;
 
   @override
-  Stream get onModified => _onModified.stream;
+  Stream<Data> get onModified => _onModified.stream;
 
   @override
-  Stream get onUpdated => _onUpdated.stream;
+  Stream<Data> get onUpdated => _onUpdated.stream;
 
   @override
-  Stream get onRemoved => _onRemoved.stream;
+  Stream<Data> get onRemoved => _onRemoved.stream;
 
   @override
   Future close() async {
@@ -284,8 +285,8 @@ class BaseAngelService extends Service {
 
   BaseAngelService(this.client, this.app, this.basePath, {this.deserializer});
 
-  deserialize(x) {
-    return deserializer != null ? deserializer(x) : x;
+  Data deserialize(x) {
+    return deserializer != null ? deserializer(x) : x as Data;
   }
 
   makeBody(x) {
@@ -301,7 +302,7 @@ class BaseAngelService extends Service {
   }
 
   @override
-  Future index([Map params]) async {
+  Future index([Map<String, dynamic> params]) async {
     final response = await app.sendUnstreamed(
         'GET', '$basePath${_buildQuery(params)}', _readHeaders);
 
@@ -316,7 +317,7 @@ class BaseAngelService extends Service {
       final v = json.decode(response.body);
 
       if (v is! List) {
-        _onIndexed.add(v);
+        _onIndexed.add(v as Data);
         return v;
       }
 
@@ -332,7 +333,7 @@ class BaseAngelService extends Service {
   }
 
   @override
-  Future read(id, [Map params]) async {
+  Future read(id, [Map<String, dynamic> params]) async {
     final response = await app.sendUnstreamed(
         'GET', '$basePath/$id${_buildQuery(params)}', _readHeaders);
 
@@ -356,7 +357,7 @@ class BaseAngelService extends Service {
   }
 
   @override
-  Future create(data, [Map params]) async {
+  Future create(data, [Map<String, dynamic> params]) async {
     final response = await app.sendUnstreamed('POST',
         '$basePath/${_buildQuery(params)}', _writeHeaders, makeBody(data));
 
@@ -380,7 +381,7 @@ class BaseAngelService extends Service {
   }
 
   @override
-  Future modify(id, data, [Map params]) async {
+  Future modify(id, data, [Map<String, dynamic> params]) async {
     final response = await app.sendUnstreamed('PATCH',
         '$basePath/$id${_buildQuery(params)}', _writeHeaders, makeBody(data));
 
@@ -404,7 +405,7 @@ class BaseAngelService extends Service {
   }
 
   @override
-  Future update(id, data, [Map params]) async {
+  Future update(id, data, [Map<String, dynamic> params]) async {
     final response = await app.sendUnstreamed('POST',
         '$basePath/$id${_buildQuery(params)}', _writeHeaders, makeBody(data));
 
@@ -428,7 +429,7 @@ class BaseAngelService extends Service {
   }
 
   @override
-  Future remove(id, [Map params]) async {
+  Future remove(id, [Map<String, dynamic> params]) async {
     final response = await app.sendUnstreamed(
         'DELETE', '$basePath/$id${_buildQuery(params)}', _readHeaders);
 
diff --git a/lib/io.dart b/lib/io.dart
index 538d9fe6..cb50df37 100644
--- a/lib/io.dart
+++ b/lib/io.dart
@@ -15,9 +15,10 @@ class Rest extends BaseAngelClient {
   Rest(String path) : super(new http.Client() as http.BaseClient, path);
 
   @override
-  Service service(String path, {Type type, AngelDeserializer deserializer}) {
+  Service<Id, Data> service<Id, Data>(String path,
+      {Type type, AngelDeserializer deserializer}) {
     String uri = path.replaceAll(straySlashes, "");
-    var s = new RestService(client, this, "$basePath/$uri", type);
+    var s = new RestService<Id, Data>(client, this, "$basePath/$uri", type);
     _services.add(s);
     return s;
   }
@@ -37,7 +38,7 @@ class Rest extends BaseAngelClient {
 }
 
 /// Queries an Angel service via REST.
-class RestService extends BaseAngelService {
+class RestService<Id, Data> extends BaseAngelService<Id, Data> {
   final Type type;
 
   RestService(
@@ -45,14 +46,14 @@ class RestService extends BaseAngelService {
       : super(client, app, url);
 
   @override
-  deserialize(x) {
+  Data deserialize(x) {
     if (type != null) {
       return x.runtimeType == type
-          ? x
-          : god.deserializeDatum(x, outputType: type);
+          ? x as Data
+          : god.deserializeDatum(x, outputType: type) as Data;
     }
 
-    return x;
+    return x as Data;
   }
 
   @override
diff --git a/pubspec.yaml b/pubspec.yaml
index 2870cf10..dbab4f54 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,5 +1,5 @@
 name: angel_client
-version: 2.0.0-alpha
+version: 2.0.0-alpha.1
 description: Client library for the Angel framework.
 author: Tobe O <thosakwe@gmail.com>
 homepage: https://github.com/angel-dart/angel_client