--- a/lib/src/widgets/emoji_picker/emoji_builder.dart
+++ b/lib/src/widgets/emoji_picker/emoji_builder.dart
@@ -1,7 +1,7 @@
 import 'dart:convert';
+import 'dart:io';
 
 import 'package:build/build.dart';
-import 'package:http/http.dart' as http;
 import 'package:interstellar/src/utils/trie.dart';
 
 Builder emojiBuilder(BuilderOptions options) =>
@@ -29,15 +29,9 @@
   };
 
   Future<String> _generateContent() async {
-    final dataResponse = await http.get(
-      Uri.parse('$_sourcePrefix/compact.raw.json'),
-    );
-    final dataJson = jsonDecode(dataResponse.body);
+    final dataJson = jsonDecode(await File('@compact.raw.json@').readAsString()) as List;
 
-    final messagesResponse = await http.get(
-      Uri.parse('$_sourcePrefix/messages.raw.json'),
-    );
-    final messagesJson = jsonDecode(messagesResponse.body);
+    final messagesJson = jsonDecode(await File('@messages.raw.json@').readAsString()) as Map<String, dynamic>;
 
     final s = StringBuffer()
       ..write('''
@@ -53,8 +47,9 @@
 
     final emojiGroups = <String>[];
 
-    for (var i = 0; i < (messagesJson['groups'] as List).length; i++) {
-      final group = messagesJson['groups'][i];
+    final groups = messagesJson['groups'] as List;
+    for (var i = 0; i < groups.length; i++) {
+      final group = groups[i] as Map<String, dynamic>;
 
       assert(group['order'] == i, 'Emoji group order value should match index');
 
@@ -61,4 +56,4 @@
-      emojiGroups.add(group['message']);
+      emojiGroups.add(group['message'] as String);
     }
 
     s
@@ -72,7 +67,8 @@
 
     {
       var i = 0;
-      for (final emoji in dataJson) {
+      for (final emojiItem in dataJson) {
+        final emoji = emojiItem as Map<String, dynamic>;
         if (emoji['group'] == null || emoji['order'] == null) continue;
 
         assert(emoji['order'] == i + 1, 'Emoji order value should match index');
@@ -84,9 +80,9 @@
               : emoji['emoticon']),
         ];
 
-        trie.addChild(Trie.normalizeTerm(emoji['label']), {i});
+        trie.addChild(Trie.normalizeTerm(emoji['label'] as String), {i});
         for (final tag in tags) {
-          trie.addChild(Trie.normalizeTerm(tag), {i});
+          trie.addChild(Trie.normalizeTerm(tag as String), {i});
         }
 
         s
@@ -93,9 +89,9 @@
           ..write('const Emoji("')
-          ..write(emoji['unicode'])
+          ..write(emoji['unicode'] as String)
           ..write('","')
-          ..write(emoji['label'])
+          ..write(emoji['label'] as String)
           ..write('",')
-          ..write(emoji['group'])
+          ..write(emoji['group'].toString())
           ..write('),\n');
 
         i++;