diff --git a/CHANGELOG.md b/CHANGELOG.md
index 464b254..0edac27 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,13 +1,8 @@
-# Change Log
+## 0.0.2
 
-All notable changes to this project will be documented in this file.
+* Migrate to Null safety.
 
-The format is based on [Keep a Changelog](http://keepachangelog.com/)
-and this project adheres to [Semantic Versioning](http://semver.org/).
+## 0.0.1
 
-## [0.0.1] - 2021-03-30
-
-### Added
-
-- **Initial release**
-- lit_relative_date_time - A Flutter package to generate relative dates to show differences in time in localized and human-readable format..
\ No newline at end of file
+* Initial release
+* lit_relative_date_time - A Flutter package to generate relative dates to show differences in time in localized and human-readable format.
\ No newline at end of file
diff --git a/example/pubspec.lock b/example/pubspec.lock
index 8f65338..a93a2f4 100644
--- a/example/pubspec.lock
+++ b/example/pubspec.lock
@@ -45,7 +45,7 @@ packages:
       path: ".."
       relative: true
     source: path
-    version: "0.0.1"
+    version: "0.0.2"
   meta:
     dependency: transitive
     description:
@@ -80,5 +80,5 @@ packages:
     source: hosted
     version: "2.1.0"
 sdks:
-  dart: ">=2.12.0-0 <3.0.0"
+  dart: ">=2.12.0 <3.0.0"
   flutter: ">=1.17.0"
diff --git a/lib/lit_relative_date_time.dart b/lib/lit_relative_date_time.dart
index 5487c72..869db86 100644
--- a/lib/lit_relative_date_time.dart
+++ b/lib/lit_relative_date_time.dart
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// @dart = 2.8
+
 
 /// A Flutter package to generate relative dates to show differences in time in localized and human-readable format.
 ///
diff --git a/lib/localization/relative_date_format.dart b/lib/localization/relative_date_format.dart
index 5a0dcdc..465d16f 100644
--- a/lib/localization/relative_date_format.dart
+++ b/lib/localization/relative_date_format.dart
@@ -75,31 +75,26 @@ class RelativeDateFormat {
         return _isSingular(relativeDateTime)
             ? _timeUnitsSingular[0]
             : _timeUnitsPlural[0];
-        break;
 
       case LitTimeUnit.minute:
         return _isSingular(relativeDateTime)
             ? _timeUnitsSingular[1]
             : _timeUnitsPlural[1];
-        break;
 
       case LitTimeUnit.hour:
         return _isSingular(relativeDateTime)
             ? _timeUnitsSingular[2]
             : _timeUnitsPlural[2];
-        break;
 
       case LitTimeUnit.day:
         return _isSingular(relativeDateTime)
             ? _timeUnitsSingular[3]
             : _timeUnitsPlural[3];
-        break;
 
       default:
         return _isSingular(relativeDateTime)
             ? _timeUnitsSingular[4]
             : _timeUnitsPlural[4];
-        break;
     }
   }
 
diff --git a/lib/model/relative_date_localization.dart b/lib/model/relative_date_localization.dart
index ea1aac4..cd37fe6 100644
--- a/lib/model/relative_date_localization.dart
+++ b/lib/model/relative_date_localization.dart
@@ -1,5 +1,3 @@
-import 'package:flutter/foundation.dart';
-
 /// Model class to describe all data required for localizing the formatted
 /// [RelativeDateTime].
 class RelativeDateLocalization {
@@ -72,14 +70,14 @@ class RelativeDateLocalization {
   /// ],
   /// ```
   const RelativeDateLocalization({
-    @required this.languageCode,
-    @required this.timeUnitsSingular,
-    @required this.timeUnitsPlural,
-    @required this.prepositionPast,
-    @required this.prepositionFuture,
-    @required this.atTheMoment,
-    @required this.formatOrderPast,
-    @required this.formatOrderFuture,
+    required this.languageCode,
+    required this.timeUnitsSingular,
+    required this.timeUnitsPlural,
+    required this.prepositionPast,
+    required this.prepositionFuture,
+    required this.atTheMoment,
+    required this.formatOrderPast,
+    required this.formatOrderFuture,
   });
 }
 
diff --git a/lib/model/relative_date_time.dart b/lib/model/relative_date_time.dart
index 8e66737..3acbe1d 100644
--- a/lib/model/relative_date_time.dart
+++ b/lib/model/relative_date_time.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/foundation.dart';
 import 'package:lit_relative_date_time/lit_relative_date_time.dart';
 import 'package:lit_relative_date_time/controller/relative_date_time_controller.dart';
 
@@ -14,8 +13,8 @@ class RelativeDateTime {
   ///
   /// Ensure to provide two comparable [DateTime] objects.
   RelativeDateTime({
-    @required this.dateTime,
-    @required this.other,
+    required this.dateTime,
+    required this.other,
   });
 
   /// Returns the calculated [TimeDifference].
diff --git a/lib/model/time_difference.dart b/lib/model/time_difference.dart
index cb74baf..4e7d1e1 100644
--- a/lib/model/time_difference.dart
+++ b/lib/model/time_difference.dart
@@ -1,4 +1,3 @@
-import 'package:flutter/foundation.dart';
 import 'package:lit_relative_date_time/model/lit_time_unit.dart';
 
 /// A model class to describe a relative date time based on the largest [TimeUnit]
@@ -22,8 +21,8 @@ class TimeDifference {
   ///
   /// * [unit] is the time unit of the date.
   const TimeDifference({
-    @required this.value,
-    @required this.unit,
+    required this.value,
+    required this.unit,
   });
 
   /// States whether the [TimeDifference]'unit contains the smallest value available (second).
diff --git a/pubspec.lock b/pubspec.lock
index 69f70f1..10c9218 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -47,5 +47,5 @@ packages:
     source: hosted
     version: "2.1.0"
 sdks:
-  dart: ">=2.12.0-0 <3.0.0"
+  dart: ">=2.12.0 <3.0.0"
   flutter: ">=1.17.0"
diff --git a/pubspec.yaml b/pubspec.yaml
index 95c05be..dbef5a2 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -1,10 +1,10 @@
 name: lit_relative_date_time
 description: A Flutter package to generate relative dates to show differences in time in localized and human-readable format.
-version: 0.0.1
+version: 0.0.2
 homepage: https://www.github.com/litlifesoftware/lit_relative_date_time
 
 environment:
-  sdk: ">=2.8.0 <3.0.0"
+  sdk: ">=2.12.0 <3.0.0"
   flutter: ">=1.17.0"
 
 dependencies: