---
title: "Flutter SDK 3.3 migration guide"
canonical_url: "https://www.nutrient.io/guides/flutter/migration-guides/flutter-3-3-migration-guide/"
md_url: "https://www.nutrient.io/guides/flutter/migration-guides/flutter-3-3-migration-guide.md"
last_updated: "2026-06-08T17:11:05.525Z"
description: "Migration guide for Nutrient Flutter SDK version 3.3 with breaking changes, API updates, and upgrade instructions."
---

In [Nutrient Flutter SDK 3.3](https://www.nutrient.io/blog/pspdfkit-flutter-3-3-flutter-3-support/), we moved package files from `lib/src` to `lib`. To update your code, change your `pspdfkit_flutter` package imports as follows:

```diff

-import 'package:pspdfkit_flutter/src/widgets/pspdfkit_widget.dart';
+import 'package:pspdfkit_flutter/pspdfkit_widget.dart';

```

We also updated `main.dart` to `pspdfkit.dart`. This means that the `PSPDFKit` static class import will now be as follows:

```diff

-import 'package:pspdfkit_flutter/src/main.dart';
+import 'package:pspdfkit_flutter/pspdfkit.dart';

```
---

## Related pages

- [Flutter 1 10 4 Migration Guide](/guides/flutter/migration-guides/flutter-1-10-4-migration-guide.md)
- [Flutter SDK 3 migration guide](/guides/flutter/migration-guides/flutter-3-migration-guide.md)
- [Flutter 3 12 Migration Guide](/guides/flutter/migration-guides/flutter-3-12-migration-guide.md)
- [Flutter 3 6 Migration Guide](/guides/flutter/migration-guides/flutter-3-6-migration-guide.md)
- [Flutter 3 2 Migration Guide](/guides/flutter/migration-guides/flutter-3-2-migration-guide.md)
- [Flutter 3 9 Migration Guide](/guides/flutter/migration-guides/flutter-3-9-migration-guide.md)
- [Flutter SDK 4 migration guide](/guides/flutter/migration-guides/flutter-4-migration-guide.md)
- [Download and run the migration script.](/guides/flutter/migration-guides/flutter-5-migration-guide.md)
- [Upgrade to the latest Flutter version](/guides/flutter/migration-guides/upgrading.md)
- [Flutter SDK 4.2 migration guide](/guides/flutter/migration-guides/flutter-4-2-migration-guide.md)