diff --git a/.github/workflows/stale.yml b/.github/workflows/stale.yml
new file mode 100644
index 000000000..ee1a64359
--- /dev/null
+++ b/.github/workflows/stale.yml
@@ -0,0 +1,19 @@
+name: 'Close stale issues and PR'
+on:
+  schedule:
+    - cron: '30 1 * * *'
+
+jobs:
+  stale:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/stale@v3
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          stale-issue-message: 'This issue is stale because it has been open 30 days with no activity. Remove stale label or comment or this will be closed in 5 days.'
+          stale-pr-message: 'This PR is stale because it has been open 45 days with no activity. Remove stale label or comment or this will be closed in 10 days.'
+          close-issue-message: 'This issue was closed because it has been stalled for 5 days with no activity.'
+          days-before-stale: 30
+          days-before-close: 5
+          days-before-pr-close: -1
+
diff --git a/example/lib/pages/animated_map_controller.dart b/example/lib/pages/animated_map_controller.dart
index e5d9eab46..4deb55ce1 100644
--- a/example/lib/pages/animated_map_controller.dart
+++ b/example/lib/pages/animated_map_controller.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
@@ -29,7 +29,7 @@ class AnimatedMapControllerPageState extends State<AnimatedMapControllerPage>
   static LatLng paris = LatLng(48.8566, 2.3522);
   static LatLng dublin = LatLng(53.3498, -6.2603);
 
-  MapController mapController;
+  late MapController mapController;
 
   @override
   void initState() {
diff --git a/example/lib/pages/circle.dart b/example/lib/pages/circle.dart
index 723776bf2..01eb386c7 100644
--- a/example/lib/pages/circle.dart
+++ b/example/lib/pages/circle.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/custom_crs/custom_crs.dart b/example/lib/pages/custom_crs/custom_crs.dart
index f37ab02d7..0cc0e8682 100644
--- a/example/lib/pages/custom_crs/custom_crs.dart
+++ b/example/lib/pages/custom_crs/custom_crs.dart
@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_map/plugin_api.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 import 'package:proj4dart/proj4dart.dart' as proj4;
 
 import '../../widgets/drawer.dart';
@@ -14,30 +14,31 @@ class CustomCrsPage extends StatefulWidget {
 }
 
 class _CustomCrsPageState extends State<CustomCrsPage> {
-  Proj4Crs epsg3413CRS;
+  late Proj4Crs epsg3413CRS;
 
-  double maxZoom;
+  double? maxZoom;
 
   // Define start center
   proj4.Point point = proj4.Point(x: 65.05166470332148, y: -19.171744826394896);
 
   String initText = 'Map centered to';
 
-  proj4.Projection epsg4326;
+  late proj4.Projection epsg4326;
 
-  proj4.Projection epsg3413;
+  late proj4.Projection epsg3413;
 
   @override
   void initState() {
     super.initState();
 
     // EPSG:4326 is a predefined projection ships with proj4dart
-    epsg4326 = proj4.Projection('EPSG:4326');
+    epsg4326 = proj4.Projection.get('EPSG:4326')!;
 
     // EPSG:3413 is a user-defined projection from a valid Proj4 definition string
     // From: http://epsg.io/3413, proj definition: http://epsg.io/3413.proj4
     // Find Projection by name or define it if not exists
-    epsg3413 = proj4.Projection('EPSG:3413') ??
+    // TODO the warning here will go away as soon as proj4 is migrated to null safety
+    epsg3413 = proj4.Projection.get('EPSG:3413') ??
         proj4.Projection.add('EPSG:3413',
             '+proj=stere +lat_0=90 +lat_ts=70 +lon_0=-45 +k=1 +x_0=0 +y_0=0 +datum=WGS84 +units=m +no_defs');
 
diff --git a/example/lib/pages/esri.dart b/example/lib/pages/esri.dart
index d316b0b88..7976e133e 100644
--- a/example/lib/pages/esri.dart
+++ b/example/lib/pages/esri.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/home.dart b/example/lib/pages/home.dart
index 621a3fbc3..9e4146ed3 100644
--- a/example/lib/pages/home.dart
+++ b/example/lib/pages/home.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/interactive_test_page.dart b/example/lib/pages/interactive_test_page.dart
index f76af65c9..7bc127622 100644
--- a/example/lib/pages/interactive_test_page.dart
+++ b/example/lib/pages/interactive_test_page.dart
@@ -2,7 +2,7 @@ import 'dart:async';
 
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
@@ -16,12 +16,12 @@ class InteractiveTestPage extends StatefulWidget {
 }
 
 class _InteractiveTestPageState extends State<InteractiveTestPage> {
-  MapController mapController;
+  late MapController mapController;
 
   // Enable pinchZoom and doubleTapZoomBy by default
   int flags = InteractiveFlag.pinchZoom | InteractiveFlag.doubleTapZoom;
 
-  StreamSubscription<MapEvent> subscription;
+  late StreamSubscription<MapEvent> subscription;
 
   @override
   void initState() {
@@ -159,7 +159,7 @@ class _InteractiveTestPageState extends State<InteractiveTestPage> {
                     }
 
                     return Text(
-                      'Current event: ${snapshot.data.runtimeType}\nSource: ${snapshot.data.source}',
+                      'Current event: ${snapshot.data.runtimeType}\nSource: ${snapshot.data!.source}',
                       textAlign: TextAlign.center,
                     );
                   },
diff --git a/example/lib/pages/live_location.dart b/example/lib/pages/live_location.dart
index 707208aa6..1566131d1 100644
--- a/example/lib/pages/live_location.dart
+++ b/example/lib/pages/live_location.dart
@@ -1,7 +1,7 @@
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 import 'package:location/location.dart';
 
 import '../widgets/drawer.dart';
@@ -14,13 +14,13 @@ class LiveLocationPage extends StatefulWidget {
 }
 
 class _LiveLocationPageState extends State<LiveLocationPage> {
-  LocationData _currentLocation;
-  MapController _mapController;
+  LocationData? _currentLocation;
+  late MapController _mapController;
 
   bool _liveUpdate = false;
   bool _permission = false;
 
-  String _serviceError = '';
+  String? _serviceError = '';
 
   var interActiveFlags = InteractiveFlag.all;
 
@@ -35,11 +35,11 @@ class _LiveLocationPageState extends State<LiveLocationPage> {
 
   void initLocationService() async {
     await _locationService.changeSettings(
-      accuracy: LocationAccuracy.HIGH,
+      accuracy: LocationAccuracy.high,
       interval: 1000,
     );
 
-    LocationData location;
+    LocationData? location;
     bool serviceEnabled;
     bool serviceRequestResult;
 
@@ -48,13 +48,12 @@ class _LiveLocationPageState extends State<LiveLocationPage> {
 
       if (serviceEnabled) {
         var permission = await _locationService.requestPermission();
-        _permission = permission == PermissionStatus.GRANTED;
+        _permission = permission == PermissionStatus.granted;
 
         if (_permission) {
           location = await _locationService.getLocation();
           _currentLocation = location;
-          _locationService
-              .onLocationChanged()
+          _locationService.onLocationChanged
               .listen((LocationData result) async {
             if (mounted) {
               setState(() {
@@ -63,8 +62,8 @@ class _LiveLocationPageState extends State<LiveLocationPage> {
                 // If Live Update is enabled, move map center
                 if (_liveUpdate) {
                   _mapController.move(
-                      LatLng(_currentLocation.latitude,
-                          _currentLocation.longitude),
+                      LatLng(_currentLocation!.latitude!,
+                          _currentLocation!.longitude!),
                       _mapController.zoom);
                 }
               });
@@ -97,7 +96,7 @@ class _LiveLocationPageState extends State<LiveLocationPage> {
     // by default or store previous location value to show.
     if (_currentLocation != null) {
       currentLatLng =
-          LatLng(_currentLocation.latitude, _currentLocation.longitude);
+          LatLng(_currentLocation!.latitude!, _currentLocation!.longitude!);
     } else {
       currentLatLng = LatLng(0, 0);
     }
@@ -125,7 +124,7 @@ class _LiveLocationPageState extends State<LiveLocationPage> {
           children: [
             Padding(
               padding: EdgeInsets.only(top: 8.0, bottom: 8.0),
-              child: _serviceError.isEmpty
+              child: _serviceError!.isEmpty
                   ? Text('This is a map that is showing '
                       '(${currentLatLng.latitude}, ${currentLatLng.longitude}).')
                   : Text(
diff --git a/example/lib/pages/map_controller.dart b/example/lib/pages/map_controller.dart
index b21f360c3..433084247 100644
--- a/example/lib/pages/map_controller.dart
+++ b/example/lib/pages/map_controller.dart
@@ -2,7 +2,7 @@ import 'dart:async';
 
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 import 'package:location/location.dart';
 
 import '../widgets/drawer.dart';
@@ -21,7 +21,7 @@ class MapControllerPageState extends State<MapControllerPage> {
   static LatLng paris = LatLng(48.8566, 2.3522);
   static LatLng dublin = LatLng(53.3498, -6.2603);
 
-  MapController mapController;
+  late MapController mapController;
   double rotation = 0.0;
 
   @override
@@ -119,7 +119,7 @@ class MapControllerPageState extends State<MapControllerPage> {
                   Builder(builder: (BuildContext context) {
                     return MaterialButton(
                       onPressed: () {
-                        final bounds = mapController.bounds;
+                        final bounds = mapController.bounds!;
 
                         ScaffoldMessenger.of(context).showSnackBar(SnackBar(
                           content: Text(
@@ -178,8 +178,8 @@ class MapControllerPageState extends State<MapControllerPage> {
 
 class CurrentLocation extends StatefulWidget {
   const CurrentLocation({
-    Key key,
-    @required this.mapController,
+    Key? key,
+    required this.mapController,
   }) : super(key: key);
 
   final MapController mapController;
@@ -192,7 +192,7 @@ class _CurrentLocationState extends State<CurrentLocation> {
   int _eventKey = 0;
 
   var icon = Icons.gps_not_fixed;
-  StreamSubscription<MapEvent> mapEventSubscription;
+  late StreamSubscription<MapEvent> mapEventSubscription;
 
   @override
   void initState() {
@@ -229,7 +229,7 @@ class _CurrentLocationState extends State<CurrentLocation> {
     try {
       var currentLocation = await location.getLocation();
       var moved = widget.mapController.move(
-        LatLng(currentLocation.latitude, currentLocation.longitude),
+        LatLng(currentLocation.latitude!, currentLocation.longitude!),
         18,
         id: _eventKey.toString(),
       );
diff --git a/example/lib/pages/marker_anchor.dart b/example/lib/pages/marker_anchor.dart
index 522abf71a..8f5c4e482 100644
--- a/example/lib/pages/marker_anchor.dart
+++ b/example/lib/pages/marker_anchor.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
@@ -13,7 +13,7 @@ class MarkerAnchorPage extends StatefulWidget {
 }
 
 class MarkerAnchorPageState extends State<MarkerAnchorPage> {
-  AnchorPos anchorPos;
+  late AnchorPos anchorPos;
 
   @override
   void initState() {
diff --git a/example/lib/pages/moving_markers.dart b/example/lib/pages/moving_markers.dart
index 8719d4e65..f92046bf3 100644
--- a/example/lib/pages/moving_markers.dart
+++ b/example/lib/pages/moving_markers.dart
@@ -2,7 +2,7 @@ import 'dart:async';
 
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
@@ -16,8 +16,8 @@ class MovingMarkersPage extends StatefulWidget {
 }
 
 class _MovingMarkersPageState extends State<MovingMarkersPage> {
-  Marker _marker;
-  Timer _timer;
+  Marker? _marker;
+  late Timer _timer;
   int _markerIndex = 0;
 
   @override
@@ -62,7 +62,7 @@ class _MovingMarkersPageState extends State<MovingMarkersPage> {
                       urlTemplate:
                           'https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png',
                       subdomains: ['a', 'b', 'c']),
-                  MarkerLayerOptions(markers: <Marker>[_marker])
+                  MarkerLayerOptions(markers: [_marker!])
                 ],
               ),
             ),
diff --git a/example/lib/pages/offline_map.dart b/example/lib/pages/offline_map.dart
index c2e75a496..868bde97d 100644
--- a/example/lib/pages/offline_map.dart
+++ b/example/lib/pages/offline_map.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/on_tap.dart b/example/lib/pages/on_tap.dart
index 557a7b7a7..8aba3db83 100644
--- a/example/lib/pages/on_tap.dart
+++ b/example/lib/pages/on_tap.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/overlay_image.dart b/example/lib/pages/overlay_image.dart
index 38ce7615d..79816db2b 100644
--- a/example/lib/pages/overlay_image.dart
+++ b/example/lib/pages/overlay_image.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/plugin_api.dart b/example/lib/pages/plugin_api.dart
index 50af71834..7c87fe600 100644
--- a/example/lib/pages/plugin_api.dart
+++ b/example/lib/pages/plugin_api.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/plugin_api.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
@@ -46,9 +46,9 @@ class PluginPage extends StatelessWidget {
 class MyCustomPluginOptions extends LayerOptions {
   final String text;
   MyCustomPluginOptions({
-    Key key,
+    Key? key,
     this.text = '',
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
   }) : super(key: key, rebuild: rebuild);
 }
 
diff --git a/example/lib/pages/plugin_scalebar.dart b/example/lib/pages/plugin_scalebar.dart
index cfcb8c2e6..2780456b6 100644
--- a/example/lib/pages/plugin_scalebar.dart
+++ b/example/lib/pages/plugin_scalebar.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/plugin_api.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 import 'scale_layer_plugin_option.dart';
diff --git a/example/lib/pages/plugin_zoombuttons.dart b/example/lib/pages/plugin_zoombuttons.dart
index e48886668..e2b24686b 100644
--- a/example/lib/pages/plugin_zoombuttons.dart
+++ b/example/lib/pages/plugin_zoombuttons.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/plugin_api.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 import 'zoombuttons_plugin_option.dart';
diff --git a/example/lib/pages/polyline.dart b/example/lib/pages/polyline.dart
index 8fd1ee355..5d17a336b 100644
--- a/example/lib/pages/polyline.dart
+++ b/example/lib/pages/polyline.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/scale_layer_plugin_option.dart b/example/lib/pages/scale_layer_plugin_option.dart
index 14bdf1201..99e83025f 100644
--- a/example/lib/pages/scale_layer_plugin_option.dart
+++ b/example/lib/pages/scale_layer_plugin_option.dart
@@ -8,18 +8,18 @@ import 'package:flutter_map/plugin_api.dart';
 import './scalebar_utils.dart' as util;
 
 class ScaleLayerPluginOption extends LayerOptions {
-  TextStyle textStyle;
+  TextStyle? textStyle;
   Color lineColor;
   double lineWidth;
-  final EdgeInsets padding;
+  final EdgeInsets? padding;
 
   ScaleLayerPluginOption({
-    Key key,
+    Key? key,
     this.textStyle,
     this.lineColor = Colors.white,
     this.lineWidth = 2,
     this.padding,
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
   }) : super(key: key, rebuild: rebuild);
 }
 
@@ -84,7 +84,7 @@ class ScaleLayer extends StatelessWidget {
     var displayDistance = distance > 999
         ? '${(distance / 1000).toStringAsFixed(0)} km'
         : '${distance.toStringAsFixed(0)} m';
-    double width = (end.x - start.x);
+    var width = (end.x - (start.x as double));
 
     return CustomPaint(
       painter: ScalePainter(
@@ -103,36 +103,38 @@ class ScalePainter extends CustomPainter {
   ScalePainter(this.width, this.text,
       {this.padding, this.textStyle, this.lineWidth, this.lineColor});
   final double width;
-  final EdgeInsets padding;
+  final EdgeInsets? padding;
   final String text;
-  TextStyle textStyle;
-  double lineWidth;
-  Color lineColor;
+  TextStyle? textStyle;
+  double? lineWidth;
+  Color? lineColor;
 
   @override
   void paint(ui.Canvas canvas, ui.Size size) {
     final paint = Paint()
-      ..color = lineColor
+      ..color = lineColor!
       ..strokeCap = StrokeCap.square
-      ..strokeWidth = lineWidth;
+      ..strokeWidth = lineWidth!;
 
     var sizeForStartEnd = 4;
-    var paddingLeft = padding == null ? 0 : padding.left + sizeForStartEnd / 2;
-    var paddingTop = padding == null ? 0 : padding.top;
+    var paddingLeft = padding == null ? 0 : padding!.left + sizeForStartEnd / 2;
+    var paddingTop = padding == null ? 0 : padding!.top;
 
     var textSpan = TextSpan(style: textStyle, text: text);
     var textPainter =
         TextPainter(text: textSpan, textDirection: TextDirection.ltr)..layout();
-    textPainter.paint(canvas,
-        Offset(width / 2 - textPainter.width / 2 + paddingLeft, paddingTop));
+    textPainter.paint(
+        canvas,
+        Offset(width / 2 - textPainter.width / 2 + paddingLeft,
+            paddingTop as double));
     paddingTop += textPainter.height;
-    var p1 = Offset(paddingLeft, sizeForStartEnd + paddingTop);
+    var p1 = Offset(paddingLeft as double, sizeForStartEnd + paddingTop);
     var p2 = Offset(paddingLeft + width, sizeForStartEnd + paddingTop);
     // draw start line
     canvas.drawLine(Offset(paddingLeft, paddingTop),
         Offset(paddingLeft, sizeForStartEnd + paddingTop), paint);
     // draw middle line
-    var middleX = width / 2 + paddingLeft - lineWidth / 2;
+    var middleX = width / 2 + paddingLeft - lineWidth! / 2;
     canvas.drawLine(Offset(middleX, paddingTop + sizeForStartEnd / 2),
         Offset(middleX, sizeForStartEnd + paddingTop), paint);
     // draw end line
diff --git a/example/lib/pages/scalebar_utils.dart b/example/lib/pages/scalebar_utils.dart
index 1f7b232e8..f888e2e8d 100644
--- a/example/lib/pages/scalebar_utils.dart
+++ b/example/lib/pages/scalebar_utils.dart
@@ -1,7 +1,8 @@
 import 'dart:math';
-import 'package:latlong/latlong.dart';
 
-const double piOver180 = PI / 180.0;
+import 'package:latlong2/latlong.dart';
+
+const double piOver180 = pi / 180.0;
 double toDegrees(double radians) {
   return radians / piOver180;
 }
diff --git a/example/lib/pages/sliding_map.dart b/example/lib/pages/sliding_map.dart
index 249578dd3..d9286803c 100644
--- a/example/lib/pages/sliding_map.dart
+++ b/example/lib/pages/sliding_map.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/tap_to_add.dart b/example/lib/pages/tap_to_add.dart
index 81ec190b0..0cfbdd0ac 100644
--- a/example/lib/pages/tap_to_add.dart
+++ b/example/lib/pages/tap_to_add.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/tile_builder_example.dart b/example/lib/pages/tile_builder_example.dart
index 2dc974440..bdf5f5b55 100644
--- a/example/lib/pages/tile_builder_example.dart
+++ b/example/lib/pages/tile_builder_example.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
@@ -43,7 +43,7 @@ class _TileBuilderPageState extends State<TileBuilderPage> {
                     tile.loaded == null
                         ? 'Loading'
                         // sometimes result is negative which shouldn't happen, abs() corrects it
-                        : '${(tile.loaded.millisecond - tile.loadStarted.millisecond).abs()} ms',
+                        : '${(tile.loaded!.millisecond - tile.loadStarted.millisecond).abs()} ms',
                     style: Theme.of(context).textTheme.headline5,
                   ),
               ],
diff --git a/example/lib/pages/tile_loading_error_handle.dart b/example/lib/pages/tile_loading_error_handle.dart
index 85d39ad39..03c2392c0 100644
--- a/example/lib/pages/tile_loading_error_handle.dart
+++ b/example/lib/pages/tile_loading_error_handle.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
@@ -48,7 +48,7 @@ class _TileLoadingErrorHandleState extends State<TileLoadingErrorHandle> {
                       tileProvider: NonCachingNetworkTileProvider(),
                       errorTileCallback: (Tile tile, error) {
                         if (_needLoadingError) {
-                          WidgetsBinding.instance.addPostFrameCallback((_) {
+                          WidgetsBinding.instance!.addPostFrameCallback((_) {
                             ScaffoldMessenger.of(context).showSnackBar(SnackBar(
                               duration: Duration(seconds: 1),
                               content: Text(
diff --git a/example/lib/pages/widgets.dart b/example/lib/pages/widgets.dart
index a72d7f23f..458a26a10 100644
--- a/example/lib/pages/widgets.dart
+++ b/example/lib/pages/widgets.dart
@@ -2,7 +2,7 @@ import 'dart:async';
 
 import 'package:flutter/material.dart';
 import 'package:flutter_map/plugin_api.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../pages/zoombuttons_plugin_option.dart';
 import '../widgets/drawer.dart';
@@ -74,8 +74,8 @@ class MovingWithoutRefreshAllMapMarkers extends StatefulWidget {
 
 class _MovingWithoutRefreshAllMapMarkersState
     extends State<MovingWithoutRefreshAllMapMarkers> {
-  Marker _marker;
-  Timer _timer;
+  Marker? _marker;
+  Timer? _timer;
   int _markerIndex = 0;
 
   @override
@@ -99,7 +99,7 @@ class _MovingWithoutRefreshAllMapMarkersState
   @override
   Widget build(BuildContext context) {
     return MarkerLayerWidget(
-      options: MarkerLayerOptions(markers: <Marker>[_marker]),
+      options: MarkerLayerOptions(markers: [_marker!]),
     );
   }
 }
diff --git a/example/lib/pages/wms_tile_layer.dart b/example/lib/pages/wms_tile_layer.dart
index 70bf91130..480103f7e 100644
--- a/example/lib/pages/wms_tile_layer.dart
+++ b/example/lib/pages/wms_tile_layer.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 import '../widgets/drawer.dart';
 
diff --git a/example/lib/pages/zoombuttons_plugin_option.dart b/example/lib/pages/zoombuttons_plugin_option.dart
index 9f27b7021..944324ce6 100644
--- a/example/lib/pages/zoombuttons_plugin_option.dart
+++ b/example/lib/pages/zoombuttons_plugin_option.dart
@@ -8,15 +8,15 @@ class ZoomButtonsPluginOption extends LayerOptions {
   final bool mini;
   final double padding;
   final Alignment alignment;
-  final Color zoomInColor;
-  final Color zoomInColorIcon;
-  final Color zoomOutColor;
-  final Color zoomOutColorIcon;
+  final Color? zoomInColor;
+  final Color? zoomInColorIcon;
+  final Color? zoomOutColor;
+  final Color? zoomOutColorIcon;
   final IconData zoomInIcon;
   final IconData zoomOutIcon;
 
   ZoomButtonsPluginOption({
-    Key key,
+    Key? key,
     this.minZoom = 1,
     this.maxZoom = 18,
     this.mini = true,
@@ -28,7 +28,7 @@ class ZoomButtonsPluginOption extends LayerOptions {
     this.zoomOutColor,
     this.zoomOutColorIcon,
     this.zoomOutIcon = Icons.zoom_out,
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
   }) : super(key: key, rebuild: rebuild);
 }
 
@@ -76,13 +76,14 @@ class ZoomButtons extends StatelessWidget {
               backgroundColor:
                   zoomButtonsOpts.zoomInColor ?? Theme.of(context).primaryColor,
               onPressed: () {
-                var bounds = map.getBounds();
+                var bounds = map.getBounds()!;
                 var centerZoom = map.getBoundsCenterZoom(bounds, options);
                 var zoom = centerZoom.zoom + 1;
                 if (zoom < zoomButtonsOpts.minZoom) {
                   zoom = zoomButtonsOpts.minZoom as double;
                 } else {
-                  map.move(centerZoom.center, zoom);
+                  map.move(centerZoom.center, zoom,
+                      source: MapEventSource.custom);
                 }
               },
               child: Icon(zoomButtonsOpts.zoomInIcon,
@@ -98,13 +99,14 @@ class ZoomButtons extends StatelessWidget {
               backgroundColor: zoomButtonsOpts.zoomOutColor ??
                   Theme.of(context).primaryColor,
               onPressed: () {
-                var bounds = map.getBounds();
+                var bounds = map.getBounds()!;
                 var centerZoom = map.getBoundsCenterZoom(bounds, options);
                 var zoom = centerZoom.zoom - 1;
                 if (zoom > zoomButtonsOpts.maxZoom) {
                   zoom = zoomButtonsOpts.maxZoom as double;
                 } else {
-                  map.move(centerZoom.center, zoom);
+                  map.move(centerZoom.center, zoom,
+                      source: MapEventSource.custom);
                 }
               },
               child: Icon(zoomButtonsOpts.zoomOutIcon,
diff --git a/example/lib/test_app.dart b/example/lib/test_app.dart
index 86a0a2456..830cb98b9 100644
--- a/example/lib/test_app.dart
+++ b/example/lib/test_app.dart
@@ -1,6 +1,6 @@
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 void main() {
   runApp(TestApp());
diff --git a/example/pubspec.yaml b/example/pubspec.yaml
index 1589dd712..1f6fcc7db 100644
--- a/example/pubspec.yaml
+++ b/example/pubspec.yaml
@@ -18,7 +18,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 version: 1.0.0+1
 
 environment:
-  sdk: ">=2.7.0 <3.0.0"
+  sdk: '>=2.12.0 <3.0.0'
 
 dependencies:
   flutter:
@@ -28,7 +28,7 @@ dependencies:
   cupertino_icons: ^1.0.2
   flutter_map:
     path: ../
-  location: ^2.5.0
+  location: ^4.1.1
 
 dev_dependencies:
   pedantic: ^1.11.0
diff --git a/flutter_map.iml b/flutter_map.iml
index 6048a33bd..e9a86d25d 100644
--- a/flutter_map.iml
+++ b/flutter_map.iml
@@ -16,4 +16,4 @@
     <orderEntry type="library" name="Dart SDK" level="project" />
     <orderEntry type="library" name="Flutter Plugins" level="project" />
   </component>
-</module>
\ No newline at end of file
+</module>
diff --git a/lib/flutter_map.dart b/lib/flutter_map.dart
index d6bf937e0..4679b5ac1 100644
--- a/lib/flutter_map.dart
+++ b/lib/flutter_map.dart
@@ -12,7 +12,7 @@ import 'package:flutter_map/src/gestures/multi_finger_gesture.dart';
 import 'package:flutter_map/src/map/flutter_map_state.dart';
 import 'package:flutter_map/src/map/map.dart';
 import 'package:flutter_map/src/plugins/plugin.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 export 'package:flutter_map/src/core/point.dart';
 export 'package:flutter_map/src/geo/crs/crs.dart';
@@ -66,18 +66,17 @@ class FlutterMap extends StatefulWidget {
   final MapOptions options;
 
   /// A [MapController], used to control the map.
-  final MapControllerImpl _mapController;
+  final MapControllerImpl? _mapController;
 
   FlutterMap({
-    Key key,
-    @required this.options,
+    Key? key,
+    required this.options,
     this.layers = const [],
     this.nonRotatedLayers = const [],
     this.children = const [],
     this.nonRotatedChildren = const [],
-    MapController mapController,
-  })  : assert(options != null, 'MapOptions cannot be null!'),
-        _mapController = mapController,
+    MapController? mapController,
+  })  : _mapController = mapController as MapControllerImpl?,
         super(key: key);
 
   @override
@@ -101,7 +100,7 @@ abstract class MapController {
   /// returns `true` if move was success (for example it won't be success if
   /// navigating to same place with same zoom or if center is out of bounds and
   /// [MapOptions.slideOnBoundaries] isn't enabled)
-  bool move(LatLng center, double zoom, {String id});
+  bool move(LatLng center, double zoom, {String? id});
 
   /// Sets the map rotation to a certain degrees angle (in decimal).
   ///
@@ -112,16 +111,16 @@ abstract class MapController {
   ///
   /// returns `true` if rotate was success (it won't be success if rotate is
   /// same as the old rotate)
-  bool rotate(double degree, {String id});
+  bool rotate(double degree, {String? id});
 
   /// Calls [move] and [rotate] together however layers will rebuild just once
   /// instead of twice
   MoveAndRotateResult moveAndRotate(LatLng center, double zoom, double degree,
-      {String id});
+      {String? id});
 
   /// Fits the map bounds. Optional constraints can be defined
   /// through the [options] parameter.
-  void fitBounds(LatLngBounds bounds, {FitBoundsOptions options});
+  void fitBounds(LatLngBounds bounds, {FitBoundsOptions? options});
 
   bool get ready;
 
@@ -129,7 +128,7 @@ abstract class MapController {
 
   LatLng get center;
 
-  LatLngBounds get bounds;
+  LatLngBounds? get bounds;
 
   double get zoom;
 
@@ -219,38 +218,38 @@ class MapOptions {
   /// gestures will take effect see [MultiFingerGesture] for custom settings
   final int pinchMoveWinGestures;
 
-  final double minZoom;
-  final double maxZoom;
+  final double? minZoom;
+  final double? maxZoom;
   @deprecated
   final bool debug; // TODO no usage outside of constructor. Marked for removal?
   @Deprecated('use interactiveFlags instead')
-  final bool interactive;
+  final bool? interactive;
 
   /// see [InteractiveFlag] for custom settings
   final int interactiveFlags;
 
   final bool allowPanning;
 
-  final TapCallback onTap;
-  final LongPressCallback onLongPress;
-  final PositionCallback onPositionChanged;
+  final TapCallback? onTap;
+  final LongPressCallback? onLongPress;
+  final PositionCallback? onPositionChanged;
   final List<MapPlugin> plugins;
   final bool slideOnBoundaries;
-  final Size screenSize;
+  final Size? screenSize;
   final bool adaptiveBoundaries;
-  final MapController controller;
+  final MapController? controller;
   final LatLng center;
-  final LatLngBounds bounds;
+  final LatLngBounds? bounds;
   final FitBoundsOptions boundsOptions;
-  final LatLng swPanBoundary;
-  final LatLng nePanBoundary;
+  final LatLng? swPanBoundary;
+  final LatLng? nePanBoundary;
 
-  _SafeArea _safeAreaCache;
-  double _safeAreaZoom;
+  _SafeArea? _safeAreaCache;
+  double? _safeAreaZoom;
 
   MapOptions({
     this.crs = const Epsg3857(),
-    LatLng center,
+    LatLng? center,
     this.bounds,
     this.boundsOptions = const FitBoundsOptions(),
     this.zoom = 13.0,
@@ -272,7 +271,7 @@ class MapOptions {
     // TODO: Change when [interactive] is removed.
     // Change this to [this.interactiveFlags = InteractiveFlag.all] and remove
     // [interactiveFlags] from initializer list
-    int interactiveFlags,
+    int? interactiveFlags,
     this.allowPanning = true,
     this.onTap,
     this.onLongPress,
@@ -300,18 +299,18 @@ class MapOptions {
   }
 
   //if there is a pan boundary, do not cross
-  bool isOutOfBounds(LatLng center) {
+  bool isOutOfBounds(LatLng? center) {
     if (adaptiveBoundaries) {
-      return !_safeArea.contains(center);
+      return !_safeArea!.contains(center);
     }
     if (swPanBoundary != null && nePanBoundary != null) {
       if (center == null) {
         return true;
-      } else if (center.latitude < swPanBoundary.latitude ||
-          center.latitude > nePanBoundary.latitude) {
+      } else if (center.latitude < swPanBoundary!.latitude ||
+          center.latitude > nePanBoundary!.latitude) {
         return true;
-      } else if (center.longitude < swPanBoundary.longitude ||
-          center.longitude > nePanBoundary.longitude) {
+      } else if (center.longitude < swPanBoundary!.longitude ||
+          center.longitude > nePanBoundary!.longitude) {
         return true;
       }
     }
@@ -320,25 +319,26 @@ class MapOptions {
 
   LatLng containPoint(LatLng point, LatLng fallback) {
     if (adaptiveBoundaries) {
-      return _safeArea.containPoint(point, fallback);
+      return _safeArea!.containPoint(point, fallback);
     } else {
       return LatLng(
-        point.latitude.clamp(swPanBoundary.latitude, nePanBoundary.latitude),
-        point.longitude.clamp(swPanBoundary.longitude, nePanBoundary.longitude),
+        point.latitude.clamp(swPanBoundary!.latitude, nePanBoundary!.latitude),
+        point.longitude
+            .clamp(swPanBoundary!.longitude, nePanBoundary!.longitude),
       );
     }
   }
 
-  _SafeArea get _safeArea {
+  _SafeArea? get _safeArea {
     final controllerZoom = _getControllerZoom();
     if (controllerZoom != _safeAreaZoom || _safeAreaCache == null) {
       _safeAreaZoom = controllerZoom;
       final halfScreenHeight = _calculateScreenHeightInDegrees() / 2;
       final halfScreenWidth = _calculateScreenWidthInDegrees() / 2;
-      final southWestLatitude = swPanBoundary.latitude + halfScreenHeight;
-      final southWestLongitude = swPanBoundary.longitude + halfScreenWidth;
-      final northEastLatitude = nePanBoundary.latitude - halfScreenHeight;
-      final northEastLongitude = nePanBoundary.longitude - halfScreenWidth;
+      final southWestLatitude = swPanBoundary!.latitude + halfScreenHeight;
+      final southWestLongitude = swPanBoundary!.longitude + halfScreenWidth;
+      final northEastLatitude = nePanBoundary!.latitude - halfScreenHeight;
+      final northEastLongitude = nePanBoundary!.longitude - halfScreenWidth;
       _safeAreaCache = _SafeArea(
         LatLng(
           southWestLatitude,
@@ -356,19 +356,19 @@ class MapOptions {
   double _calculateScreenWidthInDegrees() {
     final zoom = _getControllerZoom();
     final degreesPerPixel = 360 / pow(2, zoom + 8);
-    return screenSize.width * degreesPerPixel;
+    return screenSize!.width * degreesPerPixel;
   }
 
   double _calculateScreenHeightInDegrees() =>
-      screenSize.height * 170.102258 / pow(2, _getControllerZoom() + 8);
+      screenSize!.height * 170.102258 / pow(2, _getControllerZoom() + 8);
 
-  double _getControllerZoom() => controller.ready ? controller.zoom : zoom;
+  double _getControllerZoom() => controller!.ready ? controller!.zoom : zoom;
 }
 
 class FitBoundsOptions {
   final EdgeInsets padding;
   final double maxZoom;
-  final double zoom;
+  final double? zoom;
 
   const FitBoundsOptions({
     this.padding = const EdgeInsets.all(0.0),
@@ -379,9 +379,9 @@ class FitBoundsOptions {
 
 /// Position's type for [PositionCallback].
 class MapPosition {
-  final LatLng center;
-  final LatLngBounds bounds;
-  final double zoom;
+  final LatLng? center;
+  final LatLngBounds? bounds;
+  final double? zoom;
   final bool hasGesture;
 
   MapPosition({this.center, this.bounds, this.zoom, this.hasGesture = false});
diff --git a/lib/src/core/bounds.dart b/lib/src/core/bounds.dart
index 5111ac3d7..4801b1b8f 100644
--- a/lib/src/core/bounds.dart
+++ b/lib/src/core/bounds.dart
@@ -1,4 +1,5 @@
 import 'dart:math' as math;
+
 import 'package:flutter_map/src/core/point.dart';
 
 /// Rectangular bound delimited by orthogonal lines passing through two
@@ -18,20 +19,16 @@ class Bounds<T extends num> {
   /// Creates a new [Bounds] obtained by expanding the current ones with a new
   /// point.
   Bounds<T> extend(CustomPoint<T> point) {
-    CustomPoint<T> newMin;
-    CustomPoint<T> newMax;
-    if (min == null && max == null) {
-      newMin = point;
-      newMax = point;
-    } else {
-      var minX = math.min(point.x, min.x);
-      var maxX = math.max(point.x, max.x);
-      var minY = math.min(point.y, min.y);
-      var maxY = math.max(point.y, max.y);
-      newMin = CustomPoint(minX, minY);
-      newMax = CustomPoint(maxX, maxY);
-    }
-    return Bounds._(newMin, newMax);
+    return Bounds._(
+      CustomPoint(
+        math.min(point.x, min.x),
+        math.min(point.y, min.y),
+      ),
+      CustomPoint(
+        math.max(point.x, max.x),
+        math.max(point.y, max.y),
+      ),
+    );
   }
 
   /// This [Bounds] cental point.
diff --git a/lib/src/core/center_zoom.dart b/lib/src/core/center_zoom.dart
index a725d6fe8..527768d47 100644
--- a/lib/src/core/center_zoom.dart
+++ b/lib/src/core/center_zoom.dart
@@ -1,7 +1,7 @@
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 class CenterZoom {
   final LatLng center;
   final double zoom;
-  CenterZoom({this.center, this.zoom});
+  CenterZoom({required this.center, required this.zoom});
 }
diff --git a/lib/src/core/point.dart b/lib/src/core/point.dart
index de28370b1..19b6cef0e 100644
--- a/lib/src/core/point.dart
+++ b/lib/src/core/point.dart
@@ -1,7 +1,7 @@
 import 'dart:math' as math;
 
 class CustomPoint<T extends num> extends math.Point<T> {
-  const CustomPoint(num x, num y) : super(x, y);
+  const CustomPoint(num x, num y) : super(x as T, y as T);
 
   CustomPoint<T> operator /(num /*T|int*/ factor) {
     return CustomPoint<T>(x / factor, y / factor);
@@ -39,8 +39,8 @@ class CustomPoint<T extends num> extends math.Point<T> {
   }
 
   CustomPoint round() {
-    var x = this.x is double ? this.x.round() : this.x;
-    var y = this.y is double ? this.y.round() : this.y;
+    final x = this.x is double ? this.x.round() : this.x;
+    final y = this.y is double ? this.y.round() : this.y;
     return CustomPoint(x, y);
   }
 
diff --git a/lib/src/core/util.dart b/lib/src/core/util.dart
index 004a281b7..c670a459c 100644
--- a/lib/src/core/util.dart
+++ b/lib/src/core/util.dart
@@ -9,7 +9,7 @@ var _templateRe = RegExp(r'\{ *([\w_-]+) *\}');
 /// Throws an [Exception] if any placeholder remains unresolved.
 String template(String str, Map<String, String> data) {
   return str.replaceAllMapped(_templateRe, (Match match) {
-    var value = data[match.group(1)];
+    var value = data[match.group(1)!];
     if (value == null) {
       throw Exception('No value provided for variable ${match.group(1)}');
     } else {
@@ -18,7 +18,7 @@ String template(String str, Map<String, String> data) {
   });
 }
 
-double wrapNum(double x, Tuple2<double, double> range, [bool includeMax]) {
+double wrapNum(double x, Tuple2<double, double> range, [bool? includeMax]) {
   var max = range.item2;
   var min = range.item1;
   var d = max - min;
@@ -26,18 +26,18 @@ double wrapNum(double x, Tuple2<double, double> range, [bool includeMax]) {
 }
 
 StreamTransformer<T, T> throttleStreamTransformerWithTrailingCall<T>(
-    Duration duration) {
-  Timer timer;
+    Duration? duration) {
+  Timer? timer;
   T recentData;
   var trailingCall = false;
 
-  void Function(T data, EventSink<T> sink) throttleHandler;
+  late void Function(T data, EventSink<T> sink) throttleHandler;
   throttleHandler = (T data, EventSink<T> sink) {
     recentData = data;
 
     if (timer == null) {
       sink.add(recentData);
-      timer = Timer(duration, () {
+      timer = Timer(duration!, () {
         timer = null;
 
         if (trailingCall) {
diff --git a/lib/src/geo/crs/crs.dart b/lib/src/geo/crs/crs.dart
index 024f779e4..fad20c1be 100644
--- a/lib/src/geo/crs/crs.dart
+++ b/lib/src/geo/crs/crs.dart
@@ -2,7 +2,7 @@ import 'dart:math' as math;
 
 import 'package:flutter_map/src/core/bounds.dart';
 import 'package:flutter_map/src/core/point.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 import 'package:meta/meta.dart';
 import 'package:proj4dart/proj4dart.dart' as proj4;
 import 'package:tuple/tuple.dart';
@@ -34,7 +34,7 @@ abstract class Crs {
   }
 
   /// Converts a map point to the sphere coordinate (at a certain zoom).
-  LatLng pointToLatLng(CustomPoint point, double zoom) {
+  LatLng? pointToLatLng(CustomPoint point, double zoom) {
     var scale = this.scale(zoom);
     var untransformedPoint =
         transformation.untransform(point, scale.toDouble());
@@ -56,10 +56,10 @@ abstract class Crs {
   }
 
   /// Rescales the bounds to a given zoom value.
-  Bounds getProjectedBounds(double zoom) {
+  Bounds? getProjectedBounds(double zoom) {
     if (infinite) return null;
 
-    var b = projection.bounds;
+    var b = projection.bounds!;
     var s = scale(zoom);
     var min = transformation.transform(b.min, s.toDouble());
     var max = transformation.transform(b.max, s.toDouble());
@@ -68,9 +68,9 @@ abstract class Crs {
 
   bool get infinite;
 
-  Tuple2<double, double> get wrapLng;
+  Tuple2<double, double>? get wrapLng;
 
-  Tuple2<double, double> get wrapLat;
+  Tuple2<double, double>? get wrapLat;
 }
 
 // Custom CRS for non geographical maps
@@ -93,10 +93,10 @@ class CrsSimple extends Crs {
   bool get infinite => false;
 
   @override
-  Tuple2<double, double> get wrapLat => null;
+  Tuple2<double, double>? get wrapLat => null;
 
   @override
-  Tuple2<double, double> get wrapLng => null;
+  Tuple2<double, double>? get wrapLng => null;
 }
 
 abstract class Earth extends Crs {
@@ -107,7 +107,7 @@ abstract class Earth extends Crs {
   final Tuple2<double, double> wrapLng = const Tuple2(-180.0, 180.0);
 
   @override
-  final Tuple2<double, double> wrapLat = null;
+  final Tuple2<double, double>? wrapLat = null;
 
   const Earth() : super();
 }
@@ -167,42 +167,37 @@ class Proj4Crs extends Crs {
   final bool infinite;
 
   @override
-  final Tuple2<double, double> wrapLat = null;
+  final Tuple2<double, double>? wrapLat = null;
 
   @override
-  final Tuple2<double, double> wrapLng = null;
+  final Tuple2<double, double>? wrapLng = null;
 
-  final List<Transformation> _transformations;
+  final List<Transformation>? _transformations;
 
   final List<double> _scales;
 
   Proj4Crs._({
-    @required this.code,
-    @required this.projection,
-    @required this.transformation,
-    @required this.infinite,
-    @required List<Transformation> transformations,
-    @required List<double> scales,
-  })  : assert(null != code),
-        assert(null != projection),
-        assert(null != transformation || null != transformations),
-        assert(null != infinite),
-        assert(null != scales),
-        _transformations = transformations,
+    required this.code,
+    required this.projection,
+    required this.transformation,
+    required this.infinite,
+    List<Transformation>? transformations,
+    required List<double> scales,
+  })   : _transformations = transformations,
         _scales = scales;
 
   factory Proj4Crs.fromFactory({
-    @required String code,
-    @required proj4.Projection proj4Projection,
-    Transformation transformation,
-    List<CustomPoint> origins,
-    Bounds<double> bounds,
-    List<double> scales,
-    List<double> resolutions,
+    required String code,
+    required proj4.Projection proj4Projection,
+    Transformation? transformation,
+    List<CustomPoint>? origins,
+    Bounds<double>? bounds,
+    List<double>? scales,
+    List<double>? resolutions,
   }) {
     final projection =
         _Proj4Projection(proj4Projection: proj4Projection, bounds: bounds);
-    List<Transformation> transformations;
+    List<Transformation>? transformations;
     var infinite = null == bounds;
     List<double> finalScales;
 
@@ -231,7 +226,7 @@ class Proj4Crs extends Crs {
     return Proj4Crs._(
       code: code,
       projection: projection,
-      transformation: transformation,
+      transformation: transformation!,
       infinite: infinite,
       transformations: transformations,
       scales: finalScales,
@@ -255,7 +250,7 @@ class Proj4Crs extends Crs {
 
   /// Converts a map point to the sphere coordinate (at a certain zoom).
   @override
-  LatLng pointToLatLng(CustomPoint point, double zoom) {
+  LatLng? pointToLatLng(CustomPoint point, double zoom) {
     var scale = this.scale(zoom);
     var transformation = _getTransformationByZoom(zoom);
 
@@ -270,10 +265,10 @@ class Proj4Crs extends Crs {
 
   /// Rescales the bounds to a given zoom value.
   @override
-  Bounds getProjectedBounds(double zoom) {
+  Bounds? getProjectedBounds(double zoom) {
     if (infinite) return null;
 
-    var b = projection.bounds;
+    var b = projection.bounds!;
     var s = scale(zoom);
 
     var transformation = _getTransformationByZoom(zoom);
@@ -304,27 +299,25 @@ class Proj4Crs extends Crs {
   num zoom(double scale) {
     // Find closest number in _scales, down
     var downScale = _closestElement(_scales, scale);
+    if (downScale == null) {
+      return double.negativeInfinity;
+    }
     var downZoom = _scales.indexOf(downScale);
     // Check if scale is downScale => return array index
     if (scale == downScale) {
       return downZoom;
     }
-    if (downScale == null) {
-      return double.negativeInfinity;
-    }
     // Interpolate
     var nextZoom = downZoom + 1;
     var nextScale = _scales[nextZoom];
-    if (nextScale == null) {
-      return double.infinity;
-    }
+
     var scaleDiff = nextScale - downScale;
     return (scale - downScale) / scaleDiff + downZoom;
   }
 
   /// Get the closest lowest element in an array
-  double _closestElement(List<double> array, double element) {
-    double low;
+  double? _closestElement(List<double> array, double element) {
+    double? low;
     for (var i = array.length - 1; i >= 0; i--) {
       var curr = array[i];
 
@@ -342,24 +335,24 @@ class Proj4Crs extends Crs {
     }
 
     var iZoom = zoom.round();
-    var lastIdx = _transformations.length - 1;
+    var lastIdx = _transformations!.length - 1;
 
-    return _transformations[iZoom > lastIdx ? lastIdx : iZoom];
+    return _transformations![iZoom > lastIdx ? lastIdx : iZoom];
   }
 }
 
 abstract class Projection {
   const Projection();
 
-  Bounds<double> get bounds;
+  Bounds<double>? get bounds;
 
   CustomPoint project(LatLng latlng);
 
   LatLng unproject(CustomPoint point);
 
   double _inclusive(Comparable start, Comparable end, double value) {
-    if (value.compareTo(start) < 0) return start;
-    if (value.compareTo(end) > 0) return end;
+    if (value.compareTo(start as num) < 0) return start as double;
+    if (value.compareTo(end as num) > 0) return end as double;
 
     return value;
   }
@@ -391,7 +384,8 @@ class _LonLat extends Projection {
 
   @override
   LatLng unproject(CustomPoint point) {
-    return LatLng(inclusiveLat(point.y), inclusiveLng(point.x));
+    return LatLng(
+        inclusiveLat(point.y as double), inclusiveLng(point.x as double));
   }
 }
 
@@ -436,13 +430,12 @@ class _Proj4Projection extends Projection {
   final proj4.Projection proj4Projection;
 
   @override
-  final Bounds<double> bounds;
+  final Bounds<double>? bounds;
 
   _Proj4Projection({
-    @required this.proj4Projection,
-    @required this.bounds,
-  })  : assert(null != proj4Projection),
-        epsg4326 = proj4.Projection.WGS84;
+    required this.proj4Projection,
+    this.bounds,
+  }) : epsg4326 = proj4.Projection.WGS84;
 
   @override
   CustomPoint project(LatLng latlng) {
@@ -455,7 +448,7 @@ class _Proj4Projection extends Projection {
   @override
   LatLng unproject(CustomPoint point) {
     var point2 = proj4Projection.transform(
-        epsg4326, proj4.Point(x: point.x, y: point.y));
+        epsg4326, proj4.Point(x: point.x as double, y: point.y as double));
 
     return LatLng(inclusiveLat(point2.y), inclusiveLng(point2.x));
   }
@@ -469,14 +462,14 @@ class Transformation {
 
   const Transformation(this.a, this.b, this.c, this.d);
 
-  CustomPoint transform(CustomPoint<num> point, double scale) {
+  CustomPoint transform(CustomPoint<num> point, double? scale) {
     scale ??= 1.0;
     var x = scale * (a * point.x + b);
     var y = scale * (c * point.y + d);
     return CustomPoint(x, y);
   }
 
-  CustomPoint untransform(CustomPoint point, double scale) {
+  CustomPoint untransform(CustomPoint point, double? scale) {
     scale ??= 1.0;
     var x = (point.x / scale - b) / a;
     var y = (point.y / scale - d) / c;
diff --git a/lib/src/geo/latlng_bounds.dart b/lib/src/geo/latlng_bounds.dart
index 143366755..b27e8b324 100644
--- a/lib/src/geo/latlng_bounds.dart
+++ b/lib/src/geo/latlng_bounds.dart
@@ -1,21 +1,22 @@
 import 'dart:math' as math;
-import 'package:latlong/latlong.dart';
+
+import 'package:latlong2/latlong.dart';
 
 class LatLngBounds {
-  LatLng _sw;
-  LatLng _ne;
+  LatLng? _sw;
+  LatLng? _ne;
 
-  LatLngBounds([LatLng corner1, LatLng corner2]) {
+  LatLngBounds([LatLng? corner1, LatLng? corner2]) {
     extend(corner1);
     extend(corner2);
   }
 
   LatLngBounds.fromPoints(List<LatLng> points) {
-    if (points != null && points.isNotEmpty) {
-      num minX;
-      num maxX;
-      num minY;
-      num maxY;
+    if (points.isNotEmpty) {
+      num? minX;
+      num? maxX;
+      num? minY;
+      num? maxY;
 
       for (var point in points) {
         num x = point.longitudeInRad;
@@ -38,12 +39,12 @@ class LatLngBounds {
         }
       }
 
-      _sw = LatLng(radianToDeg(minY), radianToDeg(minX));
-      _ne = LatLng(radianToDeg(maxY), radianToDeg(maxX));
+      _sw = LatLng(radianToDeg(minY as double), radianToDeg(minX as double));
+      _ne = LatLng(radianToDeg(maxY as double), radianToDeg(maxX as double));
     }
   }
 
-  void extend(LatLng latlng) {
+  void extend(LatLng? latlng) {
     if (latlng == null) {
       return;
     }
@@ -54,25 +55,25 @@ class LatLngBounds {
     _extend(bounds._sw, bounds._ne);
   }
 
-  void _extend(LatLng sw2, LatLng ne2) {
+  void _extend(LatLng? sw2, LatLng? ne2) {
     if (_sw == null && _ne == null) {
-      _sw = LatLng(sw2.latitude, sw2.longitude);
-      _ne = LatLng(ne2.latitude, ne2.longitude);
+      _sw = LatLng(sw2!.latitude, sw2.longitude);
+      _ne = LatLng(ne2!.latitude, ne2.longitude);
     } else {
-      _sw.latitude = math.min(sw2.latitude, _sw.latitude);
-      _sw.longitude = math.min(sw2.longitude, _sw.longitude);
-      _ne.latitude = math.max(ne2.latitude, _ne.latitude);
-      _ne.longitude = math.max(ne2.longitude, _ne.longitude);
+      _sw!.latitude = math.min(sw2!.latitude, _sw!.latitude);
+      _sw!.longitude = math.min(sw2.longitude, _sw!.longitude);
+      _ne!.latitude = math.max(ne2!.latitude, _ne!.latitude);
+      _ne!.longitude = math.max(ne2.longitude, _ne!.longitude);
     }
   }
 
-  double get west => southWest.longitude;
-  double get south => southWest.latitude;
-  double get east => northEast.longitude;
-  double get north => northEast.latitude;
+  double get west => southWest!.longitude;
+  double get south => southWest!.latitude;
+  double get east => northEast!.longitude;
+  double get north => northEast!.latitude;
 
-  LatLng get southWest => _sw;
-  LatLng get northEast => _ne;
+  LatLng? get southWest => _sw;
+  LatLng? get northEast => _ne;
   LatLng get northWest => LatLng(north, west);
   LatLng get southEast => LatLng(south, east);
 
@@ -80,7 +81,7 @@ class LatLngBounds {
     return _sw != null && _ne != null;
   }
 
-  bool contains(LatLng point) {
+  bool contains(LatLng? point) {
     if (!isValid) {
       return false;
     }
@@ -90,34 +91,34 @@ class LatLngBounds {
   }
 
   bool containsBounds(LatLngBounds bounds) {
-    var sw2 = bounds._sw;
+    var sw2 = bounds._sw!;
     var ne2 = bounds._ne;
-    return (sw2.latitude >= _sw.latitude) &&
-        (ne2.latitude <= _ne.latitude) &&
-        (sw2.longitude >= _sw.longitude) &&
-        (ne2.longitude <= _ne.longitude);
+    return (sw2.latitude >= _sw!.latitude) &&
+        (ne2!.latitude <= _ne!.latitude) &&
+        (sw2.longitude >= _sw!.longitude) &&
+        (ne2.longitude <= _ne!.longitude);
   }
 
-  bool isOverlapping(LatLngBounds bounds) {
+  bool isOverlapping(LatLngBounds? bounds) {
     if (!isValid) {
       return false;
     }
     // check if bounding box rectangle is outside the other, if it is then it's
     // considered not overlapping
-    if (_sw.latitude > bounds._ne.latitude ||
-        _ne.latitude < bounds._sw.latitude ||
-        _ne.longitude < bounds._sw.longitude ||
-        _sw.longitude > bounds._ne.longitude) {
+    if (_sw!.latitude > bounds!._ne!.latitude ||
+        _ne!.latitude < bounds._sw!.latitude ||
+        _ne!.longitude < bounds._sw!.longitude ||
+        _sw!.longitude > bounds._ne!.longitude) {
       return false;
     }
     return true;
   }
 
   void pad(double bufferRatio) {
-    var heightBuffer = (_sw.latitude - _ne.latitude).abs() * bufferRatio;
-    var widthBuffer = (_sw.longitude - _ne.longitude).abs() * bufferRatio;
+    var heightBuffer = (_sw!.latitude - _ne!.latitude).abs() * bufferRatio;
+    var widthBuffer = (_sw!.longitude - _ne!.longitude).abs() * bufferRatio;
 
-    _sw = LatLng(_sw.latitude - heightBuffer, _sw.longitude - widthBuffer);
-    _ne = LatLng(_ne.latitude + heightBuffer, _ne.longitude + widthBuffer);
+    _sw = LatLng(_sw!.latitude - heightBuffer, _sw!.longitude - widthBuffer);
+    _ne = LatLng(_ne!.latitude + heightBuffer, _ne!.longitude + widthBuffer);
   }
 }
diff --git a/lib/src/gestures/gestures.dart b/lib/src/gestures/gestures.dart
index d491efc6d..bc81176a5 100644
--- a/lib/src/gestures/gestures.dart
+++ b/lib/src/gestures/gestures.dart
@@ -6,7 +6,7 @@ import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_map/src/gestures/interactive_flag.dart';
 import 'package:flutter_map/src/gestures/latlng_tween.dart';
 import 'package:flutter_map/src/map/map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 import 'package:positioned_tap_detector_2/positioned_tap_detector_2.dart';
 
 abstract class MapGestureMixin extends State<FlutterMap>
@@ -30,25 +30,25 @@ abstract class MapGestureMixin extends State<FlutterMap>
 
   // Helps to reset ScaleUpdateDetails.scale back to 1.0 when a multi finger
   // gesture wins
-  double _scaleCorrector;
+  late double _scaleCorrector;
 
-  double _lastRotation;
-  double _lastScale;
-  Offset _lastFocalLocal;
+  late double _lastRotation;
+  late double _lastScale;
+  late Offset _lastFocalLocal;
 
-  LatLng _mapCenterStart;
-  double _mapZoomStart;
-  Offset _focalStartLocal;
+  late LatLng _mapCenterStart;
+  late double _mapZoomStart;
+  late Offset _focalStartLocal;
 
-  AnimationController _flingController;
-  Animation<Offset> _flingAnimation;
+  late AnimationController _flingController;
+  late Animation<Offset> _flingAnimation;
 
-  AnimationController _doubleTapController;
-  Animation _doubleTapZoomAnimation;
-  Animation _doubleTapCenterAnimation;
+  late AnimationController _doubleTapController;
+  late Animation _doubleTapZoomAnimation;
+  late Animation _doubleTapCenterAnimation;
 
   int _tapUpCounter = 0;
-  Timer _doubleTapHoldMaxDelay;
+  Timer? _doubleTapHoldMaxDelay;
 
   @override
   FlutterMap get widget;
@@ -161,7 +161,7 @@ abstract class MapGestureMixin extends State<FlutterMap>
     }
   }
 
-  int _getMultiFingerGestureFlags({int gestureWinner, MapOptions mapOptions}) {
+  int _getMultiFingerGestureFlags({int? gestureWinner, MapOptions? mapOptions}) {
     gestureWinner ??= _gestureWinner;
     mapOptions ??= options;
 
@@ -480,7 +480,7 @@ abstract class MapGestureMixin extends State<FlutterMap>
 
     var direction = details.velocity.pixelsPerSecond / magnitude;
     var distance =
-        (Offset.zero & Size(mapState.originalSize.x, mapState.originalSize.y))
+        (Offset.zero & Size(mapState.originalSize!.x as double, mapState.originalSize!.y as double))
             .shortestSide;
 
     var _flingOffset = _focalStartLocal - _lastFocalLocal;
@@ -498,10 +498,10 @@ abstract class MapGestureMixin extends State<FlutterMap>
     closeFlingAnimationController(MapEventSource.tap);
     closeDoubleTapController(MapEventSource.tap);
 
-    final latlng = _offsetToCrs(position.relative);
+    final latlng = _offsetToCrs(position.relative!);
     if (options.onTap != null) {
       // emit the event
-      options.onTap(latlng);
+      options.onTap!(latlng);
     }
 
     mapState.emitMapEvent(
@@ -520,10 +520,10 @@ abstract class MapGestureMixin extends State<FlutterMap>
     closeFlingAnimationController(MapEventSource.longPress);
     closeDoubleTapController(MapEventSource.longPress);
 
-    final latlng = _offsetToCrs(position.relative);
+    final latlng = _offsetToCrs(position.relative!);
     if (options.onLongPress != null) {
       // emit the event
-      options.onLongPress(latlng);
+      options.onLongPress!(latlng);
     }
 
     mapState.emitMapEvent(
@@ -538,7 +538,7 @@ abstract class MapGestureMixin extends State<FlutterMap>
 
   LatLng _offsetToCrs(Offset offset) {
     final focalStartPt = mapState.project(mapState.center, mapState.zoom);
-    final point = (_offsetToPoint(offset) - (mapState.originalSize / 2.0))
+    final point = (_offsetToPoint(offset) - (mapState.originalSize! / 2.0))
         .rotate(mapState.rotationRad);
 
     var newCenterPt = focalStartPt + point;
@@ -557,10 +557,10 @@ abstract class MapGestureMixin extends State<FlutterMap>
 
     if (InteractiveFlag.hasFlag(
         options.interactiveFlags, InteractiveFlag.doubleTapZoom)) {
-      final centerPos = _pointToOffset(mapState.originalSize) / 2.0;
+      final centerPos = _pointToOffset(mapState.originalSize!) / 2.0;
       final newZoom = _getZoomForScale(mapState.zoom, 2.0);
       final focalDelta = _getDoubleTapFocalDelta(
-          centerPos, tapPosition.relative, newZoom - mapState.zoom);
+          centerPos, tapPosition.relative!, newZoom - mapState.zoom);
       final newCenter = _offsetToCrs(centerPos + focalDelta);
       _startDoubleTapAnimation(newZoom, newCenter);
     }
diff --git a/lib/src/gestures/latlng_tween.dart b/lib/src/gestures/latlng_tween.dart
index f1e376b15..145778da8 100644
--- a/lib/src/gestures/latlng_tween.dart
+++ b/lib/src/gestures/latlng_tween.dart
@@ -1,14 +1,13 @@
 import 'package:flutter/animation.dart';
-import 'package:flutter/foundation.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 class LatLngTween extends Tween<LatLng> {
-  LatLngTween({@required LatLng begin, @required LatLng end})
+  LatLngTween({required LatLng begin, required LatLng end})
       : super(begin: begin, end: end);
 
   @override
   LatLng lerp(double t) => LatLng(
-        begin.latitude + (end.latitude - begin.latitude) * t,
-        begin.longitude + (end.longitude - begin.longitude) * t,
+        begin!.latitude + (end!.latitude - begin!.latitude) * t,
+        begin!.longitude + (end!.longitude - begin!.longitude) * t,
       );
 }
diff --git a/lib/src/gestures/map_events.dart b/lib/src/gestures/map_events.dart
index 3ab472844..084b8c178 100644
--- a/lib/src/gestures/map_events.dart
+++ b/lib/src/gestures/map_events.dart
@@ -1,4 +1,4 @@
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 enum MapEventSource {
   mapController,
@@ -15,6 +15,9 @@ enum MapEventSource {
   flingAnimationController,
   doubleTapZoomAnimationController,
   interactiveFlagsChanged,
+  fitBounds,
+  initialization,
+  custom
 }
 
 abstract class MapEvent {
@@ -25,7 +28,7 @@ abstract class MapEvent {
   // current zoom when event is emitted
   final double zoom;
 
-  MapEvent({this.source, this.center, this.zoom});
+  MapEvent({required this.source, required this.center, required this.zoom});
 }
 
 abstract class MapEventWithMove extends MapEvent {
@@ -33,11 +36,11 @@ abstract class MapEventWithMove extends MapEvent {
   final double targetZoom;
 
   MapEventWithMove({
-    this.targetCenter,
-    this.targetZoom,
-    MapEventSource source,
-    LatLng center,
-    double zoom,
+    required this.targetCenter,
+    required this.targetZoom,
+    required MapEventSource source,
+    required LatLng center,
+    required double zoom,
   }) : super(source: source, center: center, zoom: zoom);
 }
 
@@ -45,10 +48,10 @@ class MapEventTap extends MapEvent {
   final LatLng tapPosition;
 
   MapEventTap({
-    this.tapPosition,
-    MapEventSource source,
-    LatLng center,
-    double zoom,
+    required this.tapPosition,
+    required MapEventSource source,
+    required LatLng center,
+    required double zoom,
   }) : super(source: source, center: center, zoom: zoom);
 }
 
@@ -56,23 +59,23 @@ class MapEventLongPress extends MapEvent {
   final LatLng tapPosition;
 
   MapEventLongPress({
-    this.tapPosition,
-    MapEventSource source,
-    LatLng center,
-    double zoom,
+    required this.tapPosition,
+    required MapEventSource source,
+    required LatLng center,
+    required double zoom,
   }) : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventMove extends MapEventWithMove {
-  final String id;
+  final String? id;
 
   MapEventMove({
     this.id,
-    LatLng targetCenter,
-    double targetZoom,
-    MapEventSource source,
-    LatLng center,
-    double zoom,
+    required LatLng targetCenter,
+    required double targetZoom,
+    required MapEventSource source,
+    required LatLng center,
+    required double zoom,
   }) : super(
           targetCenter: targetCenter,
           targetZoom: targetZoom,
@@ -83,22 +86,28 @@ class MapEventMove extends MapEventWithMove {
 }
 
 class MapEventMoveStart extends MapEvent {
-  MapEventMoveStart({MapEventSource source, LatLng center, double zoom})
+  MapEventMoveStart(
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventMoveEnd extends MapEvent {
-  MapEventMoveEnd({MapEventSource source, LatLng center, double zoom})
+  MapEventMoveEnd(
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventFlingAnimation extends MapEventWithMove {
   MapEventFlingAnimation({
-    LatLng targetCenter,
-    double targetZoom,
-    MapEventSource source,
-    LatLng center,
-    double zoom,
+    required LatLng targetCenter,
+    required double targetZoom,
+    required MapEventSource source,
+    required LatLng center,
+    required double zoom,
   }) : super(
           targetCenter: targetCenter,
           targetZoom: targetZoom,
@@ -112,28 +121,35 @@ class MapEventFlingAnimation extends MapEventWithMove {
 /// to start fling animation
 class MapEventFlingAnimationNotStarted extends MapEvent {
   MapEventFlingAnimationNotStarted(
-      {MapEventSource source, LatLng center, double zoom})
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventFlingAnimationStart extends MapEvent {
   MapEventFlingAnimationStart(
-      {MapEventSource source, LatLng center, double zoom})
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventFlingAnimationEnd extends MapEvent {
-  MapEventFlingAnimationEnd({MapEventSource source, LatLng center, double zoom})
+  MapEventFlingAnimationEnd(
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventDoubleTapZoom extends MapEventWithMove {
   MapEventDoubleTapZoom({
-    LatLng targetCenter,
-    double targetZoom,
-    MapEventSource source,
-    LatLng center,
-    double zoom,
+    required LatLng targetCenter,
+    required double targetZoom,
+    required MapEventSource source,
+    required LatLng center,
+    required double zoom,
   }) : super(
           targetCenter: targetCenter,
           targetZoom: targetZoom,
@@ -145,36 +161,47 @@ class MapEventDoubleTapZoom extends MapEventWithMove {
 
 class MapEventDoubleTapZoomStart extends MapEvent {
   MapEventDoubleTapZoomStart(
-      {MapEventSource source, LatLng center, double zoom})
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventDoubleTapZoomEnd extends MapEvent {
-  MapEventDoubleTapZoomEnd({MapEventSource source, LatLng center, double zoom})
+  MapEventDoubleTapZoomEnd(
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventRotate extends MapEvent {
-  final String id;
+  final String? id;
   final double currentRotation;
   final double targetRotation;
 
   MapEventRotate({
-    this.id,
-    this.currentRotation,
-    this.targetRotation,
-    MapEventSource source,
-    LatLng center,
-    double zoom,
+    required this.id,
+    required this.currentRotation,
+    required this.targetRotation,
+    required MapEventSource source,
+    required LatLng center,
+    required double zoom,
   }) : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventRotateStart extends MapEvent {
-  MapEventRotateStart({MapEventSource source, LatLng center, double zoom})
+  MapEventRotateStart(
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
 
 class MapEventRotateEnd extends MapEvent {
-  MapEventRotateEnd({MapEventSource source, LatLng center, double zoom})
+  MapEventRotateEnd(
+      {required MapEventSource source,
+      required LatLng center,
+      required double zoom})
       : super(source: source, center: center, zoom: zoom);
 }
diff --git a/lib/src/layer/circle_layer.dart b/lib/src/layer/circle_layer.dart
index 0f79d95f0..8f7c14804 100644
--- a/lib/src/layer/circle_layer.dart
+++ b/lib/src/layer/circle_layer.dart
@@ -3,14 +3,14 @@ import 'dart:ui';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_map/src/map/map.dart';
-import 'package:latlong/latlong.dart' hide Path;
+import 'package:latlong2/latlong.dart' hide Path;
 
 class CircleLayerOptions extends LayerOptions {
   final List<CircleMarker> circles;
   CircleLayerOptions({
-    Key key,
+    Key? key,
     this.circles = const [],
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
   }) : super(key: key, rebuild: rebuild);
 }
 
@@ -24,8 +24,8 @@ class CircleMarker {
   Offset offset = Offset.zero;
   num realRadius = 0;
   CircleMarker({
-    this.point,
-    this.radius,
+    required this.point,
+    required this.radius,
     this.useRadiusInMeter = false,
     this.color = const Color(0xFF00FF00),
     this.borderStrokeWidth = 0.0,
@@ -36,11 +36,11 @@ class CircleMarker {
 class CircleLayerWidget extends StatelessWidget {
   final CircleLayerOptions options;
 
-  CircleLayerWidget({Key key, @required this.options}) : super(key: key);
+  CircleLayerWidget({Key? key, required this.options}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
-    final mapState = MapState.of(context);
+    final mapState = MapState.maybeOf(context)!;
     return CircleLayer(options, mapState, mapState.onMoved);
   }
 }
@@ -48,7 +48,7 @@ class CircleLayerWidget extends StatelessWidget {
 class CircleLayer extends StatelessWidget {
   final CircleLayerOptions circleOpts;
   final MapState map;
-  final Stream<Null> stream;
+  final Stream<Null>? stream;
   CircleLayer(this.circleOpts, this.map, this.stream)
       : super(key: circleOpts.key);
 
@@ -112,8 +112,11 @@ class CirclePainter extends CustomPainter {
       ..style = PaintingStyle.fill
       ..color = circle.color;
 
-    _paintCircle(canvas, circle.offset,
-        circle.useRadiusInMeter ? circle.realRadius : circle.radius, paint);
+    _paintCircle(
+        canvas,
+        circle.offset,
+        circle.useRadiusInMeter ? circle.realRadius as double : circle.radius,
+        paint);
 
     if (circle.borderStrokeWidth > 0) {
       final paint = Paint()
@@ -121,8 +124,11 @@ class CirclePainter extends CustomPainter {
         ..color = circle.borderColor
         ..strokeWidth = circle.borderStrokeWidth;
 
-      _paintCircle(canvas, circle.offset,
-          circle.useRadiusInMeter ? circle.realRadius : circle.radius, paint);
+      _paintCircle(
+          canvas,
+          circle.offset,
+          circle.useRadiusInMeter ? circle.realRadius as double : circle.radius,
+          paint);
     }
   }
 
diff --git a/lib/src/layer/group_layer.dart b/lib/src/layer/group_layer.dart
index 91cbe36bc..68b79761a 100644
--- a/lib/src/layer/group_layer.dart
+++ b/lib/src/layer/group_layer.dart
@@ -7,20 +7,20 @@ class GroupLayerOptions extends LayerOptions {
   List<LayerOptions> group = <LayerOptions>[];
 
   GroupLayerOptions({
-    Key key,
-    this.group,
-    Stream<Null> rebuild,
+    required Key key,
+    required this.group,
+    required Stream<Null> rebuild,
   }) : super(key: key, rebuild: rebuild);
 }
 
 class GroupLayerWidget extends StatelessWidget {
   final GroupLayerOptions options;
 
-  GroupLayerWidget({Key key, @required this.options}) : super(key: key);
+  GroupLayerWidget({Key? key, required this.options}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
-    final mapState = MapState.of(context);
+    final mapState = MapState.maybeOf(context)!;
     return GroupLayer(options, mapState, mapState.onMoved);
   }
 }
diff --git a/lib/src/layer/layer.dart b/lib/src/layer/layer.dart
index 7105fd0eb..cf4cb0801 100644
--- a/lib/src/layer/layer.dart
+++ b/lib/src/layer/layer.dart
@@ -5,7 +5,7 @@ import 'package:flutter/foundation.dart';
 /// All LayerOptions have access to a stream that notifies when the map needs
 /// rebuilding.
 class LayerOptions {
-  final Key key;
-  final Stream<Null> rebuild;
+  final Key? key;
+  final Stream<Null>? rebuild;
   LayerOptions({this.key, this.rebuild});
 }
diff --git a/lib/src/layer/marker_layer.dart b/lib/src/layer/marker_layer.dart
index c23978fab..426c0317c 100644
--- a/lib/src/layer/marker_layer.dart
+++ b/lib/src/layer/marker_layer.dart
@@ -2,14 +2,14 @@ import 'package:flutter/widgets.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_map/src/core/bounds.dart';
 import 'package:flutter_map/src/map/map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 class MarkerLayerOptions extends LayerOptions {
   final List<Marker> markers;
   MarkerLayerOptions({
-    Key key,
+    Key? key,
     this.markers = const [],
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
   }) : super(key: key, rebuild: rebuild);
 }
 
@@ -51,8 +51,8 @@ class Anchor {
     }
   }
 
-  factory Anchor.forPos(AnchorPos pos, double width, double height) {
-    if (pos == null) return Anchor._(width, height, null);
+  factory Anchor.forPos(AnchorPos? pos, double width, double height) {
+    if (pos == null) return Anchor._(width, height, AnchorAlign.none);
     if (pos.value is AnchorAlign) return Anchor._(width, height, pos.value);
     if (pos.value is Anchor) return pos.value;
     throw Exception('Unsupported AnchorPos value type: ${pos.runtimeType}.');
@@ -67,6 +67,7 @@ class AnchorPos<T> {
 }
 
 enum AnchorAlign {
+  none,
   left,
   right,
   top,
@@ -82,22 +83,22 @@ class Marker {
   final Anchor anchor;
 
   Marker({
-    this.point,
-    this.builder,
+    required this.point,
+    required this.builder,
     this.width = 30.0,
     this.height = 30.0,
-    AnchorPos anchorPos,
+    AnchorPos? anchorPos,
   }) : anchor = Anchor.forPos(anchorPos, width, height);
 }
 
 class MarkerLayerWidget extends StatelessWidget {
   final MarkerLayerOptions options;
 
-  MarkerLayerWidget({Key key, @required this.options}) : super(key: key);
+  MarkerLayerWidget({Key? key, required this.options}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
-    final mapState = MapState.of(context);
+    final mapState = MapState.maybeOf(context)!;
     return MarkerLayer(options, mapState, mapState.onMoved);
   }
 }
@@ -105,7 +106,7 @@ class MarkerLayerWidget extends StatelessWidget {
 class MarkerLayer extends StatelessWidget {
   final MarkerLayerOptions markerOpts;
   final MapState map;
-  final Stream<Null> stream;
+  final Stream<Null>? stream;
 
   MarkerLayer(this.markerOpts, this.map, this.stream)
       : super(key: markerOpts.key);
@@ -123,9 +124,9 @@ class MarkerLayer extends StatelessWidget {
 
   @override
   Widget build(BuildContext context) {
-    return StreamBuilder<int>(
+    return StreamBuilder<int?>(
       stream: stream, // a Stream<int> or null
-      builder: (BuildContext context, AsyncSnapshot<int> snapshot) {
+      builder: (BuildContext context, AsyncSnapshot<int?> snapshot) {
         var markers = <Widget>[];
         for (var markerOpt in markerOpts.markers) {
           var pos = map.project(markerOpt.point);
diff --git a/lib/src/layer/overlay_image_layer.dart b/lib/src/layer/overlay_image_layer.dart
index a753c6aab..137c63155 100644
--- a/lib/src/layer/overlay_image_layer.dart
+++ b/lib/src/layer/overlay_image_layer.dart
@@ -9,9 +9,9 @@ class OverlayImageLayerOptions extends LayerOptions {
   final List<OverlayImage> overlayImages;
 
   OverlayImageLayerOptions({
-    Key key,
+    Key? key,
     this.overlayImages = const [],
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
   }) : super(key: key, rebuild: rebuild);
 }
 
@@ -22,8 +22,8 @@ class OverlayImage {
   final bool gaplessPlayback;
 
   OverlayImage({
-    this.bounds,
-    this.imageProvider,
+    required this.bounds,
+    required this.imageProvider,
     this.opacity = 1.0,
     this.gaplessPlayback = false,
   });
@@ -32,11 +32,11 @@ class OverlayImage {
 class OverlayImageLayerWidget extends StatelessWidget {
   final OverlayImageLayerOptions options;
 
-  OverlayImageLayerWidget({Key key, @required this.options}) : super(key: key);
+  OverlayImageLayerWidget({Key? key, required this.options}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
-    final mapState = MapState.of(context);
+    final mapState = MapState.maybeOf(context)!;
     return OverlayImageLayer(options, mapState, mapState.onMoved);
   }
 }
@@ -44,7 +44,7 @@ class OverlayImageLayerWidget extends StatelessWidget {
 class OverlayImageLayer extends StatelessWidget {
   final OverlayImageLayerOptions overlayImageOpts;
   final MapState map;
-  final Stream<Null> stream;
+  final Stream<Null>? stream;
 
   OverlayImageLayer(this.overlayImageOpts, this.map, this.stream)
       : super(key: overlayImageOpts.key);
diff --git a/lib/src/layer/polygon_layer.dart b/lib/src/layer/polygon_layer.dart
index 40739677e..7284aec53 100644
--- a/lib/src/layer/polygon_layer.dart
+++ b/lib/src/layer/polygon_layer.dart
@@ -4,7 +4,7 @@ import 'dart:ui';
 import 'package:flutter/widgets.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_map/src/map/map.dart';
-import 'package:latlong/latlong.dart' hide Path; // conflict with Path from UI
+import 'package:latlong2/latlong.dart' hide Path; // conflict with Path from UI
 
 class PolygonLayerOptions extends LayerOptions {
   final List<Polygon> polygons;
@@ -12,10 +12,10 @@ class PolygonLayerOptions extends LayerOptions {
 
   /// screen space culling of polygons based on bounding box
   PolygonLayerOptions({
-    Key key,
+    Key? key,
     this.polygons = const [],
     this.polygonCulling = false,
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
   }) : super(key: key, rebuild: rebuild) {
     if (polygonCulling) {
       for (var polygon in polygons) {
@@ -28,17 +28,17 @@ class PolygonLayerOptions extends LayerOptions {
 class Polygon {
   final List<LatLng> points;
   final List<Offset> offsets = [];
-  final List<List<LatLng>> holePointsList;
-  final List<List<Offset>> holeOffsetsList;
+  final List<List<LatLng>>? holePointsList;
+  final List<List<Offset>>? holeOffsetsList;
   final Color color;
   final double borderStrokeWidth;
   final Color borderColor;
   final bool disableHolesBorder;
   final bool isDotted;
-  LatLngBounds boundingBox;
+  late LatLngBounds boundingBox;
 
   Polygon({
-    this.points,
+    required this.points,
     this.holePointsList,
     this.color = const Color(0xFF00FF00),
     this.borderStrokeWidth = 0.0,
@@ -52,11 +52,11 @@ class Polygon {
 
 class PolygonLayerWidget extends StatelessWidget {
   final PolygonLayerOptions options;
-  PolygonLayerWidget({Key key, @required this.options}) : super(key: key);
+  PolygonLayerWidget({Key? key, required this.options}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
-    final mapState = MapState.of(context);
+    final mapState = MapState.maybeOf(context)!;
     return PolygonLayer(options, mapState, mapState.onMoved);
   }
 }
@@ -64,7 +64,7 @@ class PolygonLayerWidget extends StatelessWidget {
 class PolygonLayer extends StatelessWidget {
   final PolygonLayerOptions polygonOpts;
   final MapState map;
-  final Stream stream;
+  final Stream<Null>? stream;
 
   PolygonLayer(this.polygonOpts, this.map, this.stream)
       : super(key: polygonOpts.key);
@@ -89,7 +89,7 @@ class PolygonLayer extends StatelessWidget {
           polygon.offsets.clear();
 
           if (null != polygon.holeOffsetsList) {
-            for (var offsets in polygon.holeOffsetsList) {
+            for (var offsets in polygon.holeOffsetsList!) {
               offsets.clear();
             }
           }
@@ -103,9 +103,11 @@ class PolygonLayer extends StatelessWidget {
           _fillOffsets(polygon.offsets, polygon.points);
 
           if (null != polygon.holePointsList) {
-            for (var i = 0, len = polygon.holePointsList.length; i < len; ++i) {
+            for (var i = 0, len = polygon.holePointsList!.length;
+                i < len;
+                ++i) {
               _fillOffsets(
-                  polygon.holeOffsetsList[i], polygon.holePointsList[i]);
+                  polygon.holeOffsetsList![i], polygon.holePointsList![i]);
             }
           }
 
@@ -170,7 +172,7 @@ class PolygonPainter extends CustomPainter {
 
         if (!polygonOpt.disableHolesBorder &&
             null != polygonOpt.holeOffsetsList) {
-          for (var offsets in polygonOpt.holeOffsetsList) {
+          for (var offsets in polygonOpt.holeOffsetsList!) {
             _paintDottedLine(
                 canvas, offsets, borderRadius, spacing, borderPaint);
           }
@@ -180,7 +182,7 @@ class PolygonPainter extends CustomPainter {
 
         if (!polygonOpt.disableHolesBorder &&
             null != polygonOpt.holeOffsetsList) {
-          for (var offsets in polygonOpt.holeOffsetsList) {
+          for (var offsets in polygonOpt.holeOffsetsList!) {
             _paintLine(canvas, offsets, borderRadius, borderPaint);
           }
         }
@@ -225,7 +227,7 @@ class PolygonPainter extends CustomPainter {
       canvas.saveLayer(rect, paint);
       paint.style = PaintingStyle.fill;
 
-      for (var offsets in polygonOpt.holeOffsetsList) {
+      for (var offsets in polygonOpt.holeOffsetsList!) {
         var path = Path();
         path.addPolygon(offsets, true);
         canvas.drawPath(path, paint);
diff --git a/lib/src/layer/polyline_layer.dart b/lib/src/layer/polyline_layer.dart
index b5d286bae..b114748bb 100644
--- a/lib/src/layer/polyline_layer.dart
+++ b/lib/src/layer/polyline_layer.dart
@@ -4,17 +4,17 @@ import 'dart:ui' as ui;
 import 'package:flutter/widgets.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_map/src/map/map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 class PolylineLayerOptions extends LayerOptions {
   final List<Polyline> polylines;
   final bool polylineCulling;
 
   PolylineLayerOptions({
-    Key key,
+    Key? key,
     this.polylines = const [],
     this.polylineCulling = false,
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
   }) : super(key: key, rebuild: rebuild) {
     if (polylineCulling) {
       for (var polyline in polylines) {
@@ -30,14 +30,14 @@ class Polyline {
   final double strokeWidth;
   final Color color;
   final double borderStrokeWidth;
-  final Color borderColor;
-  final List<Color> gradientColors;
-  final List<double> colorsStop;
+  final Color? borderColor;
+  final List<Color>? gradientColors;
+  final List<double>? colorsStop;
   final bool isDotted;
-  LatLngBounds boundingBox;
+  late LatLngBounds boundingBox;
 
   Polyline({
-    this.points,
+    required this.points,
     this.strokeWidth = 1.0,
     this.color = const Color(0xFF00FF00),
     this.borderStrokeWidth = 0.0,
@@ -50,11 +50,11 @@ class Polyline {
 
 class PolylineLayerWidget extends StatelessWidget {
   final PolylineLayerOptions options;
-  PolylineLayerWidget({Key key, @required this.options}) : super(key: key);
+  PolylineLayerWidget({Key? key, required this.options}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
-    final mapState = MapState.of(context);
+    final mapState = MapState.maybeOf(context)!;
     return PolylineLayer(options, mapState, mapState.onMoved);
   }
 }
@@ -62,7 +62,7 @@ class PolylineLayerWidget extends StatelessWidget {
 class PolylineLayer extends StatelessWidget {
   final PolylineLayerOptions polylineOpts;
   final MapState map;
-  final Stream<Null> stream;
+  final Stream<Null>? stream;
 
   PolylineLayer(this.polylineOpts, this.map, this.stream)
       : super(key: polylineOpts.key);
@@ -145,15 +145,15 @@ class PolylinePainter extends CustomPainter {
     if (polylineOpt.gradientColors == null) {
       paint.color = polylineOpt.color;
     } else {
-      polylineOpt.gradientColors.isNotEmpty
+      polylineOpt.gradientColors!.isNotEmpty
           ? paint.shader = _paintGradient()
           : paint.color = polylineOpt.color;
     }
 
-    Paint filterPaint;
+    Paint? filterPaint;
     if (polylineOpt.borderColor != null) {
       filterPaint = Paint()
-        ..color = polylineOpt.borderColor.withAlpha(255)
+        ..color = polylineOpt.borderColor!.withAlpha(255)
         ..strokeWidth = polylineOpt.strokeWidth
         ..strokeCap = StrokeCap.round
         ..strokeJoin = StrokeJoin.round
@@ -162,7 +162,7 @@ class PolylinePainter extends CustomPainter {
 
     final borderPaint = polylineOpt.borderStrokeWidth > 0.0
         ? (Paint()
-          ..color = polylineOpt.borderColor
+          ..color = polylineOpt.borderColor ?? Color(0x00000000)
           ..strokeWidth =
               polylineOpt.strokeWidth + polylineOpt.borderStrokeWidth
           ..strokeCap = StrokeCap.round
@@ -174,7 +174,7 @@ class PolylinePainter extends CustomPainter {
     if (polylineOpt.isDotted) {
       var spacing = polylineOpt.strokeWidth * 1.5;
       canvas.saveLayer(rect, Paint());
-      if (borderPaint != null) {
+      if (borderPaint != null && filterPaint != null) {
         _paintDottedLine(
             canvas, polylineOpt.offsets, borderRadius, spacing, borderPaint);
         _paintDottedLine(
@@ -185,12 +185,10 @@ class PolylinePainter extends CustomPainter {
     } else {
       paint.style = PaintingStyle.stroke;
       canvas.saveLayer(rect, Paint());
-      if (borderPaint != null) {
-        if (filterPaint != null) {
-          filterPaint.style = PaintingStyle.stroke;
-          _paintLine(canvas, polylineOpt.offsets, borderPaint);
-        }
-        borderPaint?.style = PaintingStyle.stroke;
+      if (borderPaint != null && filterPaint != null) {
+        borderPaint.style = PaintingStyle.stroke;
+        _paintLine(canvas, polylineOpt.offsets, borderPaint);
+        filterPaint.style = PaintingStyle.stroke;
         _paintLine(canvas, polylineOpt.offsets, filterPaint);
       }
       _paintLine(canvas, polylineOpt.offsets, paint);
@@ -234,18 +232,18 @@ class PolylinePainter extends CustomPainter {
   }
 
   ui.Gradient _paintGradient() => ui.Gradient.linear(polylineOpt.offsets.first,
-      polylineOpt.offsets.last, polylineOpt.gradientColors, _getColorsStop());
+      polylineOpt.offsets.last, polylineOpt.gradientColors!, _getColorsStop());
 
-  List<double> _getColorsStop() => (polylineOpt.colorsStop != null &&
-          polylineOpt.colorsStop.length == polylineOpt.gradientColors.length)
+  List<double>? _getColorsStop() => (polylineOpt.colorsStop != null &&
+          polylineOpt.colorsStop!.length == polylineOpt.gradientColors!.length)
       ? polylineOpt.colorsStop
       : _calculateColorsStop();
 
   List<double> _calculateColorsStop() {
-    final colorsStopInterval = 1.0 / polylineOpt.gradientColors.length;
-    return polylineOpt.gradientColors
+    final colorsStopInterval = 1.0 / polylineOpt.gradientColors!.length;
+    return polylineOpt.gradientColors!
         .map((gradientColor) =>
-            polylineOpt.gradientColors.indexOf(gradientColor) *
+            polylineOpt.gradientColors!.indexOf(gradientColor) *
             colorsStopInterval)
         .toList();
   }
diff --git a/lib/src/layer/tile_layer.dart b/lib/src/layer/tile_layer.dart
index 8033578ce..134dc92f4 100644
--- a/lib/src/layer/tile_layer.dart
+++ b/lib/src/layer/tile_layer.dart
@@ -11,7 +11,7 @@ import 'package:flutter_map/src/geo/crs/crs.dart';
 import 'package:flutter_map/src/layer/tile_builder/tile_builder.dart';
 import 'package:flutter_map/src/layer/tile_provider/tile_provider.dart';
 import 'package:flutter_map/src/map/map.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 import 'package:tuple/tuple.dart';
 
 import 'layer.dart';
@@ -49,14 +49,14 @@ class TileLayerOptions extends LayerOptions {
   /// Is translated to this:
   ///
   /// https://a.tile.openstreetmap.org/12/2177/1259.png
-  final String urlTemplate;
+  final String? urlTemplate;
 
   /// If `true`, inverses Y axis numbering for tiles (turn this on for
   /// [TMS](https://en.wikipedia.org/wiki/Tile_Map_Service) services).
   final bool tms;
 
   /// If not `null`, then tiles will pull's WMS protocol requests
-  final WMSTileLayerOptions wmsOptions;
+  final WMSTileLayerOptions? wmsOptions;
 
   /// Size for the tile.
   /// Default is 256
@@ -73,12 +73,12 @@ class TileLayerOptions extends LayerOptions {
   /// Minimum zoom number the tile source has available. If it is specified, the
   /// tiles on all zoom levels lower than minNativeZoom will be loaded from
   /// minNativeZoom level and auto-scaled.
-  final double minNativeZoom;
+  final double? minNativeZoom;
 
   /// Maximum zoom number the tile source has available. If it is specified, the
   /// tiles on all zoom levels higher than maxNativeZoom will be loaded from
   /// maxNativeZoom level and auto-scaled.
-  final double maxNativeZoom;
+  final double? maxNativeZoom;
 
   /// If set to true, the zoom number used in tile URLs will be reversed
   /// (`maxZoom - zoom` instead of `zoom`)
@@ -141,10 +141,10 @@ class TileLayerOptions extends LayerOptions {
   final int keepBuffer;
 
   /// Placeholder to show until tile images are fetched by the provider.
-  final ImageProvider placeholderImage;
+  final ImageProvider? placeholderImage;
 
   /// Tile image to show in place of the tile that failed to load.
-  final ImageProvider errorImage;
+  final ImageProvider? errorImage;
 
   /// Static informations that should replace placeholders in the [urlTemplate].
   /// Applying API keys is a good example on how to use this parameter.
@@ -170,11 +170,11 @@ class TileLayerOptions extends LayerOptions {
   /// loading tiles every frame when panning / zooming, flutter is fast) This
   /// can save some fps and even bandwidth (ie. when fast panning / animating
   /// between long distances in short time)
-  final Duration updateInterval;
+  final Duration? updateInterval;
 
   /// Tiles fade in duration in milliseconds (default 100). This can be null to
   /// avoid fade in.
-  final Duration tileFadeInDuration;
+  final Duration? tileFadeInDuration;
 
   /// Opacity start value when Tile starts fade in (0.0 - 1.0) Takes effect if
   /// `tileFadeInDuration` is not null
@@ -210,17 +210,17 @@ class TileLayerOptions extends LayerOptions {
   final bool retinaMode;
 
   /// This callback will be execute if some errors occur when fetching tiles.
-  final ErrorTileCallBack errorTileCallback;
+  final ErrorTileCallBack? errorTileCallback;
 
   final TemplateFunction templateFunction;
 
   /// Function which may Wrap Tile with custom Widget
   /// There are predefined examples in 'tile_builder.dart'
-  final TileBuilder tileBuilder;
+  final TileBuilder? tileBuilder;
 
   /// Function which may wrap Tiles Container with custom Widget
   /// There are predefined examples in 'tile_builder.dart'
-  final TilesContainerBuilder tilesContainerBuilder;
+  final TilesContainerBuilder? tilesContainerBuilder;
 
   // If a Tile was loaded with error and if strategy isn't `none` then TileProvider
   // will be asked to evict Image based on current strategy
@@ -228,7 +228,7 @@ class TileLayerOptions extends LayerOptions {
   final EvictErrorTileStrategy evictErrorTileStrategy;
 
   TileLayerOptions({
-    Key key,
+    Key? key,
     this.urlTemplate,
     double tileSize = 256.0,
     double minZoom = 0.0,
@@ -237,7 +237,7 @@ class TileLayerOptions extends LayerOptions {
     this.maxNativeZoom,
     this.zoomReverse = false,
     double zoomOffset = 0.0,
-    Map<String, String> additionalOptions,
+    Map<String, String>? additionalOptions,
     this.subdomains = const <String>[],
     this.keepBuffer = 2,
     this.backgroundColor = const Color(0xFFE0E0E0),
@@ -264,7 +264,7 @@ class TileLayerOptions extends LayerOptions {
     this.overrideTilesWhenUrlChanges = false,
     this.retinaMode = false,
     this.errorTileCallback,
-    Stream<Null> rebuild,
+    Stream<Null>? rebuild,
     this.templateFunction = util.template,
     this.tileBuilder,
     this.tilesContainerBuilder,
@@ -328,12 +328,12 @@ class WMSTileLayerOptions {
   /// other request parameters
   final Map<String, String> otherParameters;
 
-  String _encodedBaseUrl;
+  late String _encodedBaseUrl;
 
-  double _versionNumber;
+  late double _versionNumber;
 
   WMSTileLayerOptions({
-    @required this.baseUrl,
+    required this.baseUrl,
     this.layers = const [],
     this.styles = const [],
     this.format = 'image/png',
@@ -366,8 +366,8 @@ class WMSTileLayerOptions {
     final tileSizePoint = CustomPoint(tileSize, tileSize);
     final nvPoint = coords.scaleBy(tileSizePoint);
     final sePoint = nvPoint + tileSizePoint;
-    final nvCoords = crs.pointToLatLng(nvPoint, coords.z);
-    final seCoords = crs.pointToLatLng(sePoint, coords.z);
+    final nvCoords = crs.pointToLatLng(nvPoint, coords.z as double)!;
+    final seCoords = crs.pointToLatLng(sePoint, coords.z as double)!;
     final nv = crs.projection.project(nvCoords);
     final se = crs.projection.project(seCoords);
     final bounds = Bounds(nv, se);
@@ -386,11 +386,11 @@ class WMSTileLayerOptions {
 class TileLayerWidget extends StatelessWidget {
   final TileLayerOptions options;
 
-  TileLayerWidget({Key key, @required this.options}) : super(key: key);
+  TileLayerWidget({Key? key, required this.options}) : super(key: key);
 
   @override
   Widget build(BuildContext context) {
-    final mapState = MapState.of(context);
+    final mapState = MapState.maybeOf(context)!;
 
     return TileLayer(
       mapState: mapState,
@@ -406,9 +406,9 @@ class TileLayer extends StatefulWidget {
   final Stream<Null> stream;
 
   TileLayer({
-    this.options,
-    this.mapState,
-    this.stream,
+    required this.options,
+    required this.mapState,
+    required this.stream,
   }) : super(key: options.key);
 
   @override
@@ -421,16 +421,16 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
   MapState get map => widget.mapState;
 
   TileLayerOptions get options => widget.options;
-  Bounds _globalTileRange;
-  Tuple2<double, double> _wrapX;
-  Tuple2<double, double> _wrapY;
-  double _tileZoom;
+  late Bounds _globalTileRange;
+  Tuple2<double, double>? _wrapX;
+  Tuple2<double, double>? _wrapY;
+  double? _tileZoom;
 
   //ignore: unused_field
-  Level _level;
-  StreamSubscription _moveSub;
-  StreamController<LatLng> _throttleUpdate;
-  CustomPoint _tileSize;
+  Level? _level;
+  StreamSubscription? _moveSub;
+  StreamController<LatLng?>? _throttleUpdate;
+  late CustomPoint _tileSize;
 
   final Map<String, Tile> _tiles = {};
   final Map<double, Level> _levels = {};
@@ -498,8 +498,8 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
 
   bool _isZoomOutsideMinMax() {
     for (var tile in _tiles.values) {
-      if (tile.level.zoom > (options.maxZoom ?? 1.0) ||
-          tile.level.zoom < (options.minZoom ?? 20.0)) {
+      if (tile.level.zoom > (options.maxZoom) ||
+          tile.level.zoom < (options.minZoom)) {
         return true;
       }
     }
@@ -510,10 +510,10 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     if (options.updateInterval == null) {
       _throttleUpdate = null;
     } else {
-      _throttleUpdate = StreamController<LatLng>(sync: true);
-      _throttleUpdate.stream
+      _throttleUpdate = StreamController<LatLng?>(sync: true);
+      _throttleUpdate!.stream
           .transform(
-            util.throttleStreamTransformerWithTrailingCall<LatLng>(
+            util.throttleStreamTransformerWithTrailingCall<LatLng?>(
               options.updateInterval,
             ),
           )
@@ -549,7 +549,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
         color: options.backgroundColor,
         child: options.tilesContainerBuilder == null
             ? tilesContainer
-            : options.tilesContainerBuilder(
+            : options.tilesContainerBuilder!(
                 context,
                 tilesContainer,
                 tilesToRender,
@@ -563,8 +563,8 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     var level = tile.level;
     var tileSize = getTileSize();
     var pos = (tilePos).multiplyBy(level.scale) + level.translatePoint;
-    var width = tileSize.x * level.scale;
-    var height = tileSize.y * level.scale;
+    num width = tileSize.x * level.scale;
+    num height = tileSize.y * level.scale;
 
     final Widget content = AnimatedTile(
       tile: tile,
@@ -595,7 +595,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     }
 
     for (var key in toRemove) {
-      var tile = _tiles[key];
+      var tile = _tiles[key]!;
 
       tile.tileReady = null;
       tile.dispose(tile.loadError &&
@@ -618,7 +618,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     return false;
   }
 
-  Level _updateLevels() {
+  Level? _updateLevels() {
     var zoom = _tileZoom;
     var maxZoom = options.maxZoom;
 
@@ -647,8 +647,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     if (level == null) {
       level = _levels[zoom] = Level();
       level.zIndex = maxZoom;
-      level.origin = map.project(map.unproject(map.getPixelOrigin()), zoom) ??
-          CustomPoint(0.0, 0.0);
+      level.origin = map.project(map.unproject(map.getPixelOrigin()), zoom);
       level.zoom = zoom;
 
       _setZoomTransform(level, map.center, map.zoom);
@@ -658,6 +657,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
   }
 
   void _pruneTiles() {
+    // TODO this pretty sure isn't necessary anymore
     if (map == null) {
       return;
     }
@@ -776,21 +776,20 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
   }
 
   double _clampZoom(double zoom) {
-    if (null != options.minNativeZoom && zoom < options.minNativeZoom) {
-      return options.minNativeZoom;
+    if (null != options.minNativeZoom && zoom < options.minNativeZoom!) {
+      return options.minNativeZoom!;
     }
 
-    if (null != options.maxNativeZoom && options.maxNativeZoom < zoom) {
-      return options.maxNativeZoom;
+    if (null != options.maxNativeZoom && options.maxNativeZoom! < zoom) {
+      return options.maxNativeZoom!;
     }
 
     return zoom;
   }
 
   void _setView(LatLng center, double zoom) {
-    var tileZoom = _clampZoom(zoom.roundToDouble());
-    if ((options.maxZoom != null && tileZoom > options.maxZoom) ||
-        (options.minZoom != null && tileZoom < options.minZoom)) {
+    double? tileZoom = _clampZoom(zoom.roundToDouble());
+    if ((tileZoom > options.maxZoom) || (tileZoom < options.minZoom)) {
       tileZoom = null;
     }
 
@@ -810,7 +809,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
 
   void _setZoomTransforms(LatLng center, double zoom) {
     for (var i in _levels.keys) {
-      _setZoomTransform(_levels[i], center, zoom);
+      _setZoomTransform(_levels[i]!, center, zoom);
     }
   }
 
@@ -820,7 +819,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     if (level.origin == null) {
       return;
     }
-    var translate = level.origin.multiplyBy(scale) - pixelOrigin;
+    var translate = level.origin!.multiplyBy(scale) - pixelOrigin;
     level.translatePoint = translate;
     level.scale = scale;
   }
@@ -839,23 +838,23 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     // wrapping
     _wrapX = crs.wrapLng;
     if (_wrapX != null) {
-      var first =
-          (map.project(LatLng(0.0, crs.wrapLng.item1), tileZoom).x / tileSize.x)
-              .floorToDouble();
-      var second =
-          (map.project(LatLng(0.0, crs.wrapLng.item2), tileZoom).x / tileSize.y)
-              .ceilToDouble();
+      var first = (map.project(LatLng(0.0, crs.wrapLng!.item1), tileZoom).x /
+              tileSize.x)
+          .floorToDouble();
+      var second = (map.project(LatLng(0.0, crs.wrapLng!.item2), tileZoom).x /
+              tileSize.y)
+          .ceilToDouble();
       _wrapX = Tuple2(first, second);
     }
 
     _wrapY = crs.wrapLat;
     if (_wrapY != null) {
-      var first =
-          (map.project(LatLng(crs.wrapLat.item1, 0.0), tileZoom).y / tileSize.x)
-              .floorToDouble();
-      var second =
-          (map.project(LatLng(crs.wrapLat.item2, 0.0), tileZoom).y / tileSize.y)
-              .ceilToDouble();
+      var first = (map.project(LatLng(crs.wrapLat!.item1, 0.0), tileZoom).y /
+              tileSize.x)
+          .floorToDouble();
+      var second = (map.project(LatLng(crs.wrapLat!.item2, 0.0), tileZoom).y /
+              tileSize.y)
+          .ceilToDouble();
       _wrapY = Tuple2(first, second);
     }
   }
@@ -866,8 +865,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     if (_tileZoom == null) {
       // if there is no _tileZoom available it means we are out within zoom level
       // we will restore fully via _setView call if we are back on trail
-      if ((options.maxZoom != null && tileZoom <= options.maxZoom) &&
-          (options.minZoom != null && tileZoom >= options.minZoom)) {
+      if ((tileZoom <= options.maxZoom) && (tileZoom >= options.minZoom)) {
         _tileZoom = tileZoom;
         setState(() {
           _setView(map.center, tileZoom);
@@ -877,7 +875,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
       }
     } else {
       setState(() {
-        if ((tileZoom - _tileZoom).abs() >= 1) {
+        if ((tileZoom - _tileZoom!).abs() >= 1) {
           // It was a zoom lvl change
           _setView(map.center, tileZoom);
 
@@ -886,7 +884,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
           if (null == _throttleUpdate) {
             _update(null);
           } else {
-            _throttleUpdate.add(null);
+            _throttleUpdate!.add(null);
           }
 
           _setZoomTransforms(map.center, map.zoom);
@@ -905,7 +903,8 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
 
   // Private method to load tiles in the grid's active zoom level according to
   // map bounds
-  void _update(LatLng center) {
+  void _update(LatLng? center) {
+    // TODO can we safely remove the null check for map
     if (map == null || _tileZoom == null) {
       return;
     }
@@ -916,7 +915,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     var pixelBounds = _getTiledPixelBounds(center);
     var tileRange = _pxBoundsToTileRange(pixelBounds);
     var tileCenter = tileRange.getCenter();
-    var queue = <Coords<num>>[];
+    final queue = <Coords<num>>[];
     var margin = options.keepBuffer;
     var noPruneRange = Bounds(
       tileRange.bottomLeft - CustomPoint(margin, -margin),
@@ -935,7 +934,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
 
     // _update just loads more tiles. If the tile zoom level differs too much
     // from the map's, let _setView reset levels and prune old tiles.
-    if ((zoom - _tileZoom).abs() > 1) {
+    if ((zoom - _tileZoom!).abs() > 1) {
       _setView(center, zoom);
       return;
     }
@@ -943,8 +942,8 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     // create a queue of coordinates to load tiles from
     for (var j = tileRange.min.y; j <= tileRange.max.y; j++) {
       for (var i = tileRange.min.x; i <= tileRange.max.x; i++) {
-        var coords = Coords(i.toDouble(), j.toDouble());
-        coords.z = _tileZoom;
+        final coords = Coords(i.toDouble(), j.toDouble());
+        coords.z = _tileZoom!;
 
         if (!_isValidTile(coords)) {
           continue;
@@ -966,7 +965,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
         (a.distanceTo(tileCenter) - b.distanceTo(tileCenter)).toInt());
 
     for (var i = 0; i < queue.length; i++) {
-      _addTile(queue[i]);
+      _addTile(queue[i] as Coords<double>);
     }
   }
 
@@ -1018,7 +1017,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
       coordsKey: tileCoordsToKey,
       tilePos: _getTilePos(coords),
       current: true,
-      level: _levels[coords.z],
+      level: _levels[coords.z]!,
       imageProvider:
           options.tileProvider.getImage(_wrapCoords(coords), options),
       tileReady: _tileReady,
@@ -1040,7 +1039,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
       }
 
       for (var key in toRemove) {
-        var tile = _tiles[key];
+        var tile = _tiles[key]!;
 
         tile.dispose(true);
         _tiles.remove(key);
@@ -1059,7 +1058,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
       }
 
       for (var key in toRemove) {
-        var tile = _tiles[key];
+        var tile = _tiles[key]!;
 
         tile.dispose(true);
         _tiles.remove(key);
@@ -1067,17 +1066,17 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
     }
   }
 
-  void _tileReady(Coords<double> coords, dynamic error, Tile tile) {
+  void _tileReady(Coords<double> coords, dynamic error, Tile? tile) {
     if (null != error) {
       print(error);
 
-      tile.loadError = true;
+      tile!.loadError = true;
 
       if (options.errorTileCallback != null) {
-        options.errorTileCallback(tile, error);
+        options.errorTileCallback!(tile, error);
       }
     } else {
-      tile.loadError = false;
+      tile!.loadError = false;
     }
 
     var key = _tileCoordsToKey(coords);
@@ -1096,7 +1095,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
       tile.active = true;
     } else {
       tile.startFadeInAnimation(
-        options.tileFadeInDuration,
+        options.tileFadeInDuration!,
         this,
         from: fadeInStart,
       );
@@ -1111,7 +1110,7 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
       // fade-in) to trigger a pruning.
       Future.delayed(
         options.tileFadeInDuration != null
-            ? options.tileFadeInDuration + const Duration(milliseconds: 50)
+            ? options.tileFadeInDuration! + const Duration(milliseconds: 50)
             : const Duration(milliseconds: 50),
         () {
           if (mounted) {
@@ -1123,17 +1122,17 @@ class _TileLayerState extends State<TileLayer> with TickerProviderStateMixin {
   }
 
   CustomPoint _getTilePos(Coords coords) {
-    var level = _levels[coords.z];
-    return coords.scaleBy(getTileSize()) - level.origin;
+    var level = _levels[coords.z as double]!;
+    return coords.scaleBy(getTileSize()) - level.origin!;
   }
 
   Coords _wrapCoords(Coords coords) {
     var newCoords = Coords(
       _wrapX != null
-          ? util.wrapNum(coords.x.toDouble(), _wrapX)
+          ? util.wrapNum(coords.x.toDouble(), _wrapX!)
           : coords.x.toDouble(),
       _wrapY != null
-          ? util.wrapNum(coords.y.toDouble(), _wrapY)
+          ? util.wrapNum(coords.y.toDouble(), _wrapY!)
           : coords.y.toDouble(),
     );
     newCoords.z = coords.z.toDouble();
@@ -1172,29 +1171,29 @@ class Tile implements Comparable<Tile> {
   bool retain;
   bool active;
   bool loadError;
-  DateTime loaded;
-  DateTime loadStarted;
+  DateTime? loaded;
+  late DateTime loadStarted;
 
-  AnimationController animationController;
+  AnimationController? animationController;
 
   double get opacity => animationController == null
       ? (active ? 1.0 : 0.0)
-      : animationController.value;
+      : animationController!.value;
 
   // callback when tile is ready / error occurred
   // it maybe be null forinstance when download aborted
-  TileReady tileReady;
-  ImageInfo imageInfo;
-  ImageStream _imageStream;
-  ImageStreamListener _listener;
+  TileReady? tileReady;
+  ImageInfo? imageInfo;
+  ImageStream? _imageStream;
+  late ImageStreamListener _listener;
 
   Tile({
-    this.coordsKey,
-    this.coords,
-    this.tilePos,
-    this.imageProvider,
+    required this.coordsKey,
+    required this.coords,
+    required this.tilePos,
+    required this.imageProvider,
     this.tileReady,
-    this.level,
+    required this.level,
     this.current = false,
     this.active = false,
     this.retain = false,
@@ -1208,11 +1207,11 @@ class Tile implements Comparable<Tile> {
       final oldImageStream = _imageStream;
       _imageStream = imageProvider.resolve(ImageConfiguration());
 
-      if (_imageStream.key != oldImageStream?.key) {
+      if (_imageStream!.key != oldImageStream?.key) {
         oldImageStream?.removeListener(_listener);
 
         _listener = ImageStreamListener(_tileOnLoad, onError: _tileOnError);
-        _imageStream.addListener(_listener);
+        _imageStream!.addListener(_listener);
       }
     } catch (e, s) {
       // make sure all exception is handled - #444 / #536
@@ -1222,8 +1221,9 @@ class Tile implements Comparable<Tile> {
 
   // call this before GC!
   void dispose([bool evict = false]) {
-    if (evict && imageProvider != null) {
+    if (evict) {
       try {
+        // ignore: return_type_invalid_for_catch_error
         imageProvider.evict().catchError(print);
       } catch (e) {
         // this may be never called because catchError will handle errors, however
@@ -1238,13 +1238,13 @@ class Tile implements Comparable<Tile> {
   }
 
   void startFadeInAnimation(Duration duration, TickerProvider vsync,
-      {double from}) {
+      {double? from}) {
     animationController?.removeStatusListener(_onAnimateEnd);
 
     animationController = AnimationController(duration: duration, vsync: vsync)
       ..addStatusListener(_onAnimateEnd);
 
-    animationController.forward(from: from);
+    animationController!.forward(from: from);
   }
 
   void _onAnimateEnd(AnimationStatus status) {
@@ -1256,13 +1256,13 @@ class Tile implements Comparable<Tile> {
   void _tileOnLoad(ImageInfo imageInfo, bool synchronousCall) {
     if (null != tileReady) {
       this.imageInfo = imageInfo;
-      tileReady(coords, null, this);
+      tileReady!(coords, null, this);
     }
   }
 
-  void _tileOnError(dynamic exception, StackTrace stackTrace) {
+  void _tileOnError(dynamic exception, StackTrace? stackTrace) {
     if (null != tileReady) {
-      tileReady(
+      tileReady!(
           coords, exception ?? 'Unknown exception during loadTileImage', this);
     }
   }
@@ -1290,16 +1290,15 @@ class Tile implements Comparable<Tile> {
 
 class AnimatedTile extends StatefulWidget {
   final Tile tile;
-  final ImageProvider errorImage;
-  final TileBuilder tileBuilder;
+  final ImageProvider? errorImage;
+  final TileBuilder? tileBuilder;
 
   AnimatedTile({
-    Key key,
-    @required this.tile,
+    Key? key,
+    required this.tile,
     this.errorImage,
-    @required this.tileBuilder,
-  })  : assert(null != tile),
-        super(key: key);
+    required this.tileBuilder,
+  }) : super(key: key);
 
   @override
   _AnimatedTileState createState() => _AnimatedTileState();
@@ -1312,7 +1311,7 @@ class _AnimatedTileState extends State<AnimatedTile> {
   Widget build(BuildContext context) {
     final tileWidget = (widget.tile.loadError && widget.errorImage != null)
         ? Image(
-            image: widget.errorImage,
+            image: widget.errorImage!,
             fit: BoxFit.fill,
           )
         : RawImage(
@@ -1324,7 +1323,7 @@ class _AnimatedTileState extends State<AnimatedTile> {
       opacity: widget.tile.opacity,
       child: widget.tileBuilder == null
           ? tileWidget
-          : widget.tileBuilder(context, tileWidget, widget.tile),
+          : widget.tileBuilder!(context, tileWidget, widget.tile),
     );
   }
 
@@ -1333,7 +1332,7 @@ class _AnimatedTileState extends State<AnimatedTile> {
     super.initState();
 
     if (null != widget.tile.animationController) {
-      widget.tile.animationController.addListener(_handleChange);
+      widget.tile.animationController!.addListener(_handleChange);
       listenerAttached = true;
     }
   }
@@ -1352,7 +1351,7 @@ class _AnimatedTileState extends State<AnimatedTile> {
     super.didUpdateWidget(oldWidget);
 
     if (!listenerAttached && null != widget.tile.animationController) {
-      widget.tile.animationController.addListener(_handleChange);
+      widget.tile.animationController!.addListener(_handleChange);
       listenerAttached = true;
     }
   }
@@ -1365,15 +1364,15 @@ class _AnimatedTileState extends State<AnimatedTile> {
 }
 
 class Level {
-  double zIndex;
-  CustomPoint origin;
-  double zoom;
-  CustomPoint translatePoint;
-  double scale;
+  late double zIndex;
+  CustomPoint? origin;
+  late double zoom;
+  late CustomPoint translatePoint;
+  late double scale;
 }
 
 class Coords<T extends num> extends CustomPoint<T> {
-  T z;
+  late T z;
 
   Coords(T x, T y) : super(x, y);
 
diff --git a/lib/src/layer/tile_provider/tile_provider.dart b/lib/src/layer/tile_provider/tile_provider.dart
index 8aa0d4676..62fc0dd1f 100644
--- a/lib/src/layer/tile_provider/tile_provider.dart
+++ b/lib/src/layer/tile_provider/tile_provider.dart
@@ -13,7 +13,7 @@ abstract class TileProvider {
 
   String getTileUrl(Coords coords, TileLayerOptions options) {
     var urlTemplate = (options.wmsOptions != null)
-        ? options.wmsOptions
+        ? options.wmsOptions!
             .getUrl(coords, options.tileSize.toInt(), options.retinaMode)
         : options.urlTemplate;
 
@@ -31,7 +31,7 @@ abstract class TileProvider {
     }
     var allOpts = Map<String, String>.from(data)
       ..addAll(options.additionalOptions);
-    return options.templateFunction(urlTemplate, allOpts);
+    return options.templateFunction(urlTemplate!, allOpts);
   }
 
   double _getZoomForUrl(Coords coords, TileLayerOptions options) {
@@ -91,7 +91,7 @@ class FileTileProvider extends TileProvider {
 class CustomTileProvider extends TileProvider {
   final String Function(Coords coors, TileLayerOptions options) customTileUrl;
 
-  const CustomTileProvider({@required this.customTileUrl});
+  const CustomTileProvider({required this.customTileUrl});
 
   @override
   String getTileUrl(Coords coords, TileLayerOptions options) {
diff --git a/lib/src/map/flutter_map_state.dart b/lib/src/map/flutter_map_state.dart
index 0b5503f80..770c39326 100644
--- a/lib/src/map/flutter_map_state.dart
+++ b/lib/src/map/flutter_map_state.dart
@@ -19,10 +19,11 @@ class FlutterMapState extends MapGestureMixin {
   MapOptions get options => widget.options;
 
   @override
-  MapState mapState;
+  late MapState mapState;
 
-  FlutterMapState(MapController mapController)
-      : mapController = mapController ?? MapController();
+  FlutterMapState(MapController? mapController)
+      : mapController = mapController as MapControllerImpl? ??
+            MapController() as MapControllerImpl;
 
   @override
   void didUpdateWidget(FlutterMap oldWidget) {
@@ -58,11 +59,11 @@ class FlutterMapState extends MapGestureMixin {
   }
 
   Stream<Null> _merge(LayerOptions options) {
-    if (options?.rebuild == null) return mapState.onMoved;
+    if (options.rebuild == null) return mapState.onMoved;
 
     var group = StreamGroup<Null>();
     group.add(mapState.onMoved);
-    group.add(options.rebuild);
+    group.add(options.rebuild!);
     groups.add(group);
     return group.stream;
   }
@@ -98,19 +99,16 @@ class FlutterMapState extends MapGestureMixin {
                 child: Stack(
                   children: [
                     OverflowBox(
-                      minWidth: size.x,
-                      maxWidth: size.x,
-                      minHeight: size.y,
-                      maxHeight: size.y,
+                      minWidth: size.x as double?,
+                      maxWidth: size.x as double?,
+                      minHeight: size.y as double?,
+                      maxHeight: size.y as double?,
                       child: Transform.rotate(
                         angle: mapState.rotationRad,
                         child: Stack(
                           children: [
-                            if (widget.children != null &&
-                                widget.children.isNotEmpty)
-                              ...widget.children,
-                            if (widget.layers != null &&
-                                widget.layers.isNotEmpty)
+                            if (widget.children.isNotEmpty) ...widget.children,
+                            if (widget.layers.isNotEmpty)
                               ...widget.layers.map(
                                 (layer) => _createLayer(layer, options.plugins),
                               )
@@ -120,11 +118,9 @@ class FlutterMapState extends MapGestureMixin {
                     ),
                     Stack(
                       children: [
-                        if (widget.nonRotatedChildren != null &&
-                            widget.nonRotatedChildren.isNotEmpty)
+                        if (widget.nonRotatedChildren.isNotEmpty)
                           ...widget.nonRotatedChildren,
-                        if (widget.nonRotatedLayers != null &&
-                            widget.nonRotatedLayers.isNotEmpty)
+                        if (widget.nonRotatedLayers.isNotEmpty)
                           ...widget.nonRotatedLayers.map(
                             (layer) => _createLayer(layer, options.plugins),
                           )
@@ -168,10 +164,9 @@ class FlutterMapState extends MapGestureMixin {
     if (options is OverlayImageLayerOptions) {
       return OverlayImageLayer(options, mapState, _merge(options));
     }
-    assert(false, """
+    throw (StateError("""
 Can't find correct layer for $options. Perhaps when you create your FlutterMap you need something like this:
 
-    options: new MapOptions(plugins: [MyFlutterMapPlugin()])""");
-    return null;
+    options: new MapOptions(plugins: [MyFlutterMapPlugin()])"""));
   }
 }
diff --git a/lib/src/map/map.dart b/lib/src/map/map.dart
index a9c01bf50..cd7440188 100644
--- a/lib/src/map/map.dart
+++ b/lib/src/map/map.dart
@@ -7,13 +7,13 @@ import 'package:flutter_map/src/core/bounds.dart';
 import 'package:flutter_map/src/core/center_zoom.dart';
 import 'package:flutter_map/src/core/point.dart';
 import 'package:flutter_map/src/map/map_state_widget.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 
 class MapControllerImpl implements MapController {
   final Completer<Null> _readyCompleter = Completer<Null>();
   final StreamController<MapEvent> _mapEventSink = StreamController.broadcast();
   StreamSink<MapEvent> get mapEventSink => _mapEventSink.sink;
-  MapState _state;
+  late MapState _state;
 
   @override
   Future<Null> get onReady => _readyCompleter.future;
@@ -31,13 +31,13 @@ class MapControllerImpl implements MapController {
 
   @override
   MoveAndRotateResult moveAndRotate(LatLng center, double zoom, double degree,
-      {String id}) {
+      {String? id}) {
     return _state.moveAndRotate(center, zoom, degree,
-        source: MapEventSource.mapController, id: id);
+        source: MapEventSource.mapController, id: id!);
   }
 
   @override
-  bool move(LatLng center, double zoom, {String id}) {
+  bool move(LatLng center, double zoom, {String? id}) {
     return _state.move(center, zoom,
         id: id, source: MapEventSource.mapController);
   }
@@ -45,20 +45,21 @@ class MapControllerImpl implements MapController {
   @override
   void fitBounds(
     LatLngBounds bounds, {
-    FitBoundsOptions options =
+    FitBoundsOptions? options =
         const FitBoundsOptions(padding: EdgeInsets.all(12.0)),
   }) {
-    _state.fitBounds(bounds, options);
+    _state.fitBounds(bounds, options!);
   }
 
   @override
+  // TODO could it happen at all that _state isn't set here?
   bool get ready => _state != null;
 
   @override
   LatLng get center => _state.center;
 
   @override
-  LatLngBounds get bounds => _state.bounds;
+  LatLngBounds? get bounds => _state.bounds;
 
   @override
   double get zoom => _state.zoom;
@@ -67,7 +68,7 @@ class MapControllerImpl implements MapController {
   double get rotation => _state.rotation;
 
   @override
-  bool rotate(double degree, {String id}) {
+  bool rotate(double degree, {String? id}) {
     return _state.rotate(degree, id: id, source: MapEventSource.mapController);
   }
 
@@ -95,10 +96,10 @@ class MapState {
 
   double get rotationRad => _rotationRad;
 
-  LatLng _lastCenter;
-  LatLngBounds _lastBounds;
-  Bounds _lastPixelBounds;
-  CustomPoint _pixelOrigin;
+  LatLng? _lastCenter;
+  LatLngBounds? _lastBounds;
+  Bounds? _lastPixelBounds;
+  late CustomPoint _pixelOrigin;
   bool _initialized = false;
 
   MapState(this.options, this.onRotationChanged, this._mapEventSink)
@@ -110,15 +111,15 @@ class MapState {
   Stream<Null> get onMoved => _onMoveSink.stream;
 
   // Original size of the map where rotation isn't calculated
-  CustomPoint _originalSize;
+  CustomPoint? _originalSize;
 
-  CustomPoint get originalSize => _originalSize;
+  CustomPoint? get originalSize => _originalSize;
 
   void setOriginalSize(double width, double height) {
     final isCurrSizeNull = _originalSize == null;
     if (isCurrSizeNull ||
-        _originalSize.x != width ||
-        _originalSize.y != height) {
+        _originalSize!.x != width ||
+        _originalSize!.y != height) {
       _originalSize = CustomPoint<double>(width, height);
 
       _updateSizeByOriginalSizeAndRotation();
@@ -131,19 +132,21 @@ class MapState {
   }
 
   // Extended size of the map where rotation is calculated
-  CustomPoint _size;
+  CustomPoint? _size;
 
   CustomPoint get size => _size ?? CustomPoint(0.0, 0.0);
 
   void _updateSizeByOriginalSizeAndRotation() {
-    final originalWidth = _originalSize.x;
-    final originalHeight = _originalSize.y;
+    final originalWidth = _originalSize!.x;
+    final originalHeight = _originalSize!.y;
 
     if (_rotation != 0.0) {
       final cosAngle = math.cos(_rotationRad).abs();
       final sinAngle = math.sin(_rotationRad).abs();
-      final width = (originalWidth * cosAngle) + (originalHeight * sinAngle);
-      final height = (originalHeight * cosAngle) + (originalWidth * sinAngle);
+      final num width =
+          (originalWidth * cosAngle) + (originalHeight * sinAngle);
+      final num height =
+          (originalHeight * cosAngle) + (originalWidth * sinAngle);
 
       _size = CustomPoint<double>(width, height);
     } else {
@@ -155,29 +158,29 @@ class MapState {
       _initialized = true;
     }
 
-    _pixelOrigin = getNewPixelOrigin(_lastCenter);
+    _pixelOrigin = getNewPixelOrigin(_lastCenter!);
   }
 
   LatLng get center => getCenter() ?? options.center;
 
-  LatLngBounds get bounds => getBounds();
+  LatLngBounds? get bounds => getBounds();
 
   Bounds get pixelBounds => getLastPixelBounds();
 
   void _init() {
     if (options.bounds != null) {
-      fitBounds(options.bounds, options.boundsOptions);
+      fitBounds(options.bounds!, options.boundsOptions);
     } else {
-      move(options.center, zoom);
+      move(options.center, zoom, source: MapEventSource.initialization);
     }
   }
 
   void _handleMoveEmit(LatLng targetCenter, double targetZoom, hasGesture,
-      MapEventSource source, String id) {
+      MapEventSource source, String? id) {
     if (source == MapEventSource.flingAnimationController) {
       emitMapEvent(
         MapEventFlingAnimation(
-          center: _lastCenter,
+          center: _lastCenter!,
           zoom: _zoom,
           targetCenter: targetCenter,
           targetZoom: targetZoom,
@@ -187,7 +190,7 @@ class MapState {
     } else if (source == MapEventSource.doubleTapZoomAnimationController) {
       emitMapEvent(
         MapEventDoubleTapZoom(
-          center: _lastCenter,
+          center: _lastCenter!,
           zoom: _zoom,
           targetCenter: targetCenter,
           targetZoom: targetZoom,
@@ -198,7 +201,7 @@ class MapState {
         source == MapEventSource.onMultiFinger) {
       emitMapEvent(
         MapEventMove(
-          center: _lastCenter,
+          center: _lastCenter!,
           zoom: _zoom,
           targetCenter: targetCenter,
           targetZoom: targetZoom,
@@ -209,7 +212,7 @@ class MapState {
       emitMapEvent(
         MapEventMove(
           id: id,
-          center: _lastCenter,
+          center: _lastCenter!,
           zoom: _zoom,
           targetCenter: targetCenter,
           targetZoom: targetZoom,
@@ -236,8 +239,8 @@ class MapState {
     double degree, {
     hasGesture = false,
     callOnMoveSink = true,
-    MapEventSource source,
-    String id,
+    required MapEventSource source,
+    String? id,
   }) {
     if (degree != _rotation) {
       var oldRotation = _rotation;
@@ -251,7 +254,7 @@ class MapState {
           id: id,
           currentRotation: oldRotation,
           targetRotation: _rotation,
-          center: _lastCenter,
+          center: _lastCenter!,
           zoom: _zoom,
           source: source,
         ),
@@ -268,7 +271,7 @@ class MapState {
   }
 
   MoveAndRotateResult moveAndRotate(LatLng center, double zoom, double degree,
-      {MapEventSource source, String id}) {
+      {required MapEventSource source, required String id}) {
     final moveSucc =
         move(center, zoom, id: id, source: source, callOnMoveSink: false);
     final rotateSucc =
@@ -284,12 +287,12 @@ class MapState {
   bool move(LatLng center, double zoom,
       {hasGesture = false,
       callOnMoveSink = true,
-      MapEventSource source,
-      String id}) {
+      required MapEventSource source,
+      String? id}) {
     zoom = fitZoomToBounds(zoom);
     final mapMoved = center != _lastCenter || zoom != _zoom;
 
-    if (_lastCenter != null && (!mapMoved || !bounds.isValid)) {
+    if (_lastCenter != null && (!mapMoved || !bounds!.isValid)) {
       return false;
     }
 
@@ -315,20 +318,20 @@ class MapState {
       var mapPosition = MapPosition(
           center: center, bounds: bounds, zoom: zoom, hasGesture: hasGesture);
 
-      options.onPositionChanged(mapPosition, hasGesture);
+      options.onPositionChanged!(mapPosition, hasGesture);
     }
 
     return true;
   }
 
-  double fitZoomToBounds(double zoom) {
+  double fitZoomToBounds(double? zoom) {
     zoom ??= _zoom;
     // Abide to min/max zoom
     if (options.maxZoom != null) {
-      zoom = (zoom > options.maxZoom) ? options.maxZoom : zoom;
+      zoom = (zoom > options.maxZoom!) ? options.maxZoom! : zoom;
     }
     if (options.minZoom != null) {
-      zoom = (zoom < options.minZoom) ? options.minZoom : zoom;
+      zoom = (zoom < options.minZoom!) ? options.minZoom! : zoom;
     }
     return zoom;
   }
@@ -338,17 +341,17 @@ class MapState {
       throw Exception('Bounds are not valid.');
     }
     var target = getBoundsCenterZoom(bounds, options);
-    move(target.center, target.zoom);
+    move(target.center, target.zoom, source: MapEventSource.fitBounds);
   }
 
-  LatLng getCenter() {
+  LatLng? getCenter() {
     if (_lastCenter != null) {
       return _lastCenter;
     }
     return layerPointToLatLng(_centerLayerPoint);
   }
 
-  LatLngBounds getBounds() {
+  LatLngBounds? getBounds() {
     if (_lastBounds != null) {
       return _lastBounds;
     }
@@ -358,7 +361,7 @@ class MapState {
 
   Bounds getLastPixelBounds() {
     if (_lastPixelBounds != null) {
-      return _lastPixelBounds;
+      return _lastPixelBounds!;
     }
 
     return getPixelBounds(zoom);
@@ -385,8 +388,8 @@ class MapState {
     zoom = math.min(options.maxZoom, zoom);
 
     var paddingOffset = (paddingBR - paddingTL) / 2;
-    var swPoint = project(bounds.southWest, zoom);
-    var nePoint = project(bounds.northEast, zoom);
+    var swPoint = project(bounds.southWest!, zoom);
+    var nePoint = project(bounds.northEast!, zoom);
     var center = unproject((swPoint + nePoint) / 2 + paddingOffset, zoom);
     return CenterZoom(
       center: center,
@@ -396,7 +399,7 @@ class MapState {
 
   double getBoundsZoom(LatLngBounds bounds, CustomPoint<double> padding,
       {bool inside = false}) {
-    var zoom = this.zoom ?? 0.0;
+    var zoom = this.zoom;
     var min = options.minZoom ?? 0.0;
     var max = options.maxZoom ?? double.infinity;
     var nw = bounds.northWest;
@@ -414,14 +417,14 @@ class MapState {
     return math.max(min, math.min(max, zoom));
   }
 
-  CustomPoint project(LatLng latlng, [double zoom]) {
+  CustomPoint project(LatLng latlng, [double? zoom]) {
     zoom ??= _zoom;
     return options.crs.latLngToPoint(latlng, zoom);
   }
 
-  LatLng unproject(CustomPoint point, [double zoom]) {
+  LatLng unproject(CustomPoint point, [double? zoom]) {
     zoom ??= _zoom;
-    return options.crs.pointToLatLng(point, zoom);
+    return options.crs.pointToLatLng(point, zoom)!;
   }
 
   LatLng layerPointToLatLng(CustomPoint point) {
@@ -432,19 +435,19 @@ class MapState {
     return size / 2;
   }
 
-  double getZoomScale(double toZoom, double fromZoom) {
+  double getZoomScale(double toZoom, double? fromZoom) {
     var crs = options.crs;
     fromZoom = fromZoom ?? _zoom;
     return crs.scale(toZoom) / crs.scale(fromZoom);
   }
 
-  double getScaleZoom(double scale, double fromZoom) {
+  double getScaleZoom(double scale, double? fromZoom) {
     var crs = options.crs;
     fromZoom = fromZoom ?? _zoom;
-    return crs.zoom(scale * crs.scale(fromZoom));
+    return crs.zoom(scale * crs.scale(fromZoom)) as double;
   }
 
-  Bounds getPixelWorldBounds(double zoom) {
+  Bounds? getPixelWorldBounds(double? zoom) {
     return options.crs.getProjectedBounds(zoom ?? _zoom);
   }
 
@@ -452,7 +455,7 @@ class MapState {
     return _pixelOrigin;
   }
 
-  CustomPoint getNewPixelOrigin(LatLng center, [double zoom]) {
+  CustomPoint getNewPixelOrigin(LatLng center, [double? zoom]) {
     var viewHalf = size / 2.0;
     return (project(center, zoom) - viewHalf).round();
   }
@@ -465,9 +468,7 @@ class MapState {
     return Bounds(pixelCenter - halfSize, pixelCenter + halfSize);
   }
 
-  static MapState of(BuildContext context, {bool nullOk = false}) {
-    assert(context != null);
-    assert(nullOk != null);
+  static MapState? maybeOf(BuildContext context, {bool nullOk = false}) {
     final widget =
         context.dependOnInheritedWidgetOfExactType<MapStateInheritedWidget>();
     if (nullOk || widget != null) {
diff --git a/lib/src/map/map_state_widget.dart b/lib/src/map/map_state_widget.dart
index 9e97d05ea..661409229 100644
--- a/lib/src/map/map_state_widget.dart
+++ b/lib/src/map/map_state_widget.dart
@@ -6,9 +6,9 @@ class MapStateInheritedWidget extends InheritedWidget {
   final MapState mapState;
 
   MapStateInheritedWidget({
-    Key key,
-    @required this.mapState,
-    @required Widget child,
+    Key? key,
+    required this.mapState,
+    required Widget child,
   }) : super(key: key, child: child);
 
   @override
@@ -19,7 +19,7 @@ class MapStateInheritedWidget extends InheritedWidget {
     return true;
   }
 
-  static MapStateInheritedWidget of(BuildContext context) {
+  static MapStateInheritedWidget? maybeOf(BuildContext context) {
     return context
         .dependOnInheritedWidgetOfExactType<MapStateInheritedWidget>();
   }
diff --git a/pubspec.yaml b/pubspec.yaml
index 473f541e3..96eede055 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -4,27 +4,32 @@ version: 0.12.0
 repository: https://github.com/johnpryan/flutter_map
 
 environment:
-  sdk: ">=2.7.0 <3.0.0"
+  sdk: '>=2.12.0 <3.0.0'
   flutter: ">=2.0.0"
 
 dependencies:
   flutter:
     sdk: flutter
-  tuple: ^1.0.2
-  latlong: ^0.6.1
+  tuple: ^2.0.0
+  latlong2: ^0.8.0
   positioned_tap_detector_2: ^1.0.0
-  transparent_image: ^1.0.0
+  transparent_image: ^2.0.0
   async: ^2.1.0
-  flutter_image: ^3.0.0
-  vector_math: ^2.0.0
-  proj4dart: ^1.0.4
-  meta: ^1.1.0
-  collection: ^1.14.0
+  flutter_image: any
+  vector_math: ^2.1.0
+  proj4dart: ^2.0.0
+  collection: ^1.15.0
 
 dev_dependencies:
   pedantic: ^1.11.0
-  location: ^2.5.0
+  location: ^4.1.1
   flutter_test:
     sdk: flutter
-  test: ^1.9.0
-  mockito: ^4.1.4
+  test: ^1.16.5
+  mockito: ^5.0.2
+
+dependency_overrides: 
+  flutter_image: 
+    git: 
+      url: "https://github.com/flutter/flutter_image"
+      ref: null-safety
\ No newline at end of file
diff --git a/test/flutter_map_test.dart b/test/flutter_map_test.dart
index 81a9d2118..d33a1b292 100644
--- a/test/flutter_map_test.dart
+++ b/test/flutter_map_test.dart
@@ -4,7 +4,7 @@ import 'dart:io';
 import 'package:flutter/material.dart';
 import 'package:flutter_map/flutter_map.dart';
 import 'package:flutter_test/flutter_test.dart';
-import 'package:latlong/latlong.dart';
+import 'package:latlong2/latlong.dart';
 import 'package:mockito/mockito.dart';
 
 class MockHttpClientResponse extends Mock implements HttpClientResponse {
@@ -18,8 +18,8 @@ class MockHttpClientResponse extends Mock implements HttpClientResponse {
       HttpClientResponseCompressionState.notCompressed;
 
   @override
-  StreamSubscription<List<int>> listen(void Function(List<int> event) onData,
-      {Function onError, void Function() onDone, bool cancelOnError}) {
+  StreamSubscription<List<int>> listen(void Function(List<int> event)? onData,
+      {Function? onError, void Function()? onDone, bool? cancelOnError}) {
     return _stream.listen(onData,
         onError: onError, onDone: onDone, cancelOnError: cancelOnError);
   }
@@ -42,7 +42,7 @@ class MockClient extends Mock implements HttpClient {
 
 class MockHttpOverrides extends HttpOverrides {
   @override
-  HttpClient createHttpClient(SecurityContext securityContext) => MockClient();
+  HttpClient createHttpClient(SecurityContext? securityContext) => MockClient();
 }
 
 void main() {