diff --git a/lib/src/commands/export.dart b/lib/src/commands/export.dart
index 29a90c6..77e6f7a 100644
--- a/lib/src/commands/export.dart
+++ b/lib/src/commands/export.dart
@@ -64,7 +64,7 @@ run: onepub login
                 'Found $user');
       }
       await API().checkVersion();
-      final response = waitForEx(API().exportMemberToken(user));
+      final response = await API().exportMemberToken(user);
 
       if (response.success) {
         onepubToken = response.token!;
@@ -86,9 +86,8 @@ run: onepub login
             exitCode: 1, message: 'You may only pass one argument to --file.');
       }
 
-      final exportFile = TokenExportFile(pathToFile)
-        ..onepubToken = onepubToken
-        ..save();
+      final exportFile = TokenExportFile(pathToFile)..onepubToken = onepubToken;
+      await exportFile.save();
 
       print('''
 
diff --git a/lib/src/commands/import.dart b/lib/src/commands/import.dart
index aea3da7..7c5a88d 100644
--- a/lib/src/commands/import.dart
+++ b/lib/src/commands/import.dart
@@ -88,11 +88,11 @@ Use `onepub export` to obtain the OnePub token.
       throw ExitException(exitCode: 1, message: organisation.errorMessage!);
     }
 
-    OnePubSettings.use()
+    final settings = OnePubSettings.use()
       ..operatorEmail = 'not set during import'
       ..obfuscatedOrganisationId = organisation.obfuscatedId
-      ..organisationName = organisation.name
-      ..save();
+      ..organisationName = organisation.name;
+    await settings.save();
 
     OnePubTokenStore().addToken(
       onepubApiUrl: OnePubSettings.use().onepubApiUrlAsString,
diff --git a/lib/src/commands/login.dart b/lib/src/commands/login.dart
index 857943a..3df09ee 100644
--- a/lib/src/commands/login.dart
+++ b/lib/src/commands/login.dart
@@ -49,8 +49,8 @@ class OnePubLoginCommand extends Command<int> {
       final settings = OnePubSettings.use()
         ..obfuscatedOrganisationId = auth.obfuscatedOrganisationId
         ..organisationName = auth.organisationName
-        ..operatorEmail = auth.operatorEmail
-        ..save();
+        ..operatorEmail = auth.operatorEmail;
+      await settings.save();
 
       final onepubApiUrl = settings.onepubApiUrlAsString;
 
diff --git a/lib/src/commands/pub/private.dart b/lib/src/commands/pub/private.dart
index 7a08f42..7f0eaa0 100644
--- a/lib/src/commands/pub/private.dart
+++ b/lib/src/commands/pub/private.dart
@@ -3,11 +3,9 @@
  * Written by Brett Sutton <bsutton@onepub.dev>, Jan 2022
  */
 
-import 'dart:io';
-
 import 'package:args/command_runner.dart';
-import 'package:dcli/dcli.dart' hide PubSpec;
-import 'package:pubspec2/pubspec2.dart';
+import 'package:dcli/dcli.dart';
+import 'package:pubspec_manager/pubspec_manager.dart';
 import 'package:scope/scope.dart';
 import 'package:url_builder/url_builder.dart';
 
@@ -66,36 +64,34 @@ run: onepub login
     final currentOrganisationName = settings.organisationName;
     final url = settings.onepubApiUrlAsString;
 
-    final pubspec = await PubSpec.loadFile(project.pathToPubSpec);
-    if (pubspec.publishTo != null) {
-      if (pubspec.publishTo.toString() == url) {
-        print(orange('${pubspec.name} is already a private package.'));
-        return;
-      }
-
-      await API().checkVersion();
-      final organisation = await getOrganisation(obfuscatedOrganisationId);
-      if (organisation == null) {
-        print(orange('${pubspec.name} is already a private package '
-            'for another organisation'));
-      } else {
-        print(orange('${pubspec.name} is already a private package of '
-            '${organisation.name}'));
-      }
-      if (!confirm('Do you want to change the organisation to '
-          '$currentOrganisationName?')) {
-        print(red('Action cancelled'));
-        return;
-      }
+    final pubspec = PubSpec.loadFromPath(project.pathToPubSpec);
+    if (pubspec.publishTo.toString() == url) {
+      print(orange('${pubspec.name} is already a private package.'));
+      return;
+    }
+
+    await API().checkVersion();
+    final organisation = await getOrganisation(obfuscatedOrganisationId);
+    if (organisation == null) {
+      print(orange('${pubspec.name} is already a private package '
+          'for another organisation'));
+    } else {
+      print(orange('${pubspec.name} is already a private package of '
+          '${organisation.name}'));
+    }
+    if (!confirm('Do you want to change the organisation to '
+        '$currentOrganisationName?')) {
+      print(red('Action cancelled'));
+      return;
     }
 
-    final pubspecUpdated = pubspec.copy(publishTo: Uri.parse(url));
-    await pubspecUpdated.save(Directory(project.pathToProjectRoot));
+    pubspec.publishTo.set(url);
+    pubspec.saveTo(project.pathToProjectRoot);
 
     print('''
-${pubspecUpdated.name} has been marked as a private package for the organisation ${settings.organisationName}.
+${pubspec.name} has been marked as a private package for the organisation ${settings.organisationName}.
 
-Run 'dart/flutter pub publish' to publish ${pubspecUpdated.name} to OnePub
+Run 'dart/flutter pub publish' to publish ${pubspec.name} to OnePub
 
 See ${urlJoin(settings.onepubWebUrl, 'publish')}
 ''');
diff --git a/lib/src/entry_point.dart b/lib/src/entry_point.dart
index d1adf40..04ccb20 100644
--- a/lib/src/entry_point.dart
+++ b/lib/src/entry_point.dart
@@ -34,7 +34,7 @@ Future<void> entrypoint(
     final runner = MyRunner(args, executableName, _description, commandSet);
     try {
       printPreamble();
-      runner.init();
+      await runner.init();
       await runner.run(args);
     } on FormatException catch (e) {
       printerr(e.message);
diff --git a/lib/src/exceptions.dart b/lib/src/exceptions.dart
index e8555e5..72fddee 100644
--- a/lib/src/exceptions.dart
+++ b/lib/src/exceptions.dart
@@ -33,3 +33,7 @@ class APIException extends OnePubCliException {
 class NotInitialisedException extends OnePubCliException {
   NotInitialisedException(super.message);
 }
+
+class SettingsException extends OnePubCliException {
+  SettingsException(super.message);
+}
diff --git a/lib/src/my_runner.dart b/lib/src/my_runner.dart
index d9bc441..ae5e4b8 100644
--- a/lib/src/my_runner.dart
+++ b/lib/src/my_runner.dart
@@ -37,8 +37,8 @@ import 'pub/command/upgrade.dart';
 import 'pub/command/uploader.dart';
 import 'pub/command/version.dart';
 import 'pub/io.dart';
-import 'pub/log.dart' hide red;
 import 'pub/log.dart' as plog;
+import 'pub/log.dart' hide red;
 
 enum CommandSet { opub, onepub }
 
@@ -62,7 +62,7 @@ class MyRunner extends CommandRunner<int> implements PubTopLevel {
   }
   CommandSet commandSet;
 
-  void init() {
+  Future<void> init() async {
     PubTopLevel.addColorFlag(argParser);
 
     results = argParser.parse(args);
@@ -76,7 +76,7 @@ class MyRunner extends CommandRunner<int> implements PubTopLevel {
     }
 
     if (commandSet == CommandSet.onepub) {
-      OnePubSettings.install(dev: results['dev'] as bool);
+      await OnePubSettings.install(dev: results['dev'] as bool);
     }
   }
 
diff --git a/lib/src/onepub_settings.dart b/lib/src/onepub_settings.dart
index a5168c2..035a9a0 100644
--- a/lib/src/onepub_settings.dart
+++ b/lib/src/onepub_settings.dart
@@ -200,12 +200,12 @@ class OnePubSettings {
   String get operatorEmail => _settings.asString('operatorEmail');
 
   // ignore: discarded_futures
-  void save() => waitForEx(_settings.save());
+  Future<void> save() async => _settings.save();
 
-  void saveTo(String tempSettingsDir) {
+  Future<void> saveTo(String tempSettingsDir) async {
     _settings.filePath = join(tempSettingsDir, defaultSettingsFilename);
     // ignore: discarded_futures
-    waitForEx(_settings.save());
+    await _settings.save();
   }
 
   String resolveApiEndPoint(String command, {String? queryParams}) {
@@ -241,7 +241,7 @@ class OnePubSettings {
   //   });
   // }
 
-  static void install({required bool dev}) {
+  static Future<void> install({required bool dev}) async {
     final create = !exists(defaultPathToSettings);
     final settings = OnePubSettings._load(create: create);
 
@@ -251,7 +251,7 @@ class OnePubSettings {
     }
 
     if (settings.onepubUrl == null || settings.onepubUrl!.isEmpty || dev) {
-      settings.config(dev: dev);
+      await settings.config(dev: dev);
 
       print(orange('Installed OnePub version: $packageVersion.'));
     }
@@ -268,13 +268,15 @@ class OnePubSettings {
   }
 
   ///
-  void config({required bool dev}) {
-    promptForConfig(dev: dev);
+  Future<void> config({required bool dev}) async {
+    print('Configure OnePub');
+
+    await promptForConfig(dev: dev);
   }
 
   final testingFlagPath = join(HOME, '.onepubtesting');
 
-  void promptForConfig({required bool dev}) {
+  Future<void> promptForConfig({required bool dev}) async {
     var url = OnePubSettings.defaultOnePubUrl;
     if (dev) {
       print('Configure OnePub');
@@ -282,9 +284,8 @@ class OnePubSettings {
       testingFlagPath.write('onepubtesting');
     }
 
-    OnePubSettings.use()
-      ..onepubUrl = url
-      ..save();
+    final settings = OnePubSettings.use()..onepubUrl = url;
+    await settings.save();
   }
 
   /// If the settings are using a non-standard url (e.g. not https;//onepub.dev)
diff --git a/lib/src/util/token_export_file.dart b/lib/src/util/token_export_file.dart
index 016f4af..2ca0c2e 100644
--- a/lib/src/util/token_export_file.dart
+++ b/lib/src/util/token_export_file.dart
@@ -32,8 +32,7 @@ class TokenExportFile {
   late final String pathToExportFile;
   late final SettingsYaml settings;
 
-  // ignore: discarded_futures
-  void save() => waitForEx(settings.save());
+  Future<void> save() async => settings.save();
 
   bool get hasToken => settings.validString(onepubTokenKey);
   String get onepubToken => settings.asString(onepubTokenKey);
diff --git a/pubspec.lock b/pubspec.lock
index 422b3e1..08d4b5b 100644
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -189,10 +189,10 @@ packages:
     dependency: "direct main"
     description:
       name: file
-      sha256: "1b92bec4fc2a72f59a8e15af5f52cd441e4a7860b49499d69dfa817af20e925d"
+      sha256: "5fc22d7c25582e38ad9a8515372cd9a93834027aacf1801cf01164dac0ffa08c"
       url: "https://pub.dev"
     source: hosted
-    version: "6.1.4"
+    version: "7.0.0"
   file_utils:
     dependency: "direct main"
     description:
@@ -201,6 +201,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "1.0.1"
+  fixnum:
+    dependency: transitive
+    description:
+      name: fixnum
+      sha256: "25517a4deb0c03aa0f32fd12db525856438902d9c16536311e76cdc57b31d7d1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.0"
   frontend_server_client:
     dependency: "direct main"
     description:
@@ -428,8 +436,15 @@ packages:
   pubspec2:
     dependency: "direct main"
     description:
-      name: pubspec2
-      sha256: "7b1fd81927f1da6d88457c83b51134e1bc8cb07638bd8d9e205b2ce1cd9ec091"
+      path: "../../pubspec_manager"
+      relative: true
+    source: path
+    version: "1.0.0-alpha.14"
+  quiver:
+    dependency: transitive
+    description:
+      name: quiver
+      sha256: b1c1ac5ce6688d77f65f3375a9abb9319b3cb32486bdc7a1e0fdf004d7ba4e47
       url: "https://pub.dev"
     source: hosted
     version: "2.4.2"
@@ -461,10 +476,10 @@ packages:
     dependency: "direct main"
     description:
       name: scope
-      sha256: e0c880d8f0db2ffd2accd63eeb02396748f3b8a2f71bce4b7d3f8dab75fc8a74
+      sha256: "80cf1cb727791fdaaa4131817974a6084815ed59b9ab02ef352c3a1badea488b"
       url: "https://pub.dev"
     source: hosted
-    version: "3.0.0"
+    version: "4.1.0"
   settings_yaml:
     dependency: "direct main"
     description:
diff --git a/pubspec.yaml b/pubspec.yaml
index da13952..52bbaf5 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -57,8 +57,8 @@ dependencies:
   pool: 1.5.1
   posix: 5.0.0
   pub_semver: 2.1.4
-  pubspec2: 2.4.2
   pubspec_lock: ^3.0.2
+  pubspec_manager: ^1.0.0-alpha.14
   quiver: 3.2.1
   random_string: 2.3.1
   scope: 3.0.0
diff --git a/test/impersonate_user.dart b/test/impersonate_user.dart
index f40a390..f5b801e 100644
--- a/test/impersonate_user.dart
+++ b/test/impersonate_user.dart
@@ -60,8 +60,8 @@ Future<void> impersonateMember({
         ..operatorEmail = member.email
         ..onepubUrl = testSettings.onepubUrl
         ..organisationName = member.organisationName
-        ..obfuscatedOrganisationId = member.obfuscatedOrganisationId
-        ..save();
+        ..obfuscatedOrganisationId = member.obfuscatedOrganisationId;
+      await settings.save();
 
       // set an alternate location for the token store
       await OnePubTokenStore.withPathTo(tempSettingsDir, () async {
diff --git a/test/src/commands/pub/add_dep_test.dart b/test/src/commands/pub/add_dep_test.dart
index d5ecb37..3ec748f 100644
--- a/test/src/commands/pub/add_dep_test.dart
+++ b/test/src/commands/pub/add_dep_test.dart
@@ -8,7 +8,8 @@ import 'package:onepub/src/api/api.dart';
 import 'package:onepub/src/entry_point.dart';
 import 'package:onepub/src/my_runner.dart';
 import 'package:path/path.dart' hide equals;
-import 'package:pub_semver/pub_semver.dart';
+import 'package:pub_semver/pub_semver.dart' as ps;
+import 'package:pubspec_manager/pubspec_manager.dart';
 import 'package:scope/scope.dart';
 import 'package:test/test.dart';
 
@@ -32,12 +33,16 @@ void main() {
 
             // increment the package 2 version number so we can publish it.
             final pathToPackage2Pubspec = dartProject.pathToPubSpec;
-            final pubspec = PubSpec.fromFile(pathToPackage2Pubspec);
+            final pubspec = PubSpec.loadFromPath(pathToPackage2Pubspec);
+
             final versions = await API()
                 .fetchVersions(member.obfuscatedOrganisationId, packageName);
+            final next = ps.Version.parse(versions.latest.version).nextMinor;
+
             pubspec
-              ..version = Version.parse(versions.latest.version).nextMinor
-              ..save(pathToPackage2Pubspec);
+              ..version = VersionBuilder.parse(next.canonicalizedVersion)
+                  .attach(pubspec)
+              ..saveTo(pathToPackage2Pubspec);
 
             // add new version to change log to stop pub publish complaining.
             join(pathToProjectRoot, 'CHANGELOG.md')
@@ -62,7 +67,7 @@ void main() {
           member: member,
           action: () async {
             var pubSpec = dartProject.pubSpec;
-            expect(pubSpec.dependencies.containsKey('test_packag_2'), isFalse);
+            expect(pubSpec.dependencies.exists('test_packag_2'), isFalse);
 
             // run onepub add <dep>
             final progress = 'dart $pathToOnePubScript pub add test_packag_2'
@@ -70,8 +75,8 @@ void main() {
             expect(progress.exitCode, equals(0));
 
             // load the updated pubspec
-            pubSpec = PubSpec.fromFile(dartProject.pathToPubSpec);
-            expect(pubSpec.dependencies.containsKey('test_packag_2'), isTrue);
+            pubSpec = PubSpec.loadFromPath(dartProject.pathToPubSpec);
+            expect(pubSpec.dependencies.exists('test_packag_2'), isTrue);
           });
     });
   });
diff --git a/test/src/commands/pub/private_test.dart b/test/src/commands/pub/private_test.dart
index 252c7d2..34614ca 100644
--- a/test/src/commands/pub/private_test.dart
+++ b/test/src/commands/pub/private_test.dart
@@ -8,6 +8,7 @@ import 'package:onepub/src/entry_point.dart';
 import 'package:onepub/src/my_runner.dart';
 import 'package:onepub/src/onepub_settings.dart';
 import 'package:onepub/src/version/version.g.dart';
+import 'package:pubspec_manager/pubspec_manager.dart';
 import 'package:scope/scope.dart';
 import 'package:test/test.dart';
 import 'package:url_builder/url_builder.dart';
@@ -31,7 +32,7 @@ void main() {
           action: () async {
             final settings = OnePubSettings.use();
             final organisationName = settings.organisationName;
-            expect(dartProject.pubSpec.pubspec.publishTo, isNull);
+            expect(dartProject.pubSpec.publishTo, isNull);
 
             final size = stat(dartProject.pathToPubSpec).size;
 
@@ -54,8 +55,8 @@ void main() {
             final url = OnePubSettings.use().onepubWebUrl;
             expect(clean.contains('See ${urlJoin(url, 'publish')}'), isTrue);
 
-            final pubSpec = PubSpec.fromFile(dartProject.pathToPubSpec);
-            expect(pubSpec.pubspec.publishTo.toString(),
+            final pubSpec = PubSpec.loadFromPath(dartProject.pathToPubSpec);
+            expect(pubSpec.publishTo.toString(),
                 equals(settings.onepubApiUrlAsString));
 
             expect(stat(dartProject.pathToPubSpec).size, greaterThan(size));
diff --git a/test/test_settings.dart b/test/test_settings.dart
index 068a680..16ca98e 100644
--- a/test/test_settings.dart
+++ b/test/test_settings.dart
@@ -27,8 +27,7 @@ class TestSettings {
   // set organisationId(String obsfucatedId) =>
   //     _settings['organisationId'] = obsfucatedId;
 
-  // ignore: discarded_futures
-  void save() => waitForEx(_settings.save());
+  Future<void> save() async => _settings.save();
 
   String get pathToTestSettings {
     final pathToTest = DartProject.self.pathToTestDir;