Flet 1.0 Released for Production Python App Development

The Flet team announced the release of Flet 1.0 last week, marking the framework as ready for production application development. Flet is an open-source Python framework that enables developers to build user interfaces for web, desktop, and mobile applications using only Python. It achieves this by rendering its UI with Flutter, Google's UI toolkit, allowing developers to write Python code that Flet translates into Material and Cupertino widgets displayed on iOS, Android, Windows, macOS, Linux, and web browsers. This approach eliminates the need for developers to write code in Dart, Swift, Kotlin, or JavaScript.

The Flet 1.0.0 release is available on PyPI under the Apache 2.0 license and requires Python 3.10 or newer for the Software Development Kit. Installation is straightforward using pip with the command `pip install 'flet[all]'`. The `flet build` command generates deployable artifacts for Windows, macOS, Linux, iOS, Android, and the web. The command-line interface supports eight target platforms: `apk`, `aab`, `ipa`, `ios-simulator`, `windows`, `macos`, `linux`, and `web`.

Extensive testing has been integrated into the Flet development process. The framework runs unit tests across Python versions 3.10 to 3.14, alongside tests for the Flutter rendering engine. Control and example integration tests verify behavior and compare screenshots to detect functional bugs and visual regressions. Python binary package tests are conducted on Android and the iOS simulator, with the mobile pipeline building for Python 3.12, 3.13, and 3.14. Furthermore, `flet build` integration tests compile applications across these Python versions for all six supported platforms, and `flet test` launches a packaged application and drives it on all five native platforms, including Linux ARM64. Developers can implement similar testing strategies for their own applications using pytest, running tests via `flet test` against the packaged build and performing screenshot comparisons on Android and iOS.

Flet 1.0 bundles Python 3.12, 3.13, or 3.14 with applications, and web builds utilize the corresponding Pyodide release. Developers can select their preferred Python version for their projects. The Flet package index now hosts over 100 packages, including popular libraries such as NumPy, pandas, Matplotlib, Pillow, SciPy, scikit-learn, cryptography, and pydantic-core, along with supporting native libraries. The `mobile-forge` pipeline automates the building of Python wheels for iOS and Android, ensuring compatibility and ease of deployment for mobile applications. The project has been in development for approximately four years, culminating in this production-ready release.